hybridfree/eevblog-posts huggingface dataset:
Tek SG5030 E350 error - Page 1
Forum section: electronics / repair

author: syau
author_rank: Frequent Contributor
timestamp: June 23, 2020, 11:43:56 pm
content: Scored a SG3050 with level head, it will throw a E350 error after output enable for a few seconds. Googled and found not much information in repairing this unit.Will tear it apart and see if any obvious things happened.

author: picburner
author_rank: Frequent Contributor
timestamp: June 24, 2020, 10:58:33 am
content: You can find somethinghere.There is also the manual with the schematics.

author: picburner
author_rank: Frequent Contributor
timestamp: June 24, 2020, 11:13:03 am
content: and this is the answer of the manual regarding the E350 error:

author: syau
author_rank: Frequent Contributor
timestamp: June 24, 2020, 03:24:03 pm
content: Open up the unit, smell fishy and all SMD capacitor leakingAlso, this type of PCB is my most dislike one as the pad tend to come off very easy

author: syau
author_rank: Frequent Contributor
timestamp: June 24, 2020, 03:25:45 pm
content: Quote from: picburner on June 24, 2020, 11:13:03 amNot much usable troubleshooting information / flow chart. But lucky schematic provided

author: texaspyro
author_rank: Super Contributor
timestamp: June 25, 2020, 06:30:33 am
content: Most levelng head problems that I have seen are due to contact issues with the relays. The relays consist of a top part (head) that is screwed to the PCB. It includes the magnets and a leaf spring contact on a pivot. The contacts touch pads on the PCB. Remove the relay heads, inspect and clean (VERY carefully) the leaf springs, and clean the PCB pads.

author: wizard69
author_rank: Super Contributor
timestamp: June 25, 2020, 07:20:25 am
content: Best of luck with this unit. It is obvious that a complete recap is needed. Hopefully you will have a running unit. I love this old Tektronix hardware, it is too bad they gave up on it.Quote from: syau on June 24, 2020, 03:25:45 pm

author: syau
author_rank: Frequent Contributor
timestamp: June 25, 2020, 08:03:03 am
content: Quote from: wizard69 on June 25, 2020, 07:20:25 amAll SMD cap leaking with corrosion aroundBesides cap, ordered some resistor, capacitor, op amp. Spend whole day cleaning up the board with IPA.

author: syau
author_rank: Frequent Contributor
timestamp: July 06, 2020, 10:06:20 am
content: Received batch of Vishay Dale (VA) CRCW1206 1% resistor from Digi-key to replace those damaged by the leaking SMD capacitor and found they didn’t have value printed on top ofWish me luck
Tek T953A unstable triggering - Page 1
Forum section: electronics / repair

author: Axtman
author_rank: Regular Contributor
timestamp: July 18, 2023, 10:22:24 pm
content: I recently picked up a Tektronix 935A 35MHz dual channel oscilloscope for cheap. It is clean and everything appears to be in good working order. The only issue is I cannot get the test input signal to stay put. It keeps wandering horizontally. I know that Tek scope are noted for their stable triggering. Any help would be appreciated. Thanks.
TEK TDS 3052 Screen has blotches. - Page 1
Forum section: electronics / repair

author: rcard53762
author_rank: Newbie
timestamp: July 16, 2025, 11:36:46 am
content: MY TEK TDS 3052 Screen has blotches in the screen.I got a replacement screen from another TDS with a good screen and the blotches are still there.So now I think it has to be the video controller or maybe the video RAM.Has anyone run into this problem?If so what was your solution?Thanks
Tek TDS 3054B main board schematics anyone? - Page 1
Forum section: electronics / repair

author: spark058
author_rank: Newbie
timestamp: April 22, 2020, 07:56:35 pm
content: Hi all. I have a Tektronix TDS 3054B portable scope that has problem. It shows up as a trigger glitch on all 4 channels when I tap on the case. I have found the output voltages of a couple regulators go briefly unstable when I tap the case so I assume that is root cause of the trigger behavior. Anyone have experience with this model or access to schematics that would be a great help. Thanks!!
TEK TDS 420A firmware help. - Page 1
Forum section: electronics / repair

author: eurgenca
author_rank: Regular Contributor
timestamp: September 16, 2021, 06:21:11 pm
content: Hello.I bought tek TDS420A with all LED on.I was thinking it'll easy repair but...At first startup I smell caps. In PS i found 1 bad cap and replaced it. I check all other and looks O.K.So PS running and all voltages are good.Then I check 27K smd resistor on CPU board for reset and it is o.k.On led diplay on cpu board it stops at "-" so cpu clearly running.It is time to build console adapter and here is the problem:Bootrom Header Checksum passed.Bootrom Total Checksum passed.BootRom Check Sum passed.Bus Error Timeout test passed.Bus Error Write to Bootrom passed.GPIB Test passed.Kernel Diagnostics Complete.Calling SDM (monitor) Routine.SDM (monitor) not enabled.Enabling Bus Control register. Value = 0x2Flashrom Programming Voltage is OFF.Flashrom DSACK and JumpCode test passed.Invalid Flashrom Body checksum = 0x9115, should be 0x9105Flashrom Checksum test failed.Cannot transfer control to Flashrom.Transferring control to the SDM (monitor).Can someone help with this.I suppose firmware is corrupted, but I can't find firmware on google.So if someone have firmware files and tell me how to flash this scope I'll be very glad.Sebastijan.

author: eurgenca
author_rank: Regular Contributor
timestamp: September 18, 2021, 09:02:28 am
content: Hello.Can someone please provide me a copy of firmware for TDS420A.Regards, Sebastijan.

