Galaxy FC-347/FC-390 install
on a PRESIDENT WASHINGTON (8719)
(from Rabbit Ears)



Just installed a GENERAL FC-390 (the same as the Galaxy
FC-347) digital frequency counter to a President Washington
base station (8719) unit.

PC board is a (PC-385) Yup, it is the same board as the
President Grant, Cobra 142GTL, and Realistic TRC-490 among
several others. This is lengthy!

1. Unpack your frequency counter from it's box and set
aside the "pigtail" supplied to hardwire it to chassis
without the plugin in the back. Set this aside for later.

2. You'll have to make a very simple modification to the
frequency counter as to make it work on your Cobra/Uniden
unit. Okay, remove the four screws on the sides of the unit
and open the thing up and open up the metal box and take
the time to read the pc number. It should read EPT210014C
ot EPT210014D. The (C) model has ONE jumper to soldier
together on the top of the PCB, however the newer (D) model
had TWO jumpers to soldier together on the bottom of the
circuit board. You'll have to unsolder the metal case from
the PCB to get to the its bottom.

3. Use a very small wire to bridge the jumpers on both
models. NOTE: on model EPT210014D you'll have to resolder
the metal box to it after you are done. Re assemble the
unit.

4. Wiring the unit to your set: (your radio already has
the bottom and the top off) Drill a 1/4 inch hole in the
back of your radio for your wires.

A. Get your pigtail now and inspect it for a co-ax, that is
the VFO wire. Okay find TP-1 and TP-2 that's your VFO
output...find where the test points are soldiered to the
set's pc board. and mark it TP-1 and TP-2...Get a 68Pf
ceramic capacitor to soldier in series to the inner wire
of the VFO coax and TP-1. Now, solder the shield to where
TP-2 is.

B. Now look at your wires again for a BROWN one, that is
ground..solder it to the ground foil on your pcb.

C. Find your RED wire and solder it to pin #1 of your
MB3756 chip bolted to the right side of set it is a 8 pin
sip chip. Please use a VOM with the set turned on Pin #1
should read just over 8VDC.

D. (turn your radio on) Now find the ORANGE wire that's the
USB B+ wire turn your set's AM USB USB selector switch to
USB. There are two wires coming from the selector switch
a yellow one and a green one. Check which one has voltage
(just over 8VDC) and soldier your ORANGE wire to the pcb
where where the wire that showed voltage is connected to.
E. Now you are about done. You should have only a yellow
wire left to go. Switch your set to LSB and find the green
or the yellow wire that has voltage (8.0VDC) and connect
your wire on the pcb where it is soldiered to.

Turn radio off and connect your frequency counter and watch
it go. This repair is at your own risk, however it worked
splindidly for me.

Note: There are some President Grant mobile units that have
DUAL finals and different PCBs; however the VCO works the
same as the President Washington. This is the 34MHz signal.
As I remember check test points around the VFO for the 34MHz signal.


Good Luck,
Rabbit Ears



TEHNICHAL BULLITIN: FC-347 / FC-390
Re: Frequency drift on all settings AM, LSB, and USB.
SOLUTION: Move red wire on harness supplied from pin #1
on voltage regulator to pin #2. Reason: The frequency counter was slightly drawing down
the voltage on the VCO, causing frequency drift on some
sets. Please effect the changes.

Happy Holidays
Rabbit Ears

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