on 4/5/01 1:02 AM, Jan.E.Holm@telia.se at Jan.E.Holm@telia.se wrote:
>
>
> Strange, I dont see that. The gain is "pritty much" the same
> 160 - 15 m with my 4-1000A´s, dont run them on 10.
>
The reason I see the varying gains across the bands on my amp is probably
two-fold: Input networks and output network.
My input pi-nets are not in an ideal location and are not as close to the
tube as I would like them to be. I really had no choice as when I built my
RF deck I was using someone else's mechanical layout (something I would not
recommend). On the low bands, the layout is less critical than on the
higher bands.
The other big problem would probably be the tank circuit as I stated earlier
that the stock B&W 850A does not have the best inductance values. It
certainly is usable, but there are better tank coil solutions out there than
the 850A.
That's probably why I see some gain variation and it's probably not tube
related.
73,
Jon
NA9D
-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)
Member: ARRL, AMSAT, DXCC, NRA
http://www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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