Yaesu FRG-9600 VHF/UHF radio

~~~ DISCRIMINATOR MODIFICATION ~~~

Disclaimer: The following is given in good faith. I cannot be held responsible for any omissions or errors, or to any damage caused to any radio howsoever caused....All care but no responsibility!!!!

Tools required:

• cross head screwdriver
• 25 watt, fine tip soldering iron
• tweezers or needle tip pliers
• side cutters
• needle files
• sharp knife (to cut one pcb track)
• a small container to hold screws & washers.*

* The last item is very important. There are many screws to remove. It is all too easy to loose one. Make a habit of ALWAYS putting the removed screws & washers into a small container such as a 35mm film container, cup, coffee jar lid etc. NEVER ever leave them loose on the table or bench.

Components required:

• 1 x .01 capacitor
• 1 x small cable tie
• Approx 12 to 18 inches of smallish diameter Audio cable (coaxial screened essential)
• 1 cup of coffee

To gain access to the NFM discriminator on this radio is easy BUT only do it if you feel capable of doing one very fine solder connection....

Basically what you have to do is connect a short length of audio coax, via a small capacitor, from pin 14 of the mixer/nfm discriminator chip (MC3357P). to an unused socket on the back of the radio. There are several sockets on the back and I have used the "MPX" socket on my radio because I will never want to put a stereo multiplexer on it! The instructions below relate to the MPX socket. You can choose any of the sockets that you will not need but you must cut the tracks leading to that socket before adding soldering the coax thereto!

Step-by-step Instructions

1. Disconnect power and other cables at the back.
2. Remove top and bottom covers.
3. From the top, locate the N.F.M. board (4.25 inches [115mm] from the back panel)
4. Very carefully solder one leg of the 0.1µF capacitor to the solder side of the pcb where pin 14 pokes out. Be careful to correctly identify this pin AND be careful with the soldering, it is a fine bit of soldering and is easy to short out this to the adjacent pads. CHECK and double check that you have done a good "clean" solder job here -It's vital to be very careful - I cannot stress this enough! Leave thecapacitor hanging in the air for the moment...
5. Use a small needle file to drill a small hole in the top portion of the nfm pcb where there are no tracks. through this hole, thread a small cable tie and leave in situ for the time being. (Later, you will secure the audio coax here. See step 9 below.)
6. With a sharp knife, scrape a section of the solder resist from the top, right hand "Earth" track (as seen from the solder side of the pcb) and tin it with solder (To confirm that you have the correct track, it is the track also connected to the can of the xtal on that board!)
7. Prepare the coax by:- (a) Stripping back the outer insulation by about one inch. (25mm), twist the shielding together and tin it for about .25 inch [6mm] and then trim it down to this length. (b) Stripping back the inner by about 1/16 inch (2mm) and tin the inner conductor.
8. Solder the screen of the coax to the earth track so that it will present the inner conductor very close to or touching the free leg of the capacitor.
9. Now clamp this coax cable into position using the cable tie (as mentioned in 5 above) to secure it.
10. Solder the inner conductor to the free end of the capacitor
11. Orientate the radio so that the front panel is facing you and looking into the radio from the top, thread the free end of the coax to the bottom, by way of gap between the main pcb and the case at the back, right hand side (near the two white connector plugs) Tuck the coax under the big choke (the thing that looks like a transformer). BE CAREFUL not to put any strain on the coax. Leave a little slack ...
12. now turn the radio upside down and orientate it so that the dial is facing your right. The coax should be poking up at the left hand side nearest you! To use the "MPX" jack socket as the access point:-
13. Identify the 3 mounting pins of the MPX jack. They are 2 5/8 inch [65mm] from the edge facing you, of the main pcb . The pin on the left is the earth (ground) pin. The centre if the "live" pin and the right pin is not used electronically (only as a mechanical mounting point and is ignored in this mod)
14. Carefully cut the track leading to the centre "live" pin about half way along its length (This removes the unused "MPX" signal to the jack socket.
15. Prepare the audio coax appropriately and solder the screen to the earth pin and the inner core to the middle pin. Replace the top and bottom covers, making sure that there is no strain on the coax and that it is not being "pinched" by the covers.

IMPORTANT - Add a "MOD NOTE to the inside of the radio and also in the instruction book:-

• a small self adhesive label stuck to the metal screen on the underside of the pcb with words to the effect : "21 Jan 98 - track cut to remove mpx and coax added to give access to the NFM discriminator output"
• Similar label on the back denoting the MPX now to be "NFM Discriminator"
• If you have a circuit diagram, note the change also thereon!!!

The discriminator output is at a fixed level (about .7 volt) and totally isolated from the volume control - the setting of the volume control will not effect the discriminator level. The squelch control WILL cut in and out on the discriminator line in the same fashion as on the normal audio.

BTW: e-hum, why do you want a discriminator output on the radio anyway?:>)

Waring! Do not attempt to do this if you do not feel confident when using soldering equipment. Do not blame me if you screw up your receiver or do any damage to anything you are using.

First write down all the stored frequencies, in case the memories of the receiver get lost. Then turn it off and disconnect all cables.

I will not explain how to open the case. If you can't find it out by yourself, you sure won't be able to do the work.

What you see above, is the Printed Circuit Board (PCB) of the FRG9600, seen from the bottom.



What you need: 1 resistor 1 KOhm 1/4 or 1/2 Watt, 3 pieces of wire, soldering iron GREEN SQUARE: This is the 1 KOhm resistor, soldered between the pin # 1 (Counting from the top) and the nearby ground terminal of the pin array marked J8001/J9001, next to the black rubber piece.

Beware, the the sensitivity is not very good in the expanded frequency range, but it is still usable. Also interference from the computer might matter. I've also noticed that some receivers might be better, others might be less good, depending on how the front-end is aligned. I'm working on this, so stay tuned :-).

Now turn around the opened FRG9600, so that you can look inside from the top.

Locate the BAND UNIT. This is the vertical circuit board with a metal frame, closest to the front panel. Next to it, on the main Circuit Board, there is the text BAND UNIT written. You have to solder the 3 jumper wires on this Band Unit.
When you look at the front of the Band Unit, near its top, you will see 6 empty holes, marked on the below drawing with x.
 

                               (Top)
               ------------------------------------
              |                                    |
              |   x.......x          x.......x     |
              |     _                   x.......x  |
              |    |S|                             |
              |    |0|                             |
              |    |1|                             |

You have to solder the jumpers marked x.....x, either by connecting the soldering points on the back, or inserting the jumpers through the holes on the front.
If you have the switch S01 inserted, this must be on the OFF position. Usually this switch is not installed, its use is to limit the frequency range of the FRG, probably for some countries who required it.

Now check your solderings. They must be clean, and must not touch the nearby pins. Check also that you have not left any metal chips from the jumpers or the soldering lead inside the receiver. Close the box, connect the cables and turn it on.
With the dial you can now select all frequencies between 0.0000 and 999.0000 Mhz, but only the range 20.0000 - 950.0000 will be operational.

Waring: On some frg's the frequency on the display is off by 27.250 Mhz from the real frequency you are receiving on the low band, i.e. if you want to listen to 50.000 Mhz you have to enter 22.750 Mhz.
 

1. Open the lid on the metal box. Inside there's the circuit in the following figure.
   
    
2. Tune the FRG on 460 Mhz.
   On the PLL unit, below the IC MC 145158, you can see the pin marked TP02. With a digital tester measure the voltage on this TP02, it should be around 1,1-1,5 V. The PLL unit is, among the two high printed circuits, the one closer to our metal box, next to it there's written 'PLL UNIT'.
   
   
   
    
3. On the figure, next to the red arrow, there's a horizontal copper strip, with another vertical copper strip strip soldered at its end. These two strips make an angle of 90°.
   
   With a very fine tipped soldering iron melt the soldering which connects these two strips, and bend the vertical strip a bit towards the beginning of the horizontal strip, to shorten a bit this loop.
