hybridfree/eevblog-posts huggingface dataset:
DS1287 question - Page 1
Forum section: electronics / repair

author: alank2
author_rank: Super Contributor
timestamp: February 07, 2023, 03:51:19 am
content: I've got a DS1287 with an internal lithium cell that is dead. There are many guides on fixing these. I drilled it to expose the two battery contacts and disconnected the negative side from the internal lithium coin cell. Then if I hook up a CR2032 to it I am surprised to find it consuming 12mA which seems way too high. I'm not sure what the internal battery is, but I doubt it has the 225 mAH that the cr2032 does and at 12mA it would be dead in 18 hours or so. The spec says it should last 10 years with the internal coin cell! I'm guessing it would normally be in the 2.5 uA or lower category?

author: Greybeard
author_rank: Frequent Contributor
timestamp: February 07, 2023, 08:53:57 am
content: Have you removed the old cell?

author: Ian.M
author_rank: Super Contributor
timestamp: February 07, 2023, 10:29:07 am
content: Alan *SAID* he disconnected its negative side.However I'm wondering if there's any possibility its got two coin cells in parallel, and he's only disconnected one?Check with a small strong magnet to confirm there is only one cell, (as parallel cells would usually be side by side, not stacked), then take a very close look at where you drilled the negative connection - maybe there's a wisp of metal still shorting the break.

author: alank2
author_rank: Super Contributor
timestamp: February 07, 2023, 12:57:31 pm
content: All the guides show disconnecting the old cell by severing the connection on pin 13 and that is definitely cut. I think there is only one cell and from the pictures I saw it looked like the legs were bent upwards, but I could try drilling out the solder and doing more testing.

author: retiredfeline
author_rank: Frequent Contributor
timestamp: February 07, 2023, 08:16:16 pm
content: If you can measure any voltage at all between those IC pins with nothing else wired to them, the internal (single) lithium cell isn't disconnected.

author: alank2
author_rank: Super Contributor
timestamp: February 08, 2023, 01:11:04 pm
content: It is 0V between the two pins for the IC, but this IC has an issue. Connecting a 2032 to those pins and it is back as 12mA. I drilled another DS1287 I have and it doesn't have that issue.

author: alank2
author_rank: Super Contributor
timestamp: February 26, 2023, 03:44:44 pm
content: Still working on these. The one that doesn't have the high current still doesn't work right with a new cell connected to it. I've got a couple of nice CR2032 battery holders so I am going to try my luck at the other two DS1287's that say their battery is depleted, but I'm going to dremel them a bit more slowly to see what I can do. I've also got two DS1872's that report their internal battery still good (register D has bit 7 set). One question I have for anyone who has ever put a new battery in one of these is - did register D bit 7 come back after the new battery? Should that happen?
ds216+ H255L - Page 1
Forum section: electronics / repair

author: GOD
author_rank: Contributor
timestamp: November 04, 2019, 11:10:01 am
content: hey guys what is the h255L component is a active or passive type. how do i tell if its it active or not. Also is the component a crystal or a oscillator? This is in a synology ds216+ nas

author: coromonadalix
author_rank: Super Contributor
timestamp: November 04, 2019, 11:19:30 am
content: Its a crystal oscillator with its 2 associated capacitors, normally you can test it with a scope on x10 impedance, youlll be able to see its frequency output on some pinsOne of the two round pads near the caps will show you the frequency ??The ic is an Intel I211 Lan controller, the datasheet says 25 mhz clock

author: GOD
author_rank: Contributor
timestamp: November 05, 2019, 10:11:55 am
content: thanks for replies currently don't have oscilloscope currently. I did get the fact it is a 25mhz but is a active or passthrough model?
DS345 Successfully repaired - Page 1
Forum section: electronics / repair

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 17, 2022, 10:11:52 pm
content: Picked up this SRS DS345 for a reasonable price with the following self test error on boot up...The manual has a listing of self test errors, with helpful but vague areas to check.It would be better to include "check surrounding circuitry as well."After much troubleshooting I found the output of the DAC was a bizarre looking signal. Two and a half times the expected frequency and DC offset on both diff. outputs.Checking all the digital inputs from the ECL translator chips (MC10124) I found that pin 14 (MSB) on the DAC had no input. That led back to U504D. Changing U504D solved the issue. Now passes all tests.Hope this can help someone spend less time troubleshooting.

author: bostonman
author_rank: Super Contributor
timestamp: October 18, 2022, 06:25:41 pm
content: I assume this wouldn't be applicable to the problem you and I have discussed in the other thread?https://www.eevblog.com/forum/repair/standford-research-ds345-error/msg4436569/#msg4436569

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 18, 2022, 06:36:21 pm
content: No, unfortunately not!Still trying to track that issue down!

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 20, 2022, 01:46:26 am
content: Quote from: bostonman on October 18, 2022, 06:25:41 pmSo, I was working not on the original DS345 with the drifting offset you mention evidenced at U600 on the lower board. I did, however use it (the drift unit) to swap two major IC's, the ASIC DDS345 (U300), and also it's DAC, the TRW TDC1110, (U500).The problem I fixed (bad MC10124) in this other DS345 is working good... but it MAY have new problems!!! BECAUSE... the drift in the original DS345 seems to have stopped solid. I can adjust the offset trimpot now and it seems to hold the DC setting solid. Will know more come morning after a soak overnight. There is, of course possibilities there were bad connections to the IC's as another possible cause. The unit I just repaired now has the possible bad IC (one of the two). I do know that the TRW TDC 1110 DAC is no longer made. You cannot get it on ebay either. TRW Electronics is defunct. The later DS345 units do not use it. They have a daughter board soldered on top of that area of the top board with a new DAC and circuitry. I will now of course be checking the "repaired" unit to see if the drift problems transferred to it. That would rule out bad connections. Stay tuned!

