Technical Articles

Unpublished Articles


Boat Anchors


Boat Anchors Page

One of my hobbies is restoring old radio receivers - preferably ones with lots and lots of vacuum tubes. I particularly like the Hammarlund Super-Pro SP-600 in all its various versions. It is maybe not the best of the receivers of that era, but it has so much personality that I find it irresistable. When I was a kid, I had heard about the famed Super-Pro receiver, but I didn't know anyone who actually had one. In the mid-50's, they cost about $1200, which was well out of the range of the average radio enthusiast. Today, they are often sold by the pound. Even with my fading eyes, I can see all the parts in these receivers. You can actually fix them!

I also have done Technical Materials Corporation CV-591A/URR single sideband adaptors. Pictures and description Here and Here. This will take the IF ouput of the SP-600 directly and produce beautiful, clear reception for SSB. It is so clear that it sounds better than a lot of AM. It is totally over-engineered. Why use 3 tubes when you can use 10? The "restoration" process didn't really take much - just rebuilding the power supply and replacing a few tubes was all it needed.

NOTE: I do NOT do contract restorations. That is too much like work. If you have a receiver you want restored, please contact people that do contract work. Chuck Rippel often will do the SP-600 for people, although he tends to concentrate on the R-390A. His work is absolutely top-notch.

I have set up some pages devoted to particular receivers or particular affectations.

Hammarlund Super-Pro SP-600 Page

R-390 Page

R-1051 Page

BC-348 Page

R-5007 Page

Rohde&Schwarz EK-07 Page

SCR-578 "Gibson Girl" Radio Rescue Page

TMC Collection of Silent Key Charles C. Josey, K4LNL

Random Notes . . .

The Noise and Receiver Sensitivity Page

Just some notes on thermal noise and receiver sensitivity by me with a great note from Dallas Lankford.

The Antique Test Equipment Page

The Boatanchor era produced some wonderful test equipment. How did I ever get along without a Grid Dip Oscillator, or a Q-Meter?

This ad is talking about the invention of the 1-volt filament vacuum tubes. The thing the fellow is holding is a vacuum-tube portable radio! It must have weighed 8 pounds! My kids also liked their shoes and socks.

Remember the term "Granny the Riviter"? Well, here she is! This is an illustration from "Training for Victory" - from 1943. Putatively a preinduction training course in fundamentals of radio, prepared by the War Department. It was written by two gents from Westinghouse Electric. Yes, she is holding a riviter. She doesn't look like anybody's granny to me.

The poor pooch! This is also from "Training for Victory". Check the earpieces taped onto the head right in front of the ears. Remember, the dog is carying a vacuum-tube radio receiver with A and B batteries!.