author: madao
author_rank: Frequent Contributor
timestamp: September 18, 2021, 02:34:03 pm
content: i have Firmware from TDS430A , it would work with your TDS420A..But, i am not in house.Pleas be patient.Greetingsmatt

author: eurgenca
author_rank: Regular Contributor
timestamp: September 18, 2021, 03:06:54 pm
content: Hi Matt.Thanks for help. I am glad that you willing to share FW.No hurry I need to buy adapter first.

author: madao
author_rank: Frequent Contributor
timestamp: September 19, 2021, 04:51:54 pm
content: here

author: eurgenca
author_rank: Regular Contributor
timestamp: September 20, 2021, 05:33:24 am
content: Thanks Matt.Today I'll buy gpib adapter from max-bit and then will see...Thanks again, Sebastijan.

author: eurgenca
author_rank: Regular Contributor
timestamp: October 03, 2021, 06:13:27 pm
content: O.k. I received usb gpib cable and install ni software.Connect TDS on PC and first made backup file.When I was compare my file with Matt's file was significant change. So I made next step, cleaning flash.When confirming done I flash new file and ta daaa. works.Now I must enable options and make some testing but for today I am done.Thanks, Mat for help.
Tek TDS 540 (no suffix) Power Supply issue - Page 1
Forum section: electronics / repair

author: Marco_Mar
author_rank: Contributor
timestamp: April 07, 2024, 12:43:28 pm
content: Hi,I bought a completely dead Tek TDS 540 (no suffix).When plugged, it tripped the RCD, due to a leaky CY cap.After replacement, no more RCD tripping, but the scope won't start.Following service manual troubleshooting hints, I'm testing the power supply (119-3371-03) with no load.The attached pic shows what I see across C12: don't be fooled by the Fluke readouts: the voltage is downscaled 100-1.The average voltage is correct (around 410 V) ma where are those tremendous spikes (200 Vpp) coming from?I'm stuck: please any help will be highly appreciated.Thank youMarco

author: TERRA Operative
author_rank: Super Contributor
timestamp: April 07, 2024, 04:01:23 pm
content: First up, replace C17 with a new Low-ESR capacitor (yes, it does need replacement!47uF and voltage rating greater than 80V) and check the associated parts as per the image in this post:https://www.eevblog.com/forum/repair/tektronix-tds500-tds700-power-supply-models-psu-repair/msg5165748/#msg5165748

author: Marco_Mar
author_rank: Contributor
timestamp: April 07, 2024, 07:54:37 pm
content: Hi Terra,thank you for answering me.I followed your recommendations replacing the other 3 RIFAs (C4 was already replaced) and C17.No change: spikes again.How could I check VR5 and VR4 (TVS Diodes)?Attached, is a screenshot of +15V BIAS from STANDBY SUPPLY.The average voltage is ok, apart from the same spikes as for + BULK.Thank you

author: TERRA Operative
author_rank: Super Contributor
timestamp: April 07, 2024, 11:39:01 pm
content: Ok, preventative maintenance is done.To check the TVS diodes, they would need to be pulled and tested to their working voltages on a current limited power supply similar to how you'd test a zener. i.e. don't worry too much about it. They protect the transistor highlighted in the linked image, and if that was dead due to dead TVS diodes, you would get no life in the PSU at all.Besides the voltage spikes you are seeing, what are the symptoms shown by the PSU? Is it not starting up? Bad output voltage? etc?

author: Marco_Mar
author_rank: Contributor
timestamp: April 08, 2024, 11:34:00 am
content: Hi,well, when I power on the scope with the front panel button I can hear a click inside but nothing else happens.I pulled out the PS and checked the outputs: nothing besides spikes!I noticed that U5 (PWM) on A18 is permanently switched on and off (pin 10) at the same rate as, guess what!, the spikes...Many thanks

author: TERRA Operative
author_rank: Super Contributor
timestamp: April 08, 2024, 02:52:34 pm
content: Ok, so it seems your standby power is operating (hence the click).I would start by checking the transistors in the main converter and boost converter sections (in the schematic page you posted above), I've had bad transistors there before.It almost looks like the PSU is trying to start over and over but is hitting some sort of self-protection each time.
Tek TDS 540a backup with Tektool Madao - Page 1
Forum section: electronics / repair

author: lucatz
author_rank: Contributor
timestamp: November 26, 2020, 08:17:33 pm
content: I have a TDS540a which is rather old as you all know. I was worried about the internal Dallas 1650 falling ie battery. So I used tektool (Thanks Madao!) from a thread I found here to backup firmware and nvsram. I wonder however if that actually has backed up Dallas chip? I don't think i would be in a position to calibrate this unit as I don't have all required equipment. And the Tek tool to actually perform the calibration. Read somewhere that it can also be done via GPIB but don't have any details on that. The Firmware backup is 3 meg and nvsram is 1meg. It detected chip 28F020Thank All

author: madao
author_rank: Frequent Contributor
timestamp: November 27, 2020, 08:05:28 pm
content: HelloI am glad :-)It is correct, TDS540A use 28F020 flash, 3 MB Firmware.NVSRAM on TDS5xxA is uniquie. Only this serie use DS1650 (512kb ) for calibration data, not DS1245 (128kb) by old serie and DS1486 (128kb include data & time) by new serie.But i haven't this serie, -> i don't know , which address have this 512kb NVSRAM-space. Probably address range 0x0400 0000 to 0x0407 FFFFCan i get this nvsram backup ? I want check. (or you should found 12345678 hexdezimal at 0x10 Address of NVSRAM Dump)Which GPIB Adapter did you use?

