TheoryTron

TheoryTron is a discontinued series of TVs created and marketed by Theorysonic from 1964 to 1989 and it was replaced by the current Nehervia television sets. It is available in NTSC, PAL and SECAM markets.

History
Theorysonic had entered the television market in 1964 along with radio.

To watch UHF and cable TV channels, the viewer needs a UHF converter or set-top-box for TheoryTron to watch more channels like channel 23.