Tektronix multiple mistakes in different copies/version of manual/schematic - Page 1
Forum section: electronics / general

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 09, 2017, 08:04:39 am
content: I have 3 versions of the service manual of my Tektronix oscilloscope. Its broken and I'm sort of trying to fix it, but also trying to learn how just the power supply board alone works is very complicated.And to my surprise I have found a few mistakes and inconsistencies between the 3 service manuals. Like mislabeling polarity on capacitors, mislabeling components 2 or more times so farAlso the schematic pictures aren't even exactly the same in these pdf service manuals.Well at least I have the SM for free and without waiting weeks. The power supply is overall probably the easiest part of this to learn as a relative beginner, I do not foresee learning much past that. And the major problem is not in the PS, but probably just in a big IC. When its time, I shall find out which is harder to find and fix, the PSU problem, or the channel 1 problem

author: David Hess
author_rank: Super Contributor
timestamp: February 09, 2017, 01:09:46 pm
content: You do not say which Tektronix oscilloscope you have but some had several minor revisions which were not always well documented in the service manuals and more than one major revision. It sometimes helps to study the service manuals for related instruments.

author: eugenenine
author_rank: Frequent Contributor
timestamp: February 09, 2017, 01:52:08 pm
content: Its not uncommon for manufacturers to make mistakes and/or make design revisions through the file of a product. Somewhere the three versions should have dates and/or revisions and/or a change log telling the differences. There may also be errata inserts that you may be missing as well.

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 10, 2017, 12:15:46 am
content: 1 MISTAKE is a pretty big 1, they had the polarity of the 2 main tank capacitors backwards. However I learned yesterday of a type of PSU where they would have the main tank caps wired that way, so perhaps the person making the schematic thought it was that type ? But IDK........I wish I had a free sandwich, but can't go there now,

author: David Hess
author_rank: Super Contributor
timestamp: February 10, 2017, 02:59:41 am
content: I have found mistakes here and there in their documentation. The most serious was swapping two aluminum electrolytic capacitors in the parts list of the 2465 series and maybe getting the polarities wrong. The error I found a couple days ago was labeling the 1N3890 diode as 500V instead of 50V in one of the later 7000 parts lists.If you said which instrument or schematic had the error, then we could review it.

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2017, 08:43:17 am
content: Quote from: lordvader88 on February 09, 2017, 08:04:39 amI'm not sure why you are telling us that. It contains no information that will help us or help us to help you.Products which have a long life-cycle inevitably contain changes and mistakes. Should you be more concerned about short life-cycle products that become unrepairable, or products where the manufacturer doesn't admit/publicise changes?