The Hickok 277X is a Universal Crystal Controlled Signal Generator manufactured by Hickok Electrical Instrument Co. in Cleveland, OH, with production estimated around 1946. It was a high-end tool for radio repair and alignment, designed for both AM and FM receiver servicing.
Key Features
- Frequency Range: 7 bands from 100 kHz to 110 MHz, covering AM, FM, and VHF bands.
- Modulation Capabilities: Supports AM, FM, and external modulation, as well as frequency sweeping and audio frequency outputs (fixed 400 Hz, variable, and swept).
- Crystal Control: Includes a built-in crystal calibrator for precise frequency reference (100 kHz and 1 MHz).
- Design: Uses 6 tubes (6C4, 6SN7, 6SG7, 6X5, 6SJ7), runs on 110V AC, and features a metal case.
- Physical Specs: Measures 13 x 16 x 7 inches (330 x 406 x 178 mm) and weighs 33 lbs (14.98 kg).
Differences from the 288X
The 277X is identical to the 288X, except it lacks the decibel (dB) meter used for monitoring receiver output levels.
Otherwise, both models share the same circuitry, frequency bands, and modulation features.
Restoration & Use
Restoration typically involves replacing electrolytic and paper capacitors, cleaning contacts, and repairing mechanical parts like the dial window. The Boatanchor Manual Archive (BAMA) and Glendale Manuals offer reprints of the original 288X manual, which covers both the 288X and 277X models, including schematics, operation charts, and calibration info. It is considered a desirable vintage tool for antique radio enthusiasts and restoration hobbyists, though its complexity requires familiarity with its operation.