hybridfree/eevblog-posts huggingface dataset:
TDS3012B Ethernet connection failure - Page 1
Forum section: electronics / repair

author: Galen
author_rank: Regular Contributor
timestamp: June 22, 2020, 11:33:20 am
content: My TDS3012B and 3014B all can't connect computer through the network port on the back, using a crossover cable.I acquired a TDS3012B with blank screen, after repaird (75.757 oscillator dead, use a 75M now), I tried the connection using the same cross over cable, it connected with no problem. So the cross over cable is good.Then I switched this machine's power module (including some network circuit on it) to the no-connection machine, still no connection. So the problem is not in the power module , should be in main board.Of cause I copied the network setting in the scope, still no joy. Ping shows no reply.Problem solved. This is caused by corruption NVRAM. Use a good NVRAM file and burn in, network works.
TDS3014 - screen freezes on startup - Page 1
Forum section: electronics / repair

author: e_berdanos
author_rank: Newbie
timestamp: April 28, 2021, 01:18:24 pm
content: Hi Everybody,I have an old TDS3014 that has just broken down in 2021! TDS no longer starts completely and stops at the logo screen.I suspect the RTC chip DS1742 who include lithium battery for operate about 10 years.See the attached file for more details for the battery replacement in the DS1742 chip.ThankEric

author: Teichhermelin
author_rank: Regular Contributor
timestamp: May 06, 2021, 05:39:21 pm
content: I also unsoldered the chip on my TL5204B and secured it with the data I / O. Then I soldered in a socket and now change the circuit every few years and secure the content beforehand. Works wonderfully!

author: james_s
author_rank: Super Contributor
timestamp: May 06, 2021, 05:49:14 pm
content: A dead DS1742 does not normally prevent the scope from booting, it only makes the clock stop keeping time and stored settings are lost. Try holding down B-trig while turning the power on, that should clear and initialize the NVRAM in case it is corrupted in a way that somehow prevents booting.
TDS3034  Timebase Adjustment Erratic - Page 1
Forum section: electronics / repair

author: richsf
author_rank: Contributor
timestamp: February 05, 2025, 04:25:40 pm
content: My timebase control on my TDS 3034 adjustment going CW, will suddenly reverse to a slower sweep rate when I try to adjust to a faster. What is the fix for this ?Is this control a quadrature type digital input ?

author: benj38
author_rank: Frequent Contributor
timestamp: February 05, 2025, 09:24:29 pm
content: Almost certainly just a dirty rotary encoder. Search the forum for information on fixing those.

author: richsf
author_rank: Contributor
timestamp: February 06, 2025, 11:54:35 am
content: Thank you benj38. I did find an old post on this. Also a picture athttps://www.artisantg.com/itemimages/Tektronix_679_4119_00_View1_201811716235.jpgwhich is helpful to see what I will find when I get inside. It looks like all the front panel controls are the same type with the actual quadrature contacts as part of the PCB and the plastic part might just have the wiper. I could not find the replacement part number for sale anywhere and maybe that wouldn't do any good anyway.Is there a schematic of the front panel PCB somewhere ?old post ref:https://www.eevblog.com/forum/repair/tds3000b-tds3054b-strange-type-rotary-encoder-repairreplacement/?allAny additional advice or information appreciated. I'd love to see the PCB pattern under the plastic encoder.

author: benj38
author_rank: Frequent Contributor
timestamp: February 06, 2025, 01:02:05 pm
content: In my experience fixing these, you just need to get in there and clean them. Unless a Gorilla abused the encoder, you will not need a replacement part, nor do I see a need for a schematic (which I have never seen in the wild for the TDS3000 scopes - the service manual has no schematics).I never had to drill an access hole for the contact cleaner as some people suggest. I remember that once you gain access to the PCB it is quite easy: generously spray a good contact cleaner between the PCB and the encoder, and it should work its way in. Worst case, remove the encoder, clean, and reassemble it.BTW, if you have never opened one of these scopes before, the most puzzling part is opening the case, which is a very unique procedure. Get the service manual (not hard to find on the web) and follow the instructions there.

author: richsf
author_rank: Contributor
timestamp: February 06, 2025, 01:14:36 pm
content: Thanks for mentioning that I may not have to take the control off the PCB or drill a hole.I did replace a display once, years ago, it will come back to me once I start the task.

author: richsf
author_rank: Contributor
timestamp: February 06, 2025, 04:42:17 pm
content: Just taking the knob off and spraying close I was able to get contact cleaner into it, seems to have worked for the time being. Just lucky, we'll see if it lasts.
TDS3034B (TDS3000) Dead white screen only - Page 1
Forum section: electronics / repair

author: Cyclotron
author_rank: Unknown
timestamp: July 26, 2025, 07:18:36 pm
content: So far, this will be an easy win, though it comes with some curiosities.I picked up this TDS3034B for parts/repair. Turn it on and it would only show the white screen backlights.I'm not an expert on the TDS3000 series, but I've repaired 5 so far and put them back to work. To the best of my knowledge, it was built in late 2004, and it's one of the new TDS3000s I've worked on.Upon opening the unit, I immediately found that the ribbon cables for the display and the power supply for the main board were disconnected. The display cable's retention clip is missing. (I have one) I put the cables on, and it boots normally, as far as I can tell. I attached a probe to input one, and the system rebooted. Once back up, I tested to see if the unit could display a signal, and it could. I determined that the first probe socket is loose, and these attempts to install or remove a probe cause a reboot.I've decided to disassemble, clean, tighten, and check all connections. I may have tried a sell test, but I am concerned that the shorting or whatever is causing the reboot could cause more damage.At this point, I have it in parts and have discovered a curiosity. The hybrid for channel 1 is different than the ones on the other channels. I've attached photos. There's also some flux on the board around a couple of what I think are quad SPST switches.I've also noticed corrosion on the surrounds for the BNC connectors and the Electrolyte capacitors are different on the main board from any I've seen in others.As I work towards getting this unit up and running. The hybrid in channel one is actually an older one, I think, but I'm not positive.

