hybridfree/eevblog-posts huggingface dataset:
trying to source replacement fuse - Page 1
Forum section: electronics / repair

author: sanman
author_rank: Contributor
timestamp: July 28, 2016, 01:38:02 pm
content: Hi!I have a 5x20mm 5A 500V fuse that I need to replace.Is the 500V listed on the fuse referencing AC or DC voltage?In looking through the Littlefuse catalog the highest I could find in this form factor is 500VAC. The DC is usually listed around 400V.

author: grifftech
author_rank: Frequent Contributor
timestamp: July 28, 2016, 03:18:20 pm
content: What is the fuse for?

author: sanman
author_rank: Contributor
timestamp: July 28, 2016, 03:31:25 pm
content: The fuse goes in anelectronic ballastfor a stage light. My understanding is that it is a DC voltage moving through the ballast to the igniter.Basically, I'm trying to figure out the DC voltage rating for this fuse.

author: SeanB
author_rank: Super Contributor
timestamp: July 28, 2016, 05:49:44 pm
content: As this fuse most likely is in the AC input to the electronic ballast use a 500VAC fuse. The current in this fuse will be AC from the power line, though the electronic ballast might have a high voltage DC bus inside, the lamp itself will be run on high frequency AC to keep the electrodes wearing unevenly. This will not apply to a Xenon arc lamp, which does use DC as the one electrode is much larger to handle the heating, but even there the fuse will be in the incoming AC side in any case.

author: sanman
author_rank: Contributor
timestamp: August 01, 2016, 01:20:27 am
content: Thank you for the help
Looking for a micro usb smd pcb tower connector for repair of TomTom Start 60 - Page 1
Forum section: electronics / repair

author: obiwanjacobi
author_rank: Super Contributor
timestamp: July 29, 2016, 12:41:21 pm
content: My TomTom Start 60 has intermittent USB connection resulting in random phantom screen touches and trouble with charging. Driving on bumpy roads causes the unit to become unusable.The USB connector seated in the connector is very wobbly and I think that is the problem. I have opened my TomTom up and soldered the case/ground leads but that did not do the trick - I think the connector is broken internally.A somewhat unusual USB connector is used in the TomTom Start 60. I think they call it a tower USB connector for it's receptacle is lift of from the PCB some distance.I think its very similar to this one:http://www.ebay.co.uk/itm/tomtom-Parts-NEW-Micro-USB-TOWER-socket-Weison-G3515-39-x-1-Piece-/232022627785I was just hoping I could get one for less than 10 pounds per piece...Any ideas?Thanx.

author: stj
author_rank: Super Contributor
timestamp: July 30, 2016, 01:22:28 am
content: did you try another cable first?

author: obiwanjacobi
author_rank: Super Contributor
timestamp: July 30, 2016, 06:14:18 am
content: Quote from: stj on July 30, 2016, 01:22:28 amNo, because it has a specific connector and just wiggling the cable in the TomTom socket also reproduces the problem...

author: stj
author_rank: Super Contributor
timestamp: July 30, 2016, 01:31:50 pm
content: maybe the bad contact is on the cable end.what's so "custom" about it?

author: obiwanjacobi
author_rank: Super Contributor
timestamp: July 30, 2016, 01:50:36 pm
content: (in the meantime) I did try another cable and it does fit -did not expect that- but the problem is still there. Although the original cable might also have problems so I will be replacing that, but a new cable is does not fix it.Thanx.

author: jkf1000
author_rank: Regular Contributor
timestamp: July 30, 2016, 09:56:57 pm
content: The Ebay link you supplied quotes £5.99 and £3.49 shipping to the Netherlands. By my maths that still works out at under the £10 you mentioned.. Karl
Tektronix 2247a calibration frequency off - Page 1
Forum section: electronics / repair

author: schulteaaron5
author_rank: Contributor
timestamp: July 29, 2016, 06:49:30 pm
content: Hi, I just bought my first oscilloscope! I couldn't say no to 50 bucks for the 2247a in supposed working order, but I do have the option to return it. I haven't even had a chance to power it on yet but I know the "probe adjust" calibration frequency is off by almost 100hz! Out of 1khz! Maybe I'm using the wrong terminology, but I couldn't find any general info on this issue. I know tek scopes can be hard to fix, but I would love to get this thing up and running!First post, go easy!

author: tggzzz
author_rank: Super Contributor
timestamp: July 29, 2016, 09:03:35 pm
content: Quote from: schulteaaron5 on July 29, 2016, 06:49:30 pmThat output's frequency and amplitude are unimportant; what matters is a flat top and short edges. The only time you use that output is when you are fiddling with a "high" impedance *10 probe's frequency compensation, where you fiddle until the waveform's top looks flat, like a good square wave.BTW, please add a country flag, via the "profile"; that way you might get more relevant information.

author: schulteaaron5
author_rank: Contributor
timestamp: July 29, 2016, 10:06:31 pm
content: Thanks a bunch, I just booted it up and squared off the calibration signal, looks nice at flat now as you'll see in my pictures...pictures i post because now I have an interface issue, I hope its all my fault and not the scopes!I can't get the menu to pop up, pretty sure I've tried every "reasonable" button. Also I don't get a legible "readout" on what my time division and v/div are. Turning up readout brightness just makes some scribbles appear, stuck in the center of the screen as seen in pics. Let me know if I should delete this and start a new postSent from my A0001 using Tapatalk

