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Extended range for DJ-500T
Remote microphone and speaker
DJ-500E all freqs
Adjustment points for DJ-500TE

 

 

Modifications for the Alinco DJ-500 T

Expanded RF
 

 1- Take out battery and antenna.
 2- Take out screws from the case 9 3 long & 2 short )
 3- remove green component per drawing.
 4- Reassemble the radio.
 5- Reset the radio. ( Reset switch is located below the PTT Switch

Check that you have the new frequencies then reassemble the radio.

You can now program
130.00 MHz to 169.995 MHz
340.00 MHz to 379.995 MHz
420.00 MHz to 469.995 MHz
870.00 MHz to 899.995 MHz

 

 
Extended range for DJ-500T
 
     

This mod is for the alinco dj-500t, if you have little or no soldering experience do not !!! repeat do not try this mod on your radio. It is necessary to remove a chip resistor from the cpu board.

Tools you will need:
# 0 phillips screwdriver
25 watt soldering pencil,
Exacto knife.

I received a schematic and board layout from alinco free. Phone 1-213-618-8616. or send a sase to me at : bryan todd 318 aldrich road howell, nj 07731 and i will send you a copy of the board layout.
 
  1. Remove the battery pack
  2. Remove 3 screws from the back of the radio
  3. Remove 2 screws from the bottom (front panel side)
  4. Split the case carefully.
  5. Put the radio face down on the table with the top away from you. The speaker at the bottom.
  6. Find the "d" shaped gold pads under the speaker on the right side of board.
  7. The chip resistor is two pads up from the "d" shaped ones. The next steps can cause great illness to the radio !!!!!
  8. Very carefully heat one end of the chip and pry with knife.
  9. Then heat the other end and repeat until resistor is off the board.
  10. Hold the battery pack in contact with bottom of radio, turn on radio, press the reset button with toothpick (hole under ptt switch).
  11. Check that you have the new frequencies then reassemble the radio.

You can now program
130.00 MHz to 169.995 MHz
340.00 MHz to 379.995 MHz
420.00 MHz to 469.995 MHz
870.00 MHz to 899.995 MHz

Since you have the soldering iron hot you can build a nice accessory.
 

 

 
Remote microphone and speaker
 
     

To make a cable you have to buy:
1/8" stereo plug "rs #274-284"
1/8" to 3/32" stereo adapter "rs # 274-373"
10 k ohm 1/4 watt resistor "rs # 271-1335"
10 microfarad 35 volt cap "rs # 272-1013"
Mate plug for your spare microphone.
Plastic mini box.

I made one with a 8 pin standard mic plug so i can use my spare hand mic in the car with a 6" speaker.

Speaker mic connections:
 
shell      ground
tip        rec audio
ring       ptt & audio in.

Connect shield, ptt common and speaker common to the shell. Connect speaker plus to the tip. Connect a 10k ohm resistor and 10 microfarad cap to the ring. connect the ptt switch between the shell and the 10k resistor. Connect the mic plus to the 10 microfarad cap. Now you can use a real speaker and real microphone. That will also work for packet but use a .1 microfarad cap not 10 mf....
 

   |_____| SHELL
     | |
     | |
     |-|
     | |  ring
     |-|
      V   tip

 

 

 
DJ-500E all freqs
 
     

Hallo everybody,
To extend the frequency-range of the dj500e, just cut two risistors.
The resistors are R61-R63.

The european version has the risistors in the following position:

BP1 and BPX.

The open version needs no!! Resistors. So cut them off.
They are located on the printboard with the speaker and microphone.
If you have the diplay on the left, you will look on the board and see them in the upper right corner.....
There are two resistors with the numbers 000 (zero zero zero) on it.
Actually they are no resistors, just a wire, but in smd it looks like a resistor. so get them off the board and do a reset !!!!
The reset is very important because otherwise you will not get the new freq-range....

You got it????
Hopefuly, if not, leave a msg in bbs DB0AHA.
Greetings from DL1BEQ frank
Rmks: This modifycation let you loose your warrantee, and also may cause problems with your national communicantions authority.

