Help on weak modulation for a Heath SG-8 siggen

[Bernie Murphy]

I have an SG-1 (I think all the models are basically the same).  I never use 
the audio oscillator.

Assuming the tubes are OK, you might have some bad caps. Anything that looks 
"gooey" is suspect. As you probably know, sometimes the only way to find bad 
caps is to replace with new ones.

Also, carbon resistors tend to change value with time (usually, the 
resistance goes up) and that can cause challenging problems.

If you are still stuck, I can scope my SG-1 and give you some signal levels 
at some key points.


Regards,
Bernie, VE3FWF, Ottawa, Canada




----- Original Message ----- 
From: "Ray LaRue" <rlarue at SWFLA.RR.COM>
To: <HEATH at LISTSERV.TEMPE.GOV>
Sent: Saturday, November 12, 2005 8:45 AM
Subject: [HEATH-TEMPE] Help on weak modulation for a Heath SG-8 siggen


>I purchased a clean, used SG-8, the RF output is fine, but the modulation 
>is very weak.  The audio oscillator works but on a scope it looks like 
>about 5 or 10%. It can barely be heard thru a receiver.  The manual isn't 
>much help in troubleshooting the problem.  Voltages look nominal.
>
> Anyone have any experience with it, that could offer some suggestions?
>
> Your attention is appreciated.
>
> 73,
> Ray, W4BYG
> Naples, FL
>
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