hybridfree/eevblog-posts huggingface dataset:
Is this Weller soldering pencil worth repairing / getting a new one? - Page 1
Forum section: electronics / repair

author: forumate
author_rank: Contributor
timestamp: August 20, 2022, 07:37:14 pm
content: I found a Weller WTCPN station but one of the pins on the pencil broke.However I am not sure it's worth trying to fix the plug or get an entirely new iron pencil at all because someone threw this station to the garbage so maybe there's a problem with the station itself?This is the insides of the station (One of the cables seem to have been bent there for a long time, I marked it with red).The station itself turns on, and the iron pencil did get hot before the pin broke.Photos:https://imgur.com/a/kCstc6cTy!

author: floobydust
author_rank: Super Contributor
timestamp: August 20, 2022, 08:10:10 pm
content: I'd repair it, I find this Weller has really good heat for general purpose soldering, compared to Hakko FX888 and chinese T12 clones.The bent white wire is OK, you can check continuity at the mains cord, on Ohms with the power switch on.Also, on the pencil see if there is continuity across the heater and magnestat switch. Just to get an idea of repair costs/parts etc.One problem I see is lack of a primary fuse, if it was mine I would add one. I have WTCPN that came with such a fuse and it's vintage late 1990's.

author: forumate
author_rank: Contributor
timestamp: August 20, 2022, 08:22:02 pm
content: thanks! I tried looking up repair parts or even the entire TC201 soldering iron and couldn't find. I also understand that they don't see this proprietary plug separatelyThere is this fuse soldered to the pin - that's not the main fuse?

author: floobydust
author_rank: Super Contributor
timestamp: August 22, 2022, 07:02:39 am
content: The transformer's 24VAC output is from the red wires, going to the fuse. This protects against shorts in the handle and cable.But it does not give coverage if the power transformer shorts. Later models added a mains fuse, but new models i.e. WE1010A they took it out againIs this what you are looking for?https://www.newark.com/weller/pl120/replacement-plug-receptacle/dp/52F5674USA socket pins are likely Amp/Tyco/TE Electronics part number207437-3

author: precaud
author_rank: Frequent Contributor
timestamp: August 22, 2022, 01:36:48 pm
content: Quote from: floobydust on August 20, 2022, 08:10:10 pmAgreed. My WTCPN has been in daily use since the mid-80's and I've only had to replace the heater once.
ISO-TECH IPS 303D PSU schematic sought  - Page 1
Forum section: electronics / repair

author: aztecboy
author_rank: Contributor
timestamp: November 10, 2021, 11:01:22 am
content: Desperately seeking the schematic for an old ISO-TECH IPS 303D PSU (0-30, 3A)This is the one with a monochrome display.Mine sadly has gone u/s after many years of service.
ISO-TECH isr-2102 documantation required - Page 1
Forum section: electronics / repair

author: pcmad
author_rank: Regular Contributor
timestamp: May 10, 2023, 09:58:42 pm
content: Hello does anyone have any documentation for ISO-TECH isr-2102 oscilloscope 100 mhz thank you in advance

author: MathWizard
author_rank: Super Contributor
timestamp: May 14, 2023, 12:15:45 am
content: It's pretty hard to find sch.'s for anything new. Does it have some problem ? Plenty of people on here know how to fix modern ones though.

author: DavidAlfa
author_rank: Super Contributor
timestamp: May 14, 2023, 12:39:54 am
content: Maybe a rebranded Tektronix ?

author: picburner
author_rank: Frequent Contributor
timestamp: May 14, 2023, 06:31:02 am
content: The real manufacturer should be GW-Instek (GOS-6103). Of the latter I found the user manual only.Your version does not have memory.

author: picburner
author_rank: Frequent Contributor
timestamp: May 14, 2023, 06:54:42 am
content: I found the exact model: GOS-6112. The user manual of this is also found on the net.Hereyou can find the service manual too.

author: pcmad
author_rank: Regular Contributor
timestamp: October 19, 2023, 12:01:33 am
content: thank you for your responce after digging around iso tek is a rs brand a rebage of GW-Instek (GOS-6112) also GW-Instek scopes are rebranded left right and centre see attached documents i acquired main from rs components themselfs
ISO Zero Ohm Knob for Beckman Tech 360 DMM - Page 1
Forum section: electronics / repair

author: Beckman Tech 360 Fan
author_rank: Newbie
timestamp: August 09, 2024, 06:05:50 am
content: Wanted: Zero Ohm Knob Beckman Industries Tech 360. Thank you

author: floobydust
author_rank: Super Contributor
timestamp: August 10, 2024, 01:30:53 am
content: Welcome to the forumsThese three images I took from an eBay ad for the service manual, but I lost out on the bid and not sure who has it now. People should just scan and post this stuff.I have the Tech 360 manual scanned w/schematic but did not find a way to make it a multipage PDF. I think the 350 verses 360 schematic label is swapped in the manual. I forgot, it's been a while since I was into these. They are a great multimeter for doing service, the 20Ω range has 4mA test current which is unique.I have some parts like that knob and Allen-Bradley potentiometer 3000-090-108? 5MEG? and the plastic mount. Would trade for a LCD front bezel.I'm in the stupid Beckman multimeter LCD rot and zebra strip drama, it's the main weakness with these, as I have a few to repair. Made in USA baby.