author: sprit
author_rank: Regular Contributor
timestamp: July 27, 2025, 03:07:24 pm
content: HiWhen you start it, is there a square wave on the front Cal pin? Have you tried checking the LOG with uart? Also check the main quartz on the mainboard. This mainboard has been repaired so I think it's quite difficult to find the starting point. As usual, check voltage -> main oscillator quartz -> check probe out pin.
TDS3054B SPC failure - Page 1
Forum section: electronics / repair

author: Cyclotron
author_rank: Unknown
timestamp: March 16, 2025, 09:50:36 pm
content: I attempted a SPC on a used TSD3054B that I bought. It says it has been thousands of hours since it was run.The SPC fails with the message to check the error logs, but I either cannot find the right place to check or there are no errors in the log.I've pulled the diskette drive and done a diagnostic, so I got a failure on the disk drive, which shows up in the error log for the diagnostic.I replaced the hybrid relays, and the CAPs in this unit are known to be a problem or have become one, so I swapped those out, too.The Scope appears to run well, but the readings are a bit off compared to one of my other scopes, so I wish to run the SPC.Do you have any suggestions? I find the error log under the "System->diag" menu but don't see any elsewhere.

author: Cyclotron
author_rank: Unknown
timestamp: March 17, 2025, 03:05:37 am
content: Screen shot
TDS310 Boot issue - Page 1
Forum section: electronics / repair

author: beubeu
author_rank: Newbie
timestamp: March 17, 2022, 09:34:45 pm
content: Hello all,I'm here because I bought a Tek TDS310 some weeks ago, all was fine since.. But today, something wrong appear !There is an issue on the boot :When I plug the 220v cable, the TDS start immediatly, without press the power button on the front panel. After the boot, the scope work fine, without problem. If I push the power button for stop the scope, sometime the scope restart after the pwoer down, sometime the scope stay in "standby" and I can"t power up again without witing 2-3 minutes !It is a very strange issue :/My opinion, is that maybe the power button is in bad condition (dust ?), or the PSU is in fault (caps ?)At this day, I have not opened the unit, i prefer ask here if someone has already seen this issueHelp me please, i love my scope ^^PS : there are no error codes in the log

author: beubeu
author_rank: Newbie
timestamp: March 18, 2022, 08:43:58 am
content: Hmmm I checked some topics, and the issue could be the switch button with the "carbon contact".I will check this way this week end, but.. In this case, how can I repair this switch ? Carbon switch is not commun :/

author: beubeu
author_rank: Newbie
timestamp: March 18, 2022, 07:18:44 pm
content: Re,it's me again ^^I opened the scope, and check the power switch. It seems ok, nothng strange.Next, I opened the PSU... And I think that the issue is here.I tryed to follow the track of the "ON/OFF" signal, but the track desapear under some component and it is hard to see where he go !The big problem is around a LM393, there is corrosion, I don't konw if the root of this corrosion is water or other liquid, I don't see anything strange on the cover of the PSU...This PSU is manufactured by an external constructor, and I don't find the schematic... The tracks around the IC is very fragile, and the it will be hard t solve this issue :/Edit : I tryed to follow the ON/OFF track, and.. the track finish to this LM393. So next step is to work on this aeraGood job for this week end !

author: beubeu
author_rank: Newbie
timestamp: March 21, 2022, 07:25:39 am
content: ReIt's a success ! TDS repairedThe root of the issue was the "big" secondary caps (1000u/25v), it seems OK, but after removing, I seen that the content leaked ! And all tracks below the caps was cutted or in very bad condition :/So no other solution that add wires below the PCB for recreate the tracks ! You can see that on the pictures. Now all works fine yeaahh xD
TDS320 will not power off - Page 1
Forum section: electronics / repair

author: jpirok
author_rank: Newbie
timestamp: June 12, 2017, 02:11:15 am
content: So, I just got my hands on a nice looking Tektronix TDS320 this weekend. When I plug it in it just starts right up, but when I press the Power/Standby button, I get no response. Everything else I've poked at on it has worked fine. I can't find schematics on Tek's website and wondered if anyone else had experienced this?Thanks in advance!

author: Ushiwaka
author_rank: Regular Contributor
timestamp: June 12, 2017, 02:43:31 am
content: Crack it open and check that button. It might be broken.

author: xwarp
author_rank: Frequent Contributor
timestamp: June 12, 2017, 03:08:09 am
content: Word of advice for you, look through some of the search results as shown by clicking the link below:https://www.google.com/search?q=tektronix+tds+capacitors&ie=utf-8&oe=utf-8Next, I would expect something going on with the front panel and the touch switches. My TDS460 had issues with the buttons not working properly and it turned out that in addition to a leaky cap on the front panel board, there was a trace dissolved on it.ALSO.... be VERY CAREFUL on the traces for those bezel switch traces. Alcohol will wipe them right off. I made the mistake of using 100% IPA and it wiped them right off. Did not much matter at that point because one trace had already been damaged previously. I cured the problem by replacing the carbon traces with conductive epoxy.

