Zenith Cobra record player

Thanks, Tony. I'll pass that information on to the owner.

WC

I've got a 1948 Wurlitzer jukebox, a Model 1100, that uses the Zenith Cobra arm and the cartridge that modulates an RF signal. Mine was a factory conversion to 45 rpm records. I suspect that the design was a way of producing a higher-quality signal than you could get with the crystal cartridges that were common in the 1940s. You could get higher compliance (less record and stylus wear), more durability, and better frequency response. The cartridge is really just a moving vane with the stylus attached to it. The Wurlitzer schematic calls the one tube modulator/demodulator a "preamplifier" but it really isn't a preamp as we knew them later.

Chris Campbell