hybridfree/eevblog-posts huggingface dataset:
Bosch G 800 S Generator - Page 1
Forum section: electronics / repair

author: Spanishman
author_rank: Newbie
timestamp: May 08, 2025, 11:58:37 am
content: Good morning everybody!I'm brand new to the forum!Now to the meat of the situation. I have purchased a Bosch G800S 2 stroke generator (Product nr. 7 790 400 920) from a salvage yard. It starts fine and runs butter smooth, but no output at all. Upon disasembly, I can tell that the AVR is entirely missing. My guess it pooped the pants or someone took it out for some reason. Now, I have been looking around for a replacement part, but winout a part code, I am not having any luck at all.Any chance someone could help me find a compatible part? At this point I dont discard building my own as long as I can find how to desing one at all. Thank you all for the help!
Bosch GLM150 Range-finder Display..  - Page 1
Forum section: electronics / repair

author: gamerpaddy
author_rank: Regular Contributor
timestamp: February 25, 2023, 04:15:44 pm
content: I am looking for a Bosch GLM 150 Ranger Finder Display since the one in mine broke, its not officially available from Bosch, tho you can easily replace it (no glue, just clipped in, not soldered at all.)i tried to find out how it works after not finding a replacement part for hours.its a 128x128 i2c monochrome LCD that responds ACK to the addresses 0x70 and has its pixel data (128 transmissions with 32bytes each, 4 bits per pixel) on 0x72it doesnt send any data back it just ACK's. 0x70 0x00 0x60 0x70 initiates a new frame, which is followed by 128 times 0x72 with 32 bytes of data.size is about 48x43mm active pixel area or 50x52mm outter dimensionsit has a led backlight and a 6 pin ribbon cable, chip on glass, pinout is (in no particular order) Vbat, gnd, SCL, SDA, 3.3V and backlight pwm.i wrote a program that lets me display its contents from a logic-analyzer capture to see how it talks to it. very simple protocol.i also tried to use a esp32 microcontroller as a i2c slave to react on both 0x70 and 0x72 addresses (because without ACK, the range finder just hangs and retries) but its not quite up to the task.it wont handle 2 slave addresses and the i2c sniffer just crashes the Serial port at 400khz bus speed when i let the broken displayed hooked up.it might work when i dont use the serial port and directly process the data, but its hard to debug without a debug console.Does anyone know a display that fits these specs? pinout is my problem in the end.or any other solution to this?
Bosch IXO Screwdriver - Page 1
Forum section: electronics / repair

author: TheBay
author_rank: Unknown
timestamp: November 08, 2014, 10:02:24 pm
content: Bosch IXO Screwdriver,This useful little tool broke down on me after giving it a good hammering, 3 torx bits to open, fault is with the forward and reverse switch.It's a 5 pin 3 position slide switch, I have opened it up and the contacts were toast, cleaned it up with a fibreglass pencil, half working but need to replace the switch.Daft design as all the current goes through this switch, seems to be powered by a 18650 (might uprate that while im in it)Trouble is I cannot find a 5 pin TH mount 3 pin slider switch anywhere.Found a pic of the switch, forgot to take a photo while it was out... Can't find a replacement anywhere!

author: cs.dk
author_rank: Unknown
timestamp: November 09, 2014, 10:20:37 am
content: Bosch actually have a pretty good aftermarket sparepart sales. I've orderet alot of stuff to my grinders, etc. The price is usually very reasonable.I don't know if the IXO is in the "home" or "pro" catalogue though -http://www.bosch-home.co.uk/store/spareparts/search

author: tavi_gg
author_rank: Newbie
timestamp: July 29, 2022, 08:45:14 am
content: hy! do you find the switch? i have the same problem.thx.

author: terminus
author_rank: Contributor
timestamp: August 01, 2022, 07:11:31 pm
content: I had the same issue few years ago. New IKEA bookshelf came with quick solution - tumbler switch on the wires.Still cannot find the proper switch.
Bosch MOT400 Repair OR Tips how to work without a schematic - Page 1
Forum section: electronics / repair

author: mldevw
author_rank: Contributor
timestamp: November 08, 2024, 05:19:59 pm
content: Hello,I have a MOT400 on my hands, which is an automotive ignition oscilloscope from 1985. The issue is, that it is no more switching channels and does not allow to change the sensitivity. The switching is done electrically and not with mechanical contacts as I know from my old tek 464.Do you have tips how I can work through to find such a bug without a schematic?Is it wise get an idea of what all of the components are first and then try to reconstruct the schematic?Thanks in advance.

author: mldevw
author_rank: Contributor
timestamp: November 09, 2024, 11:03:39 am
content: Hi by chance I found an oscillating NAND Gate (that should not...) that may lead me in the right direction
Bosch MUM54A00 kitchen machine - Page 1
Forum section: electronics / repair

author: roblkc3
author_rank: Contributor
timestamp: March 11, 2023, 08:24:02 pm
content: Hello!I'm actually trying to fix my wife's kitchen machine, a Bosch MUM54A00, which suddenly stopped working (one day she wanted to turn it on, but nothing happened).I'm pretty confident that I won't be able to reassemble it, since I broke 90% of the plastic clips that hold the cover together. Nonetheless, I would like to understand what's wrong with it anyway --- let's transform the bad luck in a good learning opportunity, since it's the first time I repair something that connects to voltage mains!The electronic board seems to have (by the look of it) a small power supply that converts down the 240 V to power up the small microcontroller (painted in white, looks like a PIC), and has a triac (the one with the heatsink).On an separate board there's the control logic for the knob that selects the speed that one wants the machine to operate, and a couple of connectors coming from safety switches (e.g., to ensure that the bowl is properly inserted.I've short-circuited the two pins of the bowl safety switch (after checking their behavior), and plugged the board to mains. I've then measured the voltage between the red and the blue cables that are usually plugged to the motor (as in the picture) and got 213 V.I've then plugged the mains directly to the two spade connectors of the motor, and verified that the motor happily turned.However, once I've plugged the red-blue cables of the electronic board to the motor, nothing worked anymore --- measuring the voltage on them I have 20 mV.....?What can explain this behavior?Thanks a lot in advance!Best,Rob