author: Beckman Tech 360 Fan
author_rank: Newbie
timestamp: August 10, 2024, 03:54:37 am
content: Hello floobydust. Thank you for all the great information. Unfortunately I have nothing to trade with because this is my personal Beckman TECH 360 DMM that I saved up money from mowing grass to buy 42 years ago May 1982. Would you be willing to sell me a Zero Ohm knob? Or can you tell me where I can buy one? Thank you floobydust

author: floobydust
author_rank: Super Contributor
timestamp: August 10, 2024, 05:48:54 am
content: I couldn't afford one back then. I think I earned $3.50/hour wage in the repair shop.Retail $289 1981 sold for $269 is $850 today. The TECH 310 was around $140 or $450 in today's dollars.Flukes were going for similar price, so Beckman was up their in price for this model.How about that 12,000 hour battery life? And room for a beer inside lol.PM sent.
Isopropyl rubbing alcohol vs Propanol-1 - Page 1
Forum section: electronics / repair

author: JizyahCollector
author_rank: Newbie
timestamp: May 01, 2023, 11:11:20 am
content: Hello, hope you guys are doing well, I need to clean some electronic components (mainly an ESP32 module and removing old thermal paste from my i3-3110m processor in order to repaste it for some preventative maintenance), I don't have access to Isopropyl rubbing alcohol where I live but I did manage to find however some Propanol-1 that appears to be 99%, was wondering if I could use it for my aforementionned purposes and not damage my components, I read online that they are similar but I'm no chemistry expert so I am not sure yet. Some help would be hugely appreciated!

author: JohanH
author_rank: Frequent Contributor
timestamp: May 01, 2023, 12:10:41 pm
content: I'm not a chemist either, but it looks like propanol-1 isn't used much for cleaning. It has some acidic characteristics that sounds like not a good thing. It's also more harmful than isopropyl that is more commonly used. So don't get it in your eyes. But for cleaning thermal paste from a metal surface you can use almost anything. I.e. rubbing with a moist paper towel and it doesn't matter if it isn't completely clean. If it's a thermal adhesive tape I suggest mechanical cleaning first e.g. with a knife or spatula.

author: tooki
author_rank: Super Contributor
timestamp: May 01, 2023, 12:28:18 pm
content: I think I’ve seen flux removers that use propan-1-ol as an ingredient (alongside isopropyl and other stuff), so it’s probably safe.

author: JizyahCollector
author_rank: Newbie
timestamp: May 01, 2023, 01:22:49 pm
content: Will it be fine with the conformal coating on PCBs?

author: jpanhalt
author_rank: Super Contributor
timestamp: May 01, 2023, 01:49:01 pm
content: 1-Propanol and ethanol are primary alcohols and are more acidic (as proton donors) than 2-propanol (isopropyl alcohol). The reason is that methyl groups are viewed as electron donors, and the carbon to which the OH group in 2-propanol is attached has two; whereas, in ethanol and 1-propanol, a single methyl or methylene (-CH2-) group is attached to that carbon. Loss of a proton from an alcohol leaves a negative charge on the oxygen. Electron donors make that less stabilized (i.e., less favored) compared to the weaker effect of a single methyl or methylene group. Ethanol is used safely to remove soldering flux.Think of it this way, none of those 3 alcohols is more acidic than water, and PCB's get washed in water all the time.1-propanol will evaporate a little more slowly than 2-propanol, and I don't like its smell as much. There may also be a slight difference in solvent power for flux reside, but probably not anything you will notice.EDIT: It will be fine with solder resist and probably no worse than 2-propanol for any conformal coating. There are different types of conformal coatings.
ISSI Serial Flash Memory Read-Write - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: May 12, 2024, 09:02:59 am
content: Hello,I have the below chip (IS25LP128) and I can’t read it or program it with CH314A programmer. Do you know if there is any compatible programmer or something like this at the below link (I have use it in ATMEL and works fine) with Arduino?AVR Tutorial - Starting out with avrdudehttps://www.ladyada.net/learn/avr/avrdude.htmlIS25LP128https://www.issi.com/WW/pdf/IS25LP128.pdf

author: voltsandjolts
author_rank: Unknown
timestamp: May 12, 2024, 12:26:46 pm
content: IS25LP128 is listed as supported by minipro TL866II PLUShttp://www.autoelectric.cn/en/tl866_main.htmlhttp://www.autoelectric.cn/MiniPro/TL866II_List.txtThese programmers are popular (I have one, I like it), good value and widely available.Beware there are also fake versions of TL866 available.

author: DavidAlfa
author_rank: Super Contributor
timestamp: May 12, 2024, 02:14:07 pm
content: No need of another programmer, NeoProgrammer supports it (It's for CH314A).-Homepage.-Download.

author: 2X
author_rank: Frequent Contributor
timestamp: May 16, 2024, 09:50:39 pm
content: Many thanks for your replies.I used the NeoProgrammer software with CH314A and chip programmed fine.Also, I bought one more advanced programmer just for future needs (link below).100% Original RT809F Programmer+All Adapters SOP8 IC Clip LCD Reader + PEB-1 Expansion board +Edid Cable Free Shippinghttps://vi.aliexpress.com/item/32828024470.html?spm=a2g0o.order_list.order_list_main.127.4c3d1802FfIEhk&gatewayAdapt=glo2vnm
Issue of android 6 SP boot loop  - Page 1
Forum section: electronics / repair

author: abdulbadii
author_rank: Frequent Contributor
timestamp: March 30, 2022, 10:55:14 pm
content: How do we fix android 6 SP ie. smartphone boot loop though it's been factory reset chosen in recovery menu, also battery was pulled and separated, it helped nothing whatsoever ?Sincere help is really invaluable, thanks in advance

author: m3vuv
author_rank: Super Contributor
timestamp: April 01, 2022, 02:57:38 am
content: try wiping the dalvic cache
Issue on GE CG9806 VHS camcorder. - Page 1
Forum section: electronics / repair

