I just finished a 4-1000A for 6M, with a 3-30pf vac cap and 7.6 pf of tube
capacitance, already too much for a 5000 ohm plate impedance.
I've built a 6m 4X1 with 30pf vac cap before and it ran 1500 out no problem
using a pi-net and 4500 volts. The best this one has done is 400 out, with
3KW input! The tuning cap was at min, the coil at that time measured .42
uh, the 17-115 loading cap was at 115.
I've gone up & down with value of the coil, both get worse! Most
combinations are 50 watts out with 100W drive. Any ideas what might work?
I've got a desk full of 1/4" copper coils...
de Dick NY1E
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