*** Looking at all of the pieces with a magnifing glass?
>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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>> > > >
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>> > >
>> >
>> >
>> >
>> >
>> > _______________________________________________
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>> >
>>
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- R.L. Measures/Rich..., AG6K, 805.386.3734, www.somis.org
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