author: lucatz
author_rank: Contributor
timestamp: November 27, 2020, 08:47:49 pm
content: Yes I can send you mine. It does have 123456 as you stated but my backup is 1megI used fake Agilent82357Btks

author: madao
author_rank: Frequent Contributor
timestamp: November 27, 2020, 09:17:07 pm
content: It means, only lower 512kbyte is correct and NVSRAMdump is saved ! Other upper half is not important. But, you can write it direct with 1MB dump.Upper 512kb = dev /null ;-)(or -l 0x8000 instead -l 0x100000 by read/write-commando)
Tek TDS 540a - Page 1
Forum section: electronics / repair

author: lucatz
author_rank: Contributor
timestamp: October 27, 2020, 02:57:37 pm
content: Hi All,Looking for buttons around CRT for a used one I bought, mine is missing one button lower right. The Tek code is 214-4287-00 or 214-4287-01. Found some on ebay for a 100USD. If anyone has any other sources or parts lying around I would be willing to buy.Thank YouLuca

author: lucatz
author_rank: Contributor
timestamp: November 02, 2020, 06:41:14 pm
content: Hi All,Anyone ever try to make a slicon button with something like this...https://www.amazon.ca/dp/B07V5FFPWC/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B07V5FFPWC&pd_rd_w=yY0OT&pf_rd_p=970b3512-1bd2-4757-829e-ab114c5ecd76&pd_rd_wg=XwMvp&pf_rd_r=BB0T4GR71KKAHTEV79BM&pd_rd_r=032925f5-4603-4d29-b53c-b583e98c4266&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyQVlRMTFFVUhSQUNHJmVuY3J5cHRlZElkPUEwODI5OTAzMkhGREQ4WTBUSlZRVyZlbmNyeXB0ZWRBZElkPUEwMzE0MTQ4MzcwTzVGSjlDQjROUyZ3aWRnZXROYW1lPXNwX2RldGFpbCZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=Would need to 3d print the mold and then try. Goes without being said that it would require a conductive pad in the aswell...Wondering if it would work...TksLuca
TEK TDS 7054 Chrased HD - Page 1
Forum section: electronics / repair

author: Wallchee
author_rank: Newbie
timestamp: October 28, 2024, 10:30:17 pm
content: Hello communitythe hard drive on my beloved TDS 7045 has crashed🙈.Unfortunately I don't have any installation CDs and of course no backup copy😰Does anyone have a hard drive dump or images of the operating system and firmware CD?If it's relevant:TDS 7054 Ser.No. B020832Intel Motherboard SU810Acquisition Borad G9E-2858-00 CAGE 80009I would be very happy if someone could help me.

author: colorburst
author_rank: Regular Contributor
timestamp: October 29, 2024, 02:45:02 am
content: No idea if this is the correct set for your motherboard, but you can try using this pair of recovery disks:https://www.eevblog.com/forum/testgear/tek-csa7404-repair-project/msg4785077/?topicseen#msg4785077If those don't work, another option is to manually install Win98, then drivers, then product software fromhttps://github.com/exit-failure/tds7000On second thought, there is no point in trying those ISOs, the 845 motherboard is much newer than your 810. Unless someone comes forward with the correct set of disks, manually rebuilding is the way to go.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 29, 2024, 05:14:49 pm
content: same toughts rebuild from scratchthe official iso where made with powerquest, and they check hardware and may block from installingcolorbust is wrong : for theses old non "B" models the SU 810 where the last possible upgrade, crank the ram and cpu ...and the NLX type with Intel 815 chipset does exists, but the board is way bigger, i tried, but misses some voltagesthe B models use other boards

author: Wallchee
author_rank: Newbie
timestamp: October 29, 2024, 09:15:35 pm
content: Short feedback:First of all, thank you for the quick tips and information here.I have now received a HD from an 8000 system, whose Windows boots my system.I then uninstalled or manually removed everything that had to do with the 8000.I then received an image of the TDS 7054 firmware CD V2.3 from a German source.After the installation, the dinosaur is now working perfectly again and I am happy 🤸‍♂️...and by the way, there is now a copy of the HD in my safe 😉
Tek TDS 754D service manual? diagrams? - Page 1
Forum section: electronics / repair

author: Tracker
author_rank: Regular Contributor
timestamp: June 21, 2019, 06:55:39 pm
content: Hello kind forum people!Looking for a set of diagrams for the Tektronix TDS 754D ?A Google search came up with a so called 'service manual', but it only has block diagrams, no schematic or parts list.I received this unit from a nice donor, however it seems to have a PSU problem.On power on it goes into a 1 second cycle of flashing it's button lights and attempts to illuminate screen, then dies and repeats.I guess something is pulling the PSU down and triggering a reboot.Thanks in advance for any tips or links to the wanted manual.RegardsTracker

author: Tracker
author_rank: Regular Contributor
timestamp: June 21, 2019, 07:56:19 pm
content: Took a quick look inside and found the smoking gun so to speak....There is a power regulator on a digital board (underside of scope) which has released its smoke!The damage to the device is quite bad, making identification difficult...And when I unplug the digital board the scope powers up fine, but without any display data.Can anyone here tell what this Dpak part might be?I suspect its a 12v regulator 78M12 ?? the number 12 is visible top right, buy we also have 09 on lower right, but that might be the date code?Powering up the scope and measuring the input of the IC I can measure about +12v momentarily just before the scope cycles again, it might be higher than 12v but my meter cant quite catch it.I may need to scope it!It is identified as U1420 on the digital PCB.PCB image, damaged IC is middle image/right side of the pic.

author: PepaZdepa
author_rank: Contributor
timestamp: June 24, 2019, 09:09:18 pm
content: Hi, the pictures are invisible, send them again

author: PepaZdepa
author_rank: Contributor
timestamp: June 24, 2019, 09:15:08 pm
content: This one?

author: Tracker
author_rank: Regular Contributor
timestamp: June 24, 2019, 10:21:21 pm
content: Oh wow, thanks a million mate. I had ordered the 78m12 ... Just as well you replied. I could have fried the downstream circuit. 79m12 was unexpected.