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 20, 2022, 01:39:20 pm
content: So as the saying goes... all the best laid plans of mice and men...We had a power outage last night, and this was not under UPS backup, although the generator and ATS did kick in. I need to restart the setup.

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: October 20, 2022, 08:32:24 pm
content: Unfortunately, I inadvertently pulled my monitor wire off from the output of U600Sorry... total false alarm, it still has the drift
DS8202 oscilloscope screen frozen on startup - Page 1
Forum section: electronics / repair

author: mountainbiker000
author_rank: Newbie
timestamp: January 25, 2025, 03:52:30 am
content: What could be causing this oscilloscope to freeze after start up with lines on screen?

author: m k
author_rank: Super Contributor
timestamp: January 30, 2025, 07:45:55 am
content: Lines can mean that picture update has stopped or the whole machine has stopped.If picture without lines is never happening the picture generating system is probably the reason.
DSE-3800 / EP-225 Power supply no output - Page 1
Forum section: electronics / repair

author: Glion
author_rank: Newbie
timestamp: August 01, 2025, 01:16:06 am
content: Hi,I have a DSE-3800 / EP-225 Power supply. it has no voltage at the output, although it turns on and the fan pins etc. From memory and it was a long time ago, I think I broke the power supply when I reverse connected a 12V car battery.The fuse it all good, it turns on (although the power LED does not glow), the fan spins, the warning LED flashes once at power on, and glows briefly a couple of seconds after switching off.I've tested the transformer output and its 23V, this is feed through the transistors to the output, The collector is 23v as expected and so is the base, the emitter is 0v.Would this mean the output transistors are blown?The base voltage 23v is very high or is this normal as it being turned on super hard as there is no output? (on further testing with the power off there is zero resistance between the B-C)What advise would you give so I can start trying to working what component/s have failed?Link to power supply schematic and details etc:https://pa0fri.com/Diversen/EP925/ep925eng.htm

author: Harry_22
author_rank: Frequent Contributor
timestamp: August 03, 2025, 05:40:07 pm
content: Hi, Glion!You will find some info here:https://www.eevblog.com/forum/repair/faulty-dse-d-3800-power-supply-similar-to-manson-ep-925/BRHarry
DSE T2000 - Page 1
Forum section: electronics / repair

author: jbchild
author_rank: Newbie
timestamp: January 15, 2023, 05:58:36 am
content: Hello - I'm attempting to repair a DSE T2000 and have hit a dead end, so am looking for help/suggestions.The thermocouple was open so I replaced the element (it is 60w vs 48w, so hopefully that is not a big issue.)I have found an owner's manual online, as well as a friend who has one. Unfortunately the schematic does not match the PCB.The PCB referenced in the manual is a 66-168001, whereas my station has a 66-168001C PCB, and it is a very different board.Major issue is the use of the LM358P op amp in my station as opposed to the LM1458 op amp in the schematic.Are there any schematics / owners manuals about based on the 66-168001C?Thanks in advance** Does anybody have any suggestions on how to calibrate this? With the new element and thermocouple the minimum temp is now over 300c.
DSLR Nikon D60 mirror mechanism repair - Page 1
Forum section: electronics / repair

author: bborisov567
author_rank: Regular Contributor
timestamp: August 18, 2022, 07:06:46 am
content: I coundnt seem to find a specific dslr repair forum so i decided to write here. I got this D60 and the mirror is always up. It is not stuck, i can move it down manually but it always goes back up. My question, before I disassemble the camera, is could it be something fixable or i will need to get a new mirror box assembly. Also if you now some place where dslr repairs are discussed, please let me know. Thanks in advance.
DSO-142L, Capacitance & Voltage Value (C12) - Page 1
Forum section: electronics / repair

author: arehumansturingcomplete
author_rank: Newbie
timestamp: January 25, 2024, 04:02:11 pm
content: Greetings EEVBlog forum,My latest (personal) project is swapping the electrolytic capacitors out on a DVE Brand DSO-142L Rev: C switching power supply (Lot# 200410). This PSU board is for a EO1013 Series HP KVM switch.Output: +5.1V / 2.4A, -5V / 0.5AInput: 100--240VAC 50/60Hz 0.7AThe electrolytics are swapped, no issue there--but the SMD ceramic capacitor for the +5V filtering (solder side) cracked in the process of installing the last can. Designator C12.I'm a solder monkey & not an engineer, so I'm a little out of my depth on what the circuit can tell me about what capacitance value I need to get as the replacement.I'm attaching photos of my board, along with a creepy diagram of the model I've found online.Any input will be helpful, thank you!
DSO-X 2012A Power supply repair - Page 1
Forum section: electronics / repair

author: lern01
author_rank: Regular Contributor
timestamp: November 23, 2024, 06:52:11 am
content: A DSO-X2012A power supply is faulty and has no 1V output. It is found that the Q300 in the multi-channel power output board (75019-26424) is blown up. It should be a MOS tube, but I don't know the model. Which friend can tell me? Thank you very much!

author: Harry_22
author_rank: Frequent Contributor
timestamp: November 23, 2024, 08:26:21 am
content: What is the input voltage for Q300?PSHave a look on Q202 and Q203.

author: lern01
author_rank: Regular Contributor
timestamp: November 23, 2024, 10:01:00 am
content: Quote from: Harry_22 on November 23, 2024, 08:26:21 am13V。I found out, it's FDSAS6982AS。But the parameters of U305 cannot be found (3011), The 13th pin to ground (digital multimeter diode range) is only 0.056 in both forward and reverse measurements, while the 13th pin to ground of other 3011s is about 0.12 (reverse measurement on the circuit board). It is estimated that it has been damaged.

