[GreenKeys] Tek 485 help?

[Steve Ripper]

Here is a link to a thread for a power supply problem very much like yours.
Especially tic-tic-tic sound you hear is explained.

http://www.dslreports.com/forum/r25550083-Tektronix-485-no-power-up

And here is a link to the service manual (30MB)

http://bama.edebris.com/manuals/tek/485/


Steve R.


On Sun, Feb 18, 2018 at 9:27 PM, drlegendre . <drlegendre at gmail.com> wrote:

> Anyone here familiar with the power supply voodoo in the Tek 485? I have a
> scope here that was running ok, then suddenly the display went out of focus
> - the traces became very wide and indistinct. About a minute later, the
> entire PSU shut down.
>
> About all that's working at this time is the main DC supply, the one that
> drives a little neon relaxation oscillator. None of the 5V / 15V / 9V etc.
> points are hot, just a little noise on those. I can also hear a faint
> 'tic-tic-tic' from one of the PSU boards.
>
> This unit is above my pay grade, and I'm not sure how to t-shoot it. About
> all I know is that the main DC supply is up, and everything else is dead.
>
> Thanks for any help.
>
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-- 
Cheers,

Steve Ripper
steve.ripper at gmail.com
248-787-0705
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