National NC HRO “Sixty” Receiver w/Plugin Coil Set

HRO-60 receiver

The HRO-60 is one of the most iconic shortwave receivers in radio history. Although it was first made back in 1952 it is still sought after by modern radio collectors and listeners.
The HRO-60 was manufactured by National Radio Company of Malden, Massachusetts (moving to Melrose, MA in 1964). The last HRO-60’s were produced in 1962.

HR-60 plugin coils
HR-60 plugin coils (click on any image to enlarge)

This is a massive receiver that weighs in at 85 pounds. National, like many of its contemporaries, was of the mindset that big is better. They were looking to produce radios that had an integral power supply, lots of room for wiring and airflow, and a very stable received signal.  A stable receiver is one that can be tuned to a frequency and remain on that frequency for hours without drifting off to another frequency, a common fault caused by the buildup of heat. The HRO-60 achieved this goal easily. Every band that it covered (9 basic bands and 4 expanded bands) was accessible by using a plug-in coil rack. If you were listening to say the 10 meter band (plug-in AA, 27.5-30 MHz) and wanted to listen to 40 meter amateur radio operators you just removed the AA plug-in (first turning off the B+ high voltage) and replaced it with the B coil (7-14.4 MHz). The  radio, as supplied, receives AM and CW signals. There was a module available for narrow FM. Although it is not designed to receive single sideband (SSB) which is used by modern amateur radio operators it is possible to receive by use of the BFO dial on the radio.

There were many options available such as the XCU-60-2 crystal calibrator that allowed the operator to precisely calibrate the receiver dial scale in 100 or 1,000 kHz (kilohertz) segments. All of the coil plug-ins except for A, B, C, and D were optional as was the model 60TS speaker. When first released in 1952 the radio cost $483, quite a lot for a communications receiver when you consider that the average price for a new 1952 car was $1,700.

References

Universal Radio, shortwave receiver page: HRO-60 page
https://www.universal-radio.com/catalog/commrxvr/HRO60.html

Boatanchor Pix website, photos and cartoon
https://people.ohio.edu/postr/bapix/HRO60.html

Restoration and care of the HRO-60 is covered in depth by Emmitt’s Fix It Shop.
http://emmittsfixitshop.com/Projects_HRO.html

HRO-60 blog posting by our museum volunteer Ken Carr, Reviving the HRO-60
http://idlenot.com/?p=624

Shortwave Receivers Past & Present, by Fred Osterman, 2nd edition, 1997

Radio Boulevard of Western Historic Radio Museum, History of the HRO Communications Receivers
https://radioblvd.com/National%20HRO.htm