author: iAleks
author_rank: Regular Contributor
timestamp: November 23, 2024, 12:54:06 pm
content: Quote from: lern01 on November 23, 2024, 10:01:00 amMay be thisNCP3011

author: CapLeaker
author_rank: Regular Contributor
timestamp: November 25, 2024, 12:40:56 am
content: It only has one 12v, 10A output? How old is it?https://www.badcaps.net/forum/troubleshooting-hardware-devices-and-electronics-theory/troubleshooting-game-consoles-other-weird-devices/86804-agilent-dso-x-2012a-no-power-repair
DSO-X 3024A - repair worthy or not? - Page 1
Forum section: electronics / repair

author: mkz
author_rank: Newbie
timestamp: December 10, 2021, 03:40:34 pm
content: HiI found a scope on sale as non- working... seller claims on power on there is only a quick flash of the screen....and then nothing...He did say he saw only one visible sign of damage on the board, on U3602 - but in the other photo it looks like some oxidation on the USB port etc?Can anyone identify it for me hard to make out on the photo?Can anyone advise, is it worth buying for $450 as a repair project?thanks

author: wraper
author_rank: Unknown
timestamp: December 10, 2021, 04:01:57 pm
content: Looks like failure is a consequence of liquid damage. Still IMHO a good deal if you know what you are doing. If you never repaired liquid damaged stuff, or don't have much of repair experience, then staying off it may be a wiser decision.

author: Pinkus
author_rank: Frequent Contributor
timestamp: December 10, 2021, 04:18:52 pm
content: Difficult to decide ... the exploded chip is a LT3580 (DCDC Converter). Regarding the liquid signs on the power supply PCB I would assume that the liquid leaked into the power supply and the chip was destroyed by overvoltage. The risk is high that many other components are also defective.But $450 is good deal, I would give it a try as you would then still have some spare parts to sell.
DSO138 2.4" TFT Digital Oscilloscope perpetually crashing - any solution? - Page 1
Forum section: electronics / repair

author: ausername
author_rank: Newbie
timestamp: August 08, 2020, 07:08:25 pm
content: Our DSO138 2.4" TFT Digital Oscilloscope is perpetually crashing. It turns on, the wave form moves up the screen, the oscilloscope says it's rising in voltage even though it's not rising in voltage, and then it crashes after saying it was rising in voltage a little. The reset button is not helping to resolve this. Does anyone have any solution for this or any resources we can go to to find out how to resolve this issue?
DSO1511e Plus Firmware Backup Flash Dump - Page 1
Forum section: electronics / repair

author: rtek1000
author_rank: Contributor
timestamp: June 16, 2022, 06:14:38 am
content: Hello,Could someone please send a copy of the contents of the Flash memory of the DSO1511e?I bricked my DSO1511e but was able to recover it with help from a friend after compiling the bootloader and combining the original firmware, but the boot image is still missing.I could try using the Ghidra program to try to locate some image stored in the firmware, but I believe it's easier to back up, and I also believe it's good for users to know how to do that backup.The procedure for backing up Flash should be as follows:1- Create an SD Card with the USB Port Access Tool2- Insert the SD card into the slot on the DSO1511e board3- Press and hold the DSO1511e power button4- Connect the USB cable to the computer and the DSO1511e5- Read Flash contentReference of commands and procedures I left described in this repository:https://github.com/rtek1000/DSO1511e_Plus_UnbrickThank you!
DSO4102c waveform generator broken? - Page 1
Forum section: electronics / repair

author: jjedele
author_rank: Newbie
timestamp: October 03, 2022, 09:27:20 am
content: Hey all,First post in this forum, despite having watched the Youtube channel for a while now! I'm an informatics person with a hobby interest in electronics and just got a used KKMOON (Hantek relabelled?) DSO4102S for cheap as my first oscilloscope to play around with.The measuring seems to work nicely, but the waveform generator seems to be broken somehow. (Or I really don't understand how to set it up, but I think I tried everything, including auto-calibration). It seems to always have an output of ~+2.2V, even when it's turned off. The waveforms themselves seem to be OK, but I don't get the amplitude to exceed ~200mV.I uploaded a video of the whole thing here:https://share.mailbox.org/ajax/share/066c778800548d44614c9350548d438bbf13a65ea1f8b589/1/8/MzQ/MzQvMTM1.I learned in another post in this forum that the AWG consists of two stages:Generation stage based on a DAC902EAmplification stage based on a EL5166ISZ op-ampI have the suspicion that the AWG might have been used in a way that overloaded the op-amp and it blew, now shorting this constant offset onto the output and not amplifying the signal. I would hope the DAC is OK, since the general waveforms look good.But before I try to find a replacement for it, I was wondering if people with more experience think this is a likely scenario or if it could be something completely differentAll hints appreciated - thanks!- Jeff

author: jjedele
author_rank: Newbie
timestamp: November 05, 2022, 06:30:25 pm
content: Seems the diagnosis was correct. I replaced the opamp and it works like a charm again
DSO4254B channel 2 damaged? - Page 1
Forum section: electronics / repair

author: Betto_EEV
author_rank: Newbie
timestamp: January 19, 2021, 11:09:09 am
content: Hi everyone!I've bought this DSO and I've discovered a problem on channel 2.With ch1, ch2 and ch3 connected on 2Vpp/1kHz square wave I get on ch2 an offset [5V/div].If I decrease volt/div I no longer see the waveform on ch2. It goes off screen at the top.I have already swapped several components in this order between channel 2 and 3 but the problem remained on channel 2[see SwitchedParts.png].1. 65522. ad85103. ad83704. 3 MMBTH10 marked 3em5. PMBF4393 marked w6gI have access to the serial interface but I don't know what to check.Then I've found a difference in Offset_details.png area.Here I get:ch1 -2,379vch2 -2,328vch3 -2,373vch4 -2,362vGoing backwards from this area I arrived at a Hex inverter (?!?) And touching the L1302 inductor with the multimeter in Volt mode, the waveform goes up (offset upwards).any idea how to fix?