author: John Crighton
author_rank: Newbie
timestamp: March 01, 2020, 12:13:02 am
content: ALSO.... be VERY CAREFUL on the traces for those bezel switch traces. Alcohol will wipe them right off. I made the mistake of using 100% IPA and it wiped them right off. Did not much matter at that point because one trace had already been damaged previously. I cured the problem by replacing the carbon traces with conductive epoxy.Hello xwarp,I made the same mistake, used isopropyl on a cotton bud and the little golden zig zag dissappered.May I have some details on how you repaired the traces with conductive epoxy?Thanks,John

author: james_s
author_rank: Super Contributor
timestamp: March 01, 2020, 02:14:57 am
content: I had to repair a damaged trace on the flex in a TDS410, I used some carbon paint that was sold for shielding inside electric guitars. Those flex boards are fragile, in the service manual it warns to not even touch the contacts.

author: Smoky
author_rank: Frequent Contributor
timestamp: March 01, 2020, 05:17:54 am
content: I can confidently say that I've been inside of a TDS scope once or twiceI found the fault for buttons not working being caused by "glazing" over the carbon contacts embedded in the flexible rubber gasket that surrounds the CRT.I wash the black contacts with lacquer thinner and lightly wipe off the trace "impression" from the surface with a small piece of 2000 grit 3M wet/dry sandpaper while it's still soaked.It seemed to work every time I tried it.
TDS430A Acqusition Memory information? - Page 1
Forum section: electronics / repair

author: rjmusto
author_rank: Contributor
timestamp: July 01, 2023, 03:44:34 pm
content: Hi all,I have a Tek TDS-430A scope that fails the acqui test on start-up showing a Channel 1 memory fault. Everything else passes.I have so far been searching in vain for any information that would help me identify which chips on the acquisition board are the memory for Channel 1.Anybody here able to help?Thanks a lot,Ralph
TDS460A - PS2217 power supply clicking when off? - Page 1
Forum section: electronics / repair

author: Fractal
author_rank: Contributor
timestamp: October 04, 2023, 09:13:54 pm
content: Hi there,I got this scope I just finished repairing after replacing a completely rotten backplane boardPut it all back together, everything seems to be working fine,But then *soft* turned off I can hear something clicking insideI've measured the mains and it appears to be pulling 6W in that state>>> Is it a normal thing for this power supply? Or could there be an underlying issue?I guess I could live with it but it would get pretty annoying and the kachonk is real hard to access at the back with my setupThanks!Cheers,__Yves

author: Fractal
author_rank: Contributor
timestamp: October 07, 2023, 09:09:40 pm
content: plop! nobody?
TDS5032B - Page 1
Forum section: electronics / repair

author: HuuPhuc
author_rank: Newbie
timestamp: September 30, 2024, 02:14:43 pm
content: Hi,I need help to restore the HD for my Tektronix model TDS5032B. Does anybody know where to download the images for the Osilloscope?thanks in advance,Huu

author: squadchannel
author_rank: Frequent Contributor
timestamp: September 30, 2024, 02:29:37 pm
content: the restore disk is available in xdevs. wait a moment and we will upload it to mega.

author: squadchannel
author_rank: Frequent Contributor
timestamp: September 30, 2024, 03:12:29 pm
content: restore #1:https://mega.nz/file/nHwWQKDS#xR0YMKE7zGxOKUgO-k1sPMQ1Qiusgc3DeufFM8SRa6Irestore #2:https://mega.nz/file/jbACFRKb#qwwb75klGsXfj3skkhZxxP8x0_WnvBT2eLm5seGKkOArestore #3:https://mega.nz/file/aThSnKLY#_ubm3lBGWR1OgC1LUKk9ygjKUSe_TGs0Dmi-Squfw9Moption software:https://mega.nz/file/aHJhgRQS#Ol1OUxtE5tPx9vbLwexJZItd2vRtjsOPR8VZ_nsyzaUIf you download it, please reply. after I will then remove the mega link.MOD:deleted

author: HuuPhuc
author_rank: Newbie
timestamp: October 02, 2024, 04:15:00 pm
content: Thank you! I've downloaded the files.What program do I use to join the ISO files?

author: coromonadalix
author_rank: Super Contributor
timestamp: October 02, 2024, 05:10:15 pm
content: you don't join themultra iso power iso ... if the iso is bootable or not ... theses are bootable, and have powerquest software in them to do the recovery process

author: HuuPhuc
author_rank: Newbie
timestamp: October 04, 2024, 06:59:38 pm
content: I was able to burn the ISO files onto the CDs. However, when I ran the recovery disk1 the message on screen said "BF86510A Motherboard Required!" , contact Tektronix technical support for assistance.Any suggestion would be much appreciated.Thanks in advance,

author: coromonadalix
author_rank: Super Contributor
timestamp: October 04, 2024, 11:47:32 pm
content: means you'll be forced to do an os install regardless of the motherboard, and find in the cd's all the needed drivers etc ... to do all manuallyand check any error in the device manager and aswer theminstall intel INF drivers 1st and do all others afterwardseven having an ghost image would mean some problems if it was done on another mobo type in the scope ... but it could or would boot since they are intel based ...
TDS5052 Loss of calibration data - Page 1
Forum section: electronics / repair

author: zhang3166a
author_rank: Newbie
timestamp: April 19, 2023, 04:05:13 pm
content: I have a TDS5052 non-B oscilloscope, and the display is as shown in the figure when it is turned on. Has anyone encountered it?Is there any way to solve it? It used to be perfect. Recently, this prompt appeared when I turned on the computer.

