On Fri, 25 Jul 2014 15:16:16 +0100, Baron
wrote:

Hi Chris,
That is a capacitor and should read O/C on an ohmeter. Lift one end
and re-check. You might find it's OK. In circuit measurements are
not always reliable !

Hi,

Thanks for the reply. I was thinking about it last night and I
figured it has to be C1006 leaking or shorted to ground. I just took
one end off and checked it - 120 ohms DCR. I also notice it's
slightly charred in one spot. So I will replace it (and I will
probably replace C1005 at the same time. My next question is what to
buy to replace it. It's listed as:

CAP, FXD, CER DI : 0.022 uf 20% 50V

Does that mean ceramic disc? I hope I can find one in that style
locally.





http://i.imgur.com/oCOyLOz.jpg (hv cover removed)

I turn the unit on and it doesn't complain. The controls are still
working fine. I check the new resistor and it's very hot. Measure
the voltage across it: 4.6v. If my math is correct, that's 2
watts.
Turn it back off and let it cool. Back on to check voltages:
Incoming voltage to new resistor is +7.4v to ground. LM324 pin 4 to
ground is 2.7v. Voltage pin 4 to pin 11 (across IC) is 10 volts.
Voltage pin 11 to ground is -7.43 volts. Voltage after R1026 is
-7.46
to ground. I desolder one end of R1026 and verify it is 10 ohms.
C1006 (the yellow guy near pin 7 of the IC) measures 47 ohms with a
multimeter. Shouldn't it read open? For reference, C1005 measures
about 100 ohms.

I'd just like to have an idea of what the problem might be before I
change any more components. Now I'm half wondering if it's the IC
and the fact that it's facing up and has a fan on it is allowing it
to
work properly. Anyway, thanks for reading my long story and I'd
appreciate any suggestions you have.

This is where I downloaded the service manual:

http://elektrotanya.com/tektronix_22.../download.html



















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