author: Betto_EEV
author_rank: Newbie
timestamp: January 24, 2021, 07:19:39 pm
content: when I apply a voltage across the resistance indicated by the blue arrow, the waveform lowers on the screen thus reducing the vertical offset on channel 2.This resistor is connected at the output of Hex Inverter  on top left of image.The input appears to come from an inductor that ends up on the FPGA

author: Betto_EEV
author_rank: Newbie
timestamp: January 27, 2021, 09:07:59 pm
content: I finally found the solution !!I reversed the feedback resistor between channel 2 and 3[806k on bottom left corner of IC n.3 in SwitchedParts.png].Channel 2 now has a stable signal with no oscillations.I think the problem was due to a dirty weld.Performed a correct calibration without errors (now the signal on channel 2 during the calibration was easily aligned with the other 3 channels).Hope it can help someone with a similar problem.
DSO5034A options? - Page 1
Forum section: electronics / repair

author: tkamiya
author_rank: Super Contributor
timestamp: September 20, 2020, 11:04:46 pm
content: I've recently finished repairing Agilent DSO5034A. Are there any options I can enable on this unit? Everything I see so far is for MSO variety of this series, not the lowly DSO.

author: darkstar49
author_rank: Frequent Contributor
timestamp: September 24, 2020, 08:52:14 pm
content: Quote from: tkamiya on September 20, 2020, 11:04:46 pmNo MSO option on the 5000, h/w not present... for the options, check in the test equipment forum, look after DSO6000 hack or something similar, the thread is running for ages...

author: tkamiya
author_rank: Super Contributor
timestamp: September 24, 2020, 09:44:15 pm
content: Yes, I am aware of both of the points you've raised.I said DSO because both versions exists per Agilent. I wanted to make a distinction that my scope is a DSO version not the MSO version. I'm not trying to convert one to the other.I am also aware of the thread for MSO6000. What I don't know is if any of them are applicable to DSO and 5000 series.

author: Miek
author_rank: Regular Contributor
timestamp: September 26, 2020, 03:07:47 pm
content: Yeah, all of the software unlocks (memory, triggers, decodes, segmented memory, etc.) work on the DSO5000. I used it on mine before I sold it to upgrade to the MSO. That thread is for all of the 5000/6000/7000 series - they're all very similar hardware and the 5k/6k run exactly the same firmware, so just follow the info from the thread.
DSO5072P repair, shorted digital circuit - Page 1
Forum section: electronics / repair

author: Syzeryuino
author_rank: Contributor
timestamp: July 24, 2021, 03:43:02 pm
content: i recently acquired the Hantek DSO5072P,it was sold as a non functioning unit with no refunds (it was kinda a good price in my country).after opening it up there was no power supply so after some digging someone from the thread found out you only need the digital voltage to turn the unit on, so i turned it without the analog circuit turned on, some buttons light up as shown in the picturethe display was shown as turned off but if i zoom in with my phone and turned on the lights, there's actually a bunch of linesi tried disconecting the backlight and powering it with my lab bench power supply and it showed... well a bunch of lines i guessafter some probing here and there with my limited knowledge of electronics, and the schematics, well all the voltage rails for the SMU and IC are there but still nothing but i did find out a few hotspot and a few shorted capacitor near the FPGA and ADC so not a good news.here's the shorted capacitor and it was drawing ~500mA in 3.3V railsquestion is do i need to desolder the FPGA/ADC to know which one is bad, and is it worth it? part availability seems pretty scares in aliexpress and such chinesse websitesand sorry for the English, its not my native language

author: soesante
author_rank: Contributor
timestamp: August 08, 2021, 03:21:35 pm
content: HI @SyzeryuinoSaya juga beli DSO5072 rusak. tapi ternyata ada capacitor yang lepas dan tidak tau ukurannya.apakah bisa bantu cek, mainboard bagian bawah capacitor yang hilang seperti di photo. (red marked).Terima kasih bantuannya.

author: Syzeryuino
author_rank: Contributor
timestamp: November 22, 2021, 06:01:30 am
content: harusnya si 1 capacitor copot aja gk masalah gan, kyknya si kalo liat dr schematicnya kyknya 10uf, tapi harusnya copot 1 capacitor gk bikin mati jg soalnya pararel jg. udh cek pake serial gan outputnya gmn? punya saya gk boot jadi kyknya flash memorynya mati ato firmwarenya corrupt
DSO8000 infiniium motherboard upgrade  - Page 1
Forum section: electronics / repair

author: super_electron
author_rank: Contributor
timestamp: March 27, 2022, 04:44:10 am
content: Wondering if anyone has tried upgrading intel D915gag motherboard on Agilent infiniium DSO/MSO 8000 oscilloscope ?

author: salvagedcircuitry
author_rank: Regular Contributor
timestamp: May 14, 2022, 08:59:24 pm
content: This is something I was contemplating on my dso80304b. I'll update you if/when I doEdit: dso80k is != dso8k. I missed a zero.
DSO9254A, I get an error when I start it up - Page 1
Forum section: electronics / repair

author: a390323160
author_rank: Newbie
timestamp: August 30, 2025, 01:26:20 pm
content: DSO9254A, I get an error when I start it up, does anyone know what the problem is?