author: Beauregard42
author_rank: Newbie
timestamp: January 12, 2024, 11:28:15 pm
content: I recently bought a General Electric CG9806 camcorder off of E-bay, and I tested it, and it works perfectly in every aspect other than the fact the circuit that converts the color carrier in the NTSC signal into the signal that is mixed with the Luma carrier, and recorded onto tape, is dodgy. Result: The signal recorded onto the videotape is B/W, even though the camera is color, and outputs a color signal through the composite output adapter. It can play tapes, with color because the color decoder is working, but the color encoder is not. I think it may just be a bad solder joint or something of the likes, because at one point, I had the camcorder hooked up to my VCR, with the VCR being source, and camcorder being the recorder,(Through adapter) and it recorded the color signal of the blue VCR screen, and then, once the tape in my VCR started, it cut back to B/W, and then two fields later, two fields of video were recorded on the tape in the camcorder with color, and then it cut back to B/W.Anyone know anything about how to service this thing, or what can be done etc?Original E-bay listing:https://www.ebay.com/itm/196074598843?hash=item2da6f4f1bb:g:e3kAAOSw3lFlTlhx&amdata=enc%3AAQAIAAAAwLeALtqaf7ktgkveTDjCgPMzcqXrVErrt1EpLviTvG5%2FHR4G46qMVLOLszdcF%2BOSuTfaI1yPMuq690mcfHgm6cOoD85FrJocZlw09TLbHnQ8K%2FCkXwXjzkpOCjqofa9Y0WR%2FR%2BTKmI%2BGPmqRfuRaPf%2B%2FOQOpKBHkm3f6EzAKncKuVBtIgoRwz%2BDk8dLHldjxP%2F80px0rDxAxJLU4PlYH9R1AB%2BBAFe7iY0UkvJs1E%2F1pD3F1XAtZ7SW27L4kMqMdxg%3D%3D%7Ctkp%3ABk9SR9qGqeyWYw
Issue with my Fluke 79 III  - Page 1
Forum section: electronics / repair

author: bat
author_rank: Regular Contributor
timestamp: February 13, 2024, 07:23:45 am
content: Hi guys,I recently acquired a Fluke 79 III that was going to be discarded, and I've noticed a few issues. The range and yellow hold buttons don't work properly. Sometimes, the hold button works when I press hard enough. I took it apart to have a look, and the contacts seemed to be in good condition. I used a small metal rod to trigger the contacts, and indeed it worked, but it was also failing intermittently. My concern is that the issue might be deeper within the electronics.I have attached a few pictures. I would greatly appreciate any tips from you guys.

author: Greybeard
author_rank: Frequent Contributor
timestamp: February 13, 2024, 09:19:56 am
content: I don't see your pictures.Have you tried to clean the rubber contact and the contacts on the PCB?

author: bat
author_rank: Regular Contributor
timestamp: February 13, 2024, 09:31:58 am
content: I attached a zip files with my pictures, but it seems that it did not work.I have cleaned the rubber contacts but couldn't clean the contacts on the PCB. How did you manage to remove the grey plastic cover ?

author: Greybeard
author_rank: Frequent Contributor
timestamp: February 13, 2024, 06:05:54 pm
content: Quote from: bat on February 13, 2024, 09:31:58 amThat is not my Fluke 79 III, that's what google search found:https://minhcnguyen-blogspot-com.translate.goog/2021/02/ben-trong-dong-ho-do-dien-van-nang-fluke-79.html?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wappHow did you clean the contacts?

author: bat
author_rank: Regular Contributor
timestamp: February 14, 2024, 08:24:43 am
content: Thank you very much mate, I didn't even think of trying to search on youtube for that lolIt's now operational

author: Greybeard
author_rank: Frequent Contributor
timestamp: February 14, 2024, 08:48:27 am
content: What caused the problem?

author: bat
author_rank: Regular Contributor
timestamp: February 19, 2024, 09:27:35 am
content: Contacts (hold & range) were dirty, previous owner used it in a very dirty / dusty environment and never cleaned it.
Issue with tig welder in AC mode - Page 1
Forum section: electronics / repair

author: muzzarobbo
author_rank: Newbie
timestamp: July 23, 2022, 08:05:18 am
content: Hi all,I have a UNIMIG AC/DC 200 W174 tig welder and when welding in AC mode only the electrode negative half of the waveform appears to be functioning (no cleaning cleaning action and struggles to maintain an arc).I pulled the cover off to have a look and could not find any obvious broken wires or burnt out components.I saw a video where someone tested the mosfets with a multimeter so I decided to give that a crack and did actually find one that did not give a value, while the others next to it (in a row) al gave the same value of ~446. The video seemed to imply that a broken mosfet would show as continuity on the multimeter rather than no result however it was in Indian so I could not follow it all.Could this single component be my only issue? is there anything else I could easily check without much risk of zapping myself.TIA!Murray

author: muzzarobbo
author_rank: Newbie
timestamp: July 23, 2022, 08:09:48 am
content: Here are some pics.

author: BrokenYugo
author_rank: Super Contributor
timestamp: July 26, 2022, 11:56:48 pm
content: It's hard to say much without schematics or part numbers.Odd man out is a good clue though, assuming they're all the same part.You may find this video helpful, just note that a power mosfet probably won't be turned on by a multimeter like the little one shown, big power parts usually have a higher threshold voltage than the meter will provide (usually 3V max). In circuit testing can also be problematic.
Issue with Uni-T UT210E clamp meter - Page 1
Forum section: electronics / repair

author: EngPhoeNIX
author_rank: Newbie
timestamp: October 08, 2018, 07:36:14 pm
content: Hi Every one,I get a brand new Uni-t UT210E clamp meter from Aliexpress , once I power up the meter , I get "CAL" on the display , as shown below :https://www.photobox.co.uk/my/photo/full?photo_id=501131967326Then is followed by random numbers also shown on the display , some sort of counting numbers in hexadecimal form :https://www.photobox.co.uk/my/photo/full?photo_id=501131969064Then showing error message " err1" as below :https://www.photobox.co.uk/my/photo/full?photo_id=501131968129& then the device is not responding to any key & hang up , if I pressed the select button several times while the numbers counting I can get the meter ready to measure according to the dial selection , but I doubt it will give the correct measurement , also at that time the hold button do nothing & I can not get the back light operation as well , does any one face this situation with this meter ? does any one can help to fix this issue ?Thank you.