author: fzabkar
author_rank: Super Contributor
timestamp: March 11, 2023, 09:06:37 pm
content: Your PCB appears to have a transformerless power supply. These rely on the impedance of a series capacitor (approx. 1uF, 250VAC) to reduce the mains voltage, and this is then regulated by a zener diode.Check the DC voltage on the zener or the associated electrolytic capacitor. If the zener is not shorted, then test the 1uF (?) capacitor. It may have aged.

author: roblkc3
author_rank: Contributor
timestamp: March 12, 2023, 01:08:04 pm
content: Thanks for your reply!I've checked all the capacitors and none are shorted (though I haven't desoldered them yet to check their ESR). I had already checked them visually to verify that no electrolitic went clearly bad. Also, the diode stays at a 28 V (and the associated cap too).I haven't done any more checks since working around mains voltage makes me quite nervous (as I said, not being used to.... but still, this fear should give me a healthy dose of respect and thus possibly avoid dumb things...)Do you think that simply by having a (possibly significantly) larger ESR could lead the board to being that sensitive to having a load attached (basically, going from 213 V to 0 V)?Thanks again and have a nice day!Best,Rob
Bose 4 wires battery - Page 1
Forum section: electronics / repair

author: eduaqa
author_rank: Contributor
timestamp: October 18, 2021, 06:34:54 pm
content: I'm wondering if anybody has more information about Bose 3.7v 4 wires battery.What I knowthe wires are red (+), black (-), green (Th), white (En) ... or green and white are the up side down, don't recallAs far I know, when the system goes to ship mode, the battery cut the power (- & +), and then to rearm you need plug on the power what generated 1.6v on the enable PIn and "turn on" the battery (- & +) wireI'm wondering if someone has more information on thatAlso if someone has any diagram schematic of that
BOSE CineMate Fault - Page 1
Forum section: electronics / repair

author: IZ2KTE
author_rank: Newbie
timestamp: December 13, 2024, 09:37:29 pm
content: Hello everyone. I am new to this platform and I take this opportunity to ask for support for the repair of the "BOSE CineMate series II digital home theater system". With the fault of having turned off. I found the damage of the two optoelectronic components type CNY17 that I replaced and it started working again for about two months, after which it turned off again, but the two replaced components are efficient. Can you suggest me something or provide me with the wiring diagram.

author: rfengg
author_rank: Regular Contributor
timestamp: December 13, 2024, 10:36:06 pm
content: Welcome to the forum......attached is what I think you are looking for....The complete set of documents including service bulletins can be downloaded from :https://elektrotanya.com/bose_cinemate_gs_series-ii_sm.rar/download.html

author: IZ2KTE
author_rank: Newbie
timestamp: December 18, 2024, 09:55:06 pm
content: Thanks for the reply, I downloaded everything I needed, all very useful.
Bose Revolve SoundLink doesn‘t charge - Page 1
Forum section: electronics / repair

author: Aheld
author_rank: Regular Contributor
timestamp: December 20, 2021, 07:29:54 pm
content: Hi Forum,does anyone fixed the charging issues of Bose Revolve SoundLink speaker?I tried the Bose support steps several times by discharging, soft and hard resets and it worked for a couple of weeks.But after some weeks, the issue is back. Only the battery lamp is flashing, without charging the battery. No sound information of connecting or disconnecting power supply.Is there any hardware fix to solve this issue?Br Axel

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: December 21, 2021, 11:34:59 pm
content: Check the charger for proper output, if OK check the battery.(most likely bad)Jeff

author: abdulbadii
author_rank: Frequent Contributor
timestamp: December 22, 2021, 12:24:43 am
content: take out battery to get battery internal Resistance (BIR):clip one of its terminal/pole the easier one, together with an end of R ~2-3 Ohm and one of the MM probe correctly by use of an alligator clipthe other R end is gathered with the other one of the MM probe correctly (+ red ,- black), touch it to the other battery end and read V on MM and write down!subtract this V from the MM-read battery's Vdivide the result by this V / R whatever R is (well.: ~2-3 Ohm)so:(V batt. - V on R ) / (V on R / R)if this BIR is greater ~ 0.5 - 0.7 Ohm it's time to replaceRead otherwise the charger output current (read it when a batt end on a charger pole the other to the MM probe the other probe into other charger pole) and V, it must get degraded, V =< batt. nominam V, I < .5A and needs caps or else comp. to replace

author: Aheld
author_rank: Regular Contributor
timestamp: December 24, 2021, 08:49:51 am
content: Thank you for your replies, over Christmas should be enough time for this kind of investigation.If this issue is caused by bad batteries, I‘m wondering why it happens after approx. 2years and also with quite new devices. I would expect a design bug in Boses charger and batteriemanagement modules?And why is Bose suggesting a system reset to factory presets on its homepage?
Bose SoundLink Mini 1 Buck Converter Modification: Roadblocks - Page 1
Forum section: electronics / repair

