Faulty Tektronix TDS684A scope

[Angus Thomson]

Hi

I recently aquired an old(ish) Tektronix digital scope which is faulty and
does not start up; instead, the power turns on for 1/2 of a second then off
for 1/2 a second and a 'clicking' noise comes from the unit (this process
repeats). I take it this is a faulty power supply, possibly tripping out due
to excessive current being drawn. I have heard this problem has occured on
other Tektronix scopes; has anyone had any experince of this fault, and if
so, where exactly does the problem lie?!

Thanks!

Angus Thomson

[Robert Morein]

"Angus Thomson" <angi_...@hotmail.com> wrote in message
news:3g63b.54$7T3...@newsfep1-gui.server.ntli.net...

In general, anywhere.
Look for shorted tantalum caps.
If possible, disconnect subassemblies.

[Jim Yanik]

"Angus Thomson" <angi_...@hotmail.com> wrote in

news:3g63b.54$7T3...@newsfep1-gui.server.ntli.net:

Bad news here;TEK did not make service manuals with real schematics and
component parts lists for the TDS series scopes,and the PS were purchased
units.The TDS scopes are intended to be module-exchange service only,and
you will have to check the LTPS( long term product support) list at
www.tek.com to see if your particular scope model is still supported.But
TEK support will be expensive.

I would begin by using a DMM to check the rectifier diodes in the PS,and an
ESR meter to check electrolytic caps.

--
Jim Yanik,NRA member
jya...@kua.net

[Jim Yanik]

Fred Abse <excret...@cerebrumconfus.it> wrote in
news:pan.2003.08.28.18...@cerebrumconfus.it:

> On Thu, 28 Aug 2003 02:17:41 +0100, Jim Yanik wrote:
>
>> Bad news here;TEK did not make service manuals with real schematics and
>> component parts lists for the TDS series scopes,and the PS were
>> purchased units.The TDS scopes are intended to be module-exchange
>> service only
>

> Tek have gone right down the pan.
>
> I suspect MBAs at work :-(
>

Absolutely correct.

TEK sold off their ICO/hybrid manufacturing unit;had to drop an entire
product line as a direct result.
TEK laid off or reassigned much of their Service Support staff.
Manuals without the TEK schematics,parts lists,and the invaluable Circuit
Description section are MUCH cheaper to make.
And they don't have to distribute service data to service centers
anymore,as they closed those.Only the DC field office is left.

Beancounters :-(