 

 
Adjustment points for DJ-500TE
 
     

 
Item Adjustment Point Adjustment Method Spec
5 volt line voltage VR605 Turn VR605 so that the voltage of 16 pin og IC601 should be 5.1 V. 5.1 V ±0.1 V
VCO P/D voltage L401 (RX VCO) (VHF)

L501 (TX VCO) (VHF)

L406 (RX VCO) (UHF)



L504 (TX VCO) (UHF)		 Adjust L401 so that the voltage of C362 (+) is 1.5 V.

Adjust L501 so that the voltage of C362 (+) is 2.0 V.

DJ-500E
Adjust L406 so that the voltage of C343 (+) is 1.1 V.
DJ-500T
Adjust L406 so that the voltage of C343 (+) is 1.9 V.
DJ-500E
Adjust L504 so that the voltage of C343 (+) is 2.1 V.
DJ-500T
Adjust L504 so that the voltage of C343 (+) is 3.0 V.
 		 1.5 V ±0.3 V
(145 MHz)
2.0 V ±0.3 V

1.1 V ±0.2 V
(435.0 MHz)
1.9 V ±0.2 V
(445.0 MHz)

2.1 V ±0.3 V

3.0 V ±0.3 V
Frequency TC209 Set the unit in the transmission mode at 435 MHz (DJ-500T: 445 MHz) and adjust TC209. 435 MHz ±500 Hz
(445 Mhz ±500 Hz)
VHF power output VR201

VR204		 On "Hi" position, turn VR201 for 6.6 W output at 145.0 MHz 13.0 V.
On "Lo" position, turn VR204 for 0.6 W output at 145.0 MHz 13.0 V.		 6.5 W ±0.5 W

0.5 W ±0.1 W
UHF power output VR202

VR203		 On "Hi" position, turn VR202 for 5.6 W output at 435 MHz 13.0 V. (DJ-500T: 445 MHz 13.0 V)
On "Lo" position, turn VR203 for 0.6 W output at 435 MHz 13.0 V. (DJ-500T: 445 MHz 13.0 V)		 5.5 W ±0.5 W

0.5 W ±0.1 W
VHF deviation VR604 Input a signal of 1 KHz/50mV into the MIC jack and adjust VR604 so that you obtain 4.8 KHz/Dev in the transmission mode. 4.8 KHz
±0.2 KHz
UHF deviation VR601 Input a signal of 1 KHz/50mV into the MIC jack and adjust VR601 so that you obtain 4.8 KHz/Dev in the transmission mode. 4.8 KHz
±0.2 KHz
Subaudibel tone deviation (DJ-500T) VR1 On the "ENC" mode at 449 MHz, turn VR1 so that the deviation is 0.8 KHz. 0.8 KHz
±0.1 KHz
1750 Hz tone burst deviation (DJ-500E) VR1 Pressing Tone button at 435.0 MHz, turn VR1 so that the deviation is 3.5 KHz. 3.5 KHz
±500 Hz
DTMF deviation VR1 Pressing [1] key at 435.0 MHz (DJ-500T: 445.0 MHz), turn VR1 so that the deviation is 3.3 KHz. 3.3 KHz
±500 Hz
UHF receiving sensitivity (SG output: Mod 1KHz, 3.5KHz/dev) TC201
TC202
TC203
L602
L603
L607
  1. Set the frequency at 435.0 MHz (DJ-500T: 445.0 MHz) and turn the squelsh control OFF.
  2. Adjust TC201, TC202, TC203, L602 and L603, so that the RX sensitivity becomes macimum.
  3. Adjust L607 so that the audio output becomes maximum.
 (12 dB SINAD) (EMF) under -6 dBµ
VHF receiving sensitivity (SG output: Mod 1KHz, 3.5KHz/Dev) L221
L222
L223
  1. Set the frequency at 145.0 MHz and turn the squelch OFF.
  2. Adjust L221, L222 and L223 so that the sensitivity becomes maximum.
 under -6 dBµ
S-meter (SG output: +6 dBµ EMF) VR603 (VHF)
VR609 (UHF)		 Turn VR603 so that the [1] begins to light.
Turn VR609 so that the [1] begins to light.		 +4 to +8 dBµ
Squelch sensitivity VR606
  1. Connect the antenna terminal to the chassis ground and set the squelsh volume to the 10 o'clock direction.
  2. Turn VR606 to set the threshold point.
 Threshold point

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