author: calibrationfixture
author_rank: Regular Contributor
timestamp: April 21, 2023, 06:07:47 am
content: Hi,Yes, I have encountered the same display:https://www.eevblog.com/forum/repair/tds5104-cant-find-cal-data-during-starting-scope-application/msg4624741/#msg4624741Succes,Calibrationfixture
TDS5054 SPC error 50ohmOvld - Page 1
Forum section: electronics / repair

author: Deepblue
author_rank: Contributor
timestamp: October 11, 2020, 08:34:06 am
content: Hi all,I hope someone can help me locating this issue.I have a Tek TDS5054 (not B-model) which has been working just fine, but suddenly I get a SPC error and when doing diagnostics, it reports a 50ohmOvld error. I would suspect the 50 Ohm termination resistor to be defective, but how do I locate this, and is it possible to diagnose which channel is at fault?I get no detailed info when doing the diagnostic test.

author: Jwalling
author_rank: Unknown
timestamp: October 11, 2020, 04:46:14 pm
content: https://www.eevblog.com/forum/testgear/$200-reward-for-information-regarding-tek-tds5000b-debug/Post the debug log.
TDS5054B-NV signal traces - Page 1
Forum section: electronics / repair

author: uccoskun
author_rank: Newbie
timestamp: November 26, 2021, 12:52:34 am
content: Hello All:I have a TDS5054B-NV oscilloscope. It passes all tests (instrument diagnostic and SPC tests). However, I cannot get any trace on the screen. When I turn on channels, I do not get even noise, only trigger tick and ground-level tick. Do I miss anything?Here is the history of the oscilloscope. I bought it from eBay. It was working OK but slow. I decided to upgrade it with a new SSD hard drive, faster CPU, motherboard, and XP. Now the software works crazy fast but no trace. Initially, the tectronix gave an error like it can not communicate with the front, but now it does not show that error. Tektronix software runs fine. I remember somebody mentioned display color resolution. I tried both 16bit and 24bit color in the display setting. It still did not help.When I upgrade the power supply, the original power supply has a special 10pin connector. Two of the pins are used to trigger on the line signal. Three of the pins, I'm not sure what it is, so I just ignored them. This is the only thing I did not do right. I hope it is not something that powers some relays or chips.I have the original hard disk and motherboard. Now, the software stacks at the Tektronix welcome page.Would you please let me know if you have any idea?Thank you,Ulas
TDS520A  CRT - Page 1
Forum section: electronics / repair

author: dgimb
author_rank: Newbie
timestamp: July 28, 2025, 01:49:31 pm
content: Hi everyone,I’d like to share the story of repairing my Tektronix TDS520A oscilloscope.Maybe someone will find it interesting or helpful.The ProblemAfter about2.5hours of normal operation, the display would stretch, dim, and then go completely blank.The power supply would start cycling into protection mode.To reproduce the issue, the oscilloscope had to be fully assembled so that the internal temperature could rise — only then would the problem appear consistently.Also, in order to remove the CRT control board, it was necessary to completely remove the CRT tube — a bulky and time-consuming process.During the investigation, I discovered that the CRT board was actually from a TDS520B, not a TDS520A-------- Repair – Round 1 ------Since the brightness was fading before failure, the first suspect was the high-voltage rectifier diode inside the HV transformer.I bought some high-voltage diodes and connected them in series with the CRT anode line (CRT_ANODE).Some electrolytic capacitors were also replaced.Result:negative.-------- Repair – Round 2 ------I connected to some test points on the board to take measurements and check the waveforms.Measurements revealed unstable voltage and current(when issue appeared, floating range 10-20V) after theLM317(U438) voltage regulator.I replaced theLM317(U438) with a new one.Result:still negative.-------- Repair – Round 3 ------I replaced the following ICs:TDA1170S(U428)MC1391P(U415)After that, a new issue appeared: vertical sync instability.To fix this, I replaced resistorR529with a variable resistor to allow fine-tuning of vertical sync.Result:still negative.-------- Repair – Round 4 ------Replaced components:Transistors: Q205, Q405Diode: CR205Capacitors: C507, C427Result:Positive – the issue is resolved!I can’t say with 100% certainty which component was at fault,but my main suspect is the non-polarized electrolytic capacitorC427(1uF).This capacitor is involved in pulse shaping for the switching transistorQ205.My theory is that it caused wrong (too long) pulses to be generated on the primary coil of the HV transformer,which eventually overloaded the power supply circuit and triggered protection.These are parts(also ICs: TDA1170S (U428) and MC1391P (U415)) that were replaced:Let me know if you have questions or need schematics – I’d be happy to help!
TDS540 intermittent test failures - Page 1
Forum section: electronics / repair

author: StefanS
author_rank: Newbie
timestamp: September 29, 2021, 12:11:39 am
content: Hi All,I've just finished recapping my TDS540 (from either 91 or 92) and it continues to show two failures on startup:FAIL ++ Acq/Proc InterfaceFAIL ++ AcquisitionThe odd thing is, if I run the diagnostics immediately afterwards, the unit passes. Also, on a RARE occasion, it will pass on startup. Error log only shows a previous SRAM problem at 0x7300000, which was corrected by cleaning U101.Any thoughts?Thanks,Stefan

author: CaptDon
author_rank: Super Contributor
timestamp: October 01, 2021, 02:24:11 am
content: What is the condition of the battery backed ram which stores the cal data as well asthe real time clock? Sounds like the signal chain is not actually failed but the data isgetting corrupted when the unit is powered down. Very common problem as the Dallaschips internal batteries are failing. NOTE....All dallas 1650Y and 1250Y i.c.'s on Ebayare bad, dead or fake. Seek out the guy selling the hybrid modules with the batteryon top. The restore data is readily available on this site.