author: singapol
author_rank: Frequent Contributor
timestamp: July 30, 2016, 04:27:15 am
content: Try displaying two or 4 trace and see where text line is positioned.I suspect vertical knob is moved. The text line should appear at the last bottom grid position. The size of the alphabets is small/abnormal, could be some problem in the readout section. Unable to find operator's manual only service manual so a video will have to suffice. 2447a has about 30 engineering changes from 1989 to 1993 ( see service manual).2247a scope familiarisation video:2247a service manual (129.4 Mb file! 370 pg.): Wait for "Processing" to change to "Get manual".http://elektrotanya.com/tektronix_2247a.pdf/download.html
Power supply for Corsair SP2500 - Page 1
Forum section: electronics / repair

author: DONK
author_rank: Newbie
timestamp: July 23, 2016, 12:38:31 pm
content: Hi allI'm looking for a bit of help to fix my speakers that went pop 3 days ago, they are out of warranty and replacement parts are not available to buy from the company. I have found 2 damaged components on the board which are a resistor and what I think is a mosfet from googling the markings on the top of it but I'm not sure as there seem to be different variants of it so I would like some advice to make sure I am going to replace the correct part.Sorry if I come off as a noob this is the first time I have attempted repair work on something.The full markings on it areAUK42bO1SMK1060Here are some pics of the damage.Blown fuse.Thanks to anyone who takes the time to look at this post.

author: wraper
author_rank: Unknown
timestamp: July 23, 2016, 01:53:13 pm
content: PWM controller IC most likely is dead too. New mosfet quiet likely will blow up too if old IC left. Mosfet quiet obviously is SMK1060F.

author: DONK
author_rank: Newbie
timestamp: July 23, 2016, 05:10:44 pm
content: I have identified the PWM controller it's a 3843GM-E1 is there any way to test these to see if they are dead or not?

author: wraper
author_rank: Unknown
timestamp: July 24, 2016, 09:12:31 am
content: It's UC3843 or it's clone. There is no way to reliably test it without applying power to it. You can try measure it's mosfet driving output resistance to the GND, if resistance is low, it's 100% dead. From experience, it has 90+% chance to be faulty anyway. When mosfet fails, usually it applies high voltage to IC output through it's gate pin.

author: DONK
author_rank: Newbie
timestamp: July 29, 2016, 07:16:05 pm
content: I have fixed the power supply and the speakers power up again but some part of the amp is also dead as the volume is very low. Think I'm gonna let someone who knows about audio equipment take a look at it now as there could be more wrong with them than I thought in the beginning.Thanks for the help in getting me this far.
Korad KA3010P error: voltage collaps - Page 1
Forum section: electronics / repair

author: JayPeeAge
author_rank: Newbie
timestamp: August 01, 2016, 11:20:38 am
content: My Korad psu has a error now: it could'nt hold the voltage?The video shows the problem.https://youtu.be/TmpefJvQGdYI bought the psu in 03/2015. The dealer says 12month warranty and so the warranty is over. But the manufactor writes 24 month?The Korad has also a untouched warranty seal from the dealer.“There is 2-year warranty for our products and the prompt response will reach you from our service team.”http://koradtechnology.com/en/About%20Us.htmlWhat should i do?

author: madires
author_rank: Super Contributor
timestamp: August 01, 2016, 11:35:27 am
content: Ask Korad how they would handle this, expecially the shipping. If you would have to pay for shipping to China, it's better to try to repair the PSU or buy a new one.

author: JayPeeAge
author_rank: Newbie
timestamp: August 02, 2016, 10:04:59 pm
content: I opened the Korad and searched for errors. But i didn't found anything! I assembled it and now its working fine now O0I also changed the noisy fan.

author: bitseeker
author_rank: Super Contributor
timestamp: August 02, 2016, 11:22:55 pm
content: Sounds like there might be a bad connection inside. Check for cold/cracked solder joints on wires and components.
What is this device?? - Page 1
Forum section: electronics / repair

author: iXod
author_rank: Frequent Contributor
timestamp: July 29, 2016, 06:39:11 pm
content: Marked "D1023". TO-220 package.Can't find datasheet for 2SD1023. Tests as dual-junction device as if BJT.Ideas?Thanks.

author: bktemp
author_rank: Super Contributor
timestamp: July 29, 2016, 06:43:09 pm
content: Quote from: iXod on July 29, 2016, 06:39:11 pmhttp://bfy.tw/6ydE

author: iXod
author_rank: Frequent Contributor
timestamp: July 29, 2016, 06:44:51 pm
content: Yeah, just saw that just before you posted. Thanks!(Is there a way to delete messages after posting?)

author: Kilrah
author_rank: Unknown
timestamp: July 29, 2016, 06:50:14 pm
content: There is a "Remove" button at the top/right of the post.
Needing help identifying a couple of components - Page 1
Forum section: electronics / repair

author: jamiec
author_rank: Contributor
timestamp: July 27, 2016, 09:18:14 pm
content: Hey, Thanks for looking at my post. I am looking to identify 2 components on a PCB i am repairing.The board is used for heart rate so i am assuming one is a sender and one is a receiver for the heart rate.Thanks in advance for any help.Jamie

author: Gyro
author_rank: Super Contributor
timestamp: July 27, 2016, 09:30:31 pm
content: If it's from a pulse oximeter (heart rate plus O2 saturation) then the top picture is a dual LED, one Red and one IR die. The bottom one is a photodiode.

author: jamiec
author_rank: Contributor
timestamp: July 27, 2016, 09:33:27 pm
content: Thats fantastic, Thank you very much.I have just checked the top chip with my Diode Tester and it does emit red light.Thank you very much for your help.Jamie

author: Gyro
author_rank: Super Contributor
timestamp: July 27, 2016, 09:38:20 pm
content: You're welcome.Chris

author: StillTrying
author_rank: Super Contributor
timestamp: July 27, 2016, 10:03:38 pm
content: You should be able to see the IR bit by viewing it through a phone camera!