author: PepaZdepa
author_rank: Contributor
timestamp: June 24, 2019, 10:37:48 pm
content: You're welcomeThe pic is from my 754D, schematic from TDS520 which is similar
Tek TDS1001B - display module pinout  - Page 1
Forum section: electronics / repair

author: twizzter
author_rank: Contributor
timestamp: July 10, 2025, 07:19:58 pm
content: I'm trying to bring back to life an oscilloscope that came to me in pretty bad shape - one of the challenges is missing ribbon cable between the mainboard and the LCD. I managed to find the pinout for the 18-pin connector on the motherboard side in the service manual, but i couldn’t find anything online for the display itself.The display connector is a 12-pin type, and it looks like pin 12 is GND, while pins 11, 10, 9, and 8 seem to be data lines.I’d rather avoid opening up the display unless it’s absolutely necessary.So my question is: does anyone know where i could dig up some info about the connections between the mobo and the LCD? Or maybe someone could help me out with the pinout for this display?Managed to find some old datasheets of similiar Nanya monochromatic LCD modules but what i found did not matched my findings and varied across different 12-pin models.The LCD model is LTBFBT696G11CKS.Thanks!

author: TinLethax
author_rank: Regular Contributor
timestamp: August 14, 2025, 12:35:43 am
content: Hi.You can have a look herehttps://pinoutguide.com/Electronics/TDS1001-TDS1002-TDS1012_M_pinout.shtml.I've made some probing on my TDS1012 a while ago to confirm the pinout.
Tek TDS210 burnt resistor - Page 1
Forum section: electronics / repair

author: kosomsk
author_rank: Regular Contributor
timestamp: October 06, 2019, 09:54:04 am
content: Hi all! I have a broken Tektronix TDS 210I need high resolution photo of mainbord or R136 valueR136 resistor near J302 (LCD connector on MB)Who can help ?)

author: JFJ
author_rank: Regular Contributor
timestamp: October 06, 2019, 12:35:00 pm
content: On my TDS200 series mainboard, R136 has 101 printed on its body (the 3 digit SMD resistor code for 100 Ω). The adjacent resistor (R137) is the same value.

author: kosomsk
author_rank: Regular Contributor
timestamp: October 06, 2019, 12:42:31 pm
content: Quote from: JFJ on October 06, 2019, 12:35:00 pmHi) PCB layout as on photo or old board, with PLLC flash memory ?

author: JFJ
author_rank: Regular Contributor
timestamp: October 06, 2019, 01:10:09 pm
content: It's the same PCB as in your picture, though the flash memory is a BGA package that's mounted in between the pads provided for your TSOP flash.

author: kosomsk
author_rank: Regular Contributor
timestamp: October 06, 2019, 03:35:06 pm
content: ThanksNear me bga too ) Picture from this forum. Tomorrow try to chek another elements in this part and change

author: kosomsk
author_rank: Regular Contributor
timestamp: October 08, 2019, 10:49:42 am
content: Damaged tantalum cap, this resistor and bipolar transistorThnks for all

author: Nepsh
author_rank: Newbie
timestamp: February 11, 2025, 12:58:15 pm
content: Quote from: kosomsk on October 08, 2019, 10:49:42 amHello, sorry to update an old inactive topic but I would like to have more information on how you repaired your oscilloscope. I currently have the same one that I'm trying to repair, and the R136 resistor heats up so much that it desolder itself. What did you change to repair yours? To tell the truth, I don't really know where to start and what to look for.Thank you very much for your time.
Tek TDS3034 input channel failure - Page 1
Forum section: electronics / repair

author: NH-GrizzlyBear
author_rank: Contributor
timestamp: October 30, 2021, 04:41:51 pm
content: One input channel works correctly at 1X only. The other three channels work perfectly.There are two, blue, 2-coil SPST latching relays up front, Panasonic NAIS TK1-L2-4.5V, and a white 2-coil DPDT latching relay behind, Takamisawa ASLD4.5W-K.I don't know which relay controls 10X switching, 50ohm switching, etc.pic from Dave's EEVblog -23564 to 23565 - Tektronix TDS3054 Oscilloscope Teardown Repair.Are there any other pics showing these relays more clearly?Any insight is appreciated.

author: SQ9MT_PL
author_rank: Contributor
timestamp: October 30, 2021, 07:01:04 pm
content: I propose to desolder the module (you have to do it anyway)And desolder the relays and check them.If the relays are OK, you will have to replace the entire module anyway.

author: voltsandjolts
author_rank: Unknown
timestamp: October 30, 2021, 07:37:29 pm
content: Refering to the picture posted in the OP, the three latching relays perform these functions:The blue relay on bottom left switches AC/DC coupling.The blue relay on bottom right switches 50 Ohm to ground, on output of above relay.The white relay selects attenuator network for [1,2,5,10,20 mV/div] or the networks for [100,200,500 mv/div] [1,2,5,10 V/div]The  represent 3 different signal paths into the custom amplifier / differential adc driver.The dark green areas are laser trimmed resistors, e.g. the input 50 Ohm terminator resistor is adjacent to the input ac coupling cap (at the very bottom of the module). I have a rough block diagram somewhere, I'll have a look for it.

author: bdunham7
author_rank: Super Contributor
timestamp: October 30, 2021, 07:41:12 pm
content: Quote from: NH-GrizzlyBear on October 30, 2021, 04:41:51 pmCould you be more detailed about this issue? Unless I've misunderstood what you mean, 1X/10X 'switching' is a scaling issue that has nothing to do with the input circuitry. So what exactly are you observing?

author: voltsandjolts
author_rank: Unknown
timestamp: October 30, 2021, 07:43:14 pm
content: The module has 58 pins soldered into the multilayer motherboard.It's a PITA to remove (speaking from experience) so you don't want to do that unless you are sure its broken and you have a working replacement. You are risking damage to the motherboard.IIRC I repaired my 3034B with a module from a 3034 but there was a slight difference between them. I had to put a short across two of the older module pins to get it working...I think...some years ago now.
Tek TDS310 looking for dump for DS1630 - Page 1
Forum section: electronics / repair

author: bengata
author_rank: Contributor
timestamp: September 18, 2023, 10:26:40 am
content: Hello, I need a dump with the calibration for the Тек TDS310 .

