Updated 10-24-2002

OLD RADIO
November 2002 Column

 

 

The Black Box - The schematic is here, Finally!

10-16-02 - I hoped to have the schematic on line but computer problems seem to be following me. Last month it was the computer and the hard drive. This month, and today to be exact, my old-reliable PaperPort scanner has decided to stop working. I saw a newer model at Sams Club the other day for under $50., so I guess I'll drop by tomorrow and pick it up......

10-24-02 update - I now have the new scanner running. Bargains aren't always bargains. It needed new driver software to properly work with the USB port on my computer.

It took a while to figure everything out, but wow is it fast! Much faster than the old Parallel port before. My other projects should be completed much faster now.

If you have early QST magazines, this article is in the January 1949 on page 48. The basic circuit is still popular with collectors today, it's a 6L6 oscillator driving an 807.

The radio in the photos below was built from that QST article. My friend and fellow collector Pete Grave, an SWL from Pennsylvania, found this at a Hamfest and thought it would be a good subject for the Old Radio column.

 

Schematic for the Transmitter
From the January 1949 QST, page 48

 


The cabinet is made by Bud, and is 7 x 7½ x 12-inches wide. The cabinet also has a lid to make it convenient to change the plug-in coils for each band.

 


The basic circuit is still popular with collectors today, it's a 6L6 oscillator driving an 807. The 6L6 would also be a VFO so one could change frequency. The transmitter would be used on CW in the 80 and 40-meter bands.

 



John Dilks, K2TQN    125 Warf Road, Egg Harbor Township, NJ 08234-8501   e-mail: K2TQN@arrl.net