The correct name for this is the "FM tuner", although it is often known, incorrectly, as the FM1.
(The true FM1 came before the 22/II series and was an adjunct to the QC-22 control unit.)
The "FM tuner" is part of the Quad II/22/AM setup, needing to be powered by the 22 control unit.
Text courtesy: Esmond Pitt http://www.telekinesis.com.au/wipv3_6/page2/show.jsp?id=249534&db=Entries
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