[AMRadio] Has anyone built a linear using a 6c21 or 750TH?

Larry Szendrei ne1s at neandertech.com
Sat Jun 21 14:07:44 EDT 2008

AirRadio wrote:
> Has anyone built a linear using a 6C21 or 750TH, I found one of these, 
> sadly heater o/c in a hamfest recently and thought it might make a 
> great project if I could find a bit more about it and a working 
> example, so if you have a 6C21 or a 750TH in your junk box then I 
> would be interested in making it into a project amp. It would go well 
> with my BC-610, ART-13 and other boatanchor radios.  73 Max M0GHQ

Just last weekend I acquired a beautifully-constructed grounded-grid 
amplifier from the estate of John Rollins, W1FPZ, using (2), count them, 
two, 6C21s. I did not, however, get the plate supply with it - that went 
to someone else, as I have no room for it. It's a single-band amp for 
15M, but would easily convert to other bands. It's constructed 
breadboard-style on a wooden base covered with an aluminum groundplane. 
John was a real craftsman and engineer, and even homebrewed the 
hypersil-core filament iron.

Someday I'll fire it up, but right now it's sitting on the top of a 6' 
rack just sitting pretty and providing mood lighting for the shack!


More information about the AMRadio mailing list

This page last updated 20 Feb 2018.