[AMPS] ? about tuned input, sorry....

Steve Harrison ko0u@os.com
Sat, 19 Feb 2000 19:57:03 +0000


At 02:07 PM 2000-02-19 -0500, NS1Z / John wrote:
>
>I have a Grief Kit SB-221 that has been gutted and put on 6 meters. The
>input VSWR is >2.5 and I would like to tame it for my FT-847 driver. Seems
>to me I remember something about soldering a resistor across the cathode to
>simulate the active input impedance??

An input circuit for any single band shouldn't be the least bit difficult
to match to the tubes. I'd sure look into the existing input circuit as
it's not at all right with that kind of high VSWR. Putting a resistor on
the cathode side, even if you find a value that helps, will just be a
bandaid. For all you know, the cathode side may already be too LOW
impedance. You really need to get into that input tank and find out why
it's not doing its job.

73, Steve K0XP

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