Hi Rick,
That's about par for the course for this amp - remember , it's old enough
that transistor finals were not very common, or even non-existant. Take a
look at my homepage, there is a description of my (very extensive) rebuild
of my FL2000B, which happens to include a redesign of the input matching.
Vy 73 de OZ1PIF, Peter
********** OZ1PIF **************
email: oz1pif(no-spam-filler)@get2net.dk
http://hjem.get2net.dk/oz1pif
Ph. +45 4619 3239
Snailmail:
Peter Frenning
Ternevej 23
DK-4130 Viby Sj.
Denmark
***********************************
----- Original Message -----
From: "Davis_R" <WD8JJA@arrl.net>
To: " AMPS" <amps@contesting.com>
Sent: Monday, March 10, 2003 4:01 PM
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?
>
> 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? Is it likely
> to be the adjustable inductor? Or would it be easier to replace one or
both
> or the tuned input capacitors?
>
> Rick, WD8JJA
>
> ----- 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
> >
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