author: JohnPen
author_rank: Regular Contributor
timestamp: October 09, 2018, 09:06:43 am
content: First thoughts are to replace the batteries just in case they are they or their contact resistances are causing problems. Otherwise there is a long thread about the UT-T-210E on EEV that may help as well. Unfortunately it could just be a dud and needs to be returned. Best of luck.https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/John

author: EngPhoeNIX
author_rank: Newbie
timestamp: October 09, 2018, 06:50:02 pm
content: Quote from: JohnPen on October 09, 2018, 09:06:43 amThank you for your reply , I changed the batteries with new ones but still the same issue .

author: alex27riva
author_rank: Newbie
timestamp: June 06, 2021, 08:54:29 am
content: Hi everyone, I have the same problem with my clamp meter, is there any way to fix?

author: Qw3rtzuiop
author_rank: Frequent Contributor
timestamp: June 06, 2021, 09:44:41 am
content: Your meter is in the calibration mode.Its described in this post:https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/350/
Issues with Mackie Micro 1202 Mixer / Flashing Meter Lights?! - Page 1
Forum section: electronics / repair

author: velocity kendall
author_rank: Newbie
timestamp: April 02, 2021, 04:09:50 pm
content: Hi folks,I have a Mackie Micro 1202 mixer which seems to work fine, except that the meter lights for the main output seem to flash on and off when the output volume reaches a certain point.It's fine for the first 3 or 4 bars until it reaches around -7db, then it lights start to flash. They're still reading the output properly; when i turn the output volume all the way up you can clearly see the meter reading fine, it's just that the lights flash on and off roughly twice every second.Any ideas what the issue might be?Thanks in advance.

author: Pete66
author_rank: Regular Contributor
timestamp: April 09, 2021, 09:37:35 pm
content: The LED meter works with LM339 comparators. I would switch them around and see if that makes the LEDs flash at something other than -7db. If it does then one of the LM339's is bad. I would swap U2502 with U2501 fist to see if that changes anything. If it does I would just replace both of them.Also,do you have headphones plugged in? Does it sound fine when using headphones?

author: Audiorepair
author_rank: Frequent Contributor
timestamp: April 10, 2021, 10:09:44 am
content: Does the Rude Solo LED flash at the same rate when operated?The LED section has its own ground return to the power supply, maybe this is bad?

author: velocity kendall
author_rank: Newbie
timestamp: April 16, 2021, 09:11:49 pm
content: Hi pete66,I'll try that, thanks.Yeah, all sounds fine, no problems at all. Just the blinking led meters :0/
IT6322/BK9130-Fuse resistor burned out - Page 1
Forum section: electronics / repair

author: YiWeiXiuEr
author_rank: Newbie
timestamp: September 27, 2025, 03:45:05 pm
content: Hello everyone, this is my first time posting on this forum. If I do anything wrong or offend you, it's not my intention. I apologize in advance. I also hope you can correct my mistakes or tell me the right way to do things. Thank you very much.Here's what happened: A few days ago, I bought an almost brand-new IT6322; according to the factory calibration certificate in the package, it had been dormant in the warehouse for at least 14 years; the seller said it could be turned on, but the VFD screen wouldn't light up; on the forum, I learned that it is actually the same machine as the BK9130; based on the information on the forum, I found that there was a short-circuited and failed capacitor on its CPU board, which caused a fuse resistor to burn out; I replaced the short-circuited capacitor and used a fuse to replace the resistor.Then it worked properly: I pressed the power button, it turned on, the screen lit up, and it could output voltage normally(Figure 1). However, I noticed that a Zener diode on the CPU board was getting extremely hot (Figure 2). I continued to study the wiring on the CPU board and drew the equivalent circuit diagram of this part (Figure 3). It (the Zener diode) seems to be used for powering the VFD screen. Moreover, my action of replacing the resistor (R1 in Figure 4) with a fuse has increased its power consumption, and it may not be operating under normal conditions. But the damaged resistor has been burned black, so I can't determine its resistance value based on its color bands. Its position on the circuit board is shown in the figure (Figure 5).Based on other related posts, I have determined that the burned resistor is likely a 47Ω one. After replacing it, the overheating issue of the Zener diode has been alleviated. However, when operating at a room temperature of 26°C, the Zener diode still maintains a temperature of 65°C, which I believe is still not quite normal.Is there anyone using the same model or BK9130 who can provide a picture of the color bands of a normal resistor? Thank you very much!By the way, the VFD screen of this instrument doesn’t seem very bright. I’m not familiar with this type of device, but the information I’ve gathered indicates that for a VFD screen that has been stored for nearly 15 years (possibly longer), this dimness is a sign of shortened lifespan—and it’s almost irreversible. Is this the case? Or are there any methods to improve this issue? Thank you again for reading and answering!（I have tried my best to upload the images, but the quality turned out to be very poor. Therefore, I have packed and compressed all the images into a zip file. Could you please download and extract the compressed package to view the images? I truly apologize for the inconvenience!）

author: fzabkar
author_rank: Super Contributor
timestamp: September 27, 2025, 06:29:40 pm
content: Under no-load (worst case) conditions the dissipation in the 30V, 1Watt Zener would be ...(48 - 30) / (47 + 750) x 30 = 0.68WThat's OK.
ITE IT8528 EC using RT809H - Page 1
Forum section: electronics / repair

author: IsuissaX
author_rank: Newbie
timestamp: May 25, 2025, 03:14:31 pm
content: Hi all,I am struggeling with an IT8528 EC.I am using the RT809H to read it through SMBUS, in the software terminal i can see that the programmer identify the EC, reads it but always fail when verifing.I have a board with dedicated pins for EC debbuging:GNDEC_SMCLK_DEBUGEC_SMDAT_DEBUGIn addition i have 10 ping for JLPC with the pinout but i have no idea how to connect them to the ID10 ISP of the RT809H.The board model is EBM-BYTANY HELP would be much appreciated.

