Hammarlund Super Pro

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1939 ad for the SP-200 Super Pro
1939 ad for the SP-200 Super Pro

The Hammarlund Super Pro SP-200 series is an American made radio communications receiver also known as the military BC-779 which saw wide use in World War II.

Contents

[edit] History

In 1935, the Hammarlund Manufacturing Company introduced the first of the famous “Super-Pro” line after more than four years of planning and engineering: the SP-200 series, an 18-tube, single conversion superhet receiver. While designed as a communications receiver, Hammarlund promoted a home version in a console cabinet during the mid-thirties.[1] The Super-Pro receivers were manufactured through 1945, with many thousand delivered to the military during World War II. The SP-200 series (Military designation BC-1004, BC-794, BC-779-B) saw wide use by the U.S. Signal Corps. According to a November 1940 QST ad, "The fact that 'Super-Pro' receivers are used extensively by the U.S. Signal Corps and many other governmental departments, speaks for itself." The three basic models (there were additional variants and modifications) were:

  • SP-210-X or BC-1004-C (0.54 - 20 MHz)
  • SP-210-SX or BC-794-B (1.25 - 40 MHz)
  • SP-210-LX or BC-779-B (0.1-0.4 and 2.5-20 MHz)[2]

At the end of the war, the market was flooded with surplus Super-Pro receivers at bargain prices, which may be a reason many working examples of this model are still found today.

Hammarlund produced the SP-400X Super Pro for the amateur radio market from 1946 to 1948. [3] In 1947 the SP-200 was superseded by the SP-600 Super-Pro receiver.[4]

[edit] Specifications

Various models cover 0.1 - 40 MHz in 5 bands. The radio and cabinet weigh 73 pounds (33 kg) while the separate power supply adds another 57 to 61 pounds. The Super-Pro was first offered in two basic models, one with, and one without, a crystal filter. [5] All the models are 18-tube (16 in the receiver, 2 in the separate power supply), single conversion superhets with 2 RF stages and 3 IF stages operating at 465 kHz. In addition to a 5 position single-crystal filter with variable phasing, the IF selectivity is continuously variable between 3 and 16 kHz. The radios are equipped with full bandspread on all except the 0.1 to 0.4 MHz bands, variable BFO, diode noise limiter, and 14 watts of audio output power. Claimed sensitivity is 1.0 to 1.7 microvolts on the LF and HF ranges. The main dial calibration is 1/2 of 1 percent of the highest frequency on each band. Total power consumption is about 180 watts.[6]Initially, two versions were manufactured. One tuned from the low end of the broadcast band to 20 MHz, and the other started at 1250 kHz and went up to 40 MHz.[7]

[edit] References

  1. ^ http://www.antiqueradios.org/gazette/superpro.htm AntiqueRadios.org
  2. ^ http://www.roveroresearch.com/sp200/bc779_1.html Rovero Research - The BC-779
  3. ^ http://www.dxing.com/rx/sp400x.htm DXing.com, Favorite Tube-Type Shortwave Receivers, Hammarlund SP-400-X
  4. ^ http://www.hammarlund.info/histpage.html The Hammarlund Historian
  5. ^ Rovero Research Super-Pro 210-LX Page
  6. ^ Rovero's Hammarlund Series 200 Technical Data
  7. ^ HAMMARLUND Service Page

[edit] General references

  • War Department Technical Manual TM11-866, 31 August 1943 Radio Receivers BC-779-B, BC-794-B, and BC-1004-C and Power Supply Units RA-74-C, RA-84-B, and RA-94-A
  • Instruction Book for "Super-Pro" Radio Receiver (100-400 kc and 2.5-20 Mc), overprinted Radio Receiver BC-779-A and Power Supply Unit RA-84-A, Undated, Published by Authority of The Chief Signal Officer, Order No. 21109
  • Series 200 Super-Pro by Hammarlund, undated.
  • Communications Receivers, The Vacuum Tube Era 1932-1981, 3rd Edition, by Raymond S. Moore

[edit] See also