I just finished repairing my 465 scope that had a similar problem. When powered up the trace would appear off
the left hand side of the screen. Turned out to be bad filter caps in the +5v and -8v supplies. Check the
supply voltages at the TPs, if 2v or more less that what it should be then replace the caps.
After looking at some of the Tek newsgroups I gather that bad filter caps are a common problem with Tektronix
scopes.

Richard WB8KRN


"Laurie Landry" wrote in message ...
My Tek 466 scope decided to misbehave. It will not display the horizontal
beam unless I press the beam finder. When I do it displays whatever I'm
looking at(eg: 7 Mhz sine wave) properly.
I'm quite familiar with this scope, but possibly doing something stupid.
Does anyone have any idea as to what the problem could be?
Thanks in advance for any light you can shed on the problem.

Laurie

Richard,
I believe that you are on target. I will try to find the TPs and verify
the voltages.
You mention Tek newsgroups. Can you tell me their location.
So far, they have eluded my searches.
Thank you very much for your suggestion.

Laurie

Laurie,
Here is one group on yahoo, http://groups.yahoo.com/group/TekSco...guid=145910120
Another is the newsgroup, sci.electronics.repair, this group covers everything under the sun.
I would tell you were to look but the 465 is different than the 466. Mine were on the "interface board"
which is located on the bottom of the scope, they are pins with eyelets in the ends. Voltage should be marked
on the pcb next to the test point pin.
Richard WB8KRN


"Laurie Landry" wrote in message ...
Richard,
I believe that you are on target. I will try to find the TPs and verify
the voltages.
You mention Tek newsgroups. Can you tell me their location.
So far, they have eluded my searches.
Thank you very much for your suggestion.

Laurie

Richard,
Thanks for the info on the groups. Regarding the voltages, they all
check ok except the -8v is something like -7.78volts. Whether this is
enough to cause the problem, is doubtful. Going through the service manual,
there is more information than I thought at first glance. However, it calls
for a lot of reading and my old eyes tire very rapidly!
There was a 465 on ebay today, but I lost out. The 465 has a few less
thing that can go wrong. But I suppose that digging into the 466 will help
me learn a few things!
Again, Richard, thanks for the advice.

Laurie

"

Richard,
Thanks for the info on the groups. Regarding the voltages, they all
check ok except the -8v is something like -7.78volts. Whether this is
enough to cause the problem, is doubtful. Going through the service manual,
there is more information than I thought at first glance. However, it calls
for a lot of reading and my old eyes tire very rapidly!
There was a 465 on ebay today, but I lost out. The 465 has a few less
thing that can go wrong. But I suppose that digging into the 466 will help
me learn a few things!
Again, Richard, thanks for the advice.

Laurie

"

Laurie,
Here is one group on yahoo, http://groups.yahoo.com/group/TekSco...guid=145910120
Another is the newsgroup, sci.electronics.repair, this group covers everything under the sun.
I would tell you were to look but the 465 is different than the 466. Mine were on the "interface board"
which is located on the bottom of the scope, they are pins with eyelets in the ends. Voltage should be marked
on the pcb next to the test point pin.
Richard WB8KRN


"Laurie Landry" wrote in message ...
Richard,
I believe that you are on target. I will try to find the TPs and verify
the voltages.
You mention Tek newsgroups. Can you tell me their location.
So far, they have eluded my searches.
Thank you very much for your suggestion.

Laurie

Richard,
I believe that you are on target. I will try to find the TPs and verify
the voltages.
You mention Tek newsgroups. Can you tell me their location.
So far, they have eluded my searches.
Thank you very much for your suggestion.

Laurie