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To
do this mod, you have to follow all the rules.
1.) You've spent about 200+ bucks for this
radio, now go out and spend another 25 bucks on
what you will need to do this mod successfully.
You will need the following equipment:
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A nice soldering iron and a BRAND NEW TIP!
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Some Radio Shack 60/40 thin low rosin core
solder the good stuff
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Desoldering Braid (to suck up solder)
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Desoldering Pen (uses suction to suck up
solder)
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A decent maginumfying glass (you will need
this!)
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A damp sponge (to clean the soldering iron
tip with)
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A clean and clear workspace with plenty of
elbow room
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A small parts box of some kind to collect
parts (hehehe)
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A steady hand, tall glass of water and a
change of shorts when you get to the diode
section. (this was funny, my wife came into
the room and saw the radio in pieces and I
was sweating with my mouth open and was
drooling when I saw the diodes I needed to
unsolder) Now remember, the radio was
already disassembled and there was no
turning back. OH CRAP!
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PATIENCE! This mod took me nearly 4 hours to
complete.
Just a preview of your workspace in a couple of
hours!
I GOTTA REMOVE WHAT!
These diodes are about as small as the tip of a
lead pencil, you CAN do this if you want.
STEP 1
Orient the radio with it face down and the
antenna pointing away from you. This is the
orientation you will keep the radio at all times
unless otherwise directed to do so. (I used a
piece of felt to place the face of the radio on)
STEP 2
You should be looking at the back of the radio
at this time. Unscrew the antenna and pull off
the dial knob and place them in your parts box
for now.
STEP 3
Unscrew the antenna and dial knob ferrules (this
is the nut that holds the antenna connector to
the case).
*** WARNING *** The SMA Antenna ferrule
is held on with some kind of super glue in the
threads so you will need to work this nut loose
ever so carefully. Just a piece of information
that you may find useful, all the ferrules on
the radio rotate clockwise to tighten and
counterclockwise to loosen. Thus the old saying
(Righitie tightie, leftie loosie). I used a
jewlers screwdriver and a pair of needle nose
pliers and placed the tip of the screwdriver
into one of the notches of the SMA ferrule and
"TAPPED" ever so lightly until it began to move.
This requires time so take as much of it as you
need, no sense screwing up this mod before you
begin. It will work loose so take your time. You
might also want to remember that you will be
taking out the RF module board later and the SMA
connector must come out of the case so you will
need to remove the nut SORRY. The SMA connector
is also glued to the case but using the same
"TAPPING" method above, you will work it loose
(more on that subject later)
STEP 4
Once you have removed the ferrules in step 3,
you can remove the battery cover and batteries
from the radio to reveal two screws in the
compartment. Remove these screws and place them
in your box. Just a note, I taped the screws to
a post-it paper and labeled them so I knew where
the went when I was re-assembling the radio.
Next lift off the rear cover by prying the cover
from the front at the rear then up and towards
you (keeping in mind the orientation of your
radio as described).
STEP 5
You should now see the RF board (daughter board)
on top of the main board inside your Q7A. WHEW!
STEP 6
On the RF BOARD! there is one visible screw
located on the right side, see figure 1.4 below:
STEP 7
There are three points where the shielding for
the RF board has been soldered to the lower
board. One is in the lower left corner just
above the ferrite inductor figure 1.5 and along
the right side of the RF board next to the PTT
button figure 1.6 and in the upper left corner
near the blue assembly of the dial figure 1.7
Figure-17
Figure-15
Figure-16
Unsolder Figures 1.5, 1.6, and 1.7 with the
solder sucker and desoldering braid to wick up
any left over solder. Be careful not to melt the
plastic case in the procedure in figure 1.7.
*** WARNING *** ONLY, do a small spot at
a time. DO NOT OVERHEAT sections. If you don't
get all the solder in one time, don't worry, let
things cool down a bit and go back for more
later when it cools.
STEP 8
Once you have removed all the solder from the
above steps, lift gently with your FINGERS ONLY,
the rear of the RF board until the connector on
the RF board figure 1.8 dislodges from its
counter part on the main board, figure 1.9, use
your fingers only because of the surface mount
components which are located near the edge of
the circuit board, you don't want to pry off any
of them with the blade of a screw driver.
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Figure 1.8 |
Figure 1.9 |
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Once you have dislodged this connector, the RF
board will "Rock" clockwise just a little bit
and tap gently on the SMA connector at the same
time to dislodge it from the plastic housing
(remember, it's glued so be patient). DON'T TAP
TOO HARD, the RF board has inductor coils near
the SMA connector end that if they get jammed
into other parts of the radio could effect
performance later. BE GENTILE!
You should now have the RF board completely
removed at this time: Figures 1.10 and 1.11
shows both sides of this board
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Figure 1.10 Bottom View |
Figure 1.11 Top View |
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STEP 9
Remove the screw on the right hand side central
to the PTT, and FUNC button. And the one on the
left just bellow the little shield. DO NOT
REMOVE the two top corner ones they hold the LCD
assembly!!! See figure 1.12 for which screws to
remove.
Figure 1.12
STEP 10
Desolder the two speaker wires from the speaker.
Lift the bottom of the board out till the LCD
clears its mounts in the case and pull the board
out GENTLY so the rubber seal and the rubber
keypad is not dislodged. If they do, just re
insert them. See figure 1.13 for speaker solder
joints.
Figure 1.13
STEP 11
Turning this board over with the LCD now facing
you there is position for 7 SMD diodes marked A
or A2 on the right hand side just above the
central mounting point. All have to be removed I
had 4 in my radio! See figure 1.14
Figure 1.14
Figure 1.15
The easiest way that I have found of removing
the diodes without damaging them or the PCB
assembly is to heat one end / contact of the
diode with a custom tip I made (pretty ingenious
I think) figure 1.15 and using a desoldering
braid to wick up the solder and lift that end
with a small pointy screw driver (jewlers type
works good) **** NOTE **** You don't have to pry
the diode up, it just needs to clear the PCB a
fraction. Remember, DO NOT over heat the diodes
or the contact, this could cause the PCB trace
to lift off of the board, that would be a bad
thing.
Once you have removed the diodes, take a break!
You deserve it.
STEP 12
The re-assembly. The re-assembly is pretty
simple. Reverse the procedures. One point of
note is when you come to re-applying solder to
the RF board to the main housing. Be careful to
not apply too much solder so it leaks down into
the radio and also do not over heat ANYTHING!
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