Well, if the shunt were open you would see a pinned meter and it would
possibly burn it out (which would leave you with a dead amp).
The switch is the most likely of what you have mentioned, but without
knowing the maintenance history of the unit it is just guessing. I suppose
it is possible that the shunt failed and was replaced with a jumper.
Get your ohmmeter, open the amp up and start tracing (be sure the caps are
dischared first of course). If you don't have the book there are copies of
it on the internet.
The good news is the numbers you have indicate a working amp. With good
tubes and line voltage you should be able to get about 600 watts out with
100 watts drive, probably a little less on 15 and 10. Remember this amp is
rated for SSB and cw and you don't want to run RTTY or any other continuous
mode at that power level for very long at all.
Sounds like you got a pretty good buy though!!
Chris, AB6QK
>Date: Sun, 11 Sep 2016 11:22:38 -0400
>From: "Ken Durand" <N4zed@comcast.net>
>To: <amps@contesting.com>
>Subject: [Amps] FL-2100B Plate Current
>Message-ID: <000801d20c40$5581b5d0$00852170$@comcast.net>
>Content-Type: text/plain; charset="us-ascii"
>I purchased a FL-2100B amp yesterday at an estate sale. @ $190 I thought it
>was worth the chance. It was from a SK and the station looked as if the amp
>was being used when the station was shut down. I have no idea how long.
<<<<snip>>>>
>I got the unit home pulled the cover off to check what voltage it was wired
>at and replaced the plug with one that matched my 220v receptacle. Plugged
>it in..OK someone is screaming now that I should have used a variac.I don't
>have a 220v variac. Crossed my fingers and flipped the switch. The unit
came
>on with no fireworks, HV at 2400v. HV meter steady. I let the amp idle for
>about 3 hours then turned if off and attached the coax, ALC and relay
wires.
>The amp was attached to a dummy load and I keyed the exciter driving the
amp
>with 20w, still no fireworks. As I tuned the plate and loading caps per the
>manual I didn't see any plate current, I was getting amplification but no
>current. First thought was the meter is shot, but when the switch is
flipped
>between SWR and Plate current the meter swings as it should on SWR. I tuned
>it by peeking the rf out. I know I should be dipping the plate current.
>I used the amp for a while this morning and it worked fine, no distortion
>and a clean signal on the waterfall. I am only driving it at 40w and get
>around 300w out. Tubes look original.
>So what's up with the plate current?
>Switch or the Shunt?
>Thanks guys.
>Ken
>N4zed
>http://www.qrz.com/db/N4ZED
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