Hi,

You can see one installed in a Mackay communications console in the
4th ed. of THe Radio Manual by Sterling & Monroe, 1950. Pages 511 to
553 are devoted to this console, including a fold-out schematic of the
Scott receiver itself (called an SLR-F). It was paired with a Mackay
128AV (15 - 650kHz, battery-powered)

Does this mean the RCH served as the audio output stage for the Mackay? I can
imagine a lot of military rx wer made with only "line level" or "diode load"
outputs, meant to feed RTTY decoders and the like, and the RCH wuld provide a
speaker audio driver for such rx.

If I'm reading the text correctly, position 2 was not used, but the
"Mixed" mode fed time signals to check the chronometer.

73, Alan