Schematic for a pair of 833a` linear amp

[murdog]

Looking for above and schematic for power supply as well 40 .80 , 160 meters .
Thanks Mur

 

[Captain Kilowatt]

Anything that will supply 2500 volts would be good for a power supply. Not many amp schematics out there for an HF amp using 833A's or their heavier version the 833C. They are not a great choice for HF but since you only want 160/80/40m you should be OK. They take a lot of drive for full output however. I used to have some AM broadcast transmitters that used a pair in the RF section and another pair in the audio section. Google Gates BC1 series (BC1J, BC1H, BC1G etc) and you will get something you can likely modify to suit or you can start here.

https://www.google.ca/url?sa=t&rct=...QrmIE8cZoSUr1w&bvm=bv.136811127,d.amc&cad=rja

 

[BBB]

Antonio Vernucci in a Google group says: (below) "you'll find the diagrams of an AM transmitter using two 833s in parallel (class C), modulated by a push-pull pair of 833s. Reducing the grid bias down to about -70V, you may operate the 833s in class B for linear operation, still grid-driven.

It may however not be easy to maintain the neutralization bridge nulled on the
whole 3 - 30 MHz frequency range, and you may have to switch different
capacitors in the bridge on the various bands.

Alternately, you may try a grounded-grid filament-driven configuration. You
should then keep the filament at about +70V with respect to ground (using a 100W
NPN power transistor with a 70V zener between collector and base). I however
fear it may be hard to drive."

In reference to this created by Keith, WA1HZK >>>

http://www.criticalradio.com/833 Rig Project/Web Pages/Text Article.htm

Links to this >>>

http://www.criticalradio.com/833 Rig Project/Web Pages/Schematic Diagrams Page.htm

Iron for your project can be found here.Good luck!

http://www.pwdahl.com/

 

[Captain Kilowatt]

I had remembered that DX100 with the 833 amp but forgot where I had seen it. criticalradio.com never even came to mind.