Perhaps the least known rig in the stable of radios controlled by ERGO is the McKay Dymek DR-333. More on that in a moment.

I was introduced to McKay Dymek through its novel DR-33 receiver, shown immediately above. Two things made it novel. First, it looked like a piece of home entertainment equipment. Second, rather than a big tuning knob or two, the DR-33 provided four tuning knobs, one for each digit in its frequency. I am guessing that each knob controlled a decade counter in a frequency synthesizer. Tuning was cumbersome.

Although the DR-33 was a multi-mode full-coverage receiver, it was especially popular among radio broadcast engineers. It had excellent audio and good signal handling. Because of this, the DR-33 was frequently used as the main “off air monitor” in radio stations, including CJOB in Winnipeg where I worked. That’s where I first got to play with one. You can see the full specs and description in this 1980 catalog.

The McKay Dymek DR-333 arrived ten years later. It was one of the first PC controlled radios. Priced at $1500 it was not cheap. Special features included a built-in spectrum analyzer. Because of its cost, features and early computer control, I suspect it was mainly used as a surveillance receiver or scientific instrument.

McKay Dymek DR-333 Radio Control

I was introduced to the DR-333 by Nick Hall-Patch VE7DXR, a Canadian ham and radio listener based in Victoria. During one of my work visits to the west coast, Nick loaned me this radio so I could write an ERGO driver. Nick spent a lot of time using a sophisticated receiving system based on the DR-333 for measuring trans-pacific medium wave propagation.

This radio was quite complex to control. Software was required to send byte-level commands and data. This was especially for various tuning factors needed by the synthesizer and for tuning the IF chain. When you changed modes, you had to reconfigure the whole chain. Many calculations were needed.  I can’t remember if I ever had the manual, just some source code written by someone else that I was able to reverse engineer. It took a lot of trial and error, but eventually worked just fine.