Hello,
Having an issue with a homemade GS35B operationon 15 and 17 m. When
keyed, the power seems to hesitate before going up to 1.5 KW
output. CW is a mess on these bands due to this situation. On RTTY
the power hesitation is so short that it doesn't present a
problem. Amp. seems to be okay to about 1200 W, but the hesitation
returns above this level. Other bands, 10, 20, 40, 80, 160 work okay.
Using a TIP147 transistor in a bias circuit similar to Ian's Triode
Board bias circuit. Cut-off bias is provided by a 10 KOhm resistor.
The filament choke is ~25 bifilar turns of #16 on a 10"X1"X1/4"
oblong ferrite rod. An additional choke of 20 turns #20 on a ferrite
rod, 3.5" long and 3/8" dia., is in the line from the filament
secondary center tap to the bias circuit.
This a strange situation as seen on 17 and 15 meters using either an
antenna or a dummy load. On the other bands, the power smoothly
rises to full output.
Any ideas on how to fix this situation are appreciated.
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