Tektronix 2465B Scope Overall Low Voltage

[JE610]

Hi all,

First post here. I recently came into possession of a Tektronix 2465B Scope (#B062849) and don't know anything really about it. I brought it home and when I powered it on all of the LEDs illuminated, a beam displays for a split second, and then both the LEDs and beam disappear. The lamp for the CRT stays on but it just flashes rapidly. After checking voltages at j119 it seems that all are low and out of range. I'm not sure what this would be attributed to and would appreciate a little insight and possibly thoughts on how to at least get it to a point where it will run its diagnostics. I've never really delved into something of this caliber so any information would help!

Thanks!

-J

[tautech]

Welcome to the forum.

Great resource for these scopes here:
https://www.eevblog.com/forum/testgear/tektronix-2465b-oscilloscope-teardown/

[Testtech]

This model will virtually always need to have the PSU recapped. Resources here, and on Tekscopes@groups.io

[med6753]

Is the +10V reference correct? It should be no less than +9.9V and no greater than +10.1V. If it's off spec all the voltages at J119 will be incorrect.

While your issue is most likely capacitor related there could be other issues. But a total re-cap of the PSU is a starting point. Details of performing the re-cap can be found here:

https://www.eevblog.com/forum/testgear/tektronix-2465b-oscilloscope-teardown/msg1658102/#msg1658102

[JE610]

No, 10v ref is off by quite a bit. I want to say it was dropping to 9.52 at lowest. When testing voltages there was a noise like something shorting every so often as well. Just doing a quick visual inspection it doesn't look that any caps are leaking terribly. There doesn't seem to be corrosion or spots on the board indicating a leak. I can try and take a video of it powering on at some point.