author: StefanS
author_rank: Newbie
timestamp: October 01, 2021, 03:07:22 am
content: Thanks, Capt’n. The battery is probably original, but seems to be holding date & time. Additionally, the memory errors are reappearing when the unit fails. The intermittent nature of this is the worst.
TDS540 newbie owner - experience so far - Page 1
Forum section: electronics / repair

author: rjmusto
author_rank: Contributor
timestamp: March 05, 2022, 07:50:22 pm
content: Have recently acquired one of these scopes, first time for me tackling a Tektronix example. Sold as faulty with the ubiquitous acquisition faults showing at startup.In good overall condition and very little sign of corrosion evident on the two main boards.Checking the electrolytics in situ showed only 9 dud, but some others have a signs of leakage, so am working on replacing these ones first. The processor board looks clean though with no shadows around these ones. But maybe I’m being overly optimistic……Why did Tektronix decide to specialise their probes with select pins? This one came with none (no surprise) so will probably have to try and get hold of some. But why not just make the scale factor selectable in the menu?One immediately obvious issue though is the noise from the fan. OMG - were they really shipped like this? If so, don’t think I’ll be able to live with it for long. Has anyone found a newer, quieter alternative I wonder?Good to see active support still there for this old bit of tech though! Hope I succeed in getting it going…..Ralph

author: wn1fju
author_rank: Frequent Contributor
timestamp: March 05, 2022, 11:15:35 pm
content: Do yourself a favor and replace ALL the SMT electrolytics. Doing anything less is just asking for eventual trouble. On my similar TDS520, there were many capacitors that either 1) looked like there was no leakage, but tested bad when I pulled them, or 2) looked like there was no leakage, but there were small puddles right underneath the capacitor that weren't visible until I pulled them.And of course, scrub clean the boards, and clean them again, and clean them again. Look carefully with a magnifying glass for broken/corroded traces and/or IC pins in any area where there was leaking electrolyte.Yes, the fan is a bit loud, but it doesn't bother me.

author: rjmusto
author_rank: Contributor
timestamp: March 06, 2022, 01:11:21 pm
content: Hi, thanks for the replyTook your advice and removed some caps that looked ok and, sure enough, clear signs of corrosion underneath. So will just have to knuckle down and work my way through the whole lot….
TDS540 spc fail error 2260 - Page 1
Forum section: electronics / repair

author: Dmoff
author_rank: Newbie
timestamp: March 15, 2022, 12:44:26 pm
content: Good morning, ive got a tektronix TDS 540 that fails signal path compensation Error 2260 Repet cal failed. when testing all channels it passes everything to spec. is there something i should be looking for that i wouldnt see otherwise. is it a nvram on acq board problem. its operating perfect to my knowledge other than that spc failure. Thank you in advance.

author: TERRA Operative
author_rank: Super Contributor
timestamp: March 15, 2022, 01:26:26 pm
content: Is the fault specific to one channel?If so, you can try swapping the input hybrids between channels to see if the fault follows. If so, you might be due for a new set of relays. It's one of the most common causes for SPC failures.

author: Dmoff
author_rank: Newbie
timestamp: March 15, 2022, 02:08:18 pm
content: it dont believe it is. all 4 channels are reading in spec. i messed with all 4 channels switching vertical scale to activate relays for about 3-4 minutes per channel. besides that spc fail im not seeing any out of tolerance reading or indications its effecting those 4 channels.

author: shakalnokturn
author_rank: Super Contributor
timestamp: March 16, 2022, 01:38:27 pm
content: If all channels seem to make sense both for amplitude and frequency on all timebase settings and input sensitivities with an external source, I'd look towards the internal signal used as calibration reference.If the acquisition isn't reading back the expected values due to a reference signal out of range the scope should throw an error.Of course knowing the model the first thing to look for is SMD capacitor electrolyte leakage.

author: TERRA Operative
author_rank: Super Contributor
timestamp: March 17, 2022, 08:34:20 am
content: Yeah, as shakalnokturn mentioned, if the fault is common to all channels, I'd be looking at the internal signal generator for problems, after doing the leaky capacitor dance.Also, I'm not 100% sure, but if the 500 series is similar to the 600 series in that all channels end in a single acquisition chip (rather than one per channel as in the 700 series) that's another potential point of failure that could affect all channels.Easiest next step after doing the capacitor thing is to grab the schematics and poke at the internal signal generator. You might even have a corroded trace or two, it's not uncommon with these leaky capacitors.

author: shakalnokturn
author_rank: Super Contributor
timestamp: March 17, 2022, 09:09:02 pm
content: Quote from: TERRA Operative on March 17, 2022, 08:34:20 amNo, the 500 series are not CCD based and don't share the common FISO ASIC as on the 600 series.
TDS540 spike problem on all channels - Page 1
Forum section: electronics / repair

author: mwbarth36
author_rank: Regular Contributor
timestamp: January 26, 2022, 03:03:11 am
content: I have been fighting a strange problem with a TDS540 that I recently purchased. All four channels display a signal, but there is a spike running randomly through the waveform. I am aware that this is usually a memory problem if it occurs on a given channel. In my case, however, the spike is present at the same location on all four channels. The three photos I have attached show this. Also note that the spike is always in a direction toward the base line (0 Volts). If the trace is moved to zero volts, the spike is not present. As far as I can tell this is not likely to be a memory problem as the memory is separate for each channel. As can be seen from the photos of channel 1 and 4, the spike is displayed in exactly the same place on the trace. If I had displayed channels 2 and 3, there would have been a spike at the same location, always in a direction toward 0 Volts.I know the problem is with the Acq board A10, as I have tried with several known good Main boards (A11), and the spike is still there. The fact that it is always in the direction of 0 Volts, and that gets more pronounced the further the trace is moved from the base line should give a clue as to the possible problem areas, but I cannot seem to come up with an answer.Can anyone help, please! All comments will be appreciated.

