[R-390] Carrier Level Meter full deflection

[Larry H]

Hi Gary,  Insufficient c/l meter deflection is usually caused by low gain
in the agc amp circuits or bad caps on the agc line.  Try replacing V508
and V509.  The caps that usually cause this are C547, C548 and C551, but
there are many other problems that can cause it.  See Charles Steinmetz agc
diagnosys document on our website and my agc diagnosys part 2, both in the
'repair tutorials' section.

Regards, Larry

On Fri, Sep 15, 2023 at 9:24 AM <gary.biasini at shaw.ca> wrote:

> Larry,
>
>
>
> Thanks.  Manfred Antar advised me privately to adjust the pot for the
> carrier level meter.  While that brought the meter to zero, it barely
> deflects 30% even on the strongest local BCB stations.  As well, on MGC,
> the needle now goes negative.
>
>
>
> I will replace V506A and check the value of the plate resistor.
>
>
>
> Thanks for your input.
>
>
>
>
>
> *From:* Larry H <larry41gm at gmail.com>
> *Sent:* Friday, September 15, 2023 12:17 AM
> *To:* gary.biasini at shaw.ca
> *Cc:* R-390 at mailman.qth.net
> *Subject:* Re: [R-390] Carrier Level Meter full deflection
>
>
>
> Hi Gary,  One possibility is that V506A is very weak or dead or its plate
> resistor R549 is open or a very high value.
>
>
>
> Regards, Larry.
>
>
>
> On Thu, Sep 14, 2023 at 5:59 PM <gary.biasini at shaw.ca> wrote:
>
> Good evening,
>
>
>
> I am hoping for some help on this.  On EAC S/N 3122, upon turning on the
> radio, even without an antenna attached and not tuned to any signal, the
> carrier level meter deflects fully in both AGC and MGC mode.  The AGC
> appears to be working because, on strong signals, the sound at the output
> is
> not as strong as on MGC.
>
>
>
> Any thoughts as to what may be causing this issue?
>
>
>
> Thanks in advance.
>
>
>
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