author: MHN452
author_rank: Newbie
timestamp: July 15, 2025, 01:29:23 pm
content: Hello everyone, I'd like to inquire regarding the previous solution given by another user in another post.In short, OP bought a 12VDC to 7.5VDC buck converter, gutted the battery, then connected the output to the respective pins onto the battery base, which was then attached. The input used was the original wall plug included with the speaker, wired through the charging dock.So I bought an LM2596 buck converter with a display to set the output voltage, looks just like the image I have attached and then set it to 7.5 voltsI then wired everything just like OP did, and the speaker did actually boot up and connected to bluetooth. However, it would just shut down after about a minute of playback. I've tried it several times, also tried to factory reset it by holding the mute button, but it would still power off after about 1 minute of playback. When it powers off, I'm not able to turn it back on until I unplug and replug the whole circuit again (I'm using the original wall plug included with the speaker).Does anyone have a solution for this? A replacement battery is quite expensive for me so this seemed like a really good solution.For reference, this is the original post:https://www.eevblog.com/forum/repair/modifying-a-bose-soundlink-to-operate-without-battery/msg3034718/#msg3034718EDIT: I'd also like to add that when the circuit it plugged in butnotturned on, after the same time it would take to shut off (1 minute) the battery icon would start flashing red.
Bose Soundlink Mini 2 - Blinking red with varying PWM - Page 1
Forum section: electronics / repair

author: goaty
author_rank: Regular Contributor
timestamp: September 08, 2022, 01:07:06 pm
content: I got a Soundlink Mini 2 which is blinking red in a strange way.It starts with medium brightness, then slowly dims the blinking toward dark, then starts with full on and repeats the cycle.I checked the battery and it´s fine even under load.Behaviour is same when powered through USB or power supply connected to desoldered battery pins.(USB connection to PC is not working, only Power coming through -> No Firmware update possible)Anyone can give me a hint, what the Bose is telling me with the 'PWM' style blinking ?I can measure the signal is coming from the STM micro.Thanks, Thomas
Bose soundtouch 30 common module - Page 1
Forum section: electronics / repair

author: spd
author_rank: Contributor
timestamp: November 03, 2019, 12:08:32 pm
content: I am trying to repair a bose soundtouch 30 series iii which has no display or sound.I found service manuals for series 2 and 3 on the internet but no circuit diagram. It seems the series 3 input output board 716469-0050 is very much different from series 2. I wonder if these are interchangeable?I think the other modules (power board and input output board are OK).Has anybody ever tried to repair these and know what is the most common fault.Thanks.spd

author: spd
author_rank: Contributor
timestamp: November 03, 2019, 05:36:29 pm
content: Further my earlier message, I am able to see some voltages on the ic's though I haven't checked in detail, but there is a diode array DT1042-04TS-7 which is perhaps connected to a coil or transformer, which shows zero voltage on all its 6 terminals.The continuity also shows zero ohms in both directions, I have not taken it out of the circuit to check.Perhaps somebody here can guide me if this is how it should be.Thanks.spd
bose wave radio - Page 1
Forum section: electronics / repair

author: tekguy
author_rank: Contributor
timestamp: September 21, 2022, 05:32:31 pm
content: Hi all i have a bose wave radio,model:AWRC3G,i brought it with the cd not working,when i first plugged it in the radio came on and then the volume went to full on its own,i turned the volume down on the top buttons ok,but since unpluging it and pluging it back in to the mains,all that happens is the clock flashes but none of the buttons work,i have tested the ribbon cables from the top cover and its ok,also resoldered the the sockets for all the ribbon cables,it still just flashes the clock,any ideas also anyone know where i can find a schematic for this,and or a service manual?,cheers.
Boss DD3 guitar pedal no output repair notes - Page 1
Forum section: electronics / repair

author: fixy88
author_rank: Contributor
timestamp: October 28, 2020, 04:53:17 am
content: Boss DD3 SMD version repair notes.Symptoms: No signal from OUTPUT jack, signal present on DIRECT OUT jack. LED working when pedal switched. 50mA current draw. Signal present on input pin 2 of SMD opamp IC1 input/output but not on pin 1 output.Remedy: Replace opamp IC - SMD 4850 used. IC removed by snipping each pin while applying heat to pad on one side, then all pads heated at once on remaining side. Too tight to use hot air without a lot of kapton.
Boss RC-20XL No Signal No Output Repair Notes - Page 1
Forum section: electronics / repair

author: fixy88
author_rank: Contributor
timestamp: June 21, 2024, 01:55:20 am
content: Placing this here to help others with this repair of the Boss RC-20XL guitar loop pedal.Symptoms: No signal or very faint signal on both INST and MIC inputs.Cause: OPAMP IC12 blown. VCC/2 at 5.2v when it should be at ~4.2v.Replaced IC12 with a 4580 and unit functions as it should.
Boston Dynamics Battery Charger - Page 1
Forum section: electronics / repair

author: Poroit
author_rank: Frequent Contributor
timestamp: June 12, 2024, 05:38:43 am
content: Can anyone suggest a charger to suit the following;Boston Dynamics Li Ion Spot Battery605Wh12AH50.4VThe original charger has died and the electronics are completely potted.The battery has a 7 socket connector for charging.Two larger sockets are the battery +/-Two smaller ones have a 5V output across them maybe for feedback to the charger to indicate charge level.

