On Wed, Apr 16, 2025 at 07:32 AM, Fran?ois wrote:
Just to add some elements to the discussion. Here's what I noticed on my Drake L-7, so with 2 x 3-500Z. The -9V bias on the grid is generated directly on the grid; the 9V zener is not in the cathode circuit.
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Note that the grid current is lower when the plate voltage increases.
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In France, we're limited to 500W, but I wonder how in the USA you can reach 1 kW without exceeding the maximum Eimac values.
That 1 kw pep output from the single 3-500Z? is because they are using IVS? (intermittent voice ratings) for SSB.? ?That operation was approved by Eimac.
IE:? it's because of the low duty cycle on SSB.?
They rate the same amp at 850 watts? output on CW mode.? Same idea,? CW is a reduced duty cycle....... but not as much as SSB...... hence the 1000/850 ratings? for SSB / CW.?