author: sprit
author_rank: Regular Contributor
timestamp: August 30, 2025, 05:56:48 pm
content: hi,can you open device manager and take a screenshot?

author: a390323160
author_rank: Newbie
timestamp: August 30, 2025, 11:24:35 pm
content: open up

author: sprit
author_rank: Regular Contributor
timestamp: August 31, 2025, 04:39:06 am
content: HiYou have problem with the agilent pci card driver.First y need remove the card and try clean it, if problem still exists, re-install the os witj the backup disk.

author: a390323160
author_rank: Newbie
timestamp: August 31, 2025, 04:53:03 am
content: Recovering the disk was no use. It worked normally after replacing the faulty acquisition board. Could you tell me where the acquisition board was broken?

author: sprit
author_rank: Regular Contributor
timestamp: September 01, 2025, 01:34:17 am
content: Hello.You can upload the image to another server and attach the link in the article, the resolution will be much better.Please check this place again, this area contains the ACQ and FPGA ram, the image is quite blurry so I can't see the specific TPs.

author: a390323160
author_rank: Newbie
timestamp: September 01, 2025, 07:16:18 am
content: image libraryhttps://postimg.cc/gallery/xLc5QLQ
DSOX1102A knobs and encoder - Page 1
Forum section: electronics / repair

author: Ordinaryman1971
author_rank: Frequent Contributor
timestamp: March 17, 2022, 09:44:58 pm
content: Hi, wanted to ask if anybody knows how to get knobs for DSOX1102A scope. I've got one of those scopes from ebay some time ago and it was missing two knobs and one of the encoders was broken off.Is there a way to find a part no. from Agilent for both of those....
DSOX2014 FPGA Failured - Page 1
Forum section: electronics / repair

author: sprit
author_rank: Regular Contributor
timestamp: September 01, 2025, 03:25:06 pm
content: Hello everyone. Have a nice day.I have a DSOX2014A with a strange error. It is an FPGA Clock error. The device had a damaged nand before, I restored the OS image but when I could not reinstall the new software from the USB. The attached image shows the error after I uploaded the nk.nb0 file. I have not touched the nand yet, there is another one with the same nand error but I have solved it successfully, only this one is faulty. Is this due to the loss of clock for the FPGA? I just checked 2 quartzes but they are still fine. One is on the Asic, I still see 10MHz oscillation there and another one is next to the RTC. Has anyone encountered this case? What do you think? Thanks.

author: TinLethax
author_rank: Regular Contributor
timestamp: September 05, 2025, 01:40:04 am
content: Did you check the clock synthesizer IC next to the Xtal ?
Dsox3014a wierd error. - Page 1
Forum section: electronics / repair

author: Efefurkan
author_rank: Newbie
timestamp: April 02, 2025, 11:07:36 pm
content: HelloI have keysight dsox3014a. I get a wierd error message thatvrms greater that 5v input impedance change from 50ohm to 1Mohm to protect device channels.Remove the load from the channels before setting input impedance to 50ohm.I am getting this error while all channels unplugged. Also in 1Mohm impedance I can't see any signals on channels. I upgraded firmware to 2.66 nothing changed. Also before update I tried to make hardware test.I get failed with. Self test failed. Talon slice TrigComp.errorAlso now I have filed calibration. After update.I tried to measure if there is a voltage on channels or BNCs comes from a blow component I see 500mv on channels individually.I checked entire board amateurish I didn't see any short or voltage problem.https://files.fm/f/bkfmpsz6xv

author: Swake
author_rank: Frequent Contributor
timestamp: April 06, 2025, 09:12:05 am
content: Hi,I'm not sure I can help, but let's at least try.Quote from: Efefurkan on April 02, 2025, 11:07:36 pmDo I understand correctly that you measure a voltage on the BNC's of the Dsox3014a? Have you used another scope or a multimeter?Do I understand correctly that you read this 500mV on each of the 4 channels? This is DC voltage?Did you also measure this before the calibration?Do you have any idea how this might have happened? Was something connected to the scope?Have you verified the common things like fuses, power supplies, shorts, visibly blown components etc?
Dual Apodys Chloride Ups  Inverter Can Bus Communication Problem:: Urgent !!!! - Page 1
Forum section: electronics / repair

author: DURBUGTI
author_rank: Newbie
timestamp: July 07, 2024, 06:12:01 am
content: Can anyone has any idea as to What Timeout means in reference to Dual Parallel APODYS 18 KVA Emerson Chloride UPS.We have an alarm for" CAN Communication Problem" INVERTER TIMEOUT AND ? MARK ON DISPLAY when AC Supply breaker is energized, though the Charger is normal i.e there is no alarm.Red Led Flashing on displayNote : Its partner UPS is healthy but in shutdown positionUrgent Response is awaited.

author: coromonadalix
author_rank: Super Contributor
timestamp: July 07, 2024, 06:27:25 am
content: please do not write in capital letters it is considered yelling, you may not be appreciated

author: coromonadalix
author_rank: Super Contributor
timestamp: July 07, 2024, 02:13:13 pm
content: see an answer and a file i posted on your other thread, it may helpif not, try to contact the company

author: krishn61
author_rank: Newbie
timestamp: August 04, 2024, 12:16:02 pm
content: Hi, I am also facing the same problem. Can you share the possible solution if you have
Dual CA810 AMP Rebuild Broken Resistor - Page 1
Forum section: electronics / repair

author: vidarr
author_rank: Frequent Contributor
timestamp: March 06, 2020, 08:00:10 pm
content: A few weeks ago, I found an old amplifier for a car that has two CA810 Amp ICs. There are a few problem. The first was it was missing a pin, so I put the IC on a header, ground down the plastic package until I hit the top of the pin, then I soldered a new copper pin to the IC. It doesn't look that good, but it works like new.The next problem, I broke one of the resistors for the circuit in half removing it from a board. I am pretty sure I cannot glue this back together. It is a 1 Ohm resistor. Online, there are some ways to create resistors, but they all seem kind of 3rd world sketchy. The nichrome wire method seemed promising, but I cannot get a stable 1 Ohm resistance from it. Is there a simple way I can make this 1 Ohm resistor? A trip to the electronics store for me is a whole day event just to get there and get back home.Thanks!