   
   A fraction of a millimeter (about 0,5 mm) should be enough. Measure again the voltage on TP02, receiver tuned on 460 Mhz. The voltage should be now around 0,6 V. If not, you can still make small adjustments to the copper link. Now, with the FRG tuned on 950 Mhz, you should have a voltage on TP02 of about 30,5 V.
   
    
4. Now, let's improve the reception sensibility in this high band.
   Connect the digital tester on pin nr. 12 of the IC MC3357, the FM discriminator.
   The voltage should vary from about 0,6 V with no signal received, to about 1,2 V with maximum signal, with the squelch unblocked.
   Tune the receiver to a frequency around 460 mhz, which has to be busy with some signal. (A repeater output would do fine)
   
   Next to the green arrow in above figure there are some pairs of copper strips, which make some resonating links. With a little NON INDUCTIVE screwdriver adjust these strips a little closer or farther from each other, until you read the maximum value on the tester, always whlie receiving the same signal.
   
   Repeat this step also on higher frequencies, the corrections on the copper links must be very fine.

Now the reception on 900 and more mhz should be much better.
 

Some transistor equivalents
BC507 = NPN, 40V 0,2Amp = BC174, BC182, BC190, BC546
BC517 = NPN Darlington, 40V 0,4Amp = BC875, BC877, 2SC4017

Thanks to Giovanni, HE9LSA, who supplied me with the drawing for a Circuit Board:

Thanks to Anthony, WB8MLA for the pictures and the modification to the circuit, to make it all fit inside a serial connector:

A description for this, by Anthony:

The chip I used is the MAX232ACPE which is available from DigiKey. The part number is # MAX232ACPE-ND and is about $4.25 U.S. Their phone number is 1-800-344-4539 With this chip, you use little tiny .1 caps in the exact same place where your 22uF caps were. Also, the .1 caps do not have to be polarized!
I also can tell you that there is another chip, that doesn't require any capacitors at all, and its called the MAX233..(its a little bigger though) I did some minor changes to your circuit, and am happy with the results! I used a GE940011 Darlington (a little more gain) rather than the BC517. But, what I am most happy about is, I was able to fit all the parts into the DB-25 shell, and no power supply necessary! The way I did this was to steal power from the RTS line (pin 4) and the DTR line (pin 20) by soldering the anode ends of two 1N914 to each pin, and then TYING the cathode ends (the cathode end has the band around it) of both together. This gives me double the current (which is usually about 12 volts @ 12 ma or so). From there, I feed the squelch transistors collector (about 12 volts!) and, I also tie the input of the 78L05 regulator here, to get 5 volts out of the other side, which runs the MAX232A very nicely! Also, the MAX232A draws less current!
Even the joystick components are inside the DB-25 shell..

Do not attempt to do this if you do not feel confident when using soldering equipment.

This mod is also available at http://members.tripod.com/~brossi/schema.htm
 

Providing features that have never been offered before, the FRG-9600 is an all-mode scanning receiver that covers 60 through 905 MHZ continuously and comes complete with 100 keypad-programmable memory channels.

In addition to FM wide (for FM and Television broadcasts), FM narrow (for two-way police, military, business and amateur communications) and AM wide and narrow (for aeronautical and amateur communications), the FRG-9600 also provides SSB (single sideband) reception up to 460 MHZ, allowing reception of amateur and military SSB, as well as the new ACSB mode now being utilized by the military and experimentally as the mode of the future for VHF. The SSB mode also provides for easy reception of CW (radiotelegraph), and a front panel tuning knob is provided to simplify the tuning of SSB, CW and narrow-band AM frequencies.
Seven scanning/tuning rates between 100 Hz and 100 kHz assure quick and efficient tuning and scanning in all modes.

The scanning system allows either full or limited (keypad programmed) band scanning as well as memory channel scanning with auto-resume. In addition to carrier sensing scan stop, audio scan stop sensing is also selectable to avoid stopping on inactive "carrier-only" channels.
Scanning steps are selectable, with the wide steps indicated on the front panel display. Signal strength is indicated by a dual color graphic S-meter on the front display. A 24-hour clock/timer is also included, along with a recorder output (for automatic power on/off switching and recording of transmissions at any time). Additional jacks provide CPU band selection outputs, multiplexed (FM wide) output, AF and RF mute and other control signals for maximum expansion potential with future options or for those who wish to provide their own add-on hardware for special applications. A mobile mounting bracket is also supplied for use in an automobile.

The Yaesu CAT system provides a direct control link to the CPU in the FRG-9600, thus allowing operators of personal computers to add virtually unlimited customized control functions in software (such as multiple, organized memory banks, automatic tuning and customized scanning systems) using most of any personal computers and a Yaesu FIF CAT interface unit.

For AC operation the FRG-9600 requires one of the optional PA-4 series AC adapters, available from all dealers where the receiver is sold. A television video IF unit may also be installed as an option, allowing reception of television images (NTSC format) with a video monitor connected to the video jack on the rear panel.

Specifications

    
Frequency Range                   60 - 905 MHZ (up to 460 MHZ for SSB)
     
Modes, 3dB Bandwidth              FM Narrow  (15 kHz BW)
                                  FM Wide (180 kHz BW)
                                  AM Narrow (2.4 kHz BW)
                                  AM Wide   (6 kHz BW)
                                  SSB (2.4 kHz BW)
     
Conversion Schemes                Triple (FM-N, AM, SSB)
                                  Double (FM-W)
                                  Single (Optional TV Video Unit)
          
Intermediate Frequencies          45.754, 10.7 MHZ and 455 kHz
     
Image Rejection                   60 - 460 MHZ  -50dB typical
                                  460 - 905 MHZ  -40dB typical
     
Typical Sensitivity               FM-N  0.5uV (for 12dB SINAD)
                                  FM-W  1.0uV (for 12dB SINAD)
                                  AM-N  1.0uV (for 10dB S+N/N)
                                  AM-W  1.5uV (for 10dB S+N/N)
                                  SSB  1.0uV (for 15dB S+N/N)

Tuning Steps                      FM-N: 5/10/12.5/25 kHz
                                  FM-W: 100 kHz
                                  AM-N: 100 Hz/1 kHz
                                  AM-W: 5/10/12.5/25 kHz
     
Memory Channels                   100 Channels
     
Audio Output                      1W (into 8ê with less than 10% THD)
     
Power Supply Voltage              12 - 15 VDC
     
Power Supply Current              Operating: 550 mA (maximum)
                                  Power Off: 100 mA
                                  DC Supply Off: 3 uA max (B/U)
     
Case Size (WxHxD)                 180 x 80 x 220 (mm)
     
Weight                            2.2 kg (4.9 lbs) without options
     
Supplied Accessories              Whip antenna (0.6m)
                                  DC power cord (1.8m)
                                  MMB-28 Mobile mounting bracket
                                  Wire Stand
     
Options                           AC-DC Wall Adapter (PA-4B for 110-120v
                                  PA-4C for 220-240 v)
                                  Video Unit (NTSC)
                                  SP-55 external speaker

Front panel controls

1. SQL (Squelch)

This control adjusts the sensitivity of the all mode squelch system, which quiets the receiver audio unless a signal is received that is stronger than the threshold level set by this control. If you wish to intercept all the signals (strong and weak), this control should be set fully counter-clockwise. However, for normal FM-N and M reception this control should normally be rotated clockwise just to the point where the received noise disappears (FM) of is reduced (AM, SSB). This control is disabled in the FM-W mode.

2. TONE (outer knob)

This control adjusts the treble and bass response of the audio amplifier in the receiver to allow the most comfortable listening position. Normally it is set to about the center (12 0'clock) position with clockwise rotation decreasing the bass response and counterclockwise having the opposite effect.

3. VOL (and OFF)

The inner knob is the main ON/OFF switch and volume control for the receiver. It should be adjusted for a comfortable volume on a signal or noise when the SQL control is set counter-clockwise. Rotate the control fully counterclockwise into the click-stop to switch off the receiver when it is not being used. The clock/timer and memory backup functions will not be affected.

4. AF SCAN

This two-position grey push button selects the scan-stop condition. In the undepressed (out) position, the scanner will stop whenever any signal is detected (whether or not it is modulated by voice). When this switch is depressed, the scanner will stop only on those signals that have audio modulation, skipping over unmodulated carriers.

