Hello Will,
Thanks for the suggestion on checking the bandswitch as each band has
a separate position. I'll do that and get back to you.
Each band has a separate pi input circuit matched to the tube under
operating conditions.
At 11:52 PM 7/2/2006, Will Matney wrote:
>Mike,
>
>Did you check the bandswitch contacts for these two frequencies? Do
>you have a seperate input match for each frequency that's switched?
>
>Best,
>
>Will
>
>*********** REPLY SEPARATOR ***********
>
>On 7/2/06 at 11:45 PM Mike wrote:
>
> >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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> >Amps@contesting.com
> >http://lists.contesting.com/mailman/listinfo/amps
73,
Mike, K4GMH
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