Note
QST, Apr 1964, p. 137.
QST, Jan 1965, p. 102.
Manufactured by Galaxy Electronics (Council Bluffs, Iowa), the Galaxy III is an HF transceiver designed for SSB and CW operation. It provides full coverage of the 80, 40, and 20 meter bands with linear VFO tuning, anti-backlash planetary drive mechanics, and over 9 inches of bandspread on a circular dial.
The Galaxy III utilizes a hybrid design consisting of 15 vacuum tubes (including two 0A2 voltage regulators) alongside solid-state transistors and diodes:
Features / Specifications
– Power Input: 300 watts PEP SSB and 300 watts CW.
– Full coverage on 80-40-20 meters. 500 KC all bands.
– Dual vernier tuning 12:1 fast tune, 72:1 slow tune.
– Final Output Stage: A pair of 6HF5 beam power pentodes running in parallel into an adjustable pi-network designed to match 40–100 ohm resistive loads.
– SSB upper & lower sideband. Shifted carrier CW. Panel indicator lamps, featuring carrier suppression in excess of 45 dB and sideband suppression exceeding 55 dB.
– New! 6-section crystal filter. 1.8 to 1 shape factor at 2.1 kHz bandwidth.
– Automatic Level Control (ALC): Uses 1N462 rectifiers to sense grid current and control IF gain to prevent flattopping and increase effective speech power.
– CW Mode: Utilizes shifted-carrier keying at 9.000 MHz with grid-block mixer keying.
– Drift less than 100 CPS in any 15-minute period.
– Sensitivity: Less than 0.5 uV for a 10 dB Signal-to-Noise ratio. – Filter: A 9.0 MHz crystal filter providing a 2.1 kHz bandwidth.
– AGC System: Two-speed Automatic Gain Control (fast attack/fast release for quick signal variations, slow attack/slow release for larger swings).
– Audio Output: 3 watts low-distortion audio output feeding an external 4–8 ohm speaker or high-impedance headphones.
Optional Accessories
– VOX: Supported via an optional plug-in printed circuit board utilizing a 2N1274 VOX amplifier, 2N697/2N1274 DC relay drivers, and anti-VOX circuitry.
– 100 kHz Crystal Calibrator: Plugs into an internal octal socket for dial calibration.
– Remote VFO & Mobile Mount: Supports an external remote VFO via a rear jumper socket, as well as a 12 VDC mobile power supply configuration.
Tube LIneup (15 total)
– 12BZ6
– 6HG8
– 12BA6 IF 9.0 MHz
– 12BA6 IF 9.0 MHz
– 6GX6 Detector / osc
– 6EA8
– 12AT7
– 12BA7 Transmitter mixer
– 6CL6 Driver
– 6HF5 Final amp
– 6HF5 Final amp
– 0A2 Voltage regulator
– 0A2 Voltage regulator
– 6EA8 Mixer / crystal osc
– 6EA8 VFO / cathode follower
– 12CU5: crystal calibrator (if present)
References
Review: QST, Oct 1964, p. 60.