5. PHONES

Standard monaural or stereo headphones with either a 2- or 3-contact plug may be connected to this jack. Either arrangement will reproduce the monaural style of audio in both ears.
Inserting a plug into this jack disables the internal speaker, or external speaker if connected.

Impedance of the headphones should be 32ê for best results.

6. ATT (ATTenuator)

This two-position grey push button decreases the level of all signals from the antenna to protect the receiver input from overloading by very strong signals. Normally this button is not depressed provided maximum receiver sensitivity.

7. M CLEAR (Memory Clear)

Pressing this grey button when receiving a memory channel clears all data from that channel ( a beep will sound) and transfers the frequency and the mode data to the Dial state. That memory will then be vacant (and thus ignored by the scanner) until data is rewritten to it from the Dial state. The button is disabled while receiving frequencies in the Dial state.

8. Tuning Knob

This knob allows convenient step-tuning across the band in the Dial state, or through the memories. Tuning steps are determined by the MODE and STEP buttons.

9. DOWN and UP keys

If pressed momentarily, these two large metallic keys move the displayed receiving frequency down or up by one tuning step when the receiver is in the Dial state or the next stored memory channel when in the Memory state. If pressed and held for more than a half-second, the scanner will be activated. Press either of these keys again to deactivate the scanner.

10. Small Metallic Function Keys

A beep will sound when any function controlled by these keys is activated. If a beep does not sound, or if two beeps sound in quick succession, the function is not activated because that function is not accessible in the current operating state.

STEP selects the frequency steps for tuning and scanning in the Dial state. These are 100Hz or 1kHz for LSB, USB and AM-N operation, and 5, 10, 12.5 or 25kHz for AM-W and FM-N (step size for these latter two modes is shown at the right side of the display). This key is disabled in the FM-W mode and at all times in the Memory state.

MODE selects the receiver detector type and IF bandwidth when receiving in the Dial state. Repeated pressing of this key cycles through the modes as follows:

     LSB USB AM-N AM-W FM-N FM-W

The selected mode is displayed just above the frequency. The MODE key is deactivated when receiving on a memory.

PRI (Priority) toggles the automatic priority channel checking function on and off. This function momentarily tests a preselected "priority" memory for activity every three seconds during normal reception on other frequencies. See the "Operation" section for details.

D/M (Dial-to-Memory) transfers the frequency and mode data from Dial to a memory.
The memory channel (two digits) must be keyed in beforehand or the data will be stored in the selected memory. Pressing this key does not change the selected state (Dial or Memory); it only transfers the data.

DIAL selects the Dial state (from the Memory state). The frequency and mode last used in the Dial state will be recalled (so the Dial actually serves as a 101st memory). Specific details are provided in the "Operation" section.

MR (Memory Recall) selects reception on a memory (the Memory state) after receiving a frequency in the Dial state. If a two-digit memory channel is keyed in before pressing this key, memory operation will be on that channel; otherwise, operation will be on the memory that was last used (before the Dial state was last entered), unless that memory was cleared. See the "Operation" section.

CLOCK displays the clock/timer status (without affecting reception). The first press of this key activates the clock display and allows setting of the time (by the numeric keypad). Pressing the CLOCK key again activates the Timer On mode, which displays (and allows resetting of) the time at which the receiver will be switched on automatically. Pressing CLOCK again activates the Timer Off mode, which is similar to the Timer On mode. Pressing CLOCK once more activates the Timer On/Off select mode, indicated by display of a single decimal in the center of the display:

     TIME ON TIME OFF TIME "."(ON/OFF)

To escape the clock/timer status and return to frequency display, press DIAL or MR. See the "Operation" section for more details.

M/D (Memory-to-Dial) transfers the frequency and mode data from the memory to the Dial, overwriting previous data in the Dial. The source memory channel digits may be keyed in first, or the last selected memory will be transferred. Operation will always be shifted to the Dial when this key is pressed, and the original memory data will remain intact (in the memory channel).
This button is also used in conjunction with the DOWN/UP keys for Limited Band Operation, described later.

11. CE (ON) (Clear Enter & Timer On)

The Clear Enter function of this blue key allows cancellation of the numerical digits that have been entered by mistake on the keypad. The Timer On function is used only in the time ON/OFF select mode (when the display shows only a single decimal and "OFF" or "ON OFF"), to toggle the auto-ON timer on and off.

12. White Keypad Keys (1-9 and 0 [OFF])

The numeric keys allow entry of frequency, memory channel or clock/timer setting, according to the operating status of the receiver selected by the metallic function buttons. In the timer ON/OFF select mode, the "0" key toggles the auto-OFF timer.

13. TIMER SET

This blue key is enabled only in the clock/timer modes to set the clock and the on or off times after keying in the desired time digits on the keypad.

14. Display

During regular reception the display shows the relative received signal strength on the 2-color bar-graph indicator at the left, the frequency in the center and the reception mode indicated just above the frequency digits. When receiving in the Memory state, the two-digit memory channel is displayed at the right. PRI or DIAL is indicated between the bar-graph and frequency when these features are activated. OFF or ON/OFF are shown just above the memory channel when these timer features are activated. In the clock/timer modes only time (or ".") is displayed as well as the ON/OFF status when set.

Rear panel jacks

15. 13.8 VDC

This coaxial jack accepts the DC supply voltage for the receiver (12-15VDC). Current is 550mA when the receiver is on and 100 mA when off. This supply should be connected at all times to retain the clock/timer settings. The optional PA-4B or -4C Wall Adapters can be used to supply the operating voltage from the AC line, however AC voltage must never be connected directed to this jack. See the "Installation" section for further details and important precautions.

16. 8 VDC

This RCA jack provides 8VDC ñ10% at up to 200mA for powering external devices. The center contact is positive.

17. REC

This jack provides constant level (approx. 70mV @ 50kê) audio output, which is unaffected by the VOL and TONE controls. Use this jack for tape recording or data decoding purposes where a constant audio level is required.

18. EXT SPKR (External Speaker)

This two-contact mini phone jack is for connection of an external loudspeaker such as the Yaesu SP-55 with an impedance of 4 to 16 ê. When a plug is inserted into this jack the internal speaker is disabled.

19. AF MUTE (Potentiometer)

This control sets the squelch threshold level at which signals will be heard in the FM-W mode only. It should be normally be set so that the noise and signals that are too weak to be heard clearly (without distortion) are muted.

20. MPX (Multiplex)

This two-contact mini phone jack provides output from the FM-W detector (in the FM-W mode) for an external stereo demultiplexer (not available from Yaesu). Level is approximately 400mV (rms) @ 50kê with -6dB ripple between 20Hz and 60kHz.

21. VIDEO

This RCA jack provides baseband video output (approx. 1V p-p) when the optional Video Unit is installed in the receiver. Use this jack for connection to a video monitor.

22. TV AGC (Potentiometer)

This control allows adjustment of the video Automatic Gain Control which provides constant level video output with varying received signal levels when the optional Video Unit is installed.

23. MUTE

This RCA jack allows the receiver to be disabled (in any mode) by shorting the center and outer contacts of the jack. This should be done whenever the FRG-9600 is utilized in conjunction with a transmitter. Do not apply any voltage to this jack.

24. BAND

This four-pin molex jack provides binary band data (on three pins, the other being signal ground) for possible future options. Maximum open circuit voltage that may be applied is 30V.

25. CAT

This six-pin DIN jack provides connections for a microcomputer interface unit (such as the Yaesu FIF series). Pin-out is shown below:

                         PIN 1          Ground
                         PIN 2          Serial Out
                         PIN 3          Serial In
                         PIN 4          PTT Signal
                         PIN 5          AGC Signal
                         PIN 6          BUSY Signal

26. ANT

This type M coaxial jack is for connection of the antenna. The supplied telescoping whip antenna may be used for casual listening, however, a proper outdoor antenna should be used for optimum performance. See the "Installation" section for details.