author: coromonadalix
author_rank: Super Contributor
timestamp: May 25, 2025, 04:17:17 pm
content: DONT double post it annoy peoplehttps://www.eevblog.com/forum/beginners/it8528-isp-rt809h/new/#new
（ITECH）IT8512B  CV could not be loaded - Page 1
Forum section: electronics / repair

author: 晓看风云
author_rank: Contributor
timestamp: April 17, 2025, 02:20:43 pm
content: I need everyone's help, thank you in advance!I have a 500V15A300W electronic load meter, yes, such a high voltage, it is relatively rare, I sold it from the second-hand market.The initial failure is that the CV fails to load, and everything else works fine. In the hands of the previous one, the repair was fruitless, and the fault expanded.At present, when the CC voltage is lower than 36V, it cannot be loaded, or when the current is higher than 5A, the voltage and current will be high and low.In CV mode, it cannot be loaded. All the op amps have been replaced, relays, resistors, ADCs, DACs have been replaced (moved from good instruments, yes, that's what its predecessor did to it. He changed almost everything, but the glitch persisted. ）Since there is no information about this electronic load meter, I had to use my poor knowledge to study it, and after two days of exploration, I found that the TPK test point on the circuit board will output the corresponding voltage with the CC set current or CV set voltage of the microcontroller. Based on this, I confirm that the microcontroller is also normal.One of the things that puzzled me was that when the CV mode was turned on, the TPK was -0.668, and the TL084CN behind it directly output -10V, completely turning off the FET, and I couldn't figure out why, even if I dismantled the TL084CN, it was the same fault phenomenon.When CC mode is turned on, when the maximum current of 15A is set, the TPK will show 6.191V, which I believe should be very normal. However, if the power supply is connected, the power output is set to 40V5A, and if IT8512 is set to 0-4A, it can be started normally, and the voltage and current will jump randomly when it exceeds 4.5A. (The CC voltage must be higher than 36V to start successfully) at this time, if the TPA and TPV are measured, the voltage is both jumping.My meagre knowledge is not enough to keep me exploring, I need everyone's help, please help me as much as possible!PS: I think you've heard that this electronic payload meter has interference problems?

author: 晓看风云
author_rank: Contributor
timestamp: April 19, 2025, 04:09:56 pm
content: Update, CV mode can load, but just like the 5A setting in CC mode, the voltage and current are jumping, like a gorgeous dancer watching me wander helplessly..........
Item 8104SY1 ON XBOX ONE S - Page 1
Forum section: electronics / repair

author: Atom3223
author_rank: Newbie
timestamp: October 18, 2021, 01:41:13 pm
content: Hi.Xbox One S, element on bottom of board U6U1I need to find out, what chip is this. It have on top 8104SY1. I only want to know how this chip is working.5v on VCC i think, comes out 2.5v but i dont know It's appropriate voltage and the chip it's getting hot to 50c. On dead mainboard because i have missing 3.3v.I know IT is familliar topic but i dont find answer do decided to open new one.

author: Manul
author_rank: Super Contributor
timestamp: October 18, 2021, 03:41:13 pm
content: Is this Infineon part? Please post a photo with part number visible (play with light angle).

author: Atom3223
author_rank: Newbie
timestamp: October 18, 2021, 03:51:03 pm
content: I don't know what brand IT is. I can't recognize this symbol.

author: Manul
author_rank: Super Contributor
timestamp: October 18, 2021, 07:57:22 pm
content: That looks like Information Storage Devices logo. ISD8104 audio amplifier?

author: fzabkar
author_rank: Super Contributor
timestamp: October 18, 2021, 08:20:49 pm
content: Here is my BOM (incomplete):https://www.eevblog.com/forum/repair/xbox-one-s-no-power-on-missing-3-3v/iFixit teardown:https://www.ifixit.com/Teardown/Xbox+One+S+Teardown/65572ISD8104 datasheet:https://media.digikey.com/pdf/Data%20Sheets/Nuvoton%20PDFs/ISD8102_04_Preliminary.pdf

author: shakalnokturn
author_rank: Super Contributor
timestamp: October 20, 2021, 10:11:28 pm
content: Am I right in assuming these get blown by connecting equipment to the audio output when powered and without preestablished common ground?
It's a long shot, but I need a manual, Systron Donner 1018 Counter - Page 1
Forum section: electronics / repair

author: L_Euler
author_rank: Regular Contributor
timestamp: June 25, 2019, 02:29:49 pm
content: I've been searching for years, started 30 years ago with no luck. I even called Systron Donner in 1990 and volunteered to search their archives (I lived near their headquarters). To this day I cannot find a trace of this counter's existence anywhere. The 1037 and 1038 seem to be follow up units to this one, and I can get manuals for both of those. However, in spite of nearly identical card setups, the 50MHZ decade card in both the 1037 and 1038 is dramatically different from the analogous 100MHZ card in the 1018. And that is where I'm stuck. If anyone here has a clue about this thing I'd appreciate it.
ITT GX240 Metrix Function Generator - Page 1
Forum section: electronics / repair

author: Orion63
author_rank: Contributor
timestamp: October 28, 2020, 01:54:04 am
content: Hi, I have this ITT GX240 Metrix Function Generator with Frequency counter. It has developed a display problem as shown in the attached picture. All the functions are working alright. Even the digits are displayed correctly, except that the segments G,E and C does not illuminated on the display. I tried taking out the LCD module (40-pin) and cleaning the contacts but was not successful. Could it be a display driver issue or LCD issue? I don't think it is Microprocessor issue as the data is sent correctly to the Display unit. Any help from the forum is appreciated. Thanks for looking.

