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?
> >
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