author: noidea
author_rank: Unknown
timestamp: July 28, 2016, 03:42:48 pm
content: Quote from: StillTrying on July 27, 2016, 10:03:38 pmJust don't to use an iphone rear camera as they have an IR blocking filter in them
Strange flex cable traces material? - Page 1
Forum section: electronics / repair

author: frenky
author_rank: Unknown
timestamp: August 01, 2016, 05:35:33 pm
content: I'm trying to fix a pump controller for a friends friend.There was a shorted voltage regulator that I have already fixed and the only thing left to repair is teared flex cable.Traces are sandwiched between two layers of plastic foil. So I peeled top layer off.Traces are made from some kind of silver sparkly stuff...I tried soldering it but the traces just turned grey and solder did not stick to it.Anybody has an idea how to solder to it or fix it in some other way?Tnx.

author: Twoflower
author_rank: Frequent Contributor
timestamp: August 01, 2016, 05:52:07 pm
content: You might try some electrical conductive glue/colour (something like LOCTITE® 3863) to repair the flexcable. Probably even teh manufacturer used such material to print the wires on the foil.

author: frenky
author_rank: Unknown
timestamp: August 01, 2016, 07:01:55 pm
content: Thank you for a good advice.

author: Kilrah
author_rank: Unknown
timestamp: August 01, 2016, 07:12:01 pm
content: Ugh, these things are awful. Super fragile and a PITA to repair.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: August 01, 2016, 07:28:08 pm
content: It's printed silver ink. May be fixable using silver paint or epoxy. You won't solder to it.

author: Twoflower
author_rank: Frequent Contributor
timestamp: August 01, 2016, 07:31:11 pm
content: Actually the more time I'm thinking of it, the more sceptical I get with my own suggestion.As the tape moves the connection will break immediately. At least you need to do something in addition to either prevent movement in the defective area. Or adding some thin copper wires bridging the crack and glue them with the stuff and probably stiffen the area as well.

author: RobK_NL
author_rank: Frequent Contributor
timestamp: August 01, 2016, 07:37:13 pm
content: There are special pens available with which you can redraw the broken lines.http://nl.farnell.com/chemtronics/cw2900/flex-conductive-pen/dp/1663188Ridiculously expensive stuff, but it works.

author: frenky
author_rank: Unknown
timestamp: August 01, 2016, 07:51:30 pm
content: Thank you guys!I have just ordered a few of these:https://m.aliexpress.com/search.htm?keywords=silver%20conductive%20glue&sortType=TC_D&shippingCountry=SI&viewtype=1I will put bare copper wire over the crack on each line and glue it with this silver glue.That should conduct ok.Then I'll put a blob of epoxy on the top and bottom for better strength.The cable is only moved when opening the case so hopefuly it will last.Tnx again.
What's the value written on this capacitor? - Page 1
Forum section: electronics / repair

author: azigta
author_rank: Regular Contributor
timestamp: July 26, 2016, 07:10:29 pm
content: Hi, I'm trying to repair a pc motherboard and I have to replace 3 electrolytic capacitors labeled "FP 13Bx 101 16" but I don't know how to read that :\ Maybe someone here can help meThanks

author: Jwalling
author_rank: Unknown
timestamp: July 26, 2016, 07:18:36 pm
content: Are they aluminum types? If so, I would say 10uF 16VDC. A picture would be helpful.Jay

author: PA0PBZ
author_rank: Super Contributor
timestamp: July 26, 2016, 07:21:30 pm
content: I think 101 is more like 100uF

author: azigta
author_rank: Regular Contributor
timestamp: July 26, 2016, 07:25:26 pm
content: Quote from: Jwalling on July 26, 2016, 07:18:36 pmHi, thanks for the reply. Here you have apicture. As you can see it's aluminum. I also believe that is 10uf 16VDC. Can you confirm that by seeing the picture? ThanksMaybe it's helpful to say that those 3 capacitors were located close to the I/O port usb ports. The motherboard is an Asus P8P67 rev 3.1 if that helps

author: Cubdriver
author_rank: Unknown
timestamp: July 27, 2016, 05:37:28 am
content: Looks like 100uF, 16V.Mightbe Panasonic FP series, but the markings don't match what's shown in the data sheet Mouser currently links to. It may be an older cap and they've changed the markings, or it may be a different manufacturer/series. It does look like 100uF @16V, though, whoever made it...The marking is typically digit-digit-multiplier. Think of the multiplier simply as the number of zeroes to put after the digits. In your case, 1-0-with one additional zero for 100uF. 471 would be 470uF (4-7-with one additional zero), 1000 would be 102 (1-0 and two more zeroes) and 100 would be 10 (1-0-with zero additional zeroes resulting in 10uF)It gets a little weirder when they're values with a decimal; those are typically displayed with an 'R' where the decimal point would be, thus still giving a three digit code. For instance, 2.2 uF would be shown as 2R2, and 0.47uF as R47.Hope this helps.-Pat

author: azigta
author_rank: Regular Contributor
timestamp: July 27, 2016, 12:55:20 pm
content: Quote from: Cubdriver on July 27, 2016, 05:37:28 amThanks, I'll replace it with 100uF 16V capacitors.
Thermal "socks" for MOSFETs? - Page 1
Forum section: electronics / repair