author: bengata
author_rank: Contributor
timestamp: September 21, 2023, 04:28:39 pm
content: Hello . I was able to fix it and it is now running. But there is a problem with the calibration. And I can't handle something. Can you direct me where to look for a defect
Tek TDS360 floppy drive and LCD replacement. - Page 1
Forum section: electronics / repair

author: philwong5176
author_rank: Unknown
timestamp: September 11, 2021, 03:18:28 pm
content: Hello:I have 2 issues with my Tek TDS360: the floppy drive is dying, and the CRT is getting very dim. I would like to replace the floppy drive with a SSD or an SD card cage, and find a suitable LCD to replace the CRT.Would veterans of these upgrades share their experience here? I am aware the final upgrade cost would exceed the current value of this scope.Thanks.

author: pcwrangler
author_rank: Regular Contributor
timestamp: September 12, 2021, 04:07:32 am
content: What is the floppy drive doing? Have you tried cleaning it?

author: james_s
author_rank: Super Contributor
timestamp: September 12, 2021, 05:07:39 am
content: Are you sure it's the CRT itself and not a fault with the monitor electronics? Does it get blurry if you turn up the brightness pot inside? It's a standard VGA resolution monitor so it shouldn't be hard to connect a modern LCD if you can find one that fits physically.

author: philwong5176
author_rank: Unknown
timestamp: September 13, 2021, 04:52:37 pm
content: The floppy drive keeps spinning once a disk is inserted, and does not red or write from/to the disk.

author: pnv57
author_rank: Contributor
timestamp: September 14, 2021, 11:47:44 pm
content: Are you sure that it is formatted correctly? Is the spinning intermittent or constant? I had a similar issue on my tekmate when I tried 1.44M formatted 3.5" floppies in it, when it needs 720K format.
Tek TDS500/600 series scopes capacitor replacement best practice - Page 1
Forum section: electronics / repair

author: rodd
author_rank: Regular Contributor
timestamp: March 20, 2022, 06:01:05 pm
content: Dear all,I have a TDS680A in which I want to to a full recap job.I have been reading threads with different suggestions, like:1- replace all by 33uF/35V electrolytic smd capacitors2 - replace all by 33uF/??V tantalum smd ( what should be the correct Voltage spec for tants?)3- replace all by same value as original using radial electrolytic capacitors with lead bent to fit the solder pads.Can you post your experience/views on this subject?Indication of the preferred cap replacement manufacturer/product number would be greatly appreciated.Best regards,Roger

author: wn1fju
author_rank: Frequent Contributor
timestamp: March 20, 2022, 09:48:42 pm
content: On my TDS520, I used electrolytics to replace all the SMT caps (a mix of 33uF and 10uF). If I remember, I used Panasonic low ESR, 105 degree radial capacitors for most of them. There were some caps under a shield, so I had to use smaller height ones for those and I could only find 85 degree caps for them. The replacement method was 1) twist off the SMT cap with pliers, 2) unsolder the leftover leads still attached to the board, 3) scrub the area with alcohol, 4) look through a magnifying glass for any broken/corroded traces/pads around the cap, 5) cut and bend the electrolytic leads into a short "L" shape, 5) solder them onto the pads, 6) scrub off any flux with alcohol. It goes fairly quick once you get going.My TDS520 had plenty of SMT caps that were oozing as well as plenty that were not oozing but had lost almost all capacitance. You really can't tell just by looking, so it is best to replace all the SMT caps on all the boards as you are planning to do. And, of course, look in the power supply for any of those gold-colored Rifa suppression caps - those should be replaced without question.As you have indicated, there are lots and lots of threads on repairing these TDS scopes. Good luck.
Tek TDS5104B has developed acquisition issues - Page 1
Forum section: electronics / repair

author: emcee2
author_rank: Newbie
timestamp: March 16, 2023, 06:11:31 pm
content: Hi. We have a TEK TDS5104B. It was working fine, or so I am told. Now it reports Acquisition and Trigger errors on boot into the TekScope program.I've opened it up... poked around a bit. The supplies (+/-15; +/- 5) on the acquisition board are present, though there is a LM2941S low drop-out adjustable regulator with 15V in and 11.2 Volts out. Seems odd. I'm assuming that should be 12V but, but with no schematic its a bit difficult to figure what the load is. Maybe something is dragging it down.I'm wondering if that regulator is feeding the hybrid/bonded circuits under those input cans. Can anyone confirm? I haven't yet gotten to the point of pulling the board out... time, and inclincation being my hurdles at the moment.Any insight is most appreciated. Cheers!

author: mikehank
author_rank: Regular Contributor
timestamp: March 17, 2023, 05:43:40 pm
content: Hi,Could you be more specific as to the error messages? The input hybrids do go bad but I don't think they would cause trigger errors. Most of Tek's scope bypass the front end when testing the triggers.
Tek TDS724D to TDS784D, acquisition board swap possible? - Page 1
Forum section: electronics / repair

author: Jan Steinman
author_rank: Contributor
timestamp: October 13, 2025, 08:28:27 pm
content: I've successfully upgraded my TDS 724D (2+2 channel) to a TDS 784D — minus two channels — by removing a resistor and four capacitors from the original acquisition board. This procedure is nicely documented on this website.Now I'm lusting after four full channels. The 724D only has two "real" channels, and two "aux" channels with vastly reduced functionality.I see the 724D acquisition board has spaces for four large ASICs that are missing, which I assume provide the missing two full-feature channels.Can an acquisition board from a 754D, 684D or 784D be swapped in to provide four "real" channels?I've read that some acquisition boards cannot be used unless the display board is running certain firmware. I seem to have v6.2.1.e.Thanks for any advice offered!
Tek TDS744 screen flicker and color change - Page 1
Forum section: electronics / repair

author: PartialDischarge
author_rank: Super Contributor
timestamp: December 26, 2019, 06:53:43 pm
content: I can feel the screen of my TDS744 is about to die, as soon as I turn it up it quickly changes colors and flickers fast, this is a video:Any idea what could it be?

