Hello All,

I'm trying to repair a oscilloscope I have. The problem started
gradually and now will not power up.

Its a Tektronics 2246 100 MHZ oscilloscope. I have the factory repair
manual and schematics, but this problem is not covered in the manual.

Here is what happens. When I turn on the oscilloscope, I hear a
clicking from a relay. It clicks over and over and the oscilloscope
won't power on. It used to click a couple times, then it would power
up. So I'm looking for some kind advice on what might be wrong. I'm
thinking since it started gradually then stopped one day, perhaps its
a filter capacitor.

If you have some advice...I'll all eyes.

George

"oscllitr" wrote in message
...
Hello All,

I'm trying to repair a oscilloscope I have. The problem started
gradually and now will not power up.

Its a Tektronics 2246 100 MHZ oscilloscope. I have the factory repair
manual and schematics, but this problem is not covered in the manual.

Here is what happens. When I turn on the oscilloscope, I hear a
clicking from a relay. It clicks over and over and the oscilloscope
won't power on. It used to click a couple times, then it would power
up. So I'm looking for some kind advice on what might be wrong. I'm
thinking since it started gradually then stopped one day, perhaps its
a filter capacitor.

If you have some advice...I'll all eyes.

George



Sounds suspiciously like a switch mode power supply trying to start, but for
some reason, can't. Since this problem was a gradual thing, it certainly sounds
like electrolytic capacitor(s) in the power supply. Start there.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.

Thanks Dave,

Will do. One thing about this scope....its a pain in the a-- to take
the thing apart.

I'll report back with my 'success' if it so happens.

George

On Thu, 23 Oct 2008 13:27:45 -0700 (PDT) oscllitr
wrote in Message id:
:


Will do. One thing about this scope....its a pain in the a-- to take
the thing apart.

I'll second that! That power supply cage sucks to get into. I stay away
from any of the 22XX series

"oscllitr" wrote in message
...
Thanks Dave,

Will do. One thing about this scope....its a pain in the a-- to take
the thing apart.

I'll report back with my 'success' if it so happens.

George

I second the opinion that it's probably bad electrolytics in the power
supply. That happens often in Tek 'scopes.

I also second the opinion that Tektronix 'scopes are not known for falling
apart like a two-dollar suit when you want to disassemble them.

On Oct 24, 5:21*am, JW wrote:
On Thu, 23 Oct 2008 13:27:45 -0700 (PDT) oscllitr
wrote in Message id:
:



Will do. *One thing about this scope....its a pain in the a-- to take
the thing apart.

I'll second that! That power supply cage sucks to get into. I stay away
from any of the 22XX series

Check out :-

http://tech.groups.yahoo.com/group/TekScopes/

you might get some info

G ..

"Matt J. McCullar" wrote in
:


"oscllitr" wrote in message
..
.
Thanks Dave,

Will do. One thing about this scope....its a pain in the a-- to take
the thing apart.

I'll report back with my 'success' if it so happens.

George

I second the opinion that it's probably bad electrolytics in the power
supply. That happens often in Tek 'scopes.

Ditto.

I also second the opinion that Tektronix 'scopes are not known for
falling apart like a two-dollar suit when you want to disassemble
them.


the 224X series were not very serviceable scopes.
but it's not too hard to remove the power supply. Go in from the top.

--
Jim Yanik
jyanik
at
kua.net