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.
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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