author: shakalnokturn
author_rank: Super Contributor
timestamp: October 28, 2020, 11:36:02 am
content: To check the driver IC without schematics you'd have to scope all the outputs to the LCD, normal driving levels are (close to) 0V, (close to) Vcc, Vcc/3 and 2Vcc/3.What can also happen with those LCD's is that one of the glass-metal "F" shaped contacts becomes loose.Try applying some pressure to the LCD or contacts individually while it's working see if it makes any difference.
Iwatsu SG-4111 service manual?  - Page 1
Forum section: electronics / repair

author: mpuq
author_rank: Newbie
timestamp: October 31, 2022, 04:48:17 pm
content: Hi,Could anyone point me in the right direction to find a service manual for a Iwatsu SG-4111 function generator. I have a working one, but the frequency isn't stable, it fluctuates just a bit. It fluctuated a bit more with first time starting it, after it had been unused for years. I'm thinking about replacing the power supply caps and the fan of the unit.The service manual would be nice, because in my experience Iwatsu's manuals are great, including problem diagnostic diagrams etc.Thanks in advance for any help!
Iwatsu SS-8120 mainframe and A-880 spectrum analyzer service manuals wanted - Page 1
Forum section: electronics / repair

author: Mike P
author_rank: Newbie
timestamp: March 21, 2021, 10:18:48 pm
content: Hello,I'm struggling to try and repair and old (1980's) Iwatsu spectrum analyzer which I bought recently on the dreaded eBay.The unit I have is ex MOD (ministry of defence) and is a modular type design with a mainframe display unit and a spectrum analyzer plug-in.The mainframe/display unit is an SS-8120 and the S.A. is an A-880.I'm finding it impossible to to get hold of a copy of the service manual. I've emailed dozens of repair shops here in the UK, posted on several forums and I even tried emailing Iwatsu and Japanese!Iwatsu kit is very rare in the UK and I'm hoping (praying) that someone in Australia or the U.S. might have a copy, or be able to help me with the repair.One more thing; the mainframe of my SS-8120 looks visually very similar to that of the TS-8123, so a service manual for the TS-8123 might be helpful.Many thanks, Mike

author: Mike P
author_rank: Newbie
timestamp: March 25, 2021, 10:06:32 pm
content: Still looking.Anyone got one?

author: coppercone2
author_rank: Super Contributor
timestamp: March 26, 2021, 06:43:18 am
content: No, but if you have all the parts you might be able to figure out what the problem is.maybe we can give you a clue and it would make the thread more entertaining if you described the problem.There is some good things to test like if the reference oscillator is working, if there is activity on certain digital circuits, etc. But my luck with SA repair is terrible, usually the main problem is even if you have a manual, the extension cards are a problem.Start with the voltage rails, hopefully its a bad voltage rail so you can find the problem. If its a signal problem you need to go in deep.See if you can even make or get extension cables, because with out them, with modules, your gonna have a really really tough time. Insanely hard IMO. You can guess at a few things by attaching thin probes and reinserting but its like some 'fix my space ship to get back to my home planet' type of shit, twilight zone episode.Every mainframe ever manual for service is going to have some kind of difficult to obtain cable or card extender, which you will likely need to figure out if you can make.
Iwatsu SS7821 scope - Page 1
Forum section: electronics / repair

author: Willy Potato
author_rank: Newbie
timestamp: March 07, 2023, 12:27:34 am
content: My Iwatsu SS7821 oscilloscope displays “Panel Locked” with any push of a button or knob twist on the control panel.No modes change. The manual does not address this issue.The sweep and the vertical amps are OK and stuck in the last working panel setup.Lost. Where to start?

author: coromonadalix
author_rank: Super Contributor
timestamp: March 07, 2023, 05:29:44 pm
content: http://bee.mif.pg.gda.pl/ciasteczkowypotwor/Iwatsu/https://www.eevblog.com/forum/repair/help-me-repair-iwatsu-ss-7821-200mhz-osc/https://www.download-service-manuals.com/en/model.php?id=16416?power supply problems ?

author: ciasteczkowypotwor
author_rank: Contributor
timestamp: October 16, 2023, 12:05:37 pm
content: Press Holdoff and Coupling.

author: Willy Potato
author_rank: Newbie
timestamp: December 06, 2023, 02:33:20 pm
content: I just saw your post today 12/06/23. Pushed the buttons with power off, turned it on and what do you know?CUBS WIN! It works. Thank you so much. I can put the Leader back on the shelf.Willy
Jaguar Radio AJ9100/9200 Schematic - Page 1
Forum section: electronics / repair

author: Retired2
author_rank: Contributor
timestamp: April 22, 2025, 06:23:42 pm
content: HI,I am in need of a 1991 Jaguar Radio AJ9100/9200 schematic. Its made by Alpine and the closest i can find is a Alpine 7390M. I have located the data sheets for the chips and the cassette deck mechanism. The design of the radio is significantly different.Any help will be greatly appreciated.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: April 22, 2025, 11:16:16 pm
content: Very few OEM Alpine schematics were ever released, none of what you want.If you want one you have to make it as well as the harness connectors for Most Jaguar radios.What are your problems?Jeff

