The 30 ohm input Z may be suspect.
One more thing, (probably not related to your circuit problem) I
noted that you are using 0.01 mica capacitors across the filament and
as blocker. Have you verified that the caps you used (with the lead
lengths) are not self-resonant at or below your operating frequency.
This could screw up your circuit performance. Maybe measure one with
a dip meter, impedance meter or the like? If thise micas don't bypass
the 2 filament leads well, you might consider ceramic chip
capacitors, the ones with flat leads for stripline mounting. Or
change the value of the micas until they really look like a good RF
short at your freq.
73
John
K5PRO
>An attempt was made to hook-up single 10 meter a pi-network input to
>a GS-35B. Unfortunately, it didn't work although seemed to check out
>okay on the bench and when it was installed in the amp on the bench.
>The pi-network C2, less 20 pF to compensate for the tube's input
>capacitance, was connected to one of the GS-35B's filament
>connections. L was attached to the same point on the filament and C1
>and the 0.01 uF mica blocking capacitor to the other end of L. A
>similar 0.01 mica capacitor is connected between the filament
>terminals. A 30 Ohm resistor was connected across C2 and the MFJ259
>connected to the free end of the 0.01 uF blocking capacitor. The
>circuit checked out okay. The filament choke was connected to the
>filament connections when the measurement was taken. The 30 Ohm
>resistor and MFJ259 were removed and the RG58 cable from the input
>relay was connected to the 0.01 blocking capacitor.
> 73,
> Mike, K4GMH
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