Tektronix 2465A Channel 1 problem
 

Hello,

I have the following problem on my 2465A.
When I am connect ch1 and ch2 to the calibrator, ch2 displays a
rectangular signal and ch1 displays something that becomes a
triangular signal when I increase the frequency.
I have put pictures on:

http://scalbert.dyndns.org/IMG_0004.JPG
http://scalbert.dyndns.org/IMG_0005.JPG
http://scalbert.dyndns.org/IMG_0006.JPG
http://scalbert.dyndns.org/IMG_0008.JPG

Sorry, pictures are not very good.

Any ideas ?

Thanks in advance,
Olivier

Tektronix 2465A Channel 1 problem
 

In fact it is like I have a capacitor in parallel on the ch1 entry.

Tektronix 2465A Channel 1 problem
 

wrote in message
oups.com...
In fact it is like I have a capacitor in parallel on the ch1 entry.

Yes, that would explain the integration (square to triangle).

Obviously, you have switched the probes?

Tektronix 2465A Channel 1 problem
 

" wrote in
ups.com:

Hello,

I have the following problem on my 2465A.
When I am connect ch1 and ch2 to the calibrator, ch2 displays a
rectangular signal and ch1 displays something that becomes a
triangular signal when I increase the frequency.
I have put pictures on:

http://scalbert.dyndns.org/IMG_0004.JPG
http://scalbert.dyndns.org/IMG_0005.JPG
http://scalbert.dyndns.org/IMG_0006.JPG
http://scalbert.dyndns.org/IMG_0008.JPG

Sorry, pictures are not very good.

Any ideas ?

Thanks in advance,
Olivier


you can remove the CH.1 attenuator,take it apart carefully(a plastic frame
retains the relays),and use an eraser to LIGHTLY clean the switch pads on
the ceramic substrate.
*Don't remove the gold plate.*
**Don't crack the substrate.**

the attenuators are succeptable to outgassing from plastics coating the
contact pads. The other part of the switches are the relays,I would not
attempt to clean those contacts,maybe spray with a zero-residue/zero lube
contact cleaner.

you have to remove the front plastic edge trim to access the screws to pull
the front panel,to access the screws to remove the attenuator.
there's a procedure in the service manual for atten removal.

New attenuators are no longer available;TEK does NOT support this product
series anymore.

--
Jim Yanik
jyanik
at
kua.net

Tektronix 2465A Channel 1 problem
 

Thanks

Obviously, you have switched the probes?
Yes, I have changed them and also changed the Volts/Div
:(

Tektronix 2465A Channel 1 problem
 

Thank Jim.

I will have a look this wee-end.
I have not the schematic of the scope. Do you think I can exchange
some parts of Ch1 and Ch2 to locate where is the problem ?

Olivier

Tektronix 2465A Channel 1 problem
 

On 1 Feb 2007 22:44:59 -0800 "
wrote in Message id:
. com:

Thank Jim.

I will have a look this wee-end.
I have not the schematic of the scope. Do you think I can exchange
some parts of Ch1 and Ch2 to locate where is the problem ?

Olivier

You can download a service manual here if you need one:
ftp://bama.sbc.edu/downloads/tek/2465a_2467/

Tektronix 2465A Channel 1 problem
 

" wrote in
ups.com:

Thank Jim.

I will have a look this wee-end.
I have not the schematic of the scope. Do you think I can exchange
some parts of Ch1 and Ch2 to locate where is the problem ?

Olivier


Ch.1 and Ch.2 preamps can be swapped.
That and the attens are the whole Channel 1 and 2.

IIRC,the BAMA site has the service manual for download.

--
Jim Yanik
jyanik
at
kua.net