author: indeterminate
author_rank: Regular Contributor
timestamp: June 12, 2024, 11:29:37 am
content: Boston DynamicsLithium iron batteries can be very dangerous when charged incorrectly.unless you are prepared to disassemble a battery pack to see what cells are used so that you now how to charge them correctlyand reverse engineer the BMS so that you can design a charger that can talk to the BMSyou are not going to have much luckIf you do decide to experiment do it outside where you are not going to burn anything down

author: 2N3055
author_rank: Super Contributor
timestamp: June 12, 2024, 02:11:26 pm
content: That is expensive robot with expensive battery. I would get replacement original charger.
Bought a new Hakko FR301 and heating element is out of alignment, needs advice.  - Page 1
Forum section: electronics / repair

author: electronic_guy
author_rank: Regular Contributor
timestamp: August 13, 2022, 05:02:03 am
content: Hi,I bought a new Hakko FR301 desoldering tool from Amazon. When I received it I noticed that the heating element is out of alignment where it meets the filter pipe. I have included a picture of it. Have you noticed this error in your Hakko FR301 ? I'm beginning to thing it's a cosmetic defect. But still thinking if I should return it and ask for new one. Perfectionism keeps nagging meI checked the working of the unit and seems there is no problem in sucking, though I have no way to check if its efficient as it should be.Please check your Hakko FR301 and let me know if there is this misalignment as it came.Thank you.

author: wn1fju
author_rank: Frequent Contributor
timestamp: August 13, 2022, 11:47:26 am
content: I looked at my FR301 and it looks exactly like yours - slightly out of alignment. Never noticed that before! Anyway, I stuck a screwdriver in there and gently moved it back to center. As you have experienced, I never had any problem with the functionality of the desolderer.Normally I would suspect Amazon as a lot of things bought from them are counterfeit or damaged seconds or returns. But I bought my FR301 directly from an authorized dealer, so I guess it's not an Amazon "thing" in this case.

author: electronic_guy
author_rank: Regular Contributor
timestamp: August 13, 2022, 01:45:46 pm
content: @wn1fju Thank you for the clarification on this.I've heard of those counterfeit problem on Amazon when I bought the FX888 from Amazon. It's risky, but they seem to have lower prices. may be that's how they have lower prices in the first place.
Bourns pots, vertical vs horizontal - Page 1
Forum section: electronics / repair

author: Audiorepair
author_rank: Frequent Contributor
timestamp: January 19, 2023, 10:33:35 am
content: OK, so I ordered some Bourns pots, this one.https://uk.farnell.com/bourns/prs14r-20022-503b1/rotary-potentiometer-50kohm-0/dp/3758700Datasheet here:https://www.mouser.co.uk/datasheet/2/54/Bourns_03312021_PRS14R_datasheet-2298288.pdf(there is no datasheet link on the Farnell site)Page 2 on the datasheet shows the How to Order code construction below the diagrams of the vertical style vs horizontal style.The order coder is PRS14R-20022 meaning it should be a vertical version, as in the picture on the Farnell site.Only I received the horizontal version which would have the code PRS14-40022.Now weirdly, I'd also ordered some Bourns datapots.https://uk.farnell.com/bourns/pec12r-4220f-s0024/incremental-encoder-2ch-100rpm/dp/2663532The datasheet for this appears to have the opposite definitions of Vertical and Horizontal.https://www.mouser.co.uk/datasheet/2/54/PEC12R-777795.pdfThe part I received is as in the picture, what I call Vertical, in that you push down towards the PCB to operate the switch.Yet Bourns call this Horizontal in their datasheet, the opposite of what they do in the analogue pot datasheet.Am I missing something?

author: DavidKo
author_rank: Frequent Contributor
timestamp: January 19, 2023, 11:00:17 am
content: Based what I see in the datasheetPRS14R-2xxxx-xxxxx have vertical pins and the photo is wrong. In the photo I see PRS14R-4xxxx-xxxxx from datasheet.

author: Audiorepair
author_rank: Frequent Contributor
timestamp: January 19, 2023, 11:20:39 am
content: Quote from: DavidKo on January 19, 2023, 11:00:17 amOK, I see the 4 horizontal/vertical diagrams above the How to Order panel that indicate that the photo is a vertical type, which should be PRS14R-2xxx-xxxx, the photo is right?

author: DavidKo
author_rank: Frequent Contributor
timestamp: January 19, 2023, 11:27:59 am
content: Look in "Product dimensions" not "Shaft & Bushing Dimensions". It is previous page. But I must say I was also confused at the first lookEdit: in "Shaft & Bushing Dimensions" are pins clearly horizontal in "vertical" column

author: Audiorepair
author_rank: Frequent Contributor
timestamp: January 19, 2023, 11:41:04 am
content: Quote from: DavidKo on January 19, 2023, 11:27:59 amAh, now I get it. One style they are saying has a vertical bush yet horizontal pins, the other has a horizontal bush yet vertical pins.So there is no overall definition that a part is "Vertical" or "Horizontal" then, it depends what bits you are referring too.That's just f**king great.Thanks for clearing that up!
BP Microsystem CP-1128  - Page 1
Forum section: electronics / repair

author: tim_bo
author_rank: Newbie
timestamp: April 24, 2023, 05:12:34 am
content: Hello everybody and thanks a lot that I was able to join this great forum!I bought the CP-1128 from BP Microsystem as in "good condition" with the original box and original accessior.After some usage on EPROM's I wanted to program some GAL's and recognized some issues with the programmer: I was not able to program any of them.Used Software: bpwsoft-03 on a Windows98se system.The result of the self hardware diagnostic programm is as follows:*************************************************************Port=278, Model=CP-1128, Revision 1.06 pcb REV.G 28 pins 8.0MHz 50 27 13,Communications self test:0/10000 Passed test.Executing Timing test:Passed test.Testing Pin Drivers:Pin 4: in HI-Z mode H->Z is set to 0.0 but is 25.1.at QH: is set to 3.4 but is 3.3.Testing VCC bypass:Pin 28 24 20 18 16Testing independence of pin drivers:Testing current sinks:Test complete. 2 errors detected.Command failed.*************************************************************Disabling the continuity checkbox leads to a success, but can I trust the programmer anymore ?Does anyone have experiencies with this programmer ?I can not interprete this results now, so i wanted to ask here. Maybe there is someone who can help me?BR

author: m k
author_rank: Super Contributor
timestamp: April 27, 2023, 04:31:36 pm
content: One pin driver seems to be stuck.What disabling the continuity checkbox means?

