Note
Ham Radio, Apr 1972, p. 74.
QST, Aug 1972, p. 143.
QST, May 1973, p. 173.
QST, Feb 1974, p. 126.
QST, Jun 1975, p. 146.
QST, Jan 1976, p. 90.
QST, Jan 1977, p. 157.
As late as 1977, if you still had an old Gonset Communicator hanging about, Palomar enabled you to use it on FM. The FM modulator plugged into the crystal socket and mic jack of the Communicator, requiring no modi-fications to the Gonset. A built-in tone burst encoder was a $10.00 option.
Palomar Engineers' frequency modulator puts the Gonset Communicators on FM without any modification or rewiring. The microphone plugs into the frequency modulator. One of the cables coming out of the modulator plugs into the Communicator's microphone jack and carries the push-to-talk line, but no audio. A second cable has a crystal plug. It plugs into any one of the Communicator crystal sockets and the crystal plugs into it.
A variable capacitance diode in the crystal plug frequency modulates the crystal and the frequency multipliers in the Communicator increase the deviation to about ±8.5 kHz at the output frequency.
The frequency modulator works with the Communicator I, II, Ill, IV and GC-105. There are no tuned circuits in the modulator so operation is not restricted to the two-meter amateur band alone.
Built-in tone burst is available for use with repeaters. The half-second tone burst is keyed by the push-to-talk switch. A carrier frequency adjustment allows the frequency to be set exactly.
Other modulation, such as frequency shift keying, can be applied to the frequency modulator. An audio level of 10mV is required. The frequency response of the modulator is 200 to 3500 Hz. Clipping on voice is approximately 7 dB.