[R-390] CL-80

[Gordon Hayward]

I put mine in an outboard box and plug the 390-A into it using its switch.
That also protects the 390 power switch which has caused others grief in
the past.

The box also houses the additional detectors running off the IF output.  I
added a dual product detector with the BFO in quadrature for 'SSB stereo',
a precision rectifier AM detector and a PLL FM detector.  Of all of these,
the product detector is the most useful.  In stereo' mode, there's little
effect on the SSB signal but the noise is more like a waterfall and is a
lot easuer to listen through.

Cheers, Gord VE3EOS