[Milsurplus] Unique BC-221 Conversion

[Hubert Miller]

I'd call it an unfinished project. The "Plate Voltage" lamp comes on when the B+ is delivered to an aux connector pin, not indicating when the B+ is applied to
the plates. The "ant. trimmers" are an odd touch too.
I guess this was intended as some kind of portable or emergency equipment, having the handle and the front cover. I'm very happy to see some people are
bidding on it, even though i sure wouldn't want it, so it doesn't just go the scrap metal bin.
-Hue

>His schematic appears to be incomplete. This looks like a typical 30's-40's MOPA diagram but he has two each controls for the osc and amp plates, yet there are only one cap in each. Also there are some apparent antenna trim controls on the top but nothing on the schematic. It goes straight to a link coupled output. Also there's a "plate current" bulb on the top, but not on the schematic.  Curious about that because the meter is switched between the two tubes, and there's no separate plate power-on switch. Looks like he only used the BC-221 cabinet, gutted the rest.

The keying, yes it puts a lot of V on the key, but many early Novice rigs used that. As long as you keep the cathode side to the lower (hot) contact on the key, chances of an accidental contact are small. Lived with this method of keying for years. Still do on some rigs!

Of course this does beg the question of what happened to the "real" BC-221.......
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