Installation

Proper performance of the FRG-9600 depends on correct installation. Please take a moment to study this section carefully before connecting the receiver to the power source. While the setup procedure for the FRG-9600 is simple, permanent damage to the receiver can occur if improper voltage is applied or if external connections are improperly made.

Initial Inspection

After carefully removing the FRG-9600 from the carton, inspect it for any signs of physical damage. Rotate the knobs and push the buttons, checking each for normal freedom of action. If damage is suspected write down your observations and notify the shipping company (if the set was shipped to you) or your dealer immediately. Save the carton and packing material for possible future use later.

Physical Location of the Receiver

The FRG-9600 can be located just about any place, but there are a few important factors to keep in mind for certain installations. Of course it will be necessary to keep the top panel clear if the internal speaker is to be used, and necessary space for the rear panel connectors and access to the front panel controls should be considered - especially in mobile mounting. Do not locate the FRG-9600 in front of a heater vent or directly above a heat-generating device.

There are two other factors to consider in certain applications: the distance to the antenna feedpoint (when the receiver is used with an external antenna) and the proximity and grounding or shielding of computer equipment (when the FRG-9600 is used in conjunction with same). For optimum reception the receiver should be located as close to the antenna as possible, so that the feedline length is kept to a minimum. However, unless a computer is well shielded for RF noise (a rare case), the antenna may pick up objectionable noise from the computer if they are very close to one another.

Experimentation in several different locations, perhaps with different ground connections, may be necessary to determine the best overall placement of the receiver, antenna and computer.

Power Connections

The FRG-9600 is equipped for operation from 12 to 15 VDC, which may be supplied from the optional PA-4B or PA-4C AC-DC adapter when operating the receiver from the AC mains. The PA-4B is for use with 110-120 VAC only, while the PA-4C is for use with 220-240 VAC only.

The FRG 9600 requires 550mA when the receiver is on and 100mA for clock/timer operation when the receiver is off, so be sure that any battery or DC source that will be used is capable of handling this current. The center pin of the coaxial 13.8 VDC power jack on the receiver must connected to the positive side of the DC source. Make certain that the plug used for this connection has the correct size hole for the center pin of this jack, and that the polarity is not reversed (or the receiver will be damaged). Be certain that the VOL control is set to OFF before connecting the power plug to the rear panel.

WARNING

Never apply AC power to the rear panel power jack of the receiver. Never connect DC voltage of more than 15 volts to the power jack. Make certain that the center contact of the power jack is connected to the positive side of the supply. Failure to observe these precautions will damage the equipment and void the warranty.

The SP-55 External Speaker is an optional accessory for the FRG-9600 allowing the source of audio from the receiver to be repositioned for optimum listening. Especially practical for the noisy environment, the SP-55 includes its own swivel-type mounting bracket and is available from your Yaesu dealer.

Mobile Installation

The FRG-9600 must only be installed in automobiles having a negative ground electrical system. The receiver should be located where the display and controls are easily accessible and should be securely affixed using the supplied MMB-28 mobile mounting bracket. The receiver may be installed in any position without adversely affecting its performance, however it should not be mounted near a heater vent or where it could interfere with the safe operation of the vehicle.

Mobile Mounting Procedure

1. Use the mounting bracket as a template for positioning the mounting holes, after determining the proper location with sufficient clearance for the receiver. Use a 3/16" bit for drilling the holes. Secure the bracket with the screws, washers and nuts supplied.
   
    
2. Screw the mounting knobs loosely to the receiver using the supplied flat washers.
   
    
3. Align the mounting knobs with the notches in the bracket, and slide the receiver backward and upward into the bracket. Then tighten the knobs to affix the receiver securely.

To remove the receiver from the bracket, first loosen the four knobs and then pull the receiver straight forward, with slight upward pressure at the rear if necessary.

Before connecting the power cable, the maximum battery charging voltage should be checked to ensure that it remains below 15V when the engine is at high speed. If there is more than 15V present the voltage regulator of the automobile should be adjusted before connecting the receiver.

Power connections may be made to the cigarette lighter or other convenient circuit, but if the supply is switch off when the motor ignition switch is off, then the clock will reset to 00:00. Therefore, if clock operation is desired, an unswitched circuit should be used (or direct connection to the battery). In this case, remember that 100mA will be drawn at all times, so that the car battery charge will be depleted if the automobile is to stored for a considerable time. Use good quality insulated stranded copper wire and make certain that POSITIVE (+) is connected to the center contact of the coaxial power plug.

Antenna Installation and Connection

The FRG-9600 is designed to operate only with an antenna connected to the rear panel connector. While the supplied telescoping whip antenna will give fair results on strong local signals on some frequencies if the radio is well located, optimum performance requires a good outdoor antenna located as high and in the clear as possible, with good quality feedline to the receiver.

Only 50ê coaxial cable should be used for the connection and it should be as short as possible while still allowing the antenna to be mounted high above surrounding objects. For general AM and FM scanning and monitoring a vertical ground plane antenna is usually preferred, since it does not need to be rotated to cover all directions. However, in some locations a high gain unidirectional (vertical) Yagi antenna is best if most activity is in one direction from the receiving station, or if a rotator is available and the extra gain required. The best antenna performance will usually be obtained at some sacrifice of frequency coverage (bandwidth) so if optimum performance is to be achieved at all frequencies, several different antennas should be used. SSB, CW and TV modes generally use horizontal polarization, while FM uses vertical polarization. Both of these orientations should be taken into account when choosing and installing the antennas. Contact your local dealer for advice on the best antenna for your needs.

MUTE Jack Connection

The MUTE terminal on the rear panel allows the receiver to be silenced during transmission when the FRG-9600 is used for two-way communication in conjunction with a transmitter or transceiver. Separate antennas, well isolated from each other, must be used to prevent damage to the receiver. Shorting the MUTE terminal contacts will silence the receiver.

REC Jack Connection

Receiver audio is available at high impedance (50kê) from the REC jack on the rear panel for direct connection to the high-impedance (HI-Z) audio input of a tape recorder. Shielded cable should be used for interconnections to minimize noise pickup that might otherwise interfere with reception. Note that the VOL and TONE controls do not affect the audio at the REC jack.

Personal computer interconnection

The CAT system allows external control of the mode and frequency functions of the FRG-9600 via a variety of brands of personal computers (not available from Yaesu). "CAT" stands for "Computer Aided Transceiver," since this system was originally developed for amateur radio transceivers.

Interconnection between the computer and receiver requires a digital interface unit to convert the parallel 8-bit ASCII data from the computer into 4800 bits/sc serial data at the correct voltage level required by the FRG-9600. Yaesu offers the FIF series CAT interface units for this purpose. Some of these units are for installation on certain brands of computers, however the FIF-232C unit is designed for use with any computer that is equipped with an EIA standard RS-232C serial output port capable of 4800 bits/sec operation. Except for the FIF-232C, all of the Yaesu CAT interface units also include an analog-to-digital converter to allow the computer to measure the relative strength of received signals (for interactive operation between the computer and receiver when so programmed).

The FIF interface units include a DIN plug for connection to the CAT jack on the rear of the FRG-9600 and some means of easy connection to (or installation within) the computer. The FIF-232C also requires connection at the AC line.

Additional details are provided at the end of the "Operation" section of this manual and in the manual supplied with each FIF interface unit.

NOTE: While the FRG-9600 was designed to be well shielded against RF interference from computer noise, personal computers are generally not designed to limit the amount of RF noise that they may produce, except within very broad limitations. Some computers may produce enough noise to interfere with reception, particular on lower frequencies. Some computer manufacturers and suppliers offer modifications and outboard noise filters to suppress RF noise, but Yaesu cannot accept responsibility for interference that may be caused by your computer.
However, if such interference in encountered, it can often be minimized or eliminated by the following steps (first tune in the noise on the receiver and switch the computer off and on to determine that it is the source of interference):

1. Locate the antenna as far as practicable from the receiver and computer, and use only the best coaxial cable feedline available with proper connection to the coaxial jack on the receiver and impedance at the antenna. This usually calls for a self-resonant (and generally narrow-band) antenna.