author: tim_bo
author_rank: Newbie
timestamp: May 02, 2023, 12:44:02 pm
content: Hi! Yes I know.I am step further, because I desoldered the group of IC's around pin 4 and tested them with an IC tester.One latch of a 74HCT259 is not working properly.Tomorrow I'll get a new one than i can tell you more. Hope that was all.Disabling the continuity check means, that the programmer does not check every (bond) connection to the die (inner core) of the IC and start the program routine directly.BR

author: m k
author_rank: Super Contributor
timestamp: May 02, 2023, 06:35:33 pm
content: If we assume that 25.1 is a voltage and pin 4 is the actual pin number you definitely want all possible tests before actual programming.Putting 25V to I/O pin is not necessarily very healthy.

author: tim_bo
author_rank: Newbie
timestamp: May 12, 2023, 07:08:19 pm
content: Update:On further tests, I recognized abnormal high temperatures on the pindrivers (especially the MOSFETs and the right culumn of small plastic Transistors).But none of the semiconductor which belongs to the pindriver 1-8 were damaged.The fault was a broken resistor network (SIL 9-8 5.6k) next to the heavy transformerAfter replacing the broken part the programmer works perfekt again.
BP190 Battery for fluke 196 - Page 1
Forum section: electronics / repair

author: Rollin Hand
author_rank: Regular Contributor
timestamp: September 25, 2019, 02:42:19 pm
content: Can you recommend a good battery for this meter ?Got 2 from epay and only lasted 3 monthsA replacement with 2 16850 will work ? for how much time.Thanks

author: mr.fabe
author_rank: Regular Contributor
timestamp: September 25, 2019, 05:10:24 pm
content: Quote from: Rollin Hand on September 25, 2019, 02:42:19 pmDid you contact the seller? Some sellers offer up to a 1 year warranty. At least mine does.https://www.ebay.com/itm/3600mAh-BP190-Battery-for-Fluke-ScopeMeter-192-192B-196-196B-196C-199-199B-199C/262592576098?hash=item3d23bcba62:g:SeQAAOSw9NdXvgXGI wouldn't recommend using Li-Ion batteries unless you are prepared to build a new charging circuit. The unit requires NiMH type batteries only.You can also rebuild your pack.

author: nenea dani
author_rank: Regular Contributor
timestamp: September 28, 2019, 04:29:49 pm
content: I do not know if it is related to your case but there is a service bulletin for 196 in which a defect is treated for frequent battery discharge. It looks like a transistor enters s.c. It's a disease with batteries at this scope.

author: cozza
author_rank: Regular Contributor
timestamp: October 01, 2019, 08:30:53 pm
content: "I do not know if it is related to your case but there is a service bulletin for 196 in which a defect is treated for frequent battery discharge. It looks like a transistor enters s.c. It's a disease with batteries at this scope."Do you have any more information on this, as my Fluke 196 goes flat if not left plugged in, which is annoying....

author: Fabry_85
author_rank: Newbie
timestamp: May 21, 2020, 04:42:25 pm
content: hi everyone, i have a problem with my fluke 196c.Since yesterday it no longer lights up.pushing the power button you will hear a beep and the screen will remain black.I unplugged the battery and it does the same.19.5vdc comes out of the power supply.help me.
BPS-305 - Page 1
Forum section: electronics / repair

author: lionelkjh
author_rank: Frequent Contributor
timestamp: April 20, 2022, 03:05:44 pm
content: Hello everyone! I am looking for the value of the potentiometers for a BPS-305 laboratory power supply whose marks are: VR102, VR104, VR101, VR305. Thank you for your valuable information
bq20z955 Data Flash Image - Page 1
Forum section: electronics / repair

author: Denkawa
author_rank: Newbie
timestamp: March 28, 2025, 12:12:01 am
content: Hello everyone,I have an Acer Aspire with an AS07B61 battery. This battery is no longer working, so I disassembled it and discovered that it consists of six 18650 cells. I tried replacing them, but the BMS detects that they are not the original ones and goes into lock mode.I then thought about resetting the chip values so that it would accept the new cells. The chip is a bq20z955, so I tried accessing it using an EV2400 and bqStudio, but it is not recognized.Can anyone help me? How can I reset the values? I suspect that it doesn't appear in the list because it is encrypted and that I need a data flash to decrypt the chip, correct?I'd appreciate any help. Thanks in advance!Cheers,Denis

author: asis
author_rank: Frequent Contributor
timestamp: March 30, 2025, 07:42:46 am
content: Hi,Most BMS have one major vulnerability, the essence of which is that if you do not use the battery for a long time, the voltage will completely dry up and the moment will come when the controller itself (BQ) will go out.This happens even with new products that are lying in the warehouse unsold.In this case, it will be almost impossible to wake up the controller itself without opening the battery pack, which is what you actually did.In practice, it is enough to charge the batteries from a laboratory source, and to turn on the existing BQ, you need to briefly short-circuit the + battery pack with the positive terminal of the controller itself Vcc (BQ).Also check the condition of the chemical fuse.As a result, the controller will open the MOSFET's and provide the opportunity for communication via SMB.If this happens, you can try to charge the battery using standard means (or via LAB PSU).If the controller is locked and has blown the fuse, you are unlikely to be able to find the password to unlock it.-If you changed the batteries yourself, you probably de-energized the controller - keep this in mind.-In bqStudio, both in old and new versions, I did not see the bq20z955 chip in the list of supported ones.By brute force, you can try to find BQ from the bqStudio list, in which EV2400 will issue a replica.

