Polish storage Oscilloscope KR-7401 schematics, manuals - Page 1
Forum section: electronics / testgear

author: klimm
author_rank: Contributor
timestamp: May 27, 2018, 04:21:31 pm
content: Hi all,I am in search of the above docs, as I do have the thing not working, of course, but no info about it.It uses the RFT B13S13 CRT but also about this one can't get any infoKind regards,Gelu

author: Pinkus
author_rank: Frequent Contributor
timestamp: May 28, 2018, 07:48:49 am
content: How about some photos from outside and also inside? We might be able to recognize it as a different brand which would make it easier to find documents.

author: klimm
author_rank: Contributor
timestamp: May 30, 2018, 10:02:19 am
content: There is no such other brand, Pinkus

author: fejkblad
author_rank: Newbie
timestamp: May 30, 2018, 10:22:39 am
content: Hi,In this thread you can find pictures of schematics:https://www.elektroda.pl/rtvforum/topic2970035.html?sid=91a14c818ffc3c30c08f228432055734

author: Pinkus
author_rank: Frequent Contributor
timestamp: May 30, 2018, 10:25:57 am
content: You never know. Maybe somebody recognizes it as a scope also being sold by brand xyz.btw: did you ask the manufacturer?At least in their brochure they are proudly referring to their invention from 1986http://radiotechnika.com.pl/component/tinydoc/document/124?format=rawpage 5, bottom right corner. So chances are not too small that they do have some documentation somewhere.

author: klimm
author_rank: Contributor
timestamp: May 30, 2018, 11:49:23 am
content: Fejkblad, Pinkus,Thank you for your help.It was maybe not polite from me not to mention that I really searched the internet before posting.Who would believe me anyway.Of course, before posting here, I did it on romanian forums, and on elektroda.pl. I find there 2 threads dealing with repair/restoration of this oscilloscope Gizmon and Milik. There was some info but didn't help much, as mine has different symptoms and the guys there had schematics at hand. So, I opened a thread on elektroda.pl asking for docs. No answer yet. I also wrote an mail to Radiotechnika asking for docs. I also find their flyer mentioning the KR-7401. Well after waiting for more than a week, I decided to also ask here, seeing some of you guys are from Poland. I now have a thread on Robotrontechnik forum that mostly deals with ex DDR stuff, in search of data for the CRT the RFT's B13S13 which is a storage CRT.During the cold war, no western country would buy from eastern ones, technology, only dumping consumer goods.So, again, no chance that we could discover the KR-7401 under other name in the western worldWell, opening the machine, I determined by eye the pins of the CRT and I supplied the filament with 6.3V. Measured a small current between cathode and control grid I=40uA after running for about 3 minutes. Not much life in it I would say, but I still have the option of trying to regenerate the cathode for about other 500 hours of working which for my needs as radio amateur is really ok. I need a scope not so often and it is the provocation of repairing it instead of making a postal box of itThanks again, Gelu, YO5TC

author: Jacon
author_rank: Regular Contributor
timestamp: May 30, 2018, 08:03:50 pm
content: Quote from: klimm on May 30, 2018, 11:49:23 amWell, not me, obviously...As you should find this site:http://www.instrukcje-schematy.pl/containing countless documentation pieces regarding almost every T&M equipment produced here.But they're not free to get, for sure...

author: klimm
author_rank: Contributor
timestamp: May 31, 2018, 01:08:23 pm
content: Thank you Jacon,I was not aware of the site. I wrote an email and I quickly got the infos in polish, scanned at a relative low quality . Too bad the phots were not cleaned before transformed in PDF, an this makes the document hard to read.The price was really ok and overall, I have more info than before.Thank you againGelu, YO5TC