Rockwell/Collins
 HF-2050 Receiver

The Rockwell/Collins HF-2050 is a double-conversion superheterodyne solid-state receiver made between 1984-91. Manufactured in Canada for military customers, the HF-2050 is the first production receiver to use digital signal processing.

It's not easy to service a receiver as complicated as the HF-2050. The technical manual itself is larger than many modern communications receivers!

On the left of this top-chassis view is the large logic board, connected by a ribbon cable to the front panel. The aluminum module on the right contains the +12V, -12V, and +5V power supplies.

Design Features: The 38 lb HF-2050 is an all-mode rack-mount frequency-synthesized communications receiver that tunes 14 kHz to 30 MHz. The radio shown here has thirty memories, but later production receivers had 100 memories.

 
The receiver has IF selectivity settings of 0.3 kHz, 1 kHz, 2.8 kHz, 3.2 kHz, and 6.0 kHz, and three user-selected tuning rates. The radio also features a dual-speed AGC, adjustable noise blanker, squelch, variable BFO, and small front-firing speaker.

The HF-2050 is controlled by a microprocessor, which features a Built-In-Self-Test (BITE) mode. Any malfunction generates a front panel error code.

 
The biggest design flaw of the HF-2050 is the power supply. Using inefficient series regulation, the supply generates a large amount of heat -- so much, in fact, that the receiver will shut down if operated on its side for a few minutes. Many users supply their own muffin fans to cool the radio. The other major design flaw is the lack of backlighting on the LCD display.

This underside view shows the RF circuitry of the HF-2050. Critical RF circuits are in modules, interconnected with small teflon-coax with gold connectors.

Operating Impressions: The HF-2050 is an outstanding performer, but to me is not a pleasure to operate. The "slow" tuning rate is evidentally intended for data communications and is far too slow for SSB or even casual CW reception. The medium tuning rate is fine for AM, but too fast for SSB. The microprocessor is prone to shutting down the receiver for minor malfunctions. Although these "faults" have always been corrected by turning the radio off and on again, they leave me in a state of anxiety about the radio's reliability.