author: iXod
author_rank: Frequent Contributor
timestamp: July 26, 2016, 04:26:58 am
content: Never seen this arrangement of heatsink thermal pads:http://imgur.com/a/ioVUrWhat are the little "socks" that slip over the MOSFETs? And the aluminum shield between the sock and the large thermal pad?Maybe modern replacement MOSFETs will have lower on-resistance and run cooler so I don't have to chase down new socks (these deteriorated during disassembly).This is the control voltage supply SMPS in a '95-vintage bindery machine (sorts & staples).Thanks.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 26, 2016, 05:55:42 am
content: That's for creepage -- putting a lot of distance (and insulation) between high voltage (mains) and the heatsink (ground).The shield tab is for, well, shielding. I recommend leaving it in. At worst, the unshielded EMI causes internal interference, skewing output voltages and frying the equipment (or interfering with other systems inside, causing malfunction). At best, EMI emissions are increased slightly, and you (or your customer?) comes back later, with a C&D notice from the FCC (or other gov't organization).So, you can use an over-sized insulator, of whatever material, or the "sock" and tubular kinds are still around.Tim

author: b_force
author_rank: Super Contributor
timestamp: July 26, 2016, 05:02:30 pm
content: Seen these 'socks' a lot. I found them very horrible, they break pretty easily if you try to repair stuff.Definitely not something I would rely on for safety creepage

author: Kilrah
author_rank: Unknown
timestamp: July 26, 2016, 05:31:30 pm
content: Just took apart my first device that had that a week ago. Have also torn the first one I removed when it was a lot less resistant than I'd have thought, then was careful removing the others and got them out in one piece.

author: iXod
author_rank: Frequent Contributor
timestamp: July 27, 2016, 02:37:42 am
content: Quote from: Kilrah on July 26, 2016, 05:31:30 pmAre you repairing this? Where did you source replacement socks?Thanks.

author: batteksystem
author_rank: Regular Contributor
timestamp: July 27, 2016, 04:27:52 am
content: Quote from: blueskull on July 26, 2016, 05:00:09 amThe ideal characteristics will be:1. High dielectric strength2. Non-flammable3. Mechanically strong4. Not brittle5. Cheap

author: Kilrah
author_rank: Unknown
timestamp: July 27, 2016, 06:17:37 am
content: Quote from: iXod on July 27, 2016, 02:37:42 amI only ripped a bit of it since I stopped pulling as soon as I saw it tear and it's on the front side so it'll still be good enough to reuse, I'll just fit it on a secondary side part instead of the primary one it was on for good measure.
Tektronix 2230 Issues - Page 1
Forum section: electronics / repair

author: hadmeister
author_rank: Newbie
timestamp: July 25, 2016, 05:19:09 pm
content: Hello, I ve bought an old Tektronix 2230 and it has some issues. The biggest one is that I can not focus the traces (or the readout text), the intensity knobs don´t work at all and so the scope is stuck on full brightness. In addition the blanking is not working quite right. I checked the PS for ripple or voltage issues and it turned out to be just fine (besides the 2kV rail, I don´t have a meter to do it) I think there must be problem somewhere in the Z axis driver, but in the service manual the waveforms are almost unreadeable. The only thing I can tell for sure is that the waveform going out from the Z axis amplifier looks the same as the waveform in the manual, as far as I can tell from the poor quiality picture. There is unfortunately no waveform or voltage that I could check after the DC restorer. The other problem is that it shows up a powerup failure on startup, unfortunatelly, due to the blurry image, I can not read it to get more info. on that, could be just the battery because other than that the scope appears to be working jsut fine. Can you help me please?

author: singapol
author_rank: Frequent Contributor
timestamp: July 26, 2016, 04:31:07 pm
content: Reading this will help:www.sphere.bc.ca/test/tek-parts/troubleshooting-scopes.pdfCheck the intensity and focus circuit but be careful of high voltages!Edit: Read the adjustments of power supply and crt on pg. 5-4 t0 5-5.

author: hadmeister
author_rank: Newbie
timestamp: July 26, 2016, 06:29:00 pm
content: After some poking around. It unfortunately looks like a bad CRTThe bias of the control grid changes between app. 40 to 70 V as I turn the intensity pots but the intensity itself does not change at all.I will try to look more closely at the caps and diodes in the DC restorer but my hope for feasible repair is slowly disappearing. If the fault won´t be there I will have to live somehow with that.
Glue Removal From a Connector - Page 1
Forum section: electronics / repair

author: ENG.Tech
author_rank: Newbie
timestamp: July 08, 2016, 04:53:12 pm
content: Guys I am trying to remove a connector which is glued to a PCB the connector is coming form a small LCD display unit. What is the best way to remove the glue before de-soldering the connector from the board.Thank you very much

author: TheAmmoniacal
author_rank: Unknown
timestamp: July 08, 2016, 04:59:57 pm
content: Cyanocrylate, epoxy or silicone?

author: ENG.Tech
author_rank: Newbie
timestamp: July 08, 2016, 05:51:25 pm
content: its silicone

author: ENG.Tech
author_rank: Newbie
timestamp: July 08, 2016, 05:55:38 pm
content: please see the connector's photo belowhttps://drive.google.com/open?id=0B8nQliUZiP_0OVNmWXU3UlJPekE

author: TheAmmoniacal
author_rank: Unknown
timestamp: July 08, 2016, 06:00:44 pm
content: Looks like ABS to me, try soaking it in acetone.If it's silicone, go buy some hexamethyldisiloxane

author: ruffy91
author_rank: Regular Contributor
timestamp: July 08, 2016, 07:15:44 pm
content: Looks suspicoiusly like hot melt glue to me. Try to just solder through it.Gesendet von meinem JAZZ mit Tapatalk

author: Ijaz
author_rank: Contributor
timestamp: July 25, 2016, 06:27:46 pm
content: Hot melt glue. A drop of alcohol (IPA) will do the magic.

author: iXod
author_rank: Frequent Contributor
timestamp: July 26, 2016, 04:30:08 am
content: Quote from: Ijaz on July 25, 2016, 06:27:46 pmThe little-known secret of service: hot-melt just falls off in the presence of isopropyl. Quite a surprise.
schematic need - Page 1
Forum section: electronics / repair

author: mohandes
author_rank: Contributor
timestamp: July 13, 2016, 02:47:54 pm
content: hi any body have schematic inverter welder ZX7-200A??