author: madao
author_rank: Frequent Contributor
timestamp: December 26, 2019, 07:45:18 pm
content: https://www.eevblog.com/forum/repair/tds744a-color-display-flicker/Reason: capacitor leakage on PCB with EPROM in CRT unit.Replace eletrolytics and washing PCB.
Tek THS720 BNC replacement - Page 1
Forum section: electronics / repair

author: 1audio
author_rank: Frequent Contributor
timestamp: July 26, 2021, 10:57:27 pm
content: The THS series of handheld scopes use BNC's with plastic barrels that are fragile. I have one that was abused with the P6015 probe to the point where the connector is quite intermittent. These are odd BNC's. I would like to get replacements that are correct if they can be had. Otherwise I'll just mount a pair of generic isolated BNC's. Does anyone know a source?Also a source the the "stand" in the back which is missing?

author: giovannirat
author_rank: Regular Contributor
timestamp: July 30, 2021, 07:40:18 pm
content: You can probably try the following oneshttps://www.aliexpress.com/item/32886114304.html?spm=a2g0s.9042311.0.0.27424c4dR1R01k

author: 1audio
author_rank: Frequent Contributor
timestamp: July 31, 2021, 04:39:57 am
content: Thanks for the tip. They are cheap enough that i'll give them a try. I have also found some other options which I'll share when I see if they can work.
TEK TLA510 setup change - Page 1
Forum section: electronics / repair

author: jmelson
author_rank: Super Contributor
timestamp: December 06, 2020, 03:33:58 am
content: I have a TLA510 at work that we don't use often. I fired it up and could not connect with my new desktop, which has a different IP than the one used when I last used the TLA. So, I tried to get in through the serial port. At power up, it reports mainframe power usage and self-test of modules.Then, I get a bunch of gibberish on the screen, and then after the booting completes (HDD light off) if I hit enter I get "this system is configured for 92XTerm operation, but is not in use."The manual says to set for boot> prompt, which works, and then type /configThis does something, but I cannot see the menu I am supposed to see.I don't know if something has gotten corrupted (hard drive or EPROMS) or that itswitches baud rates for a while. I left the baud rate switches both up for 38.4K(the default) and I do see a few characters in the gibberish that look like the expected output.Anybody remember this ancient machine?Thanks,Jon
TEK3054B- What are the symptom of a bad Dallas NVM/RTC? - Page 1
Forum section: electronics / repair

author: jwet
author_rank: Frequent Contributor
timestamp: December 28, 2024, 08:19:50 pm
content: My twenty year old, owned since new, TEK3054 scope doesn't keep proper time and must be dropping NVM settings- what does a TEK3054B do if it has a bad RTC?The older ones wouldn't boot- mine boots and acts fine but loses time.

author: inse
author_rank: Super Contributor
timestamp: December 28, 2024, 08:48:19 pm
content: And the last settings are being lost, thats what I noticed

author: jwet
author_rank: Frequent Contributor
timestamp: December 29, 2024, 01:19:07 pm
content: i have a symptom where my machine after some time being on will go into sort of crash/boot loop. Most thought this was power supply but I don't think it is- happens with external power.

author: m k
author_rank: Super Contributor
timestamp: December 29, 2024, 04:13:11 pm
content: Back in the day slowing RTC time was a first indication of weak battery.So if you need a backup, do it when you can.
TEKDPO4104  Front panel key problem - Page 1
Forum section: electronics / repair

author: hitecelec
author_rank: Regular Contributor
timestamp: September 16, 2019, 08:02:53 am
content: Hi AllFront panel bezel key 1(config) from the left side and key 7 not functional. Suspect Flex ckt.found the part number 260-2813-01 . does it include the flex circuit as well as the elastomeric assythanks in advanceRegardsAnand
Tekpower HY5005E-2 Current Limiting Issues - Page 1
Forum section: electronics / repair

author: BlownUpCapacitor
author_rank: Frequent Contributor
timestamp: October 20, 2024, 07:47:35 pm
content: Hello!My Tekpower HY5005E-2 is experiencing some current limiting issues. It behaves in a really strange way compared to my other bench power supplies.Voltage works completely fine along with the current readout. I can use it to power my projects at two amps 50v no problem. The issue is that, when I try to set the current limiting by shorting the output, the voltage immediately drops to zero (as expected), but the current also drops. It will only supply a maximum of 110mA even with the current limit set to the max.As mentioned before, the supply will have no problem running two amps, but when the output is shorted to run the current, it doesn't work. The strange thing is if I apply a small load and steadily increase it, it won't have this issue. I can still set the current limit this way and it'll work, but the exact current limiting setting is all over the place.I honestly have no idea how to start troubleshooting this power supply. It does seem to be of the generic dual supply kind so maybe someone has experienced a similar issue and has found a solution?It has been like this ever since I pulled it out of the dump. Has served me well for more than a year. Thought it's about time to get it fully working.