author: Gyro
author_rank: Super Contributor
timestamp: March 06, 2020, 09:30:45 pm
content: Doh, you were doing well too.Nichrome would be a pain to solder. What low value resistorsdoyou have. Maybe you can make up a parallel combination to achieve 1 ohm.

author: vidarr
author_rank: Frequent Contributor
timestamp: March 06, 2020, 11:03:16 pm
content: Everything that I have on hand is on other boards. I would have to search. I was willing to spend an hour, or two, on that. I was hoping to find a simpler solution.I was also hoping to find a better circuit than the "test" circuit from the datasheet, but I have not found any alternatives.Thank you!
Dual power supply  - Page 1
Forum section: electronics / repair

author: funky2x
author_rank: Contributor
timestamp: December 24, 2023, 11:12:47 pm
content: Unaohm 40+40 volt 2.5 amp.The problem started when the fuse blown due to wrong wiring. Later, capacitors leaked and no voltage at the output. I replaced all the capacitors but unfortunately, only one channel is working now. The slave one.Any advice on identifying and fixing the problem would be greatly appreciated.

author: dobsonr741
author_rank: Frequent Contributor
timestamp: December 24, 2023, 11:30:04 pm
content: Seems to have two identical sides. Check on the voltage of C1, C2, C5 on each side. Then work forward. Check on the op-amp output.

author: coppercone2
author_rank: Super Contributor
timestamp: December 25, 2023, 07:40:28 am
content: also clean the thing, you have no idea what leaked caps ended up doing or where it got into. That thing looks dirty.

author: Swake
author_rank: Frequent Contributor
timestamp: December 25, 2023, 01:22:20 pm
content: Indeed, better to clean it out.Is it this one?UNAOHM ST-40-2500-A 2X0-40V,2.5A LABORATORY POWER SUPPLY 1982 SCH
duff lithium ion  ebike battery - Page 1
Forum section: electronics / repair

author: m3vuv
author_rank: Super Contributor
timestamp: October 05, 2020, 11:22:03 am
content: hi all,ive just brought a 12ah 13s battery secondhand,it uses groups of 3x 26650 in series,i assume each cell is 4ah,the battery only manages i would say 5 amps output at most,the voltage drops under any load,full charge measures 56v,is there an easy way to test what cells are bad cell groups measure as follows: 4.123v,4.126v,4.127v,4.127v,4.126v,4.126v,2nd string:4.121v4.121v,4.003v,4.044v,4.122v,4.121v,4.125v,any idea how to test these to see if there all bad or just a few?,cheers m3vuv.

author: Krisby
author_rank: Contributor
timestamp: October 05, 2020, 12:35:45 pm
content: Hello m3vuv,Just to get it clear in my mind, you have a 48V battery with 13 cells in series, but how many in parallel? You mentioned a cell group of six cells, and a second group of seven cells, but I don't understand the configuration. Can you please clarify how the cells in your battery are configured?Cheers,Krisby.

author: shakalnokturn
author_rank: Super Contributor
timestamp: October 05, 2020, 12:50:22 pm
content: 3P-13SThe sets down at 4.003 and 4.044V would be my first suspects of course, re-measuring voltages with some loading would give you a better idea.Try bringing the 2 low groups up to the same charge as the others with an external charger then seeing how the battery deals with a load and how fast those 2 groups droop. If they perform like the other groups it's likely the charge balancing is bad.It's also possible that only one cell of the 3 in those groups is weak, unfortunately the only way to test that is to break the parallel link.

author: Gyro
author_rank: Super Contributor
timestamp: October 05, 2020, 12:59:17 pm
content: Double post...https://www.eevblog.com/forum/renewable-energy/testing-an-ebike-battery/Make sure you're not your wasting time posting the same replies as others.

author: shakalnokturn
author_rank: Super Contributor
timestamp: October 05, 2020, 01:04:34 pm
content: Bloody double posts... F. that... Best way to get either no or too much information. Anyway I'm not going round checking.

author: m3vuv
author_rank: Super Contributor
timestamp: October 05, 2020, 02:15:35 pm
content: sorry,i made a cockup,there in groups of 6 cells,if one groupe is bad in the string will that groupe at like a big resistor blocking the current flow from the others?
Dumont / Fairchild 401B Oscilloscope repair tips ? - Page 1
Forum section: electronics / repair

author: EE-digger
author_rank: Frequent Contributor
timestamp: May 04, 2023, 03:38:06 pm
content: I got this scope a few years ago from my neighborhood pizzeria. The guy came from electronics and was cleaning his basement. Funny thing is, this is the first scope I ever owned, back in 1970.Summary:brightness goodintensity worksfocus works and decenthorizontal and vertical deflection both deflect only 5% of normal <---timebase worksy input - quiet when touch input with finger but then, deflection is way offpositionining - x position is centered about 1" from left edge of screen, only has about 1/4" adjustment rangeSince both x and y deflection are broken, I'm thinking maybe a plate voltage? Haven't worked on tubes in decades.Could be cap problems but with all systems sort of working except for deflection and positioning, maybe not.Your thoughts are greatly appreciated!

