Homemade Equipment Pictures 2

The WR/5686-80 Regenerative Receiver

Photograph of WR/5686-80 regenerative receiver next to stacked 40- and 30-meter converters.
Figure 0—The WR/5686-80 regenerative receiver covers the Morse-code-friendly portions of the 80-, 40- and 30-meter amateur radio bands with the help of SA602/NE602-based 40- and 30-meter converters built in Wrigley's gum cans.
Oblique front-panel photograph of the WR/5686-80 regenerative receiver.
Figure 1—Front view of the WR/5686-80 regenerative receiver for 80 meters. The front-panel rotary controls are, from left to right, are FAST TUNING [FT], REGENERATION, and SLOW TUNING [ST]. The toggle switch selects L (LOW, approximately 3470–3538 kHz) and H (HIGH, approximately 3533–3601 kHz) tuning ranges. The ST control varies the tuning about ±2 kHz from the center frequency set by FT. The WR/5686-80 is a variation on the 40-meter Watch Receiver scaled to 80 meters; the detector is a 5686 beam power tube Hartley, and the circuit's grounded-grid RF buffer and AF voltage amplifier triodes comprise a 6C8G dual triode. The utility audio amplifier/filter box brings the WR/5686-80's audio output up to headphones or speaker level. The big cans shield the set's vacuum tubes.
View inside the WR/5686-80 receiver tuning head showing the trimmer and tuning capacitors, tuned-circuit inductor, range switch, and regeneration control.
Figure 2—View inside the WR/5686-80 receiver tuning head showing the trimmer and tuning capacitors, tuned-circuit inductor, RANGE switch, and REGENERATION control. The soldered-on box cover has been temporarily removed.

[to be continued...]


Revised July 19, 2015 CE. Copyright © 2015 by David Newkirk (DavidNewkirk@gmail.com). All rights reserved.
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