The unit is highly portable at 850g and can be powered by four A-343 battery elements or via an external 9V power supply. Circuitry & Schematic (Shema)
The output power is rated at 500 mW nominal (800 mW maximum), driving a frequency range of 200–3550 Hz . This makes it suitable for speech and news broadcasts rather than music. alpinist 321 shema
The Alpinist 321 was designed as a "3rd class" portable receiver, prioritizing reliable reception in the Long Wave (LW) and Medium Wave (MW) bands over high-fidelity audio. The unit is highly portable at 850g and
It features a dual-band design covering LW (148.5–283.5 kHz) and MW (526.5–1606.5 kHz) . Using its internal magnetic antenna, it achieves a sensitivity of 1.5 mV/m on LW and 0.7 mV/m on MW, with a selectivity of 30 dB. The Alpinist 321 was designed as a "3rd
Detailed alignment frequencies for the heterodyne and antenna circuits include 1630 kHz (MW) and 145 kHz (LW), with IF (Intermediate Frequency) set to 165 kHz .
The board includes several trimmers for fine-tuning, such as R18 for detector mode, R22 for symmetry, and R26 for quiescent current adjustment.
The Alpinist 321 is a robust, lightweight vintage receiver. While its lack of FM (VHF) limits modern utility, it remains a favorite for collectors and hobbyists due to its straightforward schematic and repairable through-hole components.