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This project was designed to convert the IF frequency of a modern radio to the IF frequency of the Heathkit Scanalyzer.
The original SB-620 came with a number of different IF coils, you built the unit with the proper coil for the radio used at the time.  30 years later, most of the old additional coils are long lost, and now, converting the SB-620 to a new IF is no longer practical.

This project was built to convert the IF of  the ICOM 706MKIIG at 9.0115 MHz to the present IF of my SB-620 at 3.180 MHz

Building blocks are:
- 5.8 or 12.2 MHz  local oscillator
- input from ICOM at 9.0115 MHz
- double balanced diode mixer
- bandpass filter at 3.180 MHz
- (also  a small rf amp to boost the
  ICOM IF signal to usable levels,
  this  section is not shown here).




The project was layed out with EAGLE CAD software, The PCB was photo etched and drilled.
Silkscreened using a laserprinter, acetate sheet and an iron.