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-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
musicamex@...
Sent: Tuesday, June 19, 2018 2:50 PM
To: [email protected]
Subject: [TekScopes] Tek 465 no display

Hi, I am a music teacher in Mexico to help keep kids here. I also
teach how to repair and build musicians gear including tube amps. I
recently acquired a Tek 465 donated to the program. There is no screen
display and despite the 2 fuses are good and the power switch on light
does show power is getting to at least part of the scope.

I am not in the same league as most on this site. The 465 makes an
average tube amp look like a lightbulb by comparison. I downloaded the
465 manual and service manual but really would appreciate a little step
by step troubleshooting help. I always suspect electrolytic capacitors
over 10 yrs old and read that the tantalum caps are also unreliable.
The boards look like the New Mexico balloon fest in places, so, where
to start? The fuse inside the 465 tests 24.5 V on both sides of the
fuse, but i couldnt find a diagram with test point values. Also it
doesn't appear that the filament in the CRT is lit and the fan doesn't
activate when the power switch is turned on like with my TEK 468. The
465 looks like it wasn't abused and has an IBM sticker on it. It looks
like one of the filter caps was replaced as it has a blue plastic cover
unlike the adjacent aluminum can caps. I haven't disassembled or
unsoldered ANYTHING yet. I understand that the 465 is one of the holy
grail TEK scopes and i think it might outlast me if I can get it
working again.

Would someone please walk me through getting the display to come on?
The main thing we currently use oscilloscopes for is to track a
frequency generator audio signal through a tube amp, looking for a
distorted sine wave to help isolate where the problem(s) are. So
highly accurate calibration isn't necessary if there is a good clean
sine wave when connected to the wave gen.

Thank you in advance, Russ