[Milsurplus] Re: [ARC5] Re: Getting an "ARC-5 " Transmitter Running

[David Stinson]

Unserviceable but Repairable wrote:
> 
> It's been years since I hacked into one of those.  Mebbe 40+.  But I thot
> the "antenna relay" was just selected by the tx control box & not the
> key line.

In the original design, the "selector" relay and the antenna relay
were activated to "select" the transmitter to be used.
Keying happened in the modulator unit, where the B+ main was
keyed by a relay.  The "selector" relay (the one under the chassis)
applies B+ to the oscillator and grounds the PA cathodes.
So, by happy chance, it makes an excellent "keying" relay for
those folks who do not have the entire set-up.

73 DE Dave AB5S