author: Denkawa
author_rank: Newbie
timestamp: March 30, 2025, 04:19:48 pm
content: Hi, thank you for your response. I forgot to mention that the cells were at 0V and unrecoverable, so I couldn't charge them 'manually.' Now that I’ve installed the new cells, when I connect the battery to the PC, it shows the battery at 100%, but measuring the output pins gives 0V—in fact, as soon as I unplug the charger, the PC shuts down. Because of this, I think the chip is blocking the output. Do you have any advice to get this battery working again?
Braking Of Asynchronous Motor "Mafell Erika 70" - Page 1
Forum section: electronics / repair

author: KaiOwei
author_rank: Newbie
timestamp: October 01, 2019, 02:17:26 pm
content: Hello,I recently got a used Table Saw wich was built in 1990. It works perfectly fine, but the braking when turning it off doesn't seem to work at all.I attached pictures of the board.All components look visibly fine and i replaced the Thyristor, wich didn't fix it.

author: Andy Watson
author_rank: Super Contributor
timestamp: October 01, 2019, 03:30:10 pm
content: What testing facilities/tools do you have available ?Have you checked the two fuses? The solder joints for the diode (see photo) look dodgy - this might indicate that the diode has been over heating.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 01, 2019, 03:40:21 pm
content: It it not breaking at all, or just too short. One could do a test without the blade and maybe also the flange. In this case a short breaking phase would still noticeable. The trimmer should be there to adjust the time - so the actual setting is not super critical and one could note the position and more it back and forth. Another possible failure point is a Diac (often looks like a diode) at the thyristor gate - these sometimes fail and no longer trigger.Checking the 2 electrolytic caps could also be worth a try.

author: KaiOwei
author_rank: Newbie
timestamp: October 01, 2019, 05:01:36 pm
content: I found out that the 68kOhm resistor next to the potentiometer was broken and had a value of Infinity.Also replaced both electrolyte capacitors.When i plugged in the AC connector, the Motor was humming a little, as if the brake was on.I pulled the Plug and after connecting it again, it didn't make a sound, but the brake also didn't work.Edit: I found a post on a German forum wich has the same circuit and a description of all parts.
Brand New Rigol DHO914 not starting up and screen never turn on - Page 1
Forum section: electronics / repair

author: tinashe
author_rank: Newbie
timestamp: January 20, 2025, 11:43:40 am
content: I recently bought a Rigol dho914 oscilloscope. When I turn it on, the keypad backlight turns on for a second and then shuts down. The screen is never turning on. However, I kept on turning it on and off as instructed in the manual, and at one point, it was able to boot, and the screen was on, but after a few seconds, the screen just turned off again, and ever since then, it never turned on. Can someone help me how I can resolve this.

author: NE666
author_rank: Frequent Contributor
timestamp: January 20, 2025, 04:22:01 pm
content: If it's brand new, then make sure you've registered the warranty online and then contact Rigol's technical support. If you purchased from an authorised distributor there is also a good chance that they may be able to help, or depending upon how long ago your purchased it and contract law in your region, they may be liable to just replace it.There's little to nothing else you can do, not without voiding the warranty.

author: tinashe
author_rank: Newbie
timestamp: January 21, 2025, 01:09:48 pm
content: Thank you. I continued turning it on and off. Today, it was finally able to boot. After that, I updated the firmware. The it went back into the same cycle again. Then, after some hours of trying it it started running normally. Now I have been monitoring for five hours and it is still working.
Brand new to the hobby and got a Tektronix 535, severe low voltage power rails - Page 1
Forum section: electronics / repair

author: Tekrat
author_rank: Newbie
timestamp: July 30, 2025, 02:21:53 am
content: Let me start this off by saying I'm extremely new to tube equipment, and electronics device repair in general. I recently picked up a tektronix 545A and once I got that beauty home I got hooked and bought another 535. Because the 535 has a simpler vertical amplifier I decided to fix it first. I started by replacing all the electrolytic capacitors (whole device)+ bumblebee caps in the low voltage section. Once powered on the scope never clicked and I measured the power rails as follows-150v is at 5v(yes positive)100 is at 84v225 is 25v350 is 38v500 is 237v-150v starts 8kohm settles to 3.6kohm100v 0.33kohm225v 7kohm350v 100kohm500v 3.3mohmSuper bad, I also checked to make sure that the -150v on the transformer was actually good and thankfully it's outputting full 200v ac just like the wiring diagram shows. Probing around wherever -150v is it all reads the same 5v. I wanted to try and completely disconnect the load from the 150 line but couldn't figure that out.I decided to shuffle the tubes around in case there was a bad tube in the -150 or 100v area or at least try to change something. In that process I found V765 is blown, tube was cracked at the base but don't have a replacement.Anyway for the past week I've been trying to figure this out by myself. I've triple checked all my caps have the right polarity (I did have one backwards, C471) and everything got attached correctly (and reference other users pictures to try and verify) but I wouldn't be surprised if I still messed something else up Hopefully someone can help guide me in the right direction to figure this out as I've gotten no where.Serial number is 548 with modification m-0170 (guessing the replacement of the selenium rectifier with diodes)before anything was touched the scope did power on but didn't display anything correctly and had a couple power rails low (don't remember which). One capacitor can boiled (C790) when I was testing.

