hybridfree/eevblog-posts huggingface dataset:
DDR2 pc memory diagram - Page 1
Forum section: electronics / repair

author: SAUL BRITTO
author_rank: Frequent Contributor
timestamp: April 25, 2016, 12:34:44 am
content: Has any one a diagram to a ddr2 pc memory? I need to know where are the clock pins and other things.

author: tesla500
author_rank: Regular Contributor
timestamp: April 25, 2016, 02:30:07 am
content: http://www.interfacebus.com/Memory_Module_240Pin_nonEEC_SDRAM_PinOut.html

author: John_ITIC
author_rank: Frequent Contributor
timestamp: April 25, 2016, 07:03:00 am
content: With "PC Memory", I would assume you are referring to a DIMM of SO-DIMM module. See below linkshttps://www.google.com/?gws_rd=ssl#q=jedec+ddr2+dimm+specification

author: amyk
author_rank: Super Contributor
timestamp: April 25, 2016, 10:11:36 am
content: If you dig around the JEDEC site a bit you'll also find BOMs and PCB layouts.
Identitying Zener Diodes on Futaba VFD from Advantest R3752B Network Analyzer - Page 1
Forum section: electronics / repair

author: Ondre
author_rank: Unknown
timestamp: April 24, 2016, 03:08:19 pm
content: Hi!I'm currently repairing an Advantest R3752B Network Analyzer which has a bad PSU and a bad frontpanel display. The power supply is almost fixed - just a bunch of dry caps.The VFD, as you can see on the picture, had a bit of a rough time. The board is supplied with 5V for the logic and 12V for the HV supply.Since R48 and R49 were burnt completely, I replaced them temporarily, connected the power (with limited current on the 12V line) and they immediately started smoking again as I increased the current. So I figured that the two nearby driver ICs were probably toastet. I've bought a few SN755701FTs from a dubious source on Amazon and replaced them as well. Current drawn on the 12V line is now approx. 2A. The two driver ICs are getting a bit hit and the display is still dark. I examined the HV supply a bit and found two z-diodes (ZD1 and ZD3) that were shorted and one (ZD4) that has an implausible voltage.Here's where I need a bit of your help. I have no idea what value z-diodes are supposed to be used here.ZD3 has a color code (yellow, yellow, green) which I couldn't find anywhere.ZD1 is probably 9.3V, but I'm not sure.ZD4 has written 12 on it, but has a zener voltage of about 3.8V. Is that correct?It would be great if someone could clue me up on how to decode the readings on these diodes.
Rohde & Schwarz Signal Gerator SML-01  - Page 1
Forum section: electronics / repair

author: WaterMM
author_rank: Newbie
timestamp: April 20, 2016, 06:28:51 am
content: Hi All, I'm new here.I have 2 units SML-01 need repair.The failure as below:Unit 11) Internal cal failed Harm Filter & Level Preset2) Selftest failed :Err 110, O/P unleveled Failed selftestUnit 21) Internal cal failed Harm Filter & Level Preset2) Selftest Err 110, O/P unleveled Failed selftest ,Err -313 Cal memory lost : Level PresetErr -313 Cal memory lost : Harmonic filterI've perform internal cal according to the user manual, but it still the same.I suspect for the flash cal memory lost ? Any idea and advise from your experience. Thank you.

author: Smith
author_rank: Frequent Contributor
timestamp: April 20, 2016, 02:39:35 pm
content: Welcome,Some more info would be nice. Have you bought both broken? Do you know what happened to the units? I reckon the output could be blown/defective, or something like calibration. I don't think the calibration is an issue, and maybe it even failed on unit 2 after the unit was broken.You could take a look here:https://www.eevblog.com/forum/repair/rohde-schwarz-signal-gerator-sml-01-dead-needs-repair/I think it would be wise to check voltages first. Also, does the unit work besides the errors/warnings?

author: HighVoltage
author_rank: Super Contributor
timestamp: April 22, 2016, 03:41:48 pm
content: A few month ago, I repaired a broken one and it all came down to the power supply circuit and bad electrolytic caps.https://www.eevblog.com/forum/repair/rohde-schwarz-signal-gerator-sml-01-dead-needs-repair/msg843706/#msg843706The repair was easier than I had expected.You should start at all the rail voltages.
TDS 744A - Does it have a battery or NVRAM chip that needs to be replaced? - Page 1
Forum section: electronics / repair

author: AndersJ
author_rank: Frequent Contributor
timestamp: April 21, 2016, 08:38:16 am
content: There have been lengthy discussions in this forum concerningbattery and/or NVRAM replacement in older Tektronix scopes.Does anyone know if this is an issue for the TDS 744A?

author: vaualbus
author_rank: Frequent Contributor
timestamp: April 21, 2016, 09:29:58 am
content: All the nvram fail after 10 years so should bevxhanged. Luckly i think maxim have this nvram in free sample.

author: AndersJ
author_rank: Frequent Contributor
timestamp: April 21, 2016, 09:47:23 am
content: Please let me clarify my question.Does anyone know if the TDS 744A uses:* Discrete batteries for RAM content backup?* RAM chips with built in batteries?* Other batteries that need to be replaced?In other words: Does the scope have batteries in any form?