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: July 15, 2016, 06:32:07 am
content: https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&cad=rja&uact=8&sqi=2&ved=0ahUKEwj1yOrw6_TNAhVLKMAKHb3xDcYQFgg0MAY&url=http%3A%2F%2Felektrotanya.com%2FEasyArc_zx7-200_igbt_inverter_welder.pdf%2Fdownload.html&usg=AFQjCNFXeshIsXQTPg0ysOxa4I44t-sK3A&bvm=bv.127178174,d.ZGg

author: mohandes
author_rank: Contributor
timestamp: July 15, 2016, 02:42:36 pm
content: Quote from: fluxcapacitor on July 15, 2016, 06:32:07 amhow can i register in this site??

author: JacobPilsen
author_rank: Regular Contributor
timestamp: July 15, 2016, 04:05:09 pm
content: Now you cansign upby completing an electrical test.Furthermore, now, you can register to the site if youfill up a simple electricity test.

author: retiredcaps
author_rank: Super Contributor
timestamp: July 15, 2016, 05:02:28 pm
content: On elektrotanya, you don't need an userid to download. I have used that site many times to download for free, but you are limited to 2 downloads per day and you have to have patience as the text below describes ...The preview is worse quality than the original pdf.This file is downloadable free of charge: ...processing...(You are not logged in, only 2 downloads per day possible for you.)

author: Ijaz
author_rank: Contributor
timestamp: July 25, 2016, 06:15:26 pm
content: Quote from: retiredcaps on July 15, 2016, 05:02:28 pmNice tip, one should just wait for the "processing" to change.
lcd monitor - inverter replacement - Page 1
Forum section: electronics / repair

author: unleashed666
author_rank: Newbie
timestamp: July 11, 2016, 06:22:52 pm
content: hello,ive got an old wacom monitor (branded as SMART podium ID422w)the inverter board has got a bit of damage on it ( burnt ic's) but it is still powering some of the backlights, ive attached the image of the screen belownow ive never really bothered fixing monitors as they are cheap to replace anyway, but this one i need to fix as i carnt afford to replace it.i know there are cheap universal inverter boards on ebay and wanted to ask for opions on them? are they any good? as i carnt find a wacom replacement board.also has anyone got any ideas on what could have caused this? i havnt taken the lcd apart yet so havnt checked the tubes for damage.all and any help would be appreciated

author: unleashed666
author_rank: Newbie
timestamp: July 12, 2016, 07:59:06 am
content: UPDATEive ordered a ccfl universal inverter $3and led backlight replacement kit $10wiring is the same on both. plan is to change inverter board to get it working (as that will be the easiest option) then i will replace with led kit later on when ive got more time------------------------i couldnt find any info online for the board so tested each wire on standby/on states, at least i know where each wire goes nowimage of voltage tests attached

author: unleashed666
author_rank: Newbie
timestamp: July 25, 2016, 04:44:10 pm
content: all fixed nowreplacement inverter arrived first and that got the backlight working again but did cause a bit of interferance which ment the pen cursor jittered a small amount but was still usable and wasnt too annoying.a few days later the led backlights arrived so old backlight got replaced and new leds work perfectly, no interferance at all and monitor colors look better and brighter so after a 4 week break i can finally start getting some work done again.
Philips pm 3215 channel behavior - Page 1
Forum section: electronics / repair

author: Stoes
author_rank: Newbie
timestamp: July 21, 2016, 09:50:03 pm
content: Hello all,I received a Philips pm 3215 repair which is acting kind of weird when hooking CH A & B up to the reference 1.2V square wave output of the scope.Whenever I hook it up, I see that the sq wave is kind of differentiating (see att.).When playing with the gain knob of that channel (which is also on the v/div knob) I manage to get a proper sq wave.But when changing the v/div of that channel, the sq wave is once again differentiating.This happens on CHA mostly, on CH B the dif behavoir is not happening all the time when turning the v/div knob.Also when wiggling the knob for v/div a little bit changes the differentiating sq wave.Anyone has an idea why I don't get the proper sq wave? Some kind of calibration?I don't want to unscrew the whole scope and look at these knobs from the inside if it can just be some sort of calibration on the front panel.This is the link to the service manual of the device:http://elektrotanya.com/philips_pm3215_u_sm.pdf/download.htmlThanks in advance!

author: tautech
author_rank: Super Contributor
timestamp: July 21, 2016, 10:30:15 pm
content: Welcome to the forumFirst thoughts would be dirty contacts on the attenuation switch.Are any of the problems seen with specific settings repeatable?If so that might suggest a damaged divider resistor just at those settings but you do have the other channels to reference/check against. Open her up and clean the switch contacts first, then go from there.

author: Kilrah
author_rank: Unknown
timestamp: July 21, 2016, 10:43:29 pm
content: +1, my 3214 has the same flaky contacts on the vertical settings.I'll really need to take it out any clean it up one day.

author: singapol
author_rank: Frequent Contributor
timestamp: July 22, 2016, 12:38:30 am
content: The shape of the square wave indicates high frequency peaking on ch. A. Test again by setting coupling to DC.If it's still the same then vertical amplifier AC gain needs to adjusted. See service manual for which trimpot to adjust and follow the procedures or steps to calibrate the vertical section/circuit. Yes, you need to open up the scope to get inside. Study the manual before doing this and good luck.

author: mzacharias
author_rank: Frequent Contributor
timestamp: July 23, 2016, 02:35:46 pm
content: Philips scopes of that era are pretty notorious for dirty switches. Difficult to get to, but they clean up OK - until next time that is...

