Sonar PixBoost
The Sonar Radio Company of Brooklyn NY announced their first (and, as far as I know, only) TV booster in the middle of 1948. The channel 1 markings indicate the time just before the FCC reassigned the 48-54 MHz frequency to Ham and Land Mobile service. The simple wooden box with silk-screened front panel and off-the-shelf knobs represent pretty much the state of the art styling at the beginning of the post-war television boom.
Like most early TV boosters, this is a simple device, with separate circuits for High and Low channel ranges. Each range has its own tuning capacitor and 6AK5 amplifier tube, with a switch to select between High and Low band. A 6C4 was used as a rectifier tube. Sonar claimed that the PixBoost could also be used as a Ham Radio preamplifier for the 6 and 2 meter bands (50-54 MHz, and 144-148 MHz), reflecting the wide tuning range. No claims of gain or noise figure were made.
I had been searching for this model for several years without ever seeing one beyond the photo in a 1948 magazine. This one -- in excellent original condition -- appeared at a local antique radio swapmeet in a pile of nondescript radio parts, and I could hardly get my wallet out fast enough!
Updated December 3, 2003