[BULK] - [Amps] 2m Linear Amp Enquiry

[Steve Thompson]

On Thursday 09 September 2004 21:34, Steve Katz wrote:
> > Has anybody got experience of the Amp listed in the Tech web pages of
> > 6m.com?  It was for 2m using 2-4cx250b (shown as Horizons 12-62) zip file
> > c5
> > It looks easy to build, and has a PI output network.
> >
> > //The 6mt.com website is so painfully slow to load I don't have the time
> > to look for this; however a pi-network for high power on two meters seems
> > like folly.  Every dual 4CX250 amp I've ever built for 2m (several of
> > them) always used the tubes in push-pull with tuned plate lines, tuned by
> > a tiny bit of variable C between the tubes, and link coupling.
Search around for the W2GN design using a pair in parallel, it works a treat. 
I modified the grid circuit to have separate bias control, so it will work 
with unmatched tubes. Personally, I don't like link coupling - it's possible 
to get false indications of optimum loading.

Steve