Re: {Collins} 75A-4 "Motorboating"



If he used the K7CMS AGC mod, then that is the problem.  It causes motorboating.  A much better AGC mod is the one published in Electric Radio by W1LSB.  Works better and no motorboating.

Mike WB0SND


> On Oct 16, 2017, at 10:00 AM, Richard Solomon via Collins <collins@xxxxxxxxxxxxx> wrote:
> 
> A friend of mine has a 75A-4 that was overhauled by Howard Mills several years ago.
> 
> 
> It has developed a problem: On CW and SSB there is only what I would call "motorboating"
> 
> on the signal. It's a low level, not enough to overcome the signal, but annoying just the same.
> 
> 
> This is not heard on AM, so I would suspect the Product Detector, but all the parts were
> 
> changed during the overhaul.
> 
> 
> Any thoughts or suggestions ?
> 
> 
> 73, Dick, W1KSZ
> 
> 
> Sent from Outlook<http://aka.ms/weboutlook>
> *** You are subscribed to Collins as sndtubes@xxxxxxxxxxxxxxx. If you wish to unsubscribe, or modify your preferences please visit https://mailman.listserve.com/listmanager/listinfo/collins ***
> 

Michael Marx
sndtubes@xxxxxxxxxxxxxxx
636-939-9190

SND Tube Sales
105 N. Division St.
Bonne Terre, MO  63628







This archive was generated by a fusion of Pipermail (Mailman edition) and MHonArc.