   
    
2. Pay special attention to the chassis grounding of the receiver and computer. In some cases it may be necessary to not connect the earth or receiver chassis ground to the computer chassis. A specially filtered signal ground line for the CAT system is provided in the CAT interface cable. However, there is no fixed rule for grounding to minimize noise so some experimentation may be necessary.
   
    
3. Use only good quality shielded cable for all external connections to the receiver and to the computer. Noise can easily be picked up by a device such as an external speaker cable or tape recorder and passed to the receiver. Disconnecting one accessory at a time from the receiver may help to isolate the culprit.

Operation

Basic operation of the FRG-9600 is quite simple. However, some of the advanced digital functions can be confusing at first if the operator is not familiar with the operation intended by the designers. Please read this section through carefully while trying out each function on the receiver after making sure that the power and antenna connections have been made correctly as described in the previous section.

Rotate the VOL control out of the click-stop to turn on the radio. If it has not been used previously, the display will show "60.000.0" (MHz) in the "FM-N" mode, "% kHz" steps at the left and "DIAL" to the right of the frequency. Otherwise the frequency, mode and status last used (before the radio was last switched off) will be displayed. If you wish to clear all data (frequency, mode and memories) at any time, see the "Memory Backup" reset procedure later in the manual.

FM Broadcast Reception - the FM-W mode

The wide FM mode is described first mainly because it is generally the most universal in terms of frequency band and channel steps and the simplest to receive. Make sure that the grey ATT and AF SCAN switches (to the left of the main knob) are set to their undepressed (out) positions. Press the MODE button (just to the right of the main Knob) once to verify that the "FM-W" mode is now displayed above the frequency. If not, continue pressing the MODE button while watching for the correct mode display.

Use the white numerical keys to enter the frequency of a local FM broadcasting station (usually this will be between 88 and 108 MHz, but remember that most television stations also transmit their audio on FM-W). Note that if the frequency is below 100 MHz it will be necessary to key in "0" first. For example, if the station is 90.5 MHz, press 0,9,0,5. Each time a digit is entered the next digit to the right will blink indicating that it is to be entered next (if needed - you need only enter the digits you wish to change). If you accidentally press a wrong digit key, just press the orange CE key to clear your entry and start over.

Once the desired frequency is shown on the display (with leading zero if below 100 MHz, press the DIAL button just below the display. The flashing digit will stop flashing, the leading zero (if present) will disappear and the FRG-9600 will now be receiving on the entered frequency. Adjust the VOL control at a comfortable listening level and set the TONE control as desired.

Either the main tuning knob or the DOWN/UP buttons (above the knob) can be used to tune to a different station if desired. Tuning steps will always be 100 kHz in the FM-W mode.
Alternately, the scanning function can be used if the AF MUTE control on the rear panel is set properly:

1. Using a small screwdriver, first set the control fully counterclockwise.
   
    
2. Tune to a clear channel (where only noise is heard) and gradually turn the control clockwise just to the point where the noise is silenced.

To activate the scanner press the DOWN or UP button and hold it for a « second. The scanner will skip over vacant channels and stop close to the next lower or higher station (a beep will sound). When the scanner has paused the digits will each blink once from left to right. If you press the DOWN or UP button again, the scanner will be disengaged and you can then use the DOWN/UP buttons or the main knob to tune in the station clearly.

If the DOWN or UP button is not pressed to disengage the scanner it will resume scanning automatically after the rightmost digit has blinked. Note that in this condition the scanner will continue indefinitely in the same direction to the very edge of the receiving range (60 or 905 MHz) and then jump to the other edge and keep scanning. Use Limited Band Operation (mentioned later) to keep the scanner within a certain range.

Memory Storage, Recall and Memory Scanning

The FRG-9600 has two "states" of operation: Dial or Memory, selected by the DIAL or MR (Memory Recall) keys respectively. The Dial state, used in the procedures above and indicated by "DIAL" shown just to the left of the frequency on the display, allows selection of frequency, mode and tuning steps with unrestricted knob tuning, scanning or keypad entries anywhere within the range of the receiver. The Memory state, on the other hand, permits instant recall of any frequency and mode previously stored from the Dial state. Operation in the Memory state is indicated by the presence of "CH" and the memory channel number to the right of the frequency displayed. In the Memory state scanning and stepping (with the DOWN/UP buttons) is in blocks of ten memory channels.

The 100 memory channels are numbered from 00 to 99. Note that two digits are always used to describe a channel (i.e. 00, 01, 02 ... 09, 10, 11, etc.), since two digits must be used when entering a memory channel number on the keypad. For scanning purposes, each group of channels with the same tens digit is one block. Thus, 00-09 comprise one block, 10-19 compose another and so on. When keying in memory channels 00 through 09, remember to enter the leading zero.

When a station has been tuned in as desired in the Dial state, just press the two memory channel number digits and then D-m to store the Dial frequency and mode into that memory channel (operation remains in the Dial state).

Example: In the FM-W mode, assume that your favorite FM broadcasting stations are at 90.1, 95.6, 101.5, 103 and 104.5 MHz and that you wish to store them in memory channels 90 through 94. First, in he Dial state, tune in the station at 90.1 MHz using any of the tuning methods described before. Then press the "9" and "0" (white) keys, following immediately with the D-M key (lower right side of the main knob). Next retune the dial to 95.6 MHz and press "9", "1" and D-M. Then retune the dial to the next frequency and press the keys to store channel 92 and so forth for channels 93 and 94.

When finished the receiver will still be in the Dial state. Note that the memory channels (90-94) chosen are all in the "90's". The 80's 40' or even 00"s (00-09) could just as well have been used, but the fact that they are all in the same block will allow convenient channel stepping and scanning of these memories at a later time.

To recall the channels just stored, just press the MR key to enter the Memory state.
Notice that "CH 94" appears. Even if the dial had been returned to another frequency and mode, 104.5 MHz, FM-W would be recalled. To recall a memory other than the last one stored, just enter the memory channel digits on the keypad before pressing MR (of course the memory channel keyed in must have been stored at some past time).

End part 1 of 2.
 

Press and hold the DOWN or UP key for « second to scan the memory block. In this case, when more than one block of memories is stored, scanning will cover only the block containing the memory that is selected when the scanner is started. Later, when you have stored memories in different blocks, the tuning knob will allow selection of any of the occupied memories (irrespective of blocks).

There are two possible ways to return to the Dial state from the Memory state: one is shifting the receiving mode and frequency back to those last used in the Dial (just before MR was pressed) and the other overwriting the old Dial data with that of the selected memory. The first method is useful when you want to resume whatever you were doing before going to the memories. In this instance, just press the DIAL button. Use the second method when you want to continue in the same band or mode as the memory but need to tune around the memory frequency )or change the memory slightly). For this example, press the M-D (Memory-to-Dial) button.

Two-Way Communications Monitoring - The FM-N mode

To change modes from FM-W to FM-N (narrow), press the MODE button five times when in the Dial state. It is not possible to change modes in the Memory state.

Make sure that the grey ATT and AF SCAN switches are in their undepressed positions. Rotate the SQL control fully counterclockwise and then advance the VOL control to a comfortable level of background noise (or signal). Now turn the SQL control clockwise just to the point where the noise is silenced (Turning it further will reduce sensitivity to weak signals). The setting of the SQL control in this manner eliminates uncomfortable noise that would otherwise be heard when no signal is present on the receiving frequency while still allowing signals to be received.

Narrow FM is now the most commonly used mode for two-way business, military and amateur communications on VHF and UHF in most countries of the world. However, channel spacing (tuning steps), especially on frequencies below 200 MHZ, are often different from one area to another. 12.5 and 25 kHz steps are common in Europe with 5 or 10 kHz steps more common elsewhere. Above 200 MHZ wider steps (25 kHz or greater) are used so the 25 kHz setting should suffice. For now, unless you know the channel steps that are used in a particular band that you wish to monitor, use the smallest (5 kHz) steps. To select this option, press the STEP button (just below the displayed frequency) while watching the right side of the display for the selected step size indication. Your Yaesu dealer may be able to inform you as to which steps are utilized on certain bands, but in some instances this information may be unavailable in which case you can find out by experimentation using the 5 Khz steps, as mentioned later.