author: Stoes
author_rank: Newbie
timestamp: July 25, 2016, 01:27:58 pm
content: Hello guys,cleaned out the pot's for both channels (A & B) and also (while everything was layout dismantled) also cleaned out the one for time axis knob. The contacts inside the pot were very dirty.The problem also was the disc that was mounted on the shaft of the knobs that weren't making contact any more with the little clips on the side.WD40 was my hero.mzacharias took me a few hours to dismantled everything..
Siemens Bluephone Payphone CT6D Repair - Page 1
Forum section: electronics / repair

author: DeBeng
author_rank: Newbie
timestamp: July 25, 2016, 09:04:43 am
content: Bit of a newbie to fixing things and I have no idea why my Bluephone isn't working.There is power coming into the phone but no power is going to the coin validator or screen.I've had a look at the board and found a dodgy diode (tested) and two inductors?The inductor marked L4 seems to have no continuity.I'm not sure what value the inductors are (if they are inductors) because they seem too big to be the value they say. Either that or I am just wrong at reading the value. The brand of the inductors is siemems.Pretty new to all this, so i'll be very happy for help!Thanks, Ben.

author: MAS3
author_rank: Regular Contributor
timestamp: July 25, 2016, 10:48:53 am
content: Hi.Those are inductors indeed.What's dodgy about the diode ?Does it short by any chance ?Didn't you notice the burnt traces surrounding the inductors (certainly L4) and the diode ?If a trace looks like that and an inductor is gone, you need to go and look for the cause of that.The inductor seems to have acted as a fuse here.Inspect those traces too.

author: DeBeng
author_rank: Newbie
timestamp: July 25, 2016, 12:33:23 pm
content: Yeah I saw the traces and the diode is dodgy because it does not allow any current through either way.

author: DeBeng
author_rank: Newbie
timestamp: July 25, 2016, 01:25:32 pm
content: just tried powering up the board and one side of the diode ranges from 1.1v - 5v while the other side ranges from -12 to -7 volts. So a replacement diode is definitely needed!
EMZ2510 IC datasheet or pinout info - Page 1
Forum section: electronics / repair

author: Ijaz
author_rank: Contributor
timestamp: July 25, 2016, 07:26:54 am
content: HiDuring the course of repairing a machine which has a rotary glass disc encoder, I have come across this IC EMZ2510-5147-B3. I was able to find EMZ2510-5147-A0 from another machine but that did not work.Apparently this IC is a sine wave to square wave conversion. Two channels work good and one is faulty. Anybody has data or at least pinouts of this IC ? I am sure B3 and A0 suffix are different as GND connection on both PCBs was on different pins of the ICs.Any help / hints will be appreciated.

author: amyk
author_rank: Super Contributor
timestamp: July 25, 2016, 10:59:07 am
content: Plenty of places where you can buy them, but no other information... weird.
Remote control for toy car factory defect? - Page 1
Forum section: electronics / repair

author: edy
author_rank: Super Contributor
timestamp: July 19, 2016, 01:13:08 pm
content: I bought a remote control car a few years ago from Staples. It was sitting on my shelf at work and never powered it up, I just liked the look as a display model.Anyways, my kids are old enough to play with it now so I brought it home and installed batteries. The car and remote both would power up fine but the remote had to be held very close to the car to work. Also, it would give intermittent signals... instead of continuous. For example, pressing throttle would make the car move but in short pulses rather than continuously. Same with steering... it would make the wheels jitter one direction or the other but not stay continuously in that direction.So I decided to open the remote up and was surprised to find this dog's breakfast on the PCB! This is frustrating and I am pretty sure it was failed manufacturing because:1. Bought it new in box (could have been a repackaged return)2. Never turned it on until a few days ago3. Gave no obvious indication of a failure, it just behaved like a weak batteryCould a 9V inserted reverse polarity have caused this much damage? I never smelled the magic smoke and don't recall ever inserting it backwards. The battery compartment does not protect against reverse insertion but even so would not the circuit have protection? I see a diode right on the input.QUESTIONS:1. Does this thing look beyond repair?2. How does it even turn on and function (albeit poorly) with this blown component?3. How do you go about even figuring out what belonged there?4. Could this have left the factory in China like this?5. Could I have been a complete and utter idiot and put a 9V in what was supposed to be a 2 AA compartment that was missing the conducting strip on the other end of the chamber to make them series? No, I can't imagine I could have been so stupid.

author: poot36
author_rank: Frequent Contributor
timestamp: July 24, 2016, 06:34:53 am
content: Clean all the black soot from the board and then measure all the components in that area for shorts. Does the toys box say what batterys it needs? Most of the smaller remote control cars do use just 2 AA batterys but not all.

author: amyk
author_rank: Super Contributor
timestamp: July 24, 2016, 02:38:05 pm
content: It looks like a tantalum cap blew
METRIX OX803 Oscilloscope Schematic wanted - Page 1
Forum section: electronics / repair

author: ElectricGuy
author_rank: Regular Contributor
timestamp: July 24, 2016, 01:28:31 am
content: HI;I'm loking for the METRIX OX803 Oscilloscope Schematic, anyone has it?

author: singapol
author_rank: Frequent Contributor
timestamp: July 24, 2016, 05:03:46 am
content: Sorry no such luck but the closest is ox710 below: Anyway general circuits are somewhat generic so should not be a problem except that it's mcu controlled.http://www.eserviceinfo.com/equipment_mfg/METRIX_35.htmlox803 user manual:http://uk.rs-online.com/web/p/analogue-oscilloscopes/2629653/
Where can I buy this Marquardt switch ? - Page 1
Forum section: electronics / repair

author: Sjokolade
author_rank: Regular Contributor
timestamp: July 24, 2016, 02:57:17 pm
content: I noticed my bikes brake light was not working - both wires on the Marquardt switch had come off.Marquardt has a online shop but can't find this 1022 type,https://www.marquardt-shop.com/products/switches/snap-action-switches.htmlAnyone know where I can source this switch ?

