Robert Kirkland wrote:
> Collins used a separate bridge rectified screen supply, with a
> resonated choke input filter and a shunt load resistor. Good enough
> for Collins, good enough for me.?
- but only if you accept the whole "Collins package", which is a
separate (screen-cathode) supply and a separate (screen-anode) supply,
connected in series to provide the full anode-cathode voltage with a tap
for the screen. Each must be capable of delivering the full
anode/cathode current. Also, *none* of the anode, screen grid and
control grid voltages must be stabilized, so that they can all vary
together with the mains voltage.
Unless you do *all* of those things, you're not doing it the Collins
way. (Reference: "Single Sideband" by Pappenfus, Bruene and Schoenike...
of Collins.)
Finally, that power supply concept is now 35-40 years old, and
technology has moved on. Art Collins was always an innovator, and you
can bet he would have moved on too.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|