author: mwbarth36
author_rank: Regular Contributor
timestamp: January 26, 2022, 03:11:57 am
content: Here is the third photo.

author: CaptDon
author_rank: Super Contributor
timestamp: January 27, 2022, 06:41:06 pm
content: I had a similar problem on a TDS540 in the lab. Electrolytic leakage and corrosion on the acquisition board. Had to replace those bad SMD electrolytics but most importantly clean the board with hot soapy water and a very soft brush then rinse thoroughly with hot clear clean water then used a hair dryer to drive all moisture off the board. Had to clean it and dry it Twice to fully resolve the issue!!

author: mwbarth36
author_rank: Regular Contributor
timestamp: February 02, 2022, 02:27:02 am
content: Just to put the finishing touch on this Thread, I did find the problem and now have a very nice scope. The problem was with the small, solder in, pc board acting as the filter for the phase lock loop. The two 33ufd caps had been replaced, but had damaged some of the lands and connections on the board. I replaced the board, and the scope no longer has the 'spikes', in fact, it works fine and passes all tests. Thanks for your suggestion, the problem did turn out to be related to the leakage of one of the capacitors.
TDS5/6/7xx Tristar DSP Instruction set - help? - Page 1
Forum section: electronics / repair

author: lucienmp
author_rank: Newbie
timestamp: June 25, 2019, 12:58:02 am
content: Hi folks,The heart of the TDS5/6/7xx graphics rendering from the AQU board is the Tristar DSP.Does anyone have any technical details, the compiler, instruction set manual, or anything on this guy ?Of course there is the excellent TDS520D Components manual that tells me where it is, roughly what it does and its pinout.But I would like to know more about the internal operation and instruction set that the VxWorks loads instructions into it.Cheers,Luc
TDS6124C PowerPC board FPGA bitsream corrupted - Page 1
Forum section: electronics / repair

author: ab1033
author_rank: Newbie
timestamp: December 14, 2021, 06:06:22 am
content: Hello everybody,I found the problem on my TDS6124C.The bitstream of the Spartan2 FPGA consists essentially of ones.Does anybody have an idea where I could get it?I'll ask Tektronix, but I expect that in best case they can onlyreplace the board nowadays.

author: ab1033
author_rank: Newbie
timestamp: December 17, 2021, 09:41:04 pm
content: I found that very likely it is the same PPC board as in the TDS7154B, and TDS6154C.Does anybody have access to such a unit?
TDS684A Display problem - Page 1
Forum section: electronics / repair

author: mwbarth36
author_rank: Regular Contributor
timestamp: October 28, 2021, 07:16:50 pm
content: I recently purchased a TDS684A scope with a problem in that the display will not adjust to the full width of the screen. When originally purchased, both the vertical and Horizontal were compressed, although the horizontal much more than the vertical. See the first attachment. I was able to get the vertical back at the proper scale using the vertical size control, although now it is at the extreme end of it's range. The thing I find strange is the display is focused, has sufficient brightness, and the linearity is good, it is simply compressed in the horizontal direction. I have checked the 21 Volt supply generated on the video driver board and it is a solid 21 Volts.One of the reasons I like working on the TDS series of scopes is that one can operate the scope and have access to all circuits on the A10 and A11 boards, making service of these boards relatively easy. Not so with the video boards! They are not possible to access when the scope is assembled. I suspect the problem would not be difficult to identify if one could scope the signals in the horizontal circuitry, but there is not hope of doing that. I thought maybe someone has had this problem with a scope in the TDS series and could provide some insight into what the bad component is likely to be.Any suggestions or comments will be greatly appreciated!

author: mwbarth36
author_rank: Regular Contributor
timestamp: November 07, 2021, 02:08:14 am
content: Anybody with a clue?? Thought sure I would find someone with this problem.

author: james_s
author_rank: Super Contributor
timestamp: November 07, 2021, 03:09:41 am
content: If the vertical adjustment is all the way to the extreme then obviously the vertical axis is not fixed either, you are compensating for a fault. Is it possible that the EHT is too high? The picture actually shrinks as the voltage gets higher.
TDS694C doesn't boot when acquisition is powered - Page 1
Forum section: electronics / repair

