SB-100 help...

[Chris Trask]

On Tue, 15 Jul 1997, Alexander N. Gerli wrote:

> Hi,
>
> Further to my posting on the "dead" SB-100:
>
> Well, it ain't exactly dead any more. Suddenly, the receiver came to
> life. However, while I can achieve S9+20 readings for the calibrator
> signal, normal signals don't move the S-meter hardly at all. The
> receiver doesn't seem to be deaf; there's adequate sensitivity, and the
> alignment seems to be peaked pretty well.
>
> Could there be intermittent contact to chassis ground on any of the PC
> boards which I should particularly look for??
>
> I'd appreciate any hints and kinks you might be able to pass my way.
> I have the original manual, complete but taped profusely...
>

Sandy,
        I might start off by getting a can of tuner cleaner and carefully
cleaning the bandswitch, particularly the antenna tank section, which is
where your trouble is most likely occurring.  I bought a pristine SB-310
years ago, and had to go through this procedure before it worked properly.
I've also done it with intermittent test equipment, quickly solving the
problems associated with tarnished switch, potentiometer, and connector
contacts.  I once saved an otherwise perfect $350.00 HP8414A polar display
by spraying a $0.01 amount of cleaner into the $40.00 intensity control.

        Real radios glow in the dark.

                                          Regards,

                                          Chris

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