author: acbern
author_rank: Frequent Contributor
timestamp: July 24, 2016, 03:34:54 pm
content: I find the 1022.4501 in the shop. Not sure what problem you have finding it, try again.https://www.marquardt-shop.com/products/switches/snap-action-switches/1022.html

author: Sjokolade
author_rank: Regular Contributor
timestamp: July 24, 2016, 03:41:48 pm
content: That's not the same switch - mine has 2 wires and look different.

author: JFJ
author_rank: Regular Contributor
timestamp: July 24, 2016, 08:44:39 pm
content: The short part number (only 4-digits) suggests that the switch, cable and end connector is a custom assembly - made by Marquardt for your bike's manufacturer. If that is the case, then the switch is unlikely to be available on its own, and a new replacement assembly might only be available through the bike manufacturer's dealer network.Failing that, it's either obtain a used assembly (e.g. from a scrap yard or eBay), repair the one you have or modify some alternative switch to fit your bike.

author: pelule
author_rank: Frequent Contributor
timestamp: July 24, 2016, 08:52:52 pm
content: Sorry to say, but that 1022 is not the type, it is the date code: year 2010/week 22.Why not ask your bike manufacture for service part.PeLuLe

author: pelule
author_rank: Frequent Contributor
timestamp: July 24, 2016, 08:57:23 pm
content: Seems to be one of the "snap-action switches IP 67", may the 1056.0351https://www.marquardt-shop.com/en/products/switches/snap-action-switches/1055.htmlCheck the drawing for the measures.PeLuLe

author: Sjokolade
author_rank: Regular Contributor
timestamp: July 24, 2016, 09:31:28 pm
content: I think you're right JFJ - I will try to open it too see if it's possible to fix it.Quote from: pelule on July 24, 2016, 08:52:52 pmNo that can't be the date code - bike is from 2001 and I bought it in 2008 and this part has not been replaced by me earlier.I did check price for new part, with tax including postage ~82USD sadly - if I could find switch only I would be happy to pay € 2,85 hehe.Quote from: pelule on July 24, 2016, 08:57:23 pm1056.0351 has solder terminals and kind of inverted look compared to mine but youre right must be some IP 67 type.

author: klunkerbus
author_rank: Unknown
timestamp: July 25, 2016, 09:06:02 pm
content: It'd be sort of a hack job, but can you pick away at the potting compound enough that you could cut away some of the remaining wire insulation and tack on wires with some solder? Then perhaps apply a lot of silicone sealant over that end of the switch.For the wires to break like that, they must have been flexing right at the switch. You'll want to eliminate that wire movement at the switch after it is repaired.
Hameg 1005 Scope not triggering - Page 1
Forum section: electronics / repair

author: Colin1256
author_rank: Newbie
timestamp: July 28, 2016, 05:45:03 pm
content: Dear all,I've purchased an old Hameg 1005 (100 MHz Scope) because it reminds me of my days at university.It's fairly beaten up, but I'm trying to restore it to working order.It is generally working fine; I have already been into it to replace some broken caps on the Channel 3 input, so that is taken care of. Next, I'd like to get it to trigger again. I am unable to get either timebase to trigger on anything but line. If leave it on Auto-Trigger, it won't lock in at all, if I try to set the trigger level manually, it won't lock in.Any ideas?Thanks a lot in advance!Colin

author: singapol
author_rank: Frequent Contributor
timestamp: July 28, 2016, 07:23:41 pm
content: See service manual for relevant info. If you have no electronics experience please asked someone who can repair as there are high voltages in scope that can kill.Check pcb for cold solder joints as in:Related topic:https://www.eevblog.com/forum/testgear/hm1005-repair-12v-rail-unstable/Oscilloscope troushooting :www.sphere.bc.ca/test/tek-parts/troubleshooting-scopes.pdfHameg 1005 user/service manual:https://cdn.rohde-schwarz.com/hameg-archive/HM1005_englisch.pdf

author: oldway
author_rank: Super Contributor
timestamp: July 28, 2016, 07:40:10 pm
content: First, welcome on the forum.You must check the following:- Check voltages and ripples of the power supplies. (check also the -5V !)- Check for cold solder joints, particularly the mass solders (very common problem)- Clean the switches with contact cleaner: I recommend KF F2 special contacts.Another common problem: an interrupted diode of the rectifier bridges. The ripple before stabilization is then 50Hz instead of 100 Hz.After this, check if you can trigger your scope with external trigger.

author: Colin1256
author_rank: Newbie
timestamp: July 29, 2016, 06:12:09 am
content: Guys, thank you!I did already check the supply rails (though just with a DVM, not with a scope). The voltages were certainly there and pretty much spot-on. Obviously, I didn't check for ripple though.I will let you know what I find.Thanks!Cheers,Colin

author: oldway
author_rank: Super Contributor
timestamp: July 29, 2016, 01:50:50 pm
content: Quote from: Colin1256 on July 29, 2016, 06:12:09 amWhy not ? You can measure ripple with your multimeter on AC scale, you don't need another oscilloscope to do that. (but to repair a trigger fault of your HM1005, you will !)