author: SuperSVGA
author_rank: Contributor
timestamp: May 06, 2022, 12:49:20 pm
content: I have a TDS694 which only starts up when either the +25V (3.3V) to the acquisition board is disconnected, or the data bus for the acquisition board is disconnected.Here's the brief history I have with this scope.When I first powered it up, it started up fine and reported Acquisition as failed.I tried to trigger on the probe compensation signal, but it didn't look like triggering was working.I left it running for a few minutes and looked away, and when I looked back the display was off. It was still running though, I could turn channels on and off and heard the relays click.At that point I thought I might have heard an angry hissing, so I quickly unplugged it and began tearing it apart.I did a lot of searching of the low voltage power supply and display boards, but the only thing I found appeared to the electrolytic capacitor on the CRT neck board, which either was burnt or dirty, and may have had a hole in it, but I'm not certain. It still seemed to test alright, but I replaced it anyway.I also dumped the Dallas DS1250Y and socketed it.After putting everything back together, it powers up but doesn't go through the normal boot sequence. Garbage flashes on the screen briefly as it does normally, but then some relays click and all the front panel lights go off.Eventually I discovered that if I disconnect the +25V cable going to the acquisition board, it fully boots up and somehow all the tests pass. But no waveforms are displayed at all.That +25V line labeled "J124" is unhelpfully referred to as "TDS 694C" in the service manual. From what I can tell it's only for powering the DC converter that generates 3.3V.I've taken the 3.3V converter out and tested it, but couldn't find any problems there. I also tried directly powering it with 25V from a bench supply, but it made no difference.The other odd thing is, with the +25V connected but the D1 Bus disconnected, the scope starts up, with several tests failing.Any ideas what might be wrong? I'm not sure the unit I have is a regular production unit either...

author: m k
author_rank: Super Contributor
timestamp: May 18, 2022, 03:14:56 pm
content: If you heard hissing the electrolytic must have been a bit bigger.They can also be quite a failure ninjas.Have you tried external and current limited 3.3V supply?

author: SuperSVGA
author_rank: Contributor
timestamp: September 28, 2022, 06:58:19 pm
content: Quote from: m k on May 18, 2022, 03:14:56 pmI'll have to try that next time I have room to crack it open. Hopefully it doesn't need the full current of the converter, I think it was rated at 10A but the most I can supply with the bench supply is probably around 6A.If that doesn't work I'll probably just have to make myself crazy by spending hours probing at the board. Something is signaling to the system to shut off when that 3.3v is supplied, and that signal must go through the D1 bus somehow.This thing is just a massive pain to take out and put in repeatedly. I hope I don't have to get to the analog boards again...
TDS6XX / 7XX waveform help needed, - Page 1
Forum section: electronics / repair

author: CaptDon
author_rank: Super Contributor
timestamp: May 16, 2020, 12:57:44 pm
content: Is there a way to change the sample rate for the slower sweep speeds?My TDS644B is great for looking at USB rise times and so forth but I haverun into a snag at slow sweep speeds as follows,I have a 1mhz RF sinewave that is AM modulated by 1khz. As we all knowthat waveform should look like a bunch of ovals standing on their endsand then their sides touching each other. When I slow the sweep downto maybe 200us or even slower the 1mhz gets aliased to uselessness!!!I can get a perfect expected display on my older SC502 analog scope butcan't get anything useful on my TDS644B or even my TDS2004B for thatmatter. Have any of you found a way to display such a waveform on anolder digital scope?? Thanks!!

author: wn1fju
author_rank: Frequent Contributor
timestamp: May 16, 2020, 03:04:39 pm
content: At least on my TDS520, which should be similar, you can put the acquisition mode into Peak Detect (Envelope might also work OK). You can also adjust the holdoff in the trigger menu. That should get you a stable display like it would look on an analog scope.
TDS7000B series  power button not working - Page 1
Forum section: electronics / repair

author: charlyd
author_rank: Frequent Contributor
timestamp: July 01, 2022, 08:01:21 pm
content: Hi a while ago i bought a damaged TDS7000B series scope.and the power button doesn t respond to any press on it.no power on.but when i open up the unit and press the power button on the PPC board the unit starts up.i followed the connecting from the PC board power button line it leads to the PPC board and from the flat cable connector next to it leads me to the controller board behind the lcd display.i can trace the 2 wires until the controller. (see attachment)on the controller multi layer?? i get confused and looser track.i guess there lays my problem.anybody experienced with this type of controller board 679-5497-00. or had this problem? these boards are expensive so should be repairable..i guessbtw my green flex pcb is in great condition, like New.

author: tonyh88
author_rank: Regular Contributor
timestamp: July 04, 2022, 02:19:01 am
content: Hey,I'm not sure I understand the tracing of the power button signal you tried to explain.Photos would be nice and I'm sure you would get more help if you provide a bit more visual information.You mean you traced the power button signal up to J2 on the controller board?The controller board you showed in the attachment seems simple enough with very few components so it should be possible to trace the power button lines with a multimeter
TDS7000B series poweron button & power led unresponsive - Page 1
Forum section: electronics / repair

author: charlyd
author_rank: Frequent Contributor
timestamp: June 12, 2022, 07:49:36 am
content: Hi i bought damaged TDS7000B series scope a while ago something went throught the display and touchpanel. so both Total destroyed. after replacement i found put that the poweron button & poweron led located on the green foil-PCB in the lowerleft corner gave no response. i could poweron with inside button but not very handy of course.i tried to trace the power switch & led lines from PCmotherboard to button and so with the led. the cabling starts on the pc motherboard with a 8 pin Grey connector afterwards it is connected to the black chassis part ( like a comport) on the powerpc. next to that connector on the far end on the powerpc board on the fanwall site are two small black flatcable chassisparts (about 4cm and 2,5cm) .from there on 2 links from the switch and 2 from the led go to the display interconnect pcb. i would guess that they were easy to follow over that interconnect board to the foil-pcb connector, but no.complete lost out there.is there somebody who had a similar problem or a spare display interconnect pcd laying arround for test purpose. with the part number: 679-5497-c0 or 679-5497-00any help or tips are welkome to solve this "simple" problem.is there something i over looked?the new touch panel and new display connected to this interconnect pcb are both working ok and buy a new interconnect pcb which is later not the problem feels very weird...
TDS7154B booting  - Page 1
Forum section: electronics / repair