author: Tekrat
author_rank: Newbie
timestamp: July 30, 2025, 10:28:33 pm
content: Figured it out, didn't realize the there was a time delay relay to warm the tubes up. Turns out the delay tube is bad. Problem solved.

author: MathWizard
author_rank: Super Contributor
timestamp: August 01, 2025, 08:05:04 am
content: Yeah IDK what to make of those voltages, hopefully there's no shorted windings in the transformer. I see a ton of those old brown carbon resistors, they are known to drift a lot. And I think they use Silver laced solder on those joints too.I have an old Tektronix scope, it doesn't have tubes, but it sure looks cool inside. I'm in no rush to restore that yet, more things to learn first before I go messing with CRT voltages.
Breadcrumb for Agilent E4418B repair / Power button not working - Page 1
Forum section: electronics / repair

author: codex0
author_rank: Newbie
timestamp: February 16, 2021, 10:59:37 pm
content: There are a number of threads detailing issues with the front membranes on these, many people end up ordering replacements from China because the real deal from Agilent is so expensive.My unit would not turn on or off via the power button - always in standby.A few users mentioned here and on the Agilent group that checking the battery is important on these - mine was dead.Behavior with a dead (or missing) battery is the unit will turn on, but once you turn it off it will not turn on again (until unplugged/drained). These batteries are really difficult to remove because they are siliconed on, so I pried off the solder tabs before removing the battery then desoldering each tab. I bought a replacement with installed wires and used a zip tie to fasten it so it would be easy to replace in the future (the manual suggests every 3 years).Replacing my battery did nothing to fix this issue - removing it made things slightly better. - when I plugged it in with the battery detached via the battery jumper it would immediately turn on, then it would turn off happily once with the power button then not turn back on again.I measured resistance across the power button pins (If you are facing the front of the instrument from the top, they are pins 5 and 6 counting FROM THE RIGHT to the left). 2MOhms open and about 70 ohms closed.Based on other threads I was afraid I had a bad front membrane and would need to replace it. On a whim, I removed the keyboard flex cable where it plugged into the mainboard and cleaned the contact areas with alcohol (gently). A noticeable amount of carbon came off. Everything now works as it should.I'm leaving this as a breadcrumb / thing to try before ordering a replacement membrane.

author: nfmax
author_rank: Super Contributor
timestamp: February 07, 2022, 10:44:29 am
content: Thanks for this post, it gave me some vital clues to fixing my instrument:https://www.eevblog.com/forum/repair/(mended)-ep4418b-power-meter-doesnt-turn-on/new/#new
Breaking News, California Right to Repair Passes Assebly 09/12/2023 - Page 1
Forum section: electronics / repair

author: KG7AMV
author_rank: Frequent Contributor
timestamp: September 13, 2023, 02:18:42 am
content: Just in California Right to Repair Passes Assembly 50-0 09/12/2023 on to the Governor for a Signature.
Breville BOV800XL dim backlight and button repair - Page 1
Forum section: electronics / repair

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 28, 2020, 03:49:35 pm
content: I should have started this topic with the model so people can find it...The backlight can be brought back to life with 4 Kingbright APT1608LVBC/D blue LEDs. It's fiddly but worth it, it looks new.The pushbuttons becoming very hard to register a push is solved by replacing them with Schurter 1301.9302 tactile switches.The rotary dials becoming fiddly is solved by spraying a small amount of Nu-trol control cleaner into the switches.Not electronics related but the door spring can be replaced with a generic tension spring as found in this kithttps://www.dormanproducts.com/p-7784-59001.aspxUse the second strongest one but make a 1 inch long extension otherwise the door is far too strong. It will slam into next week without an extender... If you use a weaker one the door won't be able to push the rack back in.Another item rescued from the trash. And now to toast some English muffins!

author: Squoip
author_rank: Contributor
timestamp: October 31, 2020, 12:51:46 am
content: Breville makes some nice equipment. I own that oven as well as some other Breville stuff. Luck you to have gotten one for (I assume) almost free.
Bricked Voltcraft DSO-1202D - Page 1
Forum section: electronics / repair

