I came across a few sets that were made by a company call: MP Television. They were located in Fairfield, Conn.
I found these while researching MP Engineering Corp. - maker of audio gear back in the 40s, 50s and 60s.
I have three different models. I also have the original, hand drawn, full size schematics.
https://www.dropbox.com/sh/zb7852nkp...vnm-kU4Qa?dl=0
Any info would be appreciated.
Thanks,
Joe Y