[Boatanchors] FW: HRO-60 Mystery Plug-in Chassis

[D C *Mac* Macdonald]

One of the HRO-60s I have acquired came with a plug-in
chassis that has a transformer, three tubes (6BY6, 6Bc7,
and 12AU7) plus a potentiometer on the top side.

Does anybody have any ideas what this might be?


* * * * * * * * * * *
* 73 - Mac, K2GKK/5 *
* (Since 30 Nov 53) *
* Oklahoma City, OK *
* USAF, Ret (61-81) *
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