Phil wrote, in part:
> After converting and canabalizing numerous industrial amps that
> are VERY overengineered due to their continuous duty requirements,
> I came up with a rule of thumb for plate blocking cap values without
> having to do a lot of computations each time you "roll a new one."
> I have used 10 pf per meter. IOW, 100 pf for 10 meters and 1600 pf
> for 160 meters.
For what it's worth,
in the Henry 8KU, which is used in pretty continuous duty
in several "3rd" world SW BC stations, the plate block
is done with a 1000pf, 7.5kV, ceramic unit. Per the 8K
manual, the part is an HEC 50v102MA part number.
Same capacitor is used at the same spot in the 3K Ultra.
Don't know the current rating, maybe disguised somehow
in the part number.
73, Jim, KH7M
Both amps can be set up for anywhere from 1.8 up to
30 mHz.
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|