>
>My SB-220 currently does not develop "full" grid current (for the sake of
>argument, 200 ma.) on any band but 40m, when driven with a TS-930.
? There is no specified grid current. Grid current varies depending on
anode supply V. Tune for max, peak output with max, peak drive. When
too many electrons are diverted to the grid, fewer electrons pass to the
output - so the output drops. note - on the SSB tap, since the anode
supply V. drops considerably under key-down (AØ/NØN) - which changes RL -
it is best to adjust for max. RF out using a tuning pulser or a cw
keyer sending 50wpm dits.
>presume this is due to the well-documented shortcomings of the stock input
>circuits.
? The saving grace is that the 220's tank inductors - as well as the
bandswitch - are forced air cooled.
>My question is, if I were to use a 200-watt transceiver, could I
>expect to turn up the CW power till the grid current reached the 200 ma.
>level, and realize additional output power, or would the relatively low
>plate voltage cause the output to flatten out before that point?
>
? Output is limited by peak cathode emission - c. 1.3a-peak. At 2900V.,
130w drive is about the limit for linear operation with a SB-220.
>And yes, I know the additional power would be virtually unnoticeable on the
>other end.
? good point, Pete. cheers.
>...
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|