Need help with or manuals for Tektronix 2211, and Kenwood CS-5350 Oscilloscopes - Page 1
Forum section: electronics / testgear

author: Treehouseman
author_rank: Unknown
timestamp: December 30, 2013, 03:48:45 am
content: Sorry for the wall of text >_>I nabbed from the local community college's junk pile 3 Kenwood CS-5350 and 2 Tektronix 2211 Digital storage scopes. I got no documentation other than "bad" written on most and one or two of the kenwoods had "unstable voltage reading" on them. I can't find ANY manual for the Kenwood scopes, and barely any information in general, I'll describe my findings/issues with them after the Tektronix ones as those are personally more valuable being digital storage unlike the kenwoods, all scopes are 50 MHz 2 Ch, but the kenwoods do have a limited function third channel.The Tektronix 2211 scopes seem to be in fairly good shape, one of them I could find no issue other than the control knob for the cursors seemed a bit stiff and acted a bit funny, but still very usable, the other seems to have a malfunctioning probe test circuit, instead of the rated 1 kHz it only reads ~917 Hz. I did some searching and was only able to find 2211 specific manuals on ebay, that is both the user manual and the service manual. These also have a GPIO/RS232 output function to either print or send to computer but I have been unsuccessful at getting a RS232 connection to my computer working, I feel that I'm never going to make any progress just flipping the parameter switches not knowing what they do, I tried a similar model (2210, 2213, or 2220 I think) to go off of but had no results. I also saw that in the official "Grabber" program it didn't have this model listed. I ran the software for these older scopes in a windows xp VM with a KeySpan/TrippLite USB to serial adapter using the Null Modem cable specified on the Tektronix site for the similar models (I did make the cable so it's possible that's the issue but I do not have a proper one and do not wish to buy one unless I know it'll work if possible). These scopes, including the kenwoods were very clean on the ones I have opened up, seems they were deemed broken or the like and shelved away or kept very clean or in a very clean environment. If anyone has the manuals and is willing to share I'd really appreciate it, but if no one has them, I guess I'll have to purchase them from ebay.Now for the Kenwood CS-5350 scopes it gets a bit more tricky. No matter how I search it I can find barely any scraps of info on them online, I saw one site that mentioned this model in one section of the page and at another said they were B&K rebrands, from there I went searching for B&K lookalikes, which found nothing from B&K that matched. What I did find though was a spitting image down to the smallest text under the brand Leader on the model LS-8106A which cosmetically the ONLY difference is the sticker above the display having a different brand/model. The confusing part is that this Leader model is a 100 MHz scope and not a 50 MHz scope, and there's not a 50 MHz model that looks like it. I tried finding service and user manuals for it but didn't really come up with much, or at least anything helpful. Unfortunately these are the really tricky ones, 2 of them (at least) have a bizarre issue with the internal voltage reading being off in the auto-detect mode, when using the cursors manually it reads just fine. Though on one of them it seems that it also throws off the voltage division reading as well, but the fluctuations in both do not affect the waveform displayed in any way, it is isolated only to the on screen text. It also seems that at times it can be triggered/modified by wiggling or twisting the probe plug on the jack, but for the record the BNC connectors do not feel loose at all. I'm thinking this may be an issue of either oxidation (which all the scopes seem to have on all BNCs, I tried contact cleaner, but I'll have to get some fine sandpaper and go at them gently it seems) or an issue with the internal voltage detecting circuit either making a connection if it's a circuit all it's own, or just reading the waveform. I attempted removing the face plate to get at the BNC connector board the other day but I couldn't see an easy way to get at it without possibly damaging a board, so I'd really rather have a proper service manual to tell me how to do it before I go breaking things. Now the third scope is a bit of a puzzle, though it may be simple, just complicated without a circuit diagram. This particular scope has a display issue, it is off center to the right and everything is blurry, on this particular scope the trace does not affect it, but on another that was in the junk pile I remember that when the trace was positioned to the left of the text (just offset to the left with the normal position knob) when it was on a large time base (pretty much longest time division, couldn't read it to know) as it would start from the left it would correct the garbled and blurred text until it was even with the start of the text, then it would mess up again. When turning the scope off you could see the center of the screen glow as the heater began to cool, so it's not a messed up CRT I think, but rather a display board issue, but none of the pots, (or very few in weird spots) are labeled. I'm at a loss of what to do, it's possible it also has the same voltage issue, but I cant tell unless I can read the text and see enough of it to show the text in a first place.I'll add pictures for what I can, if anyone needs further information let me know and I'll do my best to get it to you, 2 of the Kenwoods (the bad display one, and the one that would occasionally have a bad division reading) and one of the Tektronix (the one with the stiff cursor knob) will be going to storage soon, but the remaining two scopes are staying in my room, I just don't have space to keep all of them in here for the long term.You can find a video of the one Kenwood with the display issues doing its... thing.... here:http://youtu.be/3qmf4Yx3x6YI tried uploading them, but it just after a while I was greeted with a blank new post page (I'm thinking a file size issue), but you can find pictures here:http://imgur.com/a/SLfHh

author: Eisenstein
author_rank: Newbie
timestamp: December 30, 2013, 04:34:44 am
content: I found SMs for a Tek 221 and a Tek 2213 here:*http://elektrotanya.com/tektronix_221.pdf/download.html*http://elektrotanya.com/tektronix_2213_oscilloscope_sm.pdf/download.htmlI don't know if those are helpful, but FYI just in case.Also, USB-RS232 adapters aren't very nice in playing with some RS-232 devices since they don't use the native protocol and instead emulate it (if I understand correctly). Your best bet is to use an older machine with a native RS-232 interface or a card such as this in a newer laptop:*http://www.amazon.com/dp/B0026713WE/Hope this helps.

author: Treehouseman
author_rank: Unknown
timestamp: December 30, 2013, 04:44:56 am
content: I think I've taken a look at that same 2213 manual, but it didn't show as a duplicate download so I'll take a skim through it as well as the 221. As for the native RS232, I know that in some situations it can have issues with USB adapters, and I do actually have an old HP laptop with one on it, but I'm trying to avoid having to get it going, it's slow as molasses, and I cant remember for certain if it's 32bit or not (the programs are dos 16bit), and it's windows 7, so even if it is 32bit I may still end up having to load up a VM on it, I no longer have a computer with XP, at least a fully functional one. Though in my experience the keyspan adapters seem to almost always work, and the program did in fact latch onto the port as the status LED on the adapter went solid to indicate use, but it never transferred any data :/Guess I'll have to test it when I have some time, because it's definitely not going to be a fast process.

author: Bored@Work
author_rank: Super Contributor
timestamp: December 30, 2013, 07:26:36 am
content: In the old days we used to test and rig RS232 interfaces with one of these breakout boxesThey don't contain any black magic, they just make it convenient to play with an RS232 interface. If you don't have one you can build your own. Or just use a multimeter or a LE Dwith a 860 kOhm resistor to figure out Tx and hardware flow control pins, if in use. You can use a second oscilloscope to make an educated guess about the baud rate - in case the oscilloscope under test can be made to send something (might require to have the flow control rigged).