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Open transmit for IC-761 transceiver

dennisissure

Member
Jul 21, 2009
2
0
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Hello and GM; I'm new to this site so please excuse any ignorance shown. LOL

I have an Icom IC-761 that I would like to make the mod for the open transmitter; however, the only information I find is cut R37 on the Front Marker Unit. That really doesn't tell me much........

I need to know how many covers to remove, what boards have to be removed and how many screws you know a detailed step by step procedure.

ALSO, if the tuner mod is made before the open transmitter mod will the tuner mod work or does the open transmitter mod have to be performed before it does?

One last question, my 761 has the 500 hZ filters, will the addition of either or 250 hZ filter/s make a whole lot of difference when using CW and trying to pull weak CW signals out?

Thanks in advance
Dennis K4CKD
 

Hello and GM; I'm new to this site so please excuse any ignorance shown. LOL

I have an Icom IC-761 that I would like to make the mod for the open transmitter; however, the only information I find is cut R37 on the Front Marker Unit. That really doesn't tell me much........

I need to know how many covers to remove, what boards have to be removed and how many screws you know a detailed step by step procedure.

ALSO, if the tuner mod is made before the open transmitter mod will the tuner mod work or does the open transmitter mod have to be performed before it does?

One last question, my 761 has the 500 hZ filters, will the addition of either or 250 hZ filter/s make a whole lot of difference when using CW and trying to pull weak CW signals out?

Thanks in advance
Dennis K4CKD

Do you have the operator's manual and service manual for that nice old Icom? Start there. But why butcher such a venerable transceiver?
 
Remove the bottom cover, locate the large, lone resistor marked R37 near the front center, (not far back from the face) and cut or unsolder one leg and shrink wrap in place.
DONE!
It's absolutely the quickest/ easiest mod I've ever done.

More info:

KB2LJJ Radio Mods Database

And, to make the tuner function on General Coverage:

Remove the top cover of the IC-761 and locate the tuner band switch unit PC Board which is the 2nd small PC board located
behind the antenna tuner preset unit.
On the board, locate J 7 and at that location, you will note a three (3) pin molex plug with a black, brown, and red wire
connected to it. Either unplug, remove, or clip the center brown wire coming from the plug. Carefully unplugging the wire and
placing heat shrink tubing over the end works very well.
This enables the tuner to be activated on GENERAL as well as the ham bands.

From: http://hamradio.online.ru/ftp3/All_ICOM_mods_from_mods_dk_in_ONE_file.pdf

73
 

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