I just picked up what appears to be a Trio (Kenwood?) model SM-1
tube-type HF preselector. I can dope it out for the connections to fil
and B+ but can anyone provide type of tubes used? They are both 7-pin
miniature and the fils are pins 3 and 4. Could be 6BA6 or 6BZ6, maybe?
Its a 2-stage device and may be a converter instead of a preselector?
Two sets(decks) of coils and compression trimmers. The vintage is said
to be in the 50's but can't confirm. The size is about like a Heath
VF-1 VFO and typical of early Trio/Kenwood gear. Logo says Trio but
unlike any Trio logo I've seen on their early ham gear. There is a
picture and reference to it being a preselector on a JA's website but no
joy on anything else. Any info would be appreciated. de K3HVG