| jasont |
I have just been given a Tektronix 2225 Oscilloscope which has a crackling noise coming from the back of it.
I took the case off the noise is coming from the rear of the scope from either a black box connected by a red wire to the front of the tube or a small transformer. I didn't want to start poking about, the black box says 2KV in this area the small transform says 100V DC in this area.
Any thoughts on whats causing the crackling, where to get a service manual, spare part or if i should throw it out. |
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| Bensen |
Hi Jasont,
I bought the same scope two weeks ago on Ebay (240euro incl probes).
I'm also interested in any reply's of this thread, if one day I've the same problem. With the service manual I'm glad to help you. Here is a link of a scanned version of the manual.
http://21944.gel.ulaval.ca/travaux/...scilloscope.pdf
Ciao
Ben |
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| GaryB |
| quote: | Originally posted by jasont
I have just been given a Tektronix 2225 Oscilloscope which has a crackling noise coming from the back of it.
Any thoughts on whats causing the crackling, where to get a service manual, spare part or if i should throw it out. |
You might look at the following thread where people reported that the IEC filter in a Tek 2235 could not stand the European
mains voltage of 240v. Removing the IEC filter fixed the problem.
http://www.diyaudio.com/forums/show...5385#post325385
---Gary (no problems with my 2225 in New York) |
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| Sch3mat1c |
...Could always be HV problems... my 475 has leakage around the CRT's HV connection... need to put some silicone on that some day...
Tim |
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| geoffd |
Ben,
I had a look a the PDF file and it is the Operators Manual, do you have a copy of the Service Manual with the circuit diagrams etc?
I have just brought a second hand 2225 from eBay and I need the calibration instructions.
Best ishes
Geoff |
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| Bensen |
I'm sorry Geoff. But I don't have a service manual or circuit diagrams off this scope.
Hope you'll enjoy this scope. Mine works great, and it's easy to use.
Best regards
Ben |
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| geoffd |
Thanks.
There was one on eBay, but I had to go out near the end of the auction.... I got beaten by 5 cents!
Cheers
Geoff |
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| jackinnj |
| you can get reasonable priced TEK service manuals from www.w7fg.com |
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| tekman |
2 GaryB, Bensen:
Reason for the noise is most often this one:
Problem near HV multplier, most often dust and dirt accumulated. Hint: Open the scope, do careful cleaning wit ha soft brush. Switch of at least 5 minutes before opening to let all caps dicharge forshure :)
BTW: I can't recommend the IEC filter completely. It helps to keep the SMPS noise from the scope supply transmitting via the mains cable - causes often strange side effects in a measurment setup (most likely your own. Hard to diagnose). Replacing the original filter with a good (european 240V standing) mains filter is recommended. Like the ones from "Schaffner", switzerland. Any proven filter (VDE, CSA or what is apropriate for your country) brandname filter will be fine. As long at it can be fitted and takes at least 3 A, max 5 A. More is "overkill" and unnecessary expensive.
2 Sch3mat1c :
I can't recommend silicone in this area. But careful cleaning (isopropyl) and removin all dirt & dust near the HV and along the cables really helped (I had to repair appr. 15 of these). |
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