author: indeterminate
author_rank: Regular Contributor
timestamp: October 20, 2024, 10:04:24 pm
content: Do both power supplies exhibit the same problem , if so then the fault is in a common section of the supply or is just a design bug.unless sumthing is noticeably cooked or there is a dry joint then start by reverse engineering the circuit from the current shunt.once you have a schematic of the current measurement circuit it will make it easier to work out where the problem isand chk the low value electrolytics cap's to

author: BlownUpCapacitor
author_rank: Frequent Contributor
timestamp: October 20, 2024, 10:57:51 pm
content: Quote from: indeterminate on October 20, 2024, 10:04:24 pmWell, the left supply is more "normal" but still has issues. I can never get the current limiting to zero. When shorted, the left supply will only go to a minimum of 2.5 amperes, while the absolute maximum shorted is 3.6 amperes. These values are quite erratic and change.The right supply is as described previously. But like the left one, I can't get it to current limit at zero, unlike my other supplies.Quote from: indeterminate on October 20, 2024, 10:04:24 pmI'll try those.
Tekpower TP1803D Variable Power Supply, no power - Page 1
Forum section: electronics / repair

author: arcfault
author_rank: Contributor
timestamp: September 13, 2023, 02:52:39 am
content: I have a Tekpower TP1803D that I got off Ebay. I was able to get a refund on it because it's not putting out any power. Pretty odd.Turns on fine. If I put a voltage on it, it reads the voltage on the display. Seems to cycle from constant voltage to constant current as one might expect when messing with the voltage and current knobs.Nothing funny looking, smelling, etc, after taking the case off.Would appreciate some advice on where to start.Thank you!

author: Shonky
author_rank: Frequent Contributor
timestamp: September 13, 2023, 07:32:11 am
content: Looks super cheap and nasty - careful with mains inside.The back board on the heatsink looks to be the actual supply so I'd be looking at whichever lines are the input from the transformer. Check for AC around 20-25V. Then should be a rectifier and the big filter cap. Check for DC there (and also AC).With it off it may be worth checking the windings for continuity. It seems the front board is working - possibly running off a separate winding to the supply board. That also rules out the mains side primary winding.

author: arcfault
author_rank: Contributor
timestamp: September 13, 2023, 02:37:50 pm
content: I was thinking as well that there must be an extra winding just to power the basic circuitry. That's a great place to look, thank you!If I can't get this one going, what would be a more reputable linear power supply? I've been wanting to test for ripple in solar charge controllers, but if I'm starting with ripple (I also have a switching power supply) I think I won't have reliable results.

author: u666sa
author_rank: Frequent Contributor
timestamp: September 13, 2023, 02:52:36 pm
content: Well wait a minute. Just because it's crap, doesn't mean it has the right to exist. My yaxun made me a ton of money back in 2014. Back then there was flip phones, nokias, and very few iphones. It is still useful. I still use it to charge stuff.First thing you do is check that transformer gives you power.Then you check all the caps -- desolder and check ESR... You should have ESR meter. Here is a link to one --click-- trust me, it's a money maker! If no ESR meter, replace all caps, but beware, new comes sometimes are bad.Then, if that don't help. We'll look and see further.
Tekronix TDS7404 DPO No power-on response - Page 1
Forum section: electronics / repair

author: sucharitha
author_rank: Newbie
timestamp: March 03, 2022, 11:08:02 am
content: Hi,iam a newbie here.facing problem with Tek TDS7404 DPO scope.I already posted In Existing thread:https://www.eevblog.com/forum/testgear/tek-csa7404-repair-project/How do I get my post/topic under: ELECTRONICS: REPAIRpls suggestAny help is helpful to me

author: sucharitha
author_rank: Newbie
timestamp: March 03, 2022, 11:26:18 am
content: Can I once again post my problem here,but that gonna become spammingdesperate to repair the DPOthanks u all

author: sucharitha
author_rank: Newbie
timestamp: March 15, 2022, 07:01:42 am
content: hi,Tektronix TDS7404 further diagnosis:In stand alone condition standby led glows on PSU(smps based) when main switch on.

author: sucharitha
author_rank: Newbie
timestamp: March 15, 2022, 07:07:34 am
content: hithis is with rear power distributuion board , but debug powern open

author: charlyd
author_rank: Frequent Contributor
timestamp: November 21, 2022, 08:19:50 pm
content: Hi long time no see how did you manage with your psu?
Tektronics 2225 Faulty Trigger Circuit - Page 1
Forum section: electronics / repair

author: woood777fly
author_rank: Newbie
timestamp: July 25, 2020, 02:44:03 pm
content: Good Evening I have a tektronix 2225 oscilloscope that I have not used for a number of years. I needed it to measure the output from a 26mhz Xtal oscillator but I cannot see a sensible waveform. It just looks like a blurr. The waveform from the 1khz test point can be held still with a little fine tuning on the 'hold off' pot but any higher frequency cannot be displayed properly. The trigger LED only comes on briefly on the 1khz test point when I slide the 'mode' switch from one side to the other, on higher frequency the trigger LED does no come on at all. Does anyone have any ideas on where to look on the pc board for the trigger fault. I have a copy of the workshop manual but dont know where to start looking. The circuit boards are in lovely condition no corrosion and no obvious burned tracks although at the moment I cannot see the front board without taking the front plastic panel off the scope. Kind Regards

author: jdragoset
author_rank: Frequent Contributor
timestamp: July 25, 2020, 09:42:46 pm
content: The detailed trigger schematic is schematic "diamond 3", as shown on the block diagram.First try to exhaust all front panel possibilities, try external trigger in, etc. to verify no trigger signal under any conditions.Also check for front panel for LF/HF trigger reject.
Tektronics 2246 acting funny on CH2 - floating - Page 1
Forum section: electronics / repair

author: tkamiya
author_rank: Super Contributor
timestamp: September 19, 2020, 02:31:05 am
content: I have a Tek 2246 I've been working on for few months, on and off.This scope works fine with exception on one thing. Channel 2 acts out after few minutes from cold start. The trace goes up and down by about 1 unit on graticule, sometimes slowly, sometimes quickly. Sometimes it almost forms a wave form. The behavior does not change with voltage divider setting or horizontal sweep setting. (of course, scan speed changes but vertical movement stays the same) On Ch2, I can actually make measurements and they are accurate. It's just that it acts like its ground is floating. It behaves the same with input grounded as well.I've replaced a vertical control pot on the front screen. Cold sprayed everywhere. Tapped everything with back of screw driver. Nothing I did changed behavior. It is acting as if there is a cold solder joint or intermittent connection somewhere but I am unable to find it.If anyone has any ideas, I'd be thankful of hearing about it.

