I'm looking at the spec sheet for the 3-500Z at
At the top of the second pages, it gives numbers for various parameters at
different levels of high voltage (3000, 2500, 2000, and 1500). Are these
voltages at load or no-load? And how do Single-Tone DC Plate Current and Peak
Envelope Useful Output Power correlate with key down plate current and output?
The reason I ask is because I picked up a homebrew 6m amp with a single 3-500Z,
which uses a power transformer from an SB-200. Key down power output is 400w.
Assuming the amp's meters are accurate, no-load plate voltage is 2300v, and
plate voltage under full load is 1950v. Plate current with no drive is 100ma
and plate current with full drive is .52a. About 40 watts of drive produces
the full 400w out. Further increases in drive, up to 100w, do not increase
Judging from the spec sheet's 2000v table, my guess is that the amp is
performing as well as it can with this power supply. I know that a converted
AL-80B with a single 3-500Z can produce 900w or so on 6m, but it has a 3000v
Do you think it would be OK to run this amp at the full 400w in WSJT
(continuous carrier) modes?
73, Bill NZ5N
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