[AMRadio] Ferroresonant transformer revisited

W5OMR/Geoff w5omr at satx.rr.com
Wed May 10 13:04:37 EDT 2006

Rick Brashear wrote:

> No doubt, they are noisy rascals, hot too.  Geoff, I'm glad you 
> mentioned 450TL.  I have one I acquired with an old BC-610 someone had 
> hacked up trying to make an amplifier.  Is there a way to test more 
> than the filament other than putting it in a working amplifier?  I'd 
> kind of like to build something around it, but would hate to get it 
> all complete only to find the tube was too weak or dead.
> Rick/K5IZ 

Other than testing the filaments, no - I don't know of a way other than 
comparing it in an amp designed to use 'em.

Speaking of which, Rick... I've got an amp that someone started to 
home-brew, designed around a 450T.  Filament is 220v primary, at 7.5v

big peice of copper tubing for a coil, tapped for 80, 40, 20 and 10m.

And, I have a brighly glowing 450TL to go along with it.

If you're interested, I'll send some pictures of it.

73 = Best Regards,

More information about the AMRadio mailing list

This page last updated 24 Jan 2018.