Note
The HX-11 was released in November 1961 and was sold for only about a year and a half. The HX-11 is essentially an updated version of the DX-20. While they are many similarities to the DX-20 (tube line-up, power output, front panel layout, crystal access hatch, and size cabinet, for example), there are some significant differences, the obvious of which are the paint style and meter.
A major difference between the DX-20 and the HX-11 is the addition of a low pass filter, located under the chassis, which limits antenna impedances to 50 to 75Ω. Also, the output loading capacitor is no longer at the rear of the chassis with an extension shaft, it is now mounted near the front panel.
All the interconnect wires are crammed between the capacitor’s frame and the front panel. That makes for very tight wiring along the front of the chassis and front panel. In addition, the capacitor’s frame is sitting on top of the rubber grommet with the wires from the front panel metering DPDT slide switch.
Other changes include the availability of switched power for an external antenna relay (provides 120 VAC to relay coil), and a fuse. And while Heath no longer advertised 11 meter operation, it is still possible.
CRYSTAL CONSIDERATIONS
Band Fundamental Crystals
80 m 160 or 80 m
40 m 80 or 40 m
20 m 80 or 40 m
15 m 40 m
10 m 40 m
Power input: 50 watts
Output impedance: 50 to 75Ω
Output coupling: pi network, coaxial
Frequency control: crystal or optional external VFO
Band coverage: 80, 40 , 20, 15, and 10 meters
Power requirements: 120 VAC, 50/60 Hz, 180 watts maximum
Size: 13 wide x 8.75 high x 7 deep; Weight: 16 lbs
Tubes: (1) 5U4, (1) 6CL6, (1) 6DQ6
References
Review. Popular Electronics, Mar 1962, p. 79.
Photos, general information and specifications from "Heathkit: A Guide to the Amateur Radio Products," by Chuck Penson, WA7ZZE. Used with permission.
