Another question, Peter,
What do you mean by "carefully" checking the caps?
Rick, WD8JJA.
----- Original Message -----
From: "R_Davis" <WD8JJA@arrl.net>
To: "H & W Electronics" <info@handwelectronics.com>;
<Fox_Tango@mailman.qth.net>; <amps@contesting.com>
Sent: Monday, October 27, 2003 8:51 PM
Subject: Re: [Amps] FL-2100F/B
> Very interesting, Peter,
>
> Actually, the question was proposed by "H & W Electronics" on another
> reflector; I have a 2100B with the similar symptoms, while he asked about
> the 2100F.
>
> The 2100B schematic calls for a 220pF on each grid. If only one went bad,
> wouldn't I see a different response by using only one tube and switching
it
> from one socket to the other?
> What do you think about the disc/electrolytic combination between the
> bias-set resistor and the RF choke? This may be just a filter for the
ripple
> on the half-wave rectified bias, but they are common to both tubes. so if
> one was leaking, wouldn't it pull both grids down by the same amount? I
> can't read my schematic very well, but it looks like they are a 0.01 uF
disc
> to ground in parallel with a 2 uF/25V electrolytic to ground (although the
> parts list calls it a 2.2uF/50V - more likely).
>
> The 2100F is laid out a little different, with a 10uF on the
relay/grid/bias
> board.
>
> All comments appreciated.
>
> Rick, WD8JJA.
>
>
> ----- Original Message -----
> From: "Peter Frenning, OZ1PIF" <oz1pif@get2net.dk>
> To: "R_Davis" <WD8JJA@arrl.net>; "H & W Electronics"
> <info@handwelectronics.com>; <Fox_Tango@mailman.qth.net>;
> <amps@contesting.com>
> Sent: Monday, October 27, 2003 3:32 AM
> Subject: Re: [Amps] FL-2100F
>
>
> > Hi Rick,
> >
> > Check very carefully the two caps tying the grids to ground, I believe
> they
> > are C8-9 220pF in your version.
> > I had exactly the same symptoms in my FL2000B, with a set of new
bottles,
> > and not until I took it completely apart for conversion to a QB4/1100,
did
> I
> > find that one of these caps had blown - split completely open, but
> invisible
> > from the outside!
> >
> > 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: "R_Davis" <WD8JJA@arrl.net>
> > To: "H & W Electronics" <info@handwelectronics.com>;
> > <Fox_Tango@mailman.qth.net>; <amps@contesting.com>
> > Sent: Monday, October 27, 2003 4:15 AM
> > Subject: [Amps] FL-2100F
> >
> >
> > > Copy to AMPS reflector.
> > >
> > > H & W Electronics <info@handwelectronics.com>:
> > >
> > > Did you get a satisfactory answer to this, yet?
> > >
> > > I have an FL-2100B with similar symptoms.
> > > I used to have normal (~.090) bias, was able to drive it to > 500mils,
> and
> > > it put out 700 - 800 watts peak normally (more if I crowded it). Now
I
> > get
> > > only about 60 mA bias, can only drive it to 250-300 mA, and get 300
> watts
> > > out, at best. Also, driving it real hard, the LOAD control stays at
or
> > near
> > > 0.
> > > Those are my symptoms.
> > >
> > > Possible related causes: One time, I accidentally was tuning into the
> > > internal dummy load of my Dentron MT-3000A which is rated for 200
watts
> > and
> > > is protected by an internal fuse. I popped the fuse, but quit as soon
as
> I
> > > saw the SWR skyrocket.
> > > On another occasion, and I cannot remember if it was before or after,
I
> > > heard a "TINK" from the amp.
> > > Neither time did I notice these symptoms immediately, but it has only
> been
> > a
> > > few months since the blown fuse and the "TINK".
> > >
> > > Is the concensus that the tubes are now soft? Funny thing, I checked
it
> > > with one tube at a time, and with either tube in either socket, I can
> > drive
> > > it to over 200 mA, maybe even 250 with my FT-101E. But I can't get
500
> mA
> > > with both tubes in. HV still looks good @ 2400V, dropping to around
2200
> > > under load. ALC action looks normal, but at only about 300 watts out.
I
> > > haven't cut the ALC line yet to see if it is holding it back. I don't
> > think
> > > it is since I.C. on the exciter looks normal.
> > >
> > > Any suggestions before I by a new set of bottles??
> > >
> > > Rick, WD8JJA.
> > > ----- Original Message -----
> > > From: "H & W Electronics" <info@handwelectronics.com>
> > > To: <Fox_Tango@mailman.qth.net>
> > > Sent: Monday, October 20, 2003 11:29 PM
> > > Subject: [Fox_Tango] FL-2100F
> > >
> > >
> > > > Hi All!
> > > > Anyone ever had low reading on the bias current? This one does
only
> > > > .06 while spec is .09. What gives?
> > > >
> > > > Now, more than ever, QSL.NET is in urgent need of your financial
> > support.
> > > >
> > > > Please help QSL.NET by sending a donation now.
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