[ICOM] IC 751 problem

[Gary Fiber]

Shaun,

Just get to the PLL board.. Probably easiest to remove the board. 
Open the VCO can, has 4 holes in the top of it and its soldered in 
place so some solder wick will be needed,
Once you have the lid off take a good look as there is likely wax 
inside. Scrape up as much as you can of the wax as you can from 
around the caps and where they go through the circuit board.. The 
trick is to be able to remove and replace the caps without wax 
running into the hole the cap solder into.

Once you have the raps replaced you will want to add some new wax. 
Don't allow wax to run over the new caps. Many use an old soldering 
iron tip to remelt the wax
Once done grab up your DVM and attach it to the test point, tune the 
dial to the proper place and set the voltage for the first cap, 
repeat for the others and you should be done.

The wax keeps the microphonic problems down from the  VCO box.

Gary K8IZ

At 02:18 AM 9/3/2009, you wrote:
>Hi Gary
>
>Thanks for the information on how to fix the IC 751
>
>Regard
>
>Shaun Palmer VK6FSAP
>
>-----Original Message-----
>From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
>Behalf Of Gary Nichols
>Sent: Thursday, 3 September 2009 6:50 AM
>To: 'ICOM Reflector'
>Subject: Re: [ICOM] IC 751 problem
>
>Sounds like the VCO trimmer caps need replaced...the original plastic caps
>were notorious for causing that issue.
>
>-----Original Message-----
>From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
>Behalf Of shaun Palmer
>Sent: Wednesday, September 02, 2009 6:31 PM
>To: icom at mailman.qth.net
>Subject: [ICOM] IC 751 problem
>
>Hi
>
>
>
>My IC 751 is distorted on RX and when I TX on 80m and 40m. 40m is worse than
>80m.   I there is no distortion on 20m.  I need some help where to find the
>problem.
>
>
>
>Regard
>
>
>
>Shaun Palmer  VK6FSAP
>
>
>
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>
>----
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>Icom Users Net: Sundays, 1700Z, 14.316 MHz
>Icom FAQ: http://www.qsl.net/icom/
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Gary Fiber K8IZ
GROL PG-19-6691
Washington State Resident