author: George Edmonds
author_rank: Frequent Contributor
timestamp: May 04, 2023, 04:27:46 pm
content: HiThat should be good fun to work on, havent repaired such a scope for about fifty years. Take care with 400VDC supply derived plate voltage.G Edmonds

author: EE-digger
author_rank: Frequent Contributor
timestamp: May 05, 2023, 03:02:08 pm
content: I found the manual with schematic at BAMA. Nice, traditional schematic on two large pages.They do have a rudimentary troubleshooting chart. The X and Y amps are almost identical. I see a +150V which they don't talk about but suspect that might be the culprit, common to both channel's symptoms.Now for the reality check. This is only for fun. The bandwidth is spec'd at 30% down at 100kc, yes, kilocycles.I recall taking a direct hit from a color CRT anode on an early color TV about that many years ago also. Most zaps today are self inflicted during ESD product testing.

author: N2IXK
author_rank: Frequent Contributor
timestamp: May 05, 2023, 03:27:27 pm
content: Had one of those scopes decades ago. Had lots of intermittent issues with the strange "surface mount" tube sockets they used on the circuit boards. Solder joints would crack, or the contacts would loosen up.
dump sunshine multimeter dt-17n  - Page 1
Forum section: electronics / repair

author: jdetawe
author_rank: Newbie
timestamp: July 25, 2025, 11:53:11 am
content: dump sunshine multimeter dt-17nsunshine dt-17n دامب أفوميترhttps://mega.nz/file/bxtGmJiT#hxQeoTtKEI8J9rpJLtk4akxn4bb_MD3BEoQrtWom-fM

author: BILLPOD
author_rank: Frequent Contributor
timestamp: July 25, 2025, 07:03:54 pm
content: Good Morning Jdetawe, Welcome to The EEVblog forum. I'm curious why your first post is a warning not to purchase the Sunshine DT-17N Multimeter. What is your grievance with this meter? Not just do you recommend not purchasing, but to 'dump' it if anyone has one. How bad is it?

author: aeg
author_rank: Regular Contributor
timestamp: July 25, 2025, 09:49:28 pm
content: He shared a dump of the multimeter's EEPROM (the link at the end of his post).

author: jdetawe
author_rank: Newbie
timestamp: July 25, 2025, 10:58:14 pm
content: Hello, brother, the device is excellent, but sometimes the EPROM IC gets damaged due to incorrect use of the device. Instead of throwing away the device, I shared a file to charge the EPROM, replace it, and bring the device back to life. The link is below the picture.
Dumpster dive Siemens Sitop 6ep1 336-3ba00-8AA0 - Page 1
Forum section: electronics / repair

author: Fenix999
author_rank: Newbie
timestamp: July 21, 2020, 12:15:53 pm
content: Hi all,My first time that I found something useful in a dumpster, I found a Siemens PSU sitop 6ep1 336-3ba00-8AA0, a 24V 20A single phase power supply.it was in the dumpster for a reason, it doesn't work, I took it apart and found a leaking capacitor, replaced it tried again and it doesn't work... not even a pip..I don't have experience repairing this kind to stuff but if some one has a schematic of the psu so I can give a try.Thanks,Ricardo

author: Haenk
author_rank: Super Contributor
timestamp: July 21, 2020, 03:23:31 pm
content: Like with all SMPSU - dangerous high voltage inside, even if switched off. Like in "life-taking dangerous". You really should be knowing what you are doing when trying to repair this stuff.

author: Fenix999
author_rank: Newbie
timestamp: July 21, 2020, 03:43:22 pm
content: Thanks for the warning.that's why I don't want to be probing around without having anything.

author: Per Hansson
author_rank: Unknown
timestamp: July 21, 2020, 05:48:11 pm
content: If one capacitor was bad then it is very likely there are more, especially of the same model/series.Caps works worse when cold, therefore heating a device can sometimes make it possible to start.Indeed I have had an identical Sitop PSU (albeit 3-phase) with this behavior. (Unit was replaced with a new one).Post some pictures of the unit and it is easier to give suggestions.
Dumpster Find Philips TV Repair - Page 1
Forum section: electronics / repair

author: ResR
author_rank: Regular Contributor
timestamp: October 14, 2020, 07:06:38 pm
content: Salvaged Philips 20PHH4109/88 (made 11/2014) stuck in boot loop. Tried replacing the caps in power supply, added few extra to unpopulated places, measured power rails, only one 1,5V rail is tuning off for a moment when it reboots. Main 12V rail is at 11,9VDC.?

author: Rasz
author_rank: Super Contributor
timestamp: October 14, 2020, 07:55:05 pm
content: easy route:write down LCD panel model, go to ebay, find $5-10 universal lcd driver board auction, message seller if your panel is compatible/can be programmed and if he has ready made cable for it.

author: limtk55
author_rank: Newbie
timestamp: October 17, 2020, 03:15:28 am
content: This is usually a software/firmware issue when it comes to endless reboot.Check the location of the eeprom chip (firmware is usually stored here) and see if you are able to find the TV's firmware online. Then you will need to flash the firmware onto a new eeprom chip (assuming your old chip is defective).eeprom programmer required (costly).Worth a shot though.
DUPLO 4X-8009 ic replace ideas  - Page 1
Forum section: electronics / repair

author: kratmel
author_rank: Newbie
timestamp: January 30, 2022, 11:37:10 pm
content: Hi, on Duplo post printing machine one of bipolar stepper driver IC DUPLO 4X-8009 burned.For long time i try to find this IC or complete board DUPLO UNIT 98H-8013. No successDUPLO 4X-8009 used for control 2A per phase stepper motor.It has 4 inputs, 4otputs (two H bridges), power supply +24V, GND and two 0.2 OHM current chopper resistor.Please help to find this IC, or any information about it control inputs, manuals ect.P.S. Now i try to replace this IC by L297+L298 curent chopper with 4 (ABCD) phase input.
Duratech TS 1560 soldering station. - Page 1
Forum section: electronics / repair

author: login
author_rank: Contributor
timestamp: June 08, 2020, 01:25:15 pm
content: looking for the value of R2. it was removed from the board at some point and went and got lost. if someone miraculously knows what it is or can steer me in the right direction to find it I would appreciate it immensely.

