[ICOM] 745 CW problem

[Gary Fiber]

I had overlooked your original message Jim.
Most anything strange that happens to the IC-745 one should look at 
the reg board.
That little R1 - 4.7 ohm resister seems to change its value a lot. 
The change in the 8 volt supply will cause lots of weird problems.
Seems to me that circuit board is also in the IC-751 / A too.

Its acceptable to increase the wattage on that resistor. I think 
originally it was a 1/4 watt, we used to replace it with a 1/2 watt size.
That is a good find Jim.

Gary K8IZ


At 05:19 AM 3/23/2009, you wrote:
>After a lot of work, I finally could trace the problem in the 745 to R1 in
>Regulator Board, it was way up in value, several kohms, instead of the
>original 4.7 ohms.
>This caused the 8a voltage mentioned in the manual to drop about 1 volt and
>that blocked the keying / ALC circuit.
>I replaced the resistor, and as it is an old rig I replaced at same time the
>electrolytics on that board. Now the radio is working fine.
>If you have a radio where the delay for semi break-in in cw is not working,
>check that regulator.
>
>73 to all,
>
>--
>Jim, HK1N
>----
>Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
>Icom Users Net: Sundays, 1700Z, 14.316 MHz
>Icom FAQ: http://www.qsl.net/icom/
>To support QSL/QTH.net: http://www.qsl.net/donate.html

Gary Fiber K8IZ
GROL PG-19-6691
Washington State Resident