author: Rollin Hand
author_rank: Regular Contributor
timestamp: September 19, 2020, 06:00:42 pm
content: I have had some similar experiences. Unless you have a lot of free time and nothing better to spend it on my guess is that chances are you will waste much time and not get far. From a practical point of view I would suggest finding a pro.

author: tkamiya
author_rank: Super Contributor
timestamp: September 19, 2020, 07:02:52 pm
content: That is very true. This is only a 100MHz scope and its monetary value is quite low. I've also spent way too much time working on it. Continuing like this is simply.... crazy!However, I do this for fun and relaxation.So... if you have any unwanted eBay wins, please contact me privately. I will properly dispose of them for you.
Tektronics TDS1020 - Page 1
Forum section: electronics / repair

author: Gina W
author_rank: Newbie
timestamp: December 12, 2022, 01:59:43 am
content: Have a couple of TDS1020 that do not work.They light up with screen backlight but no self check and no display. I would like a schematic of the power supply and some basic steps on how to reload the firmware.,Fingers crossed

author: james_s
author_rank: Super Contributor
timestamp: December 12, 2022, 03:42:28 am
content: If it's anything like the TDS3000 series there are no publicly released schematics. The "service manual" tells you how to determine which board to replace.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 12, 2022, 04:10:53 am
content: This is to Tek's service manual for the 1000 series. Tek 1020 is not shown. Is that the correct number? If it is the same series, search for the TDS1000 series.https://www.tek.com/en/oscilloscope/tds1002-manual/tds1000-tds2000-series-service-manual

author: coromonadalix
author_rank: Super Contributor
timestamp: December 13, 2022, 02:31:15 am
content: As usual you wont have any schematics in them ...

author: jpanhalt
author_rank: Super Contributor
timestamp: December 13, 2022, 06:45:49 am
content: Of course, Tek probably won't have the schematics. The point I was raising was whether TDS1020 was the correct model as that model was not included in the manual for that series. OP hasn't responded, so it's a moot point.
Tektronics TDS320 Sec/Div knob not working - bad encoder? - Page 1
Forum section: electronics / repair

author: TheForgottenKing
author_rank: Newbie
timestamp: June 23, 2023, 03:37:57 am
content: Hello everyone,I recently purchased a TDS320 for $50. Quite a good price for what it is, and it is mostly working well.The only issue I seem to have is that the horizontal adjustment knob doesn't do anything. I'm not sure if I'm just using it wrong (this is my first time using an oscilloscope), but it seems to just be dead.What are my next steps? I've read with other models the best move is to attempt cleaning it, but is it possible to replace the encoder if needed?Thanks.

author: TheForgottenKing
author_rank: Newbie
timestamp: June 25, 2023, 05:27:04 pm
content: Update for anyone who finds this thread:The metal tabs that contact the encoder were corroded and broken off, so I cleaned what remained, made a soft edge, and bent them to make contact with the PCB. This mostly resolved the issue. Sometimes the dials miss a turn or double up but this seems a tuning issue that can be resolved and it doesn't happen often.
Tektronix 011-0099-00 5W 50ohm Termination - Page 1
Forum section: electronics / repair

author: RaymondMack
author_rank: Regular Contributor
timestamp: July 20, 2021, 03:29:08 am
content: Does anyone have a datasheet or manual for the Tektronix 011-0099-00 5W 50ohm termination? I tried looking but couldn't find anything. I was curious about the bandwidth and pulse power capability.Also, has anyone attempted to replace the BNC connectors? The female connector on one of my terminators looks like it should be replaced. The connector on the left has a pretty loose center contact when compared to the one on the right.I assume, that to put this together, the termination resistor is soldered directly to the female connector with some sort of leaf spring assembly used to touch the inner shell, then the male pin is soldered onto the other end and it just free spins as the female end is threaded into the housing. I guess Tektronix could have used a coaxial resistor. Most just use SMD parts soldered between the center pin and a leaf spring touching the shell.Any thoughts on this? Maybe the expanded female contacts aren't as big a deal as I'm making them out to be?

author: jdragoset
author_rank: Frequent Contributor
timestamp: July 20, 2021, 12:03:47 pm
content: No solder, the assembly is entirely mechanical threaded connections.

author: David Hess
author_rank: Super Contributor
timestamp: July 20, 2021, 06:10:48 pm
content: Those were actually made by someone else; Probe Master sold the same terminator.The only data I have seen on them is in the Tektronix catalogs, 5 watts, SWR < 1.1 from DC to 100 MHz, but I see identical results compared to higher frequency attenuators up to at least 300 MHz.

author: RaymondMack
author_rank: Regular Contributor
timestamp: July 20, 2021, 09:11:54 pm
content: Quote from: jdragoset on July 20, 2021, 12:03:47 pmHave you pulled one apart before? Would I be okay to unthread the female connector and not damage the load resistor?

author: jdragoset
author_rank: Frequent Contributor
timestamp: July 20, 2021, 10:11:24 pm
content: When I got mine it was intermittent, both through the BNC connectors and 50 ohms to ground.Figured what to loose and unscrewed the male BNC end (flat open end wrench).The male pin comes out and is screwed onto a rod.the resistor is a flat carbon disc with a center and outer metallized ring.The outer ring is held with a threaded ring like the lens of a microscope.The inner ring is held with threaded extensions from the BNC connectors pin and socketI was able to tighten all the threads and get reliable continuity through as well as 50 ohms to ground.Did look for a breakdown diagram online but did not find anything.