author: Retired2
author_rank: Contributor
timestamp: April 24, 2025, 12:46:32 pm
content: I have two in-dash radios.Both were working with the same issue the cassette deck nonfunctional.Original deck had bad belt but won’t operate. Replacement deck had overheated now open eject solenoid.After sitting on the bench both units will not turn on no display. Both have no 4.19Mhz clock at the main CPU. I replaced the dead backup CR2032 battery to no avail.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: April 25, 2025, 01:17:17 am
content: Both models have capacitor problems, and leaky caps cause bad runs, even the back-up battery can leak.Check main PCB very closely for corroded runs, and feed-through's, open runs can be hard to spot when the open is microscopic.Cassette tape problems are various electronic and mechanical, most times clean and lube and belt. Solenoid, motor, IC and gear are next.Sometimes bent mechanism.Jeff

author: Retired2
author_rank: Contributor
timestamp: April 25, 2025, 01:23:40 pm
content: Thanks you for the tip!Both units had bad runs found by my Opti visor. Now to get the microscope camera inspection for the other detailed work.In the interim, I am going to install another radio and CD deck in the trunk.

author: Retired2
author_rank: Contributor
timestamp: April 25, 2025, 06:31:40 pm
content: Observing under the Camera Microscope reveals a lot of cold solder joints. There are too many to isolate so I am going to resolder the board definitely plated side and some on the component side.A few traces from the 17 pin Cassette connector are overheated so I will be repairing them.Looks like trace width was under estimated for current flow.There is no designation for Lead Free so I assume its a mixture of lead and tin. Around 1990 Lead free was just starting in PCB's.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: April 25, 2025, 09:48:39 pm
content: Your welcome, bad solder connections are normal in many OEM units.Use a good quality normal solder.Jeff

author: Retired2
author_rank: Contributor
timestamp: April 28, 2025, 03:56:31 pm
content: This is an example of Leaky Caps in a similar Radio. NOT my radio but I have similar leakage problems.
Jaycar Powertech MP3842 stays in CC mode, anyone has a schematic? - Page 1
Forum section: electronics / repair

author: Pauldg123
author_rank: Contributor
timestamp: March 12, 2021, 10:47:29 pm
content: Just brushed off my Powertech MP3842 Power Supply (in storage for 1 year). Now the power supply goes into CC mode after switching it on.Is there a short in the power supply that it jumps from CV to CC mode? The unit has very unusual triangle slotted screws so I have not opened it yet but will see if I can find a proper type screw driver.Anyone who has a schematic of this power supply? Uncle Google has not turned up anything.Thanks, Paul

author: sidds
author_rank: Newbie
timestamp: July 31, 2022, 11:17:18 am
content: It is most likely faulty GR8762 8pin soc as per attached pic.
Jbc ad 2200 sleep temp setting - Page 1
Forum section: electronics / repair

author: I AM A TENT
author_rank: Newbie
timestamp: May 27, 2022, 08:38:24 am
content: Hey! First post on the forum so I will also introduce myself. I am an student currently finishing a master in embedded systems so it is said i got a good knowledge about electronics.I recently scored a bargain on a functioning JBC AD 2200 soldering iron. Soon after recieving the unit I wanted to start checking temps after thourghly cleaning the unit. The temps were a bit off (like 10 to 15 degrees) but this is probably due to my thermal camera. The sleeping temperature, so when the tool is inserted into the holder, is around 250/260 ish degree Celsius which is a bit high for my liking. I was looking into in how to change this and found out that a JBC AC 2600 is needed but that unit (if found anywhere) is freaking expensive. I found another old post here (linked below) where the EPROM was taken out and reprogrammed. I got acces to tools to desolder the eprom but I have no idea which parameters to change un the memory and don't want to mess it up.If anyone knows how to identify where every byte stands for or has experience with this kind of modification please let me know.The old post:https://www.eevblog.com/forum/reviews/jbc-ad2700-soldering-station-fixed-temperature/
JBC AM station repair help - 2UA - Page 1
Forum section: electronics / repair

author: bufalo88
author_rank: Newbie
timestamp: January 30, 2024, 09:55:38 am
content: Dear friends and colleagues of the forum, I ask you for help in trying to repair this station, it presents the following error on the display"attention sensor temperature error; and the desoldering iron turns on fire. The hot air works. I thank those who want to participate.If anyone has the wiring diagram it would be appreciated, I'll add some photosPs. I apologize for the English but I use google translator

author: bufalo88
author_rank: Newbie
timestamp: January 30, 2024, 10:05:56 am
content: From the card you can see that several components are missing that concern the channel dedicated to the DR5650, I tested the four mosfets and they were good

author: Hydrawerk
author_rank: Super Contributor
timestamp: January 30, 2024, 07:27:57 pm
content: Quote from: bufalo88 on January 30, 2024, 09:55:38 amDo you have another handle like a T245?https://www.jbctools.com/t245-handles.htmlDid you try it?There are probably two channels on the JBC AM. Do both channels do the same error?

author: Hydrawerk
author_rank: Super Contributor
timestamp: January 30, 2024, 07:31:29 pm
content: I am not sure if an user manual helps you but here it is anyway.

author: bufalo88
author_rank: Newbie
timestamp: January 31, 2024, 11:52:38 am
content: Hydrawerk thanks for the answer yes the station has two channels one for c245 and the other for the dr 5650 unfortunately the station is stuck on temp sensor error and doesn't even work with the c245 stylus.Can you help me? I have disassembled many components to test them but I can't find the faulty ones

author: uli12us
author_rank: Contributor
timestamp: January 31, 2024, 12:08:34 pm
content: Have you tested the connections, Plugs from the iron to the PCB as well?