author: rugo100
author_rank: Contributor
timestamp: December 02, 2024, 08:19:24 pm
content: my Voltcraft DSO-1202D is booting but then does not responding for button pressing.To do firmvare update over Utility menu is impossible since the interface hardly works (menu just appear if button is pushed and hold for a few seconds then the selected menu usually disappear almost immediately. So to select a menu command is very hard, seems to be impossible.Over on UART connection can see LINUX shell is working and even DSO is starting.Based on an old message (2018) of user "Corlumbus"https://www.eevblog.com/forum/repair/voltcraft-dso-1102d/I have tried to manually update the system.Steps I have done:1. I have connected to the DSO over a USB serial IFC (FTDI Care about 3.3V settings!)2. I downloaded the latest firmware (DSO5202B) from Hantekhttp://www.hantek.com/en/ProductDetail_3.html3. Unzipped the downloaded "DSO5202B_Firmware.zip" file and got"dso5kb_func_dso5202b20180226.up" file4. decrypted the up file: gpg -o dso5102B.tar.gz -d dso5kb_func_dso5102b20180226.upwhich result was "dso5202B.tar.gz" file5. with WinRAR unpacket the "dso5202B.tar.gz" file and its result was: "dso5kb_func_dso5202b20190818.up.tar"6. and from this .tar file with WInRAR I got the "tekwayup_client" folder with content and the the "upend" text file7. I copied "tekwayup_client" and "upend" to an USB stick (<= 4 GB and FAT32)8. I connected to the DSO with a term emu program (115200bps) and switched on the DSO9. on terminal screen linux boot log displayed and started the DSO (initialization and many parameter settings were seen)10. after pressing an enter on terminal I got the linux prompt then11. copied the directory tekwayup_client to /tmp/ : cp -R /mnt/udisk/tekwayup_client /tmp12. set permissions: chmod 777 /tmp/tekwayup_client/packet/do_update.sh13. then run the update: /tmp/tekwayup_client/packet/do_update.sh14. then run sync command: syncUnfortunately after restart of my scope nothing changed. Still no response after booting.What else can be try to unbrick the device?Any help, advice, suggestions would be greatly appreciated.Thank you

author: rugo100
author_rank: Contributor
timestamp: December 02, 2024, 08:25:24 pm
content: if you are looking for the UART pins on Voltcraft DSO-1202D take a look on attached pic.
Bridge Rectifier  - Page 1
Forum section: electronics / repair

author: WelderCrafts
author_rank: Newbie
timestamp: October 10, 2021, 04:31:34 pm
content: Hello allI've got a bridge Rectifier for a Welder that has 24 diodes and about 6 or 7 of them are fried.I've tried finding replacements but can't seem to find the same ones.The diodes are marked TV 256RCould I possibly replace them with a stud type diode? If so what value diode would I need? Or could anyone suggest an equivalent?The welder itself is a 1 phase 120amp MIGThanks

author: fzabkar
author_rank: Super Contributor
timestamp: October 10, 2021, 05:34:11 pm
content: Alternator diodes are usually press-fit types. Be aware that they have two different polarities.

author: WelderCrafts
author_rank: Newbie
timestamp: October 10, 2021, 06:18:03 pm
content: thanks shall check them out

author: bdivi
author_rank: Regular Contributor
timestamp: October 11, 2021, 08:23:17 pm
content: Few years ago I made a 150A welder and used 4xKBPC5010 in parallel. Still kicking to this day.This is probably more reliable and cheaper. Just make sure you buy original products and not fakes.

author: WelderCrafts
author_rank: Newbie
timestamp: October 11, 2021, 09:19:06 pm
content: I ordered one of these will see if it works￡6.76 22%OFF | MDQ 150A-1600V Black Single-Phase Diode Bridge Rectifier 150A Amp High Power 1600Vhttps://a.aliexpress.com/_mNyG2du
Bridge rectifier replacement options - Page 1
Forum section: electronics / repair

author: kasumyku
author_rank: Regular Contributor
timestamp: February 01, 2020, 11:42:25 pm
content: Hi everyone,I’m trying to repair a 15V 2A variable DC power supply.The bridge rectifier overheated and blown so I was wondering if I can replace it with a different rectifier because it looks like this power supply was built with whatever parts were availableThe one used is KBP210 (see pic), I’ve also attached data sheet.Thanks!

author: cowasaki
author_rank: Frequent Contributor
timestamp: February 02, 2020, 12:38:18 am
content: As long as the power handling is the same or higher you just need something that will fit physically and have the same pinout . That is a pretty standard device.

author: gbaddeley
author_rank: Regular Contributor
timestamp: February 04, 2020, 09:50:09 am
content: Agree, I would go for at least a 100 PIV rated at least 5 - 10 A to give a good overload margin. Bridges are cheap, so don’t scrimp.
Bridgeport R2E4 CNC Mill - Replacement IC - Page 1
Forum section: electronics / repair

author: gdgarris
author_rank: Newbie
timestamp: July 31, 2023, 04:11:00 am
content: Hi all,I recently acquired a Bridgeport R2E4 (circa 1984) CNC milling machine. I powered up the machine in my garage, jogged the table around a bit, I was greeted with a drive fault. After poking around in the cabinet for a couple days, it appears I have lost the 15V supply on the DPS board. The IC that is responsible for generating this supply (i.e. LAS6380) has not been manufactured for many, many moons, and the few sources I have found are fairly pricey. Two questions:1. Any suggestions on where I may find a vintage IC like this? I have found one on eBay, but I am a little worried I may smoke a second one and at $70 a pop, that stings a bit.2. Any options on retrofitting something similar that do not require any drastic modifications to the board?Links:LAS6380 Datasheet:https://pdf1.alldatasheet.com/datasheet-pdf/view/148595/ETC1/LAS6380.htmlMill Manual (DPS, page 59):http://manuals.chudov.com/Bridgeport/R2E4-Boss-Manual-Lloyd.pdf

author: edavid
author_rank: Super Contributor
timestamp: July 31, 2023, 04:15:29 am
content: Can you just hook up an external 15V power supply? Do you know the current requirement?

author: gdgarris
author_rank: Newbie
timestamp: July 31, 2023, 04:48:19 am
content: Honestly, I hadn't even though about using an external supply. Current requirement would be no more than 8 amps, that is what the original IC is rated for at least.I'll still probably purchase an original IC and repair the board eventually, unless anyone as an alternate suggestion, but the external supply would keep me from smoking several with I sorted out any additional gremlins.Thank you very much!