Now tune to a frequency range known to have two-way FM communications: 145 - 146 or 148 MHZ, 222 - 225 MHZ or 430 - 440 or 440 - 450 MHZ for amateur; 68 - 88, 134 - 174 or 400 - 512 MHZ for police, commercial business and marine. Mobile telephone also uses narrow FM, usually above 800 MHZ. The nature and degree of activity on these bands, as well as their limits, vary widely from one country to another so some exploring may be necessary. Note that two-way communications are distinct from broadcasting in that stations do not normally transmit constantly, so a frequency that is vacant one minute may be crowded with activity the next. The section on Limited Band Operation will describe the most convenient way to monitor the band.
The above frequencies are meant only as general guidelines to get started.

Use the tuning knob of DOWN/UP keys to scan around the band until you find a signal.
In some countries, constant-carrier repeaters are used. These transmit an unmodulated signal constantly which may open the squelch (a slight hissing may be heard) even when no voice may be present. Often, just listening to the frequency long enough will reveal who the users are. Also, signals in other modes may produce carriers or distorted sounds in FM-N. If this is suspected, try pressing the MODE button to check the other modes. if 12.5 kHz steps are used in your area, tuning in 5 kHz steps will result in some stations being impossible to tune in clearly. In this case just press the STEP button to select the right steps.

One other potential source of strange signals is intermodulation, which is the interaction of very strong signals in the receiver. This can cause signals to appear in the receiver that are really not on the tuned frequency at all. If you find such strong signals (which produce a full or nearly full-scale indication on the signal meter), press the ATT button. In the depressed position this button attenuates signals enough so that weaker signals may often be heard without interference from strong ones.

Scanning is similar to the FM-W mode described previously except that the AF SCAN button may be depressed to prevent the scanner from stopping on stations that have only a carrier (with no audio modulation). The memory functions are identical to those described in the previous section.

Airband Communications Monitoring - AM-W and AM-N

Practically the only AM (Amplitude Modulation) communications on VHF are in the aeronautical mobile band, from 118 to 136 MHZ using 100 kHz channel spacing (50 kHz in North America). Set the FRG-9600 to the AM-W mode, 25 kHz (the widest available) steps.

Communications are primarily between airport control towers and aircraft, with the AM wide mode being the best for general monitoring. Each airport generally has certain frequencies assigned to it so the memories can be put to good use - storing the local airport frequencies together in one block of memories. Note hat the transmissions are not made constantly so the band should be scanned to find the active frequencies in your area. See the Limited Band Scanning section below.

The SQL control for AM operation is set up in the same manner as for FM-N except that in AM the receiver is not completely quieted when the squelch is closed but only reduced in volume. This allows any weak signals that the scanner may skip to still be heard while reducing noise to a comfortable level. The AM-N mode may provide better reception of weak signals or those having interference from nearby frequencies. However, fidelity will be reduced so the AM-W mode should be used whenever possible. Tuning steps for AM-N are much finer than AM-W so it is generally most convenient to tune in stations first in AM-W before switching to AM-N. The SQL control should be reset as required whenever changing modes.

Single-Sideband (SSB) Communication - LSB & USB modes

SSB has been used for amateur and military communicators for many years because of its greater efficiency, providing greater range with lower power than FM-N and is now being experimented with for business communications at VHF and UHF in the form of ACSB (Amplitude Compandored Sideband). Typical (amateur) frequencies to monitor for SSB activity are 144 - 145 MHZ and 430 - 440 MHZ. Military SSB frequencies are harder to pinpoint but may be found by scanning, particularly around 136 - 144 MHZ in some areas. ACSB has not, as of this writing, been assigned any specific frequencies but experiments are being carried out in the VHF business bands mentioned earlier for FM-N. ACSB signals are distinguishable by a weak, high-pitch "pilot" tone.

SSB signals require very careful fine tuning provided by the fine (0.1 kHz) steps and the tuning knob. When the stepping buttons or scanner is used to locate SSB signals, some fine tuning with the knob will generally be necessary to tune the signal clearly (so the voice sounds normal).

The majority of SSB signals at VHF and UHF are sent in the USB (Upper Sideband) mode and this should be the one normally selected for monitoring. If you find a signal that sounds like SSB but cannot be tuned clearly, switch to LSB and retune slightly.

The SQL control may be set as for FM-N and signals will still be audible at reduced levels when the squelch is closed. However, when tuning around for weak SSB signals it is best to keep the squelch open (SQL fully counterclockwise) since there is no carrier in SSB to keep the squelch open during pauses in speech.

Radio telegraphy (CW) stations may also be monitored with the FRG-9600 using either the USB or LSB modes. Amateur CW signals may be found with and just below the frequencies indicated previously for amateur SSB.

Limited Band Operation

Practical use of the scanner in any mode generally requires that the limits of the scanning range be set to correspond with the particular frequency band of interest. This is easily accomplished with the FRG-9600 for any desired band, using two adjacent memory channels and the Dial. Not only are the scanning limits set, but also the tuning limits of the main dial: the receiver is actually programmed to behave like a limited band receiver.

The following example uses the procedure for the FM broadcast band between 88 and 108 MHZ but the same procedure may be used in any other mode or frequency range.

First select the desired mode (FM-W for this example) and tune the Dial to the high band edge (1087 MHZ) using the keypad (press 1,0,8,0,0 and Dial), the UP/DOWN buttons or the main knob. Then store this in any memory channel whose number ends in "1" (Ch 01 for this example) by pressing 1,0 and D-M.

Next tune the dial to the low edge (88 MHZ in this example) and store this in the next lower memory channel (Ch 00) by pressing 0,0 and then D-M. Only Chs 00/01, 10/11, 20/21 etc. may be used for limited band scanning.

Now to start limited band scanning, press M-D followed by the DOWN or UP button, holding this button in for « second. If the DOWN button is used to start, the scanner will begin at the high band edge (108 MHZ) and scan to the low band edge (88 MHZ) before jumping back to the high edge. If the UP button is used to start, scanning will begin at 88 MHZ and work up to 108 MHZ before jumping back to 88 MHZ.

Note that the highest frequency is stored in the higher numbered memory first and that the receiver is operating on the lower numbered memory at the instant the M-D button is pressed. If the highest frequency is stored in the lower numbered channel, the limited scan feature will still operate and the UP/DOWN buttons will correspond with the direction of frequency change but it may be more difficult for you to remember. However, scanning will always be between the memory number selected when the M-D key is pressed and the next higher-numbered memory so if the scanner does not loop within the desired range, you may have started it with the wrong memory. If nothing is stored in the next higher memory, the scanner will not be limited.

To deactivate limited scanning press the DOWN or UP button momentarily. Operation will be in the Dial state but all tuning with the main knob or scanning with the DOWN/UP buttons will be limited to the present band.

To escape from limited band operation use the keypad to enter another (occupied) memory channel followed by the MR button. Otherwise, simply enter another frequency and press DIAL.

Once the desired band limits are stored properly in the memories, limited band operation between those memories may be restarted at any time thereafter without the necessity of leaving the Dial state just by pressing M-D and the DOWN or UP buttons.

Priority Channel Monitoring

This feature allows periodic checking of one frequency for activity while tuning around or listening on another frequency or mode. When a signal appears on the priority channel reception will automatically shift to that frequency. Priority monitoring is especially useful when waiting for emergency police or fire calls while listening to other stations.

Priority monitoring can be activated in either the Dial or Memory state, but will remain active only while receiving in the state.

Before activating the priority function, tune the Dial or select the memory channel for the desired frequency (and mode) and set the SQL so that the noise is just silenced. Press the PRI button so that the "PRI" will appear to the left of the frequency display (with "DIAL" if in the Dial mode) indicating the priority function is now active.