author: bufalo88
author_rank: Newbie
timestamp: January 31, 2024, 02:28:24 pm
content: Yes, I have tested them, the fault is definitely on the main, you have the opportunity to give me further ideas.I would like to read the microprocessor to see how it handles errors.any form of help is certainly welcome

author: minimania
author_rank: Newbie
timestamp: January 30, 2025, 11:35:26 pm
content: hidid you manage to get any info on this please?i have a similar unit that just stopped working and would like some info onthanks

author: Domelec
author_rank: Newbie
timestamp: October 11, 2025, 04:55:46 pm
content: Why is there never any replies to this ?Does anyone have any info on repairing these units please
JBC DM-2B EEPROM issue fix - Page 1
Forum section: electronics / repair

author: nikifena
author_rank: Regular Contributor
timestamp: April 01, 2024, 12:02:31 pm
content: Hi there. I just wanted to share my experience with a JBC DM-2B soldering station I had.I ordered this 4-tool station secondhand. Everything worked fine, but I found that when I changed the iron temperature and turned the station off, and then on, it starts at 400C degree. This is not a normal condition of all JBC stations I have/had, so I thought there is an issue.I sent a mail to JBC, but based on my experience, no support from them. They told me it was an obsolete station, and they didn't have spare parts. No answer when I asked for the EEPROM BIN file. I've asked a few times for technical support from them without luck! I needed to cope by myself.As usual, I opened it. The processor is a PIC micro, and there is an EEPROM. In this case, it's 24C16. I removed it, read it, saved the BIN file, and tried to change some bits on the original EEPROM. Unfortunately, the programmer returned errors. Then I got a new one, programmed it with the downloaded BIN file, and soldered on the PCB. With the new chip, everything works perfectly now!Just wanted to share my experience here, providing the BIN file + a photo with the EEPROM.Hopefully, this topic could help someone else with the same issue in the future.
JBC resistor ID for md-2960 - Page 1
Forum section: electronics / repair

author: Syzeryuino
author_rank: Contributor
timestamp: December 12, 2024, 12:46:50 am
content: Hey guys, recently I acquired the MD-2960 soldering station without the handle. It's supposed to come with the DR-3600 micro desoldering gun, i couldn't source that part but was able to source the dr-5600. but it kept saying "WRONG TOOL", I'm pretty sure this is due to the resistor ID in the connector, both are rated to 75w, so I'm pretty sure both are 24v models not the 48v high power model (150w-200w) iron. does anyone know the value resistor I should replace it? I looked around and couldn't find any informationthis is the manual for the station:https://www.jbctools.com/pdf/manual_MD2960.pdfand for the iron that i have is the DR-5600https://www.jbctools.com/pdf/manual_DR5600.pdf

author: thm_w
author_rank: Super Contributor
timestamp: December 12, 2024, 01:20:43 am
content: Since it has a screen, can you just try a 500k pot and check various values?They usually use stuff around 10-100k afaik, or shorted/open.

author: Syzeryuino
author_rank: Contributor
timestamp: December 12, 2024, 01:28:45 am
content: good point, will try to do that after I acquire the pot. just moved to another country so, I don't have a lab anymore (probably wont set it up).
JBC SL-2300 - Page 1
Forum section: electronics / repair

author: lionelkjh
author_rank: Frequent Contributor
timestamp: April 24, 2024, 04:46:31 pm
content: Good evening; I am currently repairing a JBC SL-2300 soldering station which fully regulates the temperature...After disassembly; I notice that the electronic card has 2 wires at a corner of the card where the sector arrives; which justifies the inoperative regulation... My question is therefore: what is this component replaced by a piece of wire? Resistors; diodes?? What are their respective values? In addition I would also like to replace the complete iron because some parts are missing....Here are the card references: JBC 0223395...If anyone can help me find these 2 missing components as well as the iron; that would be great! I am attaching the photos I took.....Thank you for your valuable help!

author: lionelkjh
author_rank: Frequent Contributor
timestamp: April 25, 2024, 11:24:04 am
content: Good morning; I also specify that the voltage measured on the iron is of the order of 160v which causes the resistance to glow quite quickly; I unplug it immediately! The voltage should be close to 24v; we therefore have a tension 5 times greater....Cdt

author: fzabkar
author_rank: Super Contributor
timestamp: April 25, 2024, 10:54:40 pm
content: According to the exploded diagram on page 12 of the user manual, it would appear that this station has no stepdown transformer. Therefore, the heating element must be controlled via a TRIAC. I would think that you would need to measure the heater voltage with an RMS voltmeter.Page 13 identifies the part numbers of the individual components of the handpiece.https://www.jbctools.com/pdf/manual_SL2300.pdf

author: lionelkjh
author_rank: Frequent Contributor
timestamp: April 28, 2024, 07:06:05 am
content: Hello, and thank you for the feedback...I have the documentation for this product, but unfortunately I am looking for the diagram, or photos of the board of a functional soldering station....I measured the tension on the iron; it is located at 160v and should be around 24v...Cdt

author: lionelkjh
author_rank: Frequent Contributor
timestamp: May 04, 2024, 07:33:32 am
content: Good morning; if anyone has this model; could you give me detailed photos of the card??? Thanks in advance

author: m k
author_rank: Super Contributor
timestamp: May 04, 2024, 11:22:54 am
content: Sorry, no photos.But something from your photos.Brown in is possibly a fuse, it goes to diode.Blue in can also be a fuse, it goes under the button and space is too small for black diode used elsewhere.But blue in wire shouldn't touch the 100k resistor, it might be so in first picture.Other side of the button is a black diode.If it's positive end is directly connected to blue in there is a full wave rectifier of some sort.Half wave rectifier there clearly is since brown side diode is the only thing through what electricity goes.The side also seems to be straight through, return is unknown.