SP-210 Technical Data

All of the models are 18-tube (16 in the receiver, 2 in the separate power supply), single conversion superheterodyne receivers with 2 RF stages and 3 IF stages operating at 465 (*not* 455) 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 bands except the 0.1 to 0.4 MHz band, variable BFOs, diode noise limiters, 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. (That's 50 KHz at 10 MHz!) Total power consumption is about 180 watts.

The tube/stage lineup is:

  • V1 6K7 (VT-86) 1st RF Amp

  • V2 6K7 (VT-86) 2nd RF Amp

  • V3 6L7 (VT-87) 1st mixer

  • V4 6J7 (VT-91) HF Oscillator

  • Crystal Filter

  • V5 6K7 (VT-86) 1st IF Amp

  • V6 6SK7 (VT-117) 2nd IF Amp

  • V7 6SK7 (VT-117) 3rd IF Amp

  • V8 6H6 (VT-90) Detector

  • V9 6N7 (VT-96) Noise Limiter

  • V10 6SJ7 (VT-116) BFO

  • V11 6SK7 (VT-117) AVC Amp

  • V12 6H6 (VT-90) AVC Detector

  • V13 6C5 (VT-65) 1st AF Amp

  • V14 6F6 (VT-66) 2nd AF Amp

  • V15/V16 6F6 (VT-66) 3rd AF Amp (push-pull)

  • 5Z3 (VT-145) HV Rectifier (sep pwr supply)

  • 80 (VT-80) Bias Rectifier (sep pwr supply)

NEW! Redrawn BC-779B schematic by Eberhard Hewicker, DK3HE. Provided in two PDF files, which can be printed and taped together. Can also be greatly zoomed/magnified for those tired old eyes. Part 1 and Part 2.

The Vintage and Military Amateur Radio Society Super Pro manual scans and photos.

Schematic -- External Power Supply RA-74C Tube Socket Voltage and Resistance Tables.

RF/OSC alignment diagram RF Sensitivity and Audio Response graphs IF Selectivity graph

How to run your SuperPro on batteries. The batteries, however, should be on steroids! The approximate power requirements (based on the power supply variants) are 380 VDC at 50ma, 250 VDC at 100ma, 100 VDC at 4.5ma, -50 VDC at 11ma, and 6.3 V (AC or DC) at 7 amps.