author: hitecelec
author_rank: Regular Contributor
timestamp: April 25, 2019, 09:05:52 am
content: hi AllI have a TDS7154B that is defective. Windows boots up ok but later on application hangs updisplay "Tektronix digital Phosphor Oscilloscope powered by DPX technology with pin point troggering"Any clues as to how do i proceed with the troubleshootingRegardsAnand

author: hitecelec
author_rank: Regular Contributor
timestamp: April 25, 2019, 09:46:55 am
content: Hi Allthe application did boot up after some time and diplaysAcq board HF step Phase cal error code 351.Running SPC does not help and it failsRegardsAnand

author: BG1TZA
author_rank: Newbie
timestamp: April 26, 2019, 08:46:16 pm
content: Check if the driver is correct
TDS744A Color Display Flicker - Page 1
Forum section: electronics / repair

author: k1mgy
author_rank: Regular Contributor
timestamp: December 05, 2019, 02:28:48 pm
content: My TDS744A, which has already been re-capped (to include all caps in the display driver) is exhibiting a symptom a few minutes after power on (heating) where the colour display flickers. Best shown by video:https://drive.google.com/open?id=1pX_4fu-fTLoiURP0z4U-7bewY4jmLD4uService manual mentions shutter board, but have no idea where that board is.Any ideas?

author: Jwalling
author_rank: Unknown
timestamp: December 05, 2019, 02:59:28 pm
content: Shutter board is on the HV board which drives the CRT.I have lots of them - if you're in the USA I'll send one to you for cost of postage.

author: k1mgy
author_rank: Regular Contributor
timestamp: December 05, 2019, 03:20:47 pm
content: Thank you Jay.I just sent you a message (pm)./mark

author: k1mgy
author_rank: Regular Contributor
timestamp: December 08, 2019, 09:15:12 pm
content: Found and resolved the problem with the TDS744A.First, many thanks to Jay, who generously provided a replacement shutter board. Turns out, that was not the issue.In, "TDS Color CRT Driver Repair (700 series): all by sniffing" (https://wonghoi.humgar.com/blog/2018/11/03/tds-color-crt-driver-repair-700-series/) I found this:QuoteSo I removed the entire CRT assembly. There was a layer of dust on the component side. A few bits of contamination on the underside. Flushed it with warm water, then cleaned the bottom with flux cleaner, then used anhydrous isopropyl to wash everything off, and then thoroughly dried.Voila! No more shutter issue.

author: george.b
author_rank: Frequent Contributor
timestamp: December 08, 2019, 09:50:46 pm
content: So there was a leaked electrolytic capacitor?

author: k1mgy
author_rank: Regular Contributor
timestamp: December 09, 2019, 12:31:35 am
content: Didn't see evidence of that. And last year when I tackled this same unit, I re-capped the entire scope.However, there was a coating of dusty crap on top, and some spots on the bottom side where flux and other residue were present.

author: george.b
author_rank: Frequent Contributor
timestamp: December 09, 2019, 07:00:57 am
content: Ah, right. It's just that the excerpt you quoted there mentioned a smell of electrolyte, that threw me off for a bit there.So, congratulations on the repair! Washing stuff is the ticket sometimes, I know I've repaired a couple of wonky boards by washing before.

author: Jwalling
author_rank: Unknown
timestamp: December 09, 2019, 10:59:42 am
content: Quote from: k1mgy on December 09, 2019, 12:31:35 amGlad to hear you've sorted things out! But I wonder if the real issue is that there was some cap goo somewhere that your cleaning removed...Sometimes it collects just under the cap itself and conducts between the two pads. This is fairly common on the power supply. After some time it starts burning a hole in the PCB.I've seen this on the HV board as well. It can get pretty bad if left unchecked!
TDS744A. How to clear error log? - Page 1
Forum section: electronics / repair

author: eurgenca
author_rank: Regular Contributor
timestamp: April 21, 2020, 09:01:15 am
content: Hello.I have TDS744A oscilloscope and has huge error log. So I like to clear error log to see wich error will remain but is it possible to clear this log without GPIB, because I dont have GPIB controller or card.Regards, Sebastijan.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: April 22, 2020, 12:52:29 am
content: no

author: james_s
author_rank: Super Contributor
timestamp: April 22, 2020, 06:46:35 am
content: You can build a GPIB interface for not much more than the price of a beer.https://www.eevblog.com/forum/projects/ar488-arduino-based-gpib-adapter/
TDS744A power supply bad - Page 1
Forum section: electronics / repair

author: misu1lica
author_rank: Newbie
timestamp: March 24, 2021, 07:08:36 am
content: Hi, I have a faulty TDS744A oscilloscope.The power supply is damaged. A similar scheme for the power supply is TDS520B.The defect is: the Cu path on the -15Vdc power board burned the board and I completed it.Better said: the route between "-" C94 and CR27 burned the board.I checked Q5, Q6, Q7, Q8, R1, R2, R3, R8, R9, R10 and they look fine.I checked CR27 is fine.When I supply the source with voltage, I press the Start button and the source wants to start, the relay is heard to switch on and off immediately.The power supply board is open and I have no consumers on it.I think the + 15V BIAS voltage is fine, because the relay sounds to be working. I assume that the + 12V BIAS voltage is also OK.Does anyone have an idea how to solve the problem?RegardsMihai C