The schematic calls the input Cap for 20 350pF, I supposeits value could
have changed over the years, assuming it was correct to begin with.
Thanks.
Rick.
----- Original Message -----
From: "rlm" <2@vc.net>
To: "Davis_R" <WD8JJA@arrl.net>; " AMPS" <amps@contesting.com>
Sent: Monday, March 10, 2003 10:37 AM
Subject: Re: [Amps] Tuned Input
>
>
> >Hmmm, 'minimum is under 1.2 to 1' ? that makes me wonder --
> >
> >1.2 to 1 seems pretty tight, what would the VSWR bandwidth be?
> >
> ** beats me but some solid-state transceivers begin to throttle back c.
> 1.2:1.
>
> >Makes me ask a question -- I have an FL-2100B, I bought it used and it
seems
> >to work FB, but I checked the input coil alignment and found one band (20
m
> >if memory serves me correctly) that I could not bring down low enough to
> >really make me happy. I think it was 2 - 3 to 1 at best. (I don't think
any
> >were as low as 1.2 to 1). What do I look at to improve this?
>
> ** Increase the Q of the tuned input by increasing C-in, C-out, and
> decreasing L. For 20m, a C-in of c. 390pF should do ok.
>
> > Is it likely
> >to be the adjustable inductor? Or would it be easier to replace one or
both
> >or the tuned input capacitors?
>
> ** C-out and L need to be adjustable. When you arrive at something that
> works, replace the adjustable C with a fixed unit.
> >
> cheers, Rick
>
>
> >----- Original Message -----
> >From: "rlm" <2@vc.net>
> >To: "Ed" <edw3nr@nexband.com>; " AMPS" <amps@contesting.com>
> >Sent: Sunday, March 09, 2003 7:00 PM
> >Subject: Re: [Amps] Tuned Input
> >
> >
> >>
> >>
> >> >I want to make sure I am right here. Tune the input for best SWR
> >>
> >> ** Yes, provided the minimum is under 1.2 to 1. If it's not, the Q of
> >> the tuned input needs to be pumped up,
> >>
> >> >and maximum
> >> >Grid current or ????????? ...........73
> >> >
> >> ** Tune for max RF out with whatever drive level produces the rated
max
> >> anode current. Max out always results in a reasonable amount of
> >> grid-current because if too many electrons are diverted to the grid,
> >> fewer electrons arrive at the anode and output drops.
> >>
> >> cheers, Ed
> >>
> >> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> >> www.vcnet.com/measures.
> >> end
> >>
> >> _______________________________________________
> >> Amps mailing list
> >> Amps@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/amps
> >>
> >_______________________________________________
> >Amps mailing list
> >Amps@contesting.com
> >http://lists.contesting.com/mailman/listinfo/amps
> >
>
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
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