author: tunk
author_rank: Super Contributor
timestamp: June 08, 2020, 02:25:48 pm
content: Looks like it's in series with R1, so a guesstimate would be that they are the same.

author: login
author_rank: Contributor
timestamp: June 08, 2020, 09:36:02 pm
content: hmmm I wondered that myself since it is the same physical size as well. R1 is 150R but i would like to confirm R2 is before i put the wrong one in and release the magic smoke.

author: login
author_rank: Contributor
timestamp: June 13, 2020, 01:54:51 am
content: turns out it was. Actually had it confirmed and explained in depth at another forum but thanks for your help tunk
DVC Camera model DCN-BF5365AIN - Page 1
Forum section: electronics / repair

author: Sportline
author_rank: Newbie
timestamp: February 24, 2025, 05:47:55 pm
content: The camera was struck by lightning via the ethernet port. I found several short circuits and replaced the components (marked with a red x). I have a problem with the 100M network filter, which also seems to have been struck by lightning. The output looks fine, but I have no connection to the input. I have never had a problem with this component before, and I can't find a datasheet for it. If you can help me in any way, I would be grateful.

author: Sportline
author_rank: Newbie
timestamp: February 24, 2025, 06:41:57 pm
content: Let me add another thing, when the camera turns on, when it's dark, it switches to night mode, the IR light turns on, "but" there's no video output.
DVM9912 - Page 1
Forum section: electronics / repair

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 03, 2023, 08:48:03 am
content: Hello everyone! I cannot identify these 2 voltage regulators U4 (marking: 5A), and U5 (marking: 3A) on a VELLEMAN DVM9912 multimeter (see picture).....Can you help me?? Thanks in advance

author: SimplyElectronics
author_rank: Contributor
timestamp: December 03, 2023, 12:56:36 pm
content: Based on results from RepairCompanion, It seems they are a pair of power amps, but reverse engineering the board would confirm or deny this.https://www.repaircompanion.com/smd_code_search/5a?package=SOT89&pin_count=&manufacturer=https://www.repaircompanion.com/smd_code_search/3a?package=SOT89&pin_count=&manufacturer=

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 03, 2023, 04:30:08 pm
content: Good evening; thank you for answering me and for finding me this site that I did not know... One last detail which is outside of this post: the marking of the component 30A (SOT-89) gives: AAT60030A-S16 and I do not cannot find a supplier; Would there be an equivalent?

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 03, 2023, 04:37:26 pm
content: I have just noticed that the NJU7201U30 (SOT-89) regulator also bears the marking: 30A as for the: AAT60030A-S16; why?

author: fzabkar
author_rank: Super Contributor
timestamp: December 03, 2023, 09:15:50 pm
content: I think they could be 3.0V (3A) and 5.0V (5A) LDO regulators:https://ww1.microchip.com/downloads/en/DeviceDoc/21435F.pdf(page 11)Other possibilities:http://markingcodes.com/search/c/3ahttp://markingcodes.com/search/c/5ahttps://www.torexsemi.com/file/en/products/discontinued/-2016/31-XC62FP.pdf(page 4, also 3V/5V regulators)

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 05, 2023, 02:14:11 pm
content: Hello everyone! THANKS FOR YOUR HELP!
Dymo Labelmanager PnP Li-Ion battery dead? Replace it with 9VDC power supply - Page 1
Forum section: electronics / repair

author: amnihki
author_rank: Newbie
timestamp: August 05, 2022, 05:02:38 pm
content: Hi,Over the years I've had several Dymo Labelmanager PnP label printers, currently I have three of them connected to my office computer to support 6/9/12mm D1 tapes simultaneously. Otherwise a really neat printer, but it seems to me that whatever you do (keep it always on / disconnect it for most of time), its internal 8.4V Li-Ion battery will die within 2--3 years of use. What makes this especially aggravating is that the original Dymo replacement battery is extravagantly expensive and very few 3rd parties carry the battery and if they do, it is still quite expensive.Looks like Dymo got it wrong when they designed their USB--to--Li-Ion charger and it manages to overcharge the battery and destroy it eventually. I measured the Rint of one 2.5y old non-functional battery and it was close to 3.5ohm, so...One of my coworkers suggested to me that why do we not remove the battery altogether and replace it with a power supply...and that was what we did. :-) Basically, we took a 9VDC surplus desktop power supply, connected a 1N400x (I think 1N4007) diode in series of the plus wire (to prevent the Dymo from even trying to "charge" the power supply), and then soldered this to a pair of small probe clips that we could fit inside the battery compartment (remember, the battery itself had already been removed). All that was remaining was to make a small nick into the PnP cassette door at the rear, to make room route the power wires out of Dymo.Works perfectly, Dymo reports "100% NOT charging" all the time and prints happily ever after... I have had all three of my PnPs connected (in parallel) to one 9VDC/1A power supply for over 3 months now and I could not be happier... :-)Some day I might take a photo or two of the arrangement if anyone is interested.Cheers,Ari