Frequency and mode may now be changed as normal, as long as the state (Dial or Memory) is not changed. If receiving on the Dial, all buttons and controls can be utilized except the MR button (which will cancel priority operation and shift reception to memory). If in the Memory state, the tuning knob, DOWN/UP buttons and the D-M button may be utilized normally; the other buttons will be inactive or will cancel the priority checking. The receiver will jump to the priority frequency (and mode) every few seconds to check for activity. When a signal appears on the priority channel strong enough to open the squelch, the receiver will jump to the priority channel and remain there.

Limited band operation may be combined with the priority function by first setting up limited band operation as described earlier and then setting the priority channel on the Dial (it can be recalled from a memory with M-D, if desired). Once the priority channel is set in the Dial, press MR and use the main Knob to select the (prestored) memory on which to start limited band operation. Then press Dial and PRI to start priority checking, followed by M-D and DOWN or UP to start limited band operation.

The priority function is inactive while frequency scanning is activated but will resume when scanning is stopped manually.

Priority monitoring may be canceled by pressing the PRI button again but this will set the receiver to the priority channel. If this is not desired, use the DIAL and MR buttons to momentarily change state, canceling priority checking but saving the current receiving frequency.

Clock/Timer Operations

The clock/timer functions are displayed by pressing the CLOCK button which will then cycle through the different functions as described in the "Front Panel Controls" section. Reception will not be affected, although the tuning controls will be disabled. Press the DIAL or MR buttons at any time to cancel the clock/timer display and return to the regular frequency display.

1. Press the CLOCK button once to display the clock time. This is in 24-hour format, so add 12 hours after noon. To reset the clock, key in two hours digits (with leading zero if before 10 AM) and two minutes digits (again including zeros if needed). Then press the blue TIME SET button at the exact minute.

   The automatic power on/off timer in the FRG-9600 requires that the power switch be on (VOL control clockwise out of the click-stop) at all times when the timer is activated. Therefore, the OFF timer must be set to allow the timer to switch the receiver off and only then can the ON timer be used (to switch the receiver back on automatically within the next 24 hours). If the power is manually switched off by the VOL control, the OFF time will be deactivated (at least for the next 24 hours) and thus so also the ON timer. See the example below after studying the next steps.
   
    

2. Press the CLOCK button again to display the timer ON time ("ON" will blink on the display). This may be set in the same manner as the regular clock as described in (1). However, the ON timer will have no function unless the OFF timer (3) is also set.
   
    
3. Press the CLOCK button again to display the timer OFF time ("OFF" will appear blinking). This is also set in the same manner as above and must be set if the automatic timer is to be utilized.
   
    
4. Press the CLOCK button again to display the timer status (either OFF, OFF/ON or inactive). If the timer is not activated, only a decimal point will be displayed. After the ON and OFF timers have been set in steps (2) and (3), they may be activated while the timer status is displayed:

OFF Timer Only - Press (white) 0 off key. "OFF" will appear (non-blinking) on the display whenever the receiver is turned on and the receiver will turn off at the time set in (3).

OFF/ON Timer(s) - Press the 0 OFF key and then the CE ON key. "ON OFF" will appear (non-blinking) whenever the receiver is on and the receiver will turn off at the time set in (3) and back on at the time set in (2).

Use the following exercise as an example of timer operation. Assume your local time in now 7 PM and you're listening to the 10 minute VHF marine weather forecast on 162 MHZ (in a memory channel and shown on the display) which you would like to listen to every evening at this time.

Press CLOCK and check that the time display shows 19.00 (indicating 7 PM). If not, press "1", "9", "0" and "0" and then the TIME SET button. Press the CLOCK button again and check that "ON" is blinking at the upper right side of the display. Press the same five keys as in the previous step to set the ON timer to & PM also. Press CLOCK again and check that "OFF" is now blinking. Press "1", "9", "1" and "0" and the TIME SET button to set the OFF timer at 7:10 ON. Press CLOCK once more to enter the timer status mode and press "OFF" to activate the OFF timer, and "CE ON" to activate the ON timer (OFF and ON should now appear).

Press MR to return to the receiver frequency display (or press CLOCK again to return to the local clock display). When the forecast finishes at 7:10 PM, the FRG-9600 will shut off. If you do not turn the VOL control off, the receiver will automatically switch back on at 7 PM the next evening (and every evening thereafter).

If you turn the receiver off manually at any time, the timer will be deactivated (though all settings will be retained in memory as long as the DC supply is not interrupted). However, you can turn the receiver on manually after turning if off and the timer will resume its activity at the OFF time (7:10 PM in this example).

Perhaps it should be called an "OFF/ON" timer, but once accustomed to its behavior you should have no trouble making use of the timer for preset monitoring times.

Note: If the DC supply is interrupted for more than about 10 seconds, all clock/timer settings will be reset to zero/off.

Remote computer control

The CAT (Computer-Aided Transceiver) System was originally developed for external control of Amateur Transceivers by external personal computers. The simplified but powerful version of this system in the FRG-9600 offers vast potential for expanding the present functions of the receiver and adding new functions as may be desired for specialized reception techniques that are not possible with the receiver alone.

Physically, the CAT System is a serial data input port to the microprocessor in the FRG-9600 which will accept commands from an external computer via pin 3 of the CAT jack on the rear panel (pin 1 is ground). This control data must be sent in groups of five bytes, two stop bits and no parity at 4800 bits/sec. Within the groups of five bytes, each byte must be sent within 200ms of the last. Since most computers are not equipped with an output port that provides this format, Yaesu offers the FIF-series CAT Interface Units, the appropriate one of which should be installed between the computer and the receiver.

The CAT jack on the FRG-9600 also provides a sample of the AGC (S-meter) voltage at pin 5 and of the SCAN STOP (SCANNING=0v) status at pin 6. The AGC voltage can be converted into a digital pulse and used to inform the computer of the received signal level, either via the analog-to-digital converter in certain of the FIF-Units or by an external A-to-D converter, either outboard or located in the computer. The SCAN STOP status can be passed to the computer via a TTL-level digital input port. While neither of these connections is necessary for external control, they do provide a means by which the operating conditions of the receiver can be fed back to the computer allowing interactive ("intelligent") control by the external computer.

External Control Programming

There are just two types of commands used to control the FRG-9600: Frequency Set and Mode Set. While this makes programming very simple, the tremendous flexibility that these offer when wisely applied in a creative program should be borne in mind. The CAT Command Chart shows the format of these commands. Note that the bytes are actually sent from left to right, chronologically on the serial data line so that the Instruction byte is always sent first. For clarity, all bytes (8-but values)are depicted in their hexadecimal (base 16) forms with this indicated by an "H" appended to the last two digits.

Frequency Set Command

This command has an Instruction byte (1) of the value 0AH and has just one function: To change the receiving frequency to that encoded in bytes 2 - 5 of the command. The encoded byte values appear on the data line as they appear on the frequency display, with the largest frequency increments (hundred's and ten's of MHZ digits) in byte 2 sent first, and the smallest frequency increments (least significant digits, hundred's of Hz) in byte 5, sent last.

All of the frequency data bytes (2 - 5) are encoded with the total byte value (both digits) which is simply the hex number with the same two digits as the corresponding two decimal digits of the frequency. Byte 2 represents the hundred's and ten's (MHZ) decimal digits of the frequency, byte 3 the one's of MHZ and hundred's of kHz and byte 4 the ten's and one's kHz.
However, in byte 5, only the leftmost hex digit (high nibble) is used - for hundred's of Hz. The rightmost digit value is ignored, so use zero.

Note that the decimally converted hex value of each byte is not the same as the encoded value. For example, if byte 2 is 12H (hexadecimal), this represents a frequency of 120 MHZ, while the decimal conversion of 12H is actually 1 X 16 + 2 X 1 or 18 decimal. Make sure this point is clear before attempting to write a program.

Let's use this example to further illustrate this coding. To convert 65.4321 MHZ into the proper byte code for sending to the receiver, try this:

1. The 100's of MHZ is zero and the 10's of MHZ is 6, so byte 2 is 06H. If you are setting a frequency below 100 MHZ, don't forget to include the zero in the high nibble.
   
    
2. The 1's of MHZ and 100's of Hz digits are 5 and 4, so byte 3 is 54H (which is actually 5 X 16 + 4 or 84 decimal. Don't forget the encoding).