author: Colin1256
author_rank: Newbie
timestamp: July 29, 2016, 03:29:24 pm
content: Quite honestly, I just didn't think of it.I checked that the voltage rails were there, and my 5 1/2 Digit Multimeter showed them to be within spec and also, they didn't move at all... so it didn't occur to me to look for any ripple on the rails.I'll have a look this Sunday.Cheers,Colin
Faulty MacBook Air 2010 - not charging. - Page 1
Forum section: electronics / repair

author: JJalling
author_rank: Unknown
timestamp: July 19, 2016, 06:40:25 pm
content: Hi all,I have just found my old faulty MacBook Air, from the bottom of a drawer. I thought I would give it a go on fixing it.The problem is that the computer wont accept the charger, if the internal battery is connected. I can confirm that the battery isn't faulty, as it is working in another computer.If I open the computer and disconnect the battery, the computer accepts the charger and powers on.I have also noticed, that when the charger is disconnected and the battery is connected, I can roughly measure the battery voltage on the external charging connector.Here is what I think is the fault (please see this schematic, page 50, on the top).https://eevblog.jalling.net/820-2796.pdfIf I measures Q7080, it is shorted between drain and source. D-S on Q7085 measures ~5MOhm.Should I just replace Q7080 or is there anything else I should look for?Thanks,bR Jonas

author: jh15
author_rank: Frequent Contributor
timestamp: July 20, 2016, 02:23:56 am
content: Where can I get Apple schematics like that for the Imacs?

author: jh15
author_rank: Frequent Contributor
timestamp: July 20, 2016, 03:06:51 am
content: I was going to mention him, but thought he would be reticent about sharing at this time.Sure took a long time to d/l all his videos last week.I mostly refer his videos to friends looking for computers and reference the rotten apple videos and what to expect once you buy such a 'well made and durable product'.Then again, I would not want to support Windows either.I just show them my Linux stuff and they run away, no worries whatsoever:)

author: kripton2035
author_rank: Super Contributor
timestamp: July 20, 2016, 05:42:42 am
content: Quote from: edavid on July 20, 2016, 03:47:26 ammacbook air 2010 are vintage, so no more part available from Apple.

author: kripton2035
author_rank: Super Contributor
timestamp: July 20, 2016, 05:47:27 am
content: Quote from: jh15 on July 20, 2016, 02:23:56 amyou need the model of your imac aka Axxxx then a google search leads to something like this :http://kythuatphancung.vn/download/apple-imac-27-a1312-sch-k23-mlb-schematics.html

author: JJalling
author_rank: Unknown
timestamp: July 20, 2016, 03:13:12 pm
content: Quote from: JJalling on July 19, 2016, 06:40:25 pmI removed Q7080 and replaced it with another (temporary) FET. Now the computer works as intended, so I will order the correct FET and fix it.BR Jonas

author: Rasz
author_rank: Super Contributor
timestamp: July 21, 2016, 06:16:02 pm
content: Quote from: blueskull on July 20, 2016, 02:48:54 amlol dont
D620 dc jack testing - Page 1
Forum section: electronics / repair

author: mar6
author_rank: Newbie
timestamp: July 20, 2016, 09:50:07 am
content: Hello and sorry for bad english language.I would like to test my non-working Dell latitude D620 DC jack, but i dont know how to do it.I tested power adapter with multimeter and it is ok. I have not much experience in laptop testing.I made picture of dc jack.http://i63.tinypic.com/mh681e.jpgI hope that someone can show me where i must put test leads on that jack.Thank You!

author: WaveFunction
author_rank: Newbie
timestamp: July 20, 2016, 01:21:31 pm
content: So the notebook does not turn on at all?The attached picture shows the pinout for that DC jack.I edited your picture to show where to put your multimeter probes. You should put your probes on the motherboard so you know the voltage is getting from the DC jack to the motherboard.

author: mar6
author_rank: Newbie
timestamp: July 21, 2016, 11:49:35 am
content: Thank You for very useful info.I got it tested, but no voltage. This means that it could be broken jack or any other component ?Yes, notebook does no turn on at all.

author: WaveFunction
author_rank: Newbie
timestamp: July 21, 2016, 01:29:51 pm
content: Some possibilities:1) Short circuit on motherboard -- If there is a short circuit, then the AC adapter will turn off when you plug it into the jack. Does the AC adapter have a light? If so, make sure it stays on when you plug it into the jack. You can also test the voltage of the adapter before plugging it in. Then test it again after unplugging it from the jack. Make sure it is still 19V (i.e. it didn't shut off to protect itself).2) Bad AC adapter -- Even if you read 19V, the adapter can still fail under load. It would be helpful to try a different adapter or try this adapter on another Dell notebook. Just to be sure.3) Bad solder joints -- You can remove the motherboard and inspect the solder joints. Wiggle the jack and watch if the joints move. Look carefully. Sometimes the whole solder joint (and pad) lifts off the board a tiny tiny distance. It's very hard to see. The pins may need to be resoldered. If you have soldering skills, you can resolder the jack just in case. If any pads are damaged, then that makes resoldering more difficult (the missing pads must be replaced with wires).4) Bad jack -- There might be something wrong inside the DC jack. If so, it will have to be replaced.
Where to find Tektronix TDS/TPS scope feet? - Page 1
Forum section: electronics / repair

author: JPortici
author_rank: Super Contributor
timestamp: July 21, 2016, 11:46:31 am
content: Not really about repair.. more like mantaining. The TPS2014 at work has a missing feet and sometimes i would like to replace itTek part number: 348-1703-00I looked at the usual websites that carries tek parts (spheres and qservice) but i wasn't able to find those.I know ishoulddrop an email to tektronix and ask them, i think there is a good chance they still have the parts in stock but i wanted to have a rough estimate on how much it would cost me (i wouldn't pair more than a couple of euros. scope works and we have a piece of rubber in place for the missing leg, to keep it inclined. It's more a desire to have it also in good cosmetic condition