[R-390] Proper Muting

[Roy Morgan]

At 09:55 AM 7/19/03 -0700, Joe Foley wrote:
>Yup, that's all there is to it, test it by grounding
>either of the terminals to make sure the relay is
>working, it should mute the LINE and LOCAL amplifiers
>and ground the antenna input.  You may still have to
>reduce the RF GAIN while transmitting though, this
>will show on your modulation monitor(scope).


Notes:

1) The relay is operating on 6.3 volt filament current supply and uses 
about 40 ma of current. One side of the circuit is ground.  The think is in 
MUTE mode when the terminal 9 on TB 103 is grounded and the mute relay is 
energized.  The MUTE relay is in the audio deck.  (The Antenna relay is 
also energized at this time.)

2) The entire radio ahead of the audio amplifier stage is operating normally.

3) The antenna connections (both UNBALANCED and BALANCED) are grounded, but 
strong signals from transmitters will get through, as Joe notes above.

Roy

- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
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