   
    
3. The 10's and 1's of Hz digits are 3 and 2 respectively, so byte 4 is just 32H (50 decimal).
   
    
4. Since the 100's of Hz digit is 1, byte 5 should be 10H (16 decimal) although any number between 10H and 19H would produce the same result, keeping the low nibble zero should make programming easier to understand.

Since byte 1 is sent first, the command to send to set the FRG-9600 to 65.4321 MHZ is, from right to left in the order of sending:

     0AH  06H  54H  32H  10H

Notice that the alphabetic digits of base 16 numbers "A" through "F" are never used in bytes 2 - 5 of frequency commands. Also, since the values of bytes 2 through 5 are only relevant to the frequency set command, they can be left unchanged (as "dummy" values) when sending mode commands. This can be used to advantage in programming.

Mode Set Command

This command has six types, one for each mode. Only Instruction Byte 1 is significant (although four more bytes must be sent as dummies - their values are irrelevant). The Instruction Byte must be 10H (16 decimal) for LSB, 11H (17 decimal) for USB, 14H (20 decimal) for AM-N, 15H (21 decimal) for AM-W, 16H (22 decimal) for FM-N and 17H (23 decimal) for FM-W. Again, the values of bytes 2 - 5 do not matter, but they must still be sent for the command to be recognized.

CAT control programs can be written in most any computer language, as long as the time between sending bytes does not exceed the m limit. In most cases the BASIC language will suffice. While it is not possible to give enough examples to cover all of the different dialects of BASIC, the following are a few possible ways using general BASIC statements to send commands to the FRG-9600. They will need to be modified for different brands of computers.

The first example illustrates use of the BASIC "OUT" command for single byte "port poking." This technique requires that the hardware interface include a port address decoder and parallel-to-serial converter that has been preset for 4800 bits/sec:

     REM  PTADDR = PORT ADDRESS OF SERIAL OUT

     OUT(PTADDR), &H0A:
     OUT(PTADDR), &H06:
     OUT(PTADDR), &H54:
     OUT(PTADDR), &H32:
     OUT(PTADDR), &H10:

Note that "&H" in the above example signifies for that BASIC statement that the following digits are a hexadecimal byte. In computers that do not have a hex number handling capability, the hex code must first be translated into decimal, in which case &H0A would be replaced with 10 (decimal), &H54 with 84 (decimal), &H32 with 50 (decimal) and &H10 with 16 (decimal). In either case the result of the command would be the same: To set the FRG-9600 to 655.4321 MHZ.

Another way to send the same command, when using a computer that is equipped with an RS-232C serial port and the FIF-232C CAT Interface Unit, is shown below (this example is for the Radio Shack Model 100, NEC PC-8201 or Olivetti M-10 portable computers):

     10  OPEN "COM:7N82NN" FOR OUTPUT AS#1
     20  PRINT#1,CHR$(10)+CHR$(6)+CHR$(84)+CHR$(50)+CHR$(16)
     30  CLOSE#1

The result would be the same as in the previous example: Set the FRG-9600 to 65.4321 MHZ. However, in this case the decimal equivalents of the properly selected hex digits have been substituted in the arguments. Note that this conversion is only necessary if the computer cannot accept hex arguments in the CHR$ command. If the conversion is necessary, make an array with the subscripts equal to the hex bytes and the contents equal to the associated decimal byte.

If the FRG-9600 is actively scanning frequencies via the internal scanner when the command is sent, it may be ignored. Internal scanning should be halted before external commands are sent (of course, this does not affect scanning by your CAT program).

Using only the main CAT serial input command line you should have no trouble with simple programs, such as incorporating your own memory banks and blocks, referencing the frequencies to station call-signs and automatically selecting the most popularly used mode for frequency range in your area.

When the S-meter and scan stop status lines in the CAT system are also used in programming, the external computer has some indication from the FRG-9600 of the results of commands it has issued: Especially, whether or not a signal is present on the frequency and how strong it is. This information can be used for programming just about any type of automatic scanning system, limited only by the imagination of the programmer.

              Byte No   1    2    3    4    5    Function
              Freq Set  OAH  NNH  NNH  NNH  NNH  See   below
              LSB       10H  X    X    X    X    Lower Side-Band
              USB       11H  X    X    X    X    Upper Side-Band
              AM-N      14H  X    X    X    X    AM Narrow
              AM-W      15H  X    X    X    X    AM Wide
              FM-N      16H  X    X    X    X    FM Narrow
              FM-W      17H  X    X    X    X    FM Wide

Notes:

1. Instruction Byte sent first: determines nature of command.
   
    
2. "NNH" values are hexadecimal codes for frequency data, explained in the text.
   
    
3. 3. "X" signifies "dummy" byte: Values are unimportant but must be sent to fill command to 5 byte format.

Memory Backup Information

Mode and frequency data is stored in the FRG-9600 by a lithium backup battery which has an estimated lifetime of at least five years. During that time if it is necessary or desirable to clear all of the stored data, use the following procedure:

1. Rotate the VOL control fully counterclockwise to switch off the receiver. Remove the power plug from the 13,8 VDC jack on the rear panel.
   
    
2. Remove the two screws on either side of the top cover and carefully remove the cover by lifting the back edge slightly while sliding the cover toward the rear. It is necessary to slide the cover back about 1 cm to disengage the internal spring clips before pulling the cover away (gradually, to avoid straining the speaker wires).
   
    
3. Locate the miniature (backup on/off) slide switch just behind the top right-hand corner of he front panel and set this switch to the right. Wait about 30 seconds and then return the switch to the left (if you desire to continue the memory operation).
   
    
4. Replace the top cover by first sliding it from the back to the front so that the two mounting clips on the inside of the cover catch on the internal frame and then replace the four screws. Reconnect the DC power.

If the memory backup feature begins to fail, see you authorized Yaesu dealer for installation of a replacement backup battery.

FIF-232C CAT system interface

Description

The FIF-232C is a TTL-to-RS-232C level adapter which allows external control of Yaesu CAT System transceivers and receivers by a personal computer. The FIF-232C converts between the 0/+5 volts at the CAT jack of the radio and the +15/-15 volts used by IEEE-standard RS-232C serial ports commonly used on personal computers. An opto-isolator in each data line of the FIF-232C enhances immunity to noise.

Software is not provided with the FIF-232C, but programming information is provided in the CAT System chapter of this manual.

This unit contains the following:

                FIF-232C Interface Unit            P/N D3000307

                Radio-to-FIF Control Cables             P/N T9204640
     Standard 6-pin DIN plug for FT-980, -747GX, -767GX, -736, -990, -1000, FRG-8800 &
-9600

                Spare Fuse (0.5A)                  P/N Q0000001

Interconnections

Before connecting the FIF-232C, make sure the power switches on the radio and the computer are both off. Do not connect the AC power cord of the FIF-232C to the wall outlet until after all connections have been made.

Connect the appropriate supplied connection cable between the radio and the FIF-232C, and connect your RS-232C cable between the FIF-232C and your computer. The RS-232C cable for connection to the computer is not supplied with this kit, and must be obtained separately (see your computer dealer).

After all connections have been made, switch on the radio first, followed by the computer and finally connect the FIF-232C to the wall outlet and switch it on. Your external control program may now be loaded into the computer.

Polarity Selection & External AGC/PTT Connections

The FIF-232C is set at the factory to provide output signals in the opposite polarity from the input signals. Should your computer require that the interface output and input signals be the same polarity, you can reconfigure the FIF-232C by a small internal slide switch on the pc board.
When this switch is set to position 1 (nearest the power transformer), polarity is inverted. Simply move this switch to position 2 to set the input and output polarities the same.

The CAT System uses only the TXD and RXD lines of the RS-232C bus for data transfer. However, the small jack on the side of the FIF-232C provides access to the AGC and PTT signals lines of some radios, for external A/D conversion of the receiver AGC and transmitter control. Most radios have A/D conversation and CAT PTT control built in and accessible through CAT commands, so these lines are not needed for all models.

End part 2 of 2.