author: Andy Watson
author_rank: Super Contributor
timestamp: April 21, 2016, 10:22:00 am
content: Service manual (page 1-12) says "Yes".Quotehttp://w140.com/tekwiki/wiki/TDS744

author: ArcticGeek
author_rank: Regular Contributor
timestamp: April 21, 2016, 04:59:40 pm
content: Yes, the TDS744A definitely depends on 2 batteries to hold configuration data and waveform data.There is a DS1486 RTC part that has an internal battery - this holds the configuration data such as options and current state of the signal pass compensation. There is also and NVRAM part that has an internal battery that holds the waveforms that you save to the reference waveforms.These batteries are not replaceable though, they are internal to the encapsulated part.Does that answer your question?

author: AndersJ
author_rank: Frequent Contributor
timestamp: April 21, 2016, 05:05:28 pm
content: Yes, that is a clear and concise answer.Thank you.

author: nctnico
author_rank: Super Contributor
timestamp: April 21, 2016, 08:54:16 pm
content: Quote from: AndersJ on April 21, 2016, 05:05:28 pmFrom my own experience these batteries last much longer than their specified lifetime. Remember there is also a temperature range so if the scope has been sitting at room temperature the battery life will be much longer.Secondly: several people have been able to mill the package open and replace the battery.
Seven Segment Displays blinking - Page 1
Forum section: electronics / repair

author: EEVaditya
author_rank: Regular Contributor
timestamp: April 19, 2016, 11:26:29 am
content: Hello,I have Common Anode Seven Segment displays in combination with 2N2222A Transistor and 74LS47. They are blinking at particular setting for e.g. at 100mA but not at 160mA and above.Why is it so? Please guide.

author: CJay
author_rank: Super Contributor
timestamp: April 19, 2016, 11:46:01 am
content: Quote from: EEVaditya on April 19, 2016, 11:26:29 amHow are you limiting the current?I.E. they are trying to draw more than the current limit you've set and your PSU is dropping the voltage below their forward voltage requirement?

author: EEVaditya
author_rank: Regular Contributor
timestamp: April 20, 2016, 03:01:01 pm
content: Does the tolerance that is 1% or 5% of resistor for seven segment displays make any difference?

author: Kleinstein
author_rank: Super Contributor
timestamp: April 21, 2016, 03:05:05 pm
content: Usually the displays are specified at something like 10 mA per segment. So 100-160 mA is a rather high current. Also the 74ls47 does not provide that much current. How is the current changed ? - usually it's a resistor per segment - so not much to change, as the 74ls47 like a rather constant supply.Tolerance of the resistors does not really matter, as the LEDs have tolerances as well.
Maintenance PM software suggestions - Page 1
Forum section: electronics / repair

author: Kevin11790
author_rank: Newbie
timestamp: April 16, 2016, 11:57:36 am
content: Any suggestions on some good maintenance PM software out there? Anything cheap and not too fancy, but gets the job done well? I work for maintenance in a factory and am looking for sometime a little better for tracking a scheduling PMs.Sent from my Nexus 6 using Tapatalk

author: FrankE
author_rank: Regular Contributor
timestamp: April 21, 2016, 01:59:11 pm
content: I'm not sure if Shire Systems is stiill going but that was cheap and good enough for some key national infrastructure I was responsible for.SAP PM &MM is the CMMS I have seen most used, usually because in thos organisations it's tied into financials.
Repair suggestions for cracked Fluke 87V screen protector - Page 1
Forum section: electronics / repair

author: nikkoderic
author_rank: Contributor
timestamp: April 14, 2016, 04:35:02 pm
content: Hi community!I'm a Fluke fanand I'm very glad to have a Fluke 87V multimeter as an ECE undergraduate student, so when I realized that I cracked the screen protector of my multimeter after I cleaned it I got very. I just want to ask if there's anything that I can do to fix this (or make it less visible) without buying an entire front case replacement. I'm from Philippines so buying a replacement would be very hard and expensive (almost impossible) for me.I thought Fluke multimeters are almost indestructible.Thanks for your help. =)

author: Jonny
author_rank: Regular Contributor
timestamp: April 16, 2016, 09:53:25 am
content: What about an automotive glass windshield repair kit? It's OCA UV cured resin you force into the crack. I'd guess about $15 at an auto parts shop.

author: stj
author_rank: Super Contributor
timestamp: April 17, 2016, 04:42:52 am
content: if the print is on the case, not backprinted on the clear section, i would be tempted to ask a glass shop to make a 3mm hardened glass replacement wih rounded corners and bevelled edgesthe piece is so small that they could use a bit of scrap from the bin - so you would only be paying for the cutting and grinding.the car windshield stuff wont work, they have to put a small vac chamber over the glass and suck the air out to use that resin.

author: Shock
author_rank: Super Contributor
timestamp: April 17, 2016, 06:16:04 pm
content: Be contacting the repair agents close to you to see if it's covered by warranty.

author: nikkoderic
author_rank: Contributor
timestamp: April 19, 2016, 06:04:29 pm
content: Thanks for suggestions! I'll give the windshield repair a try since we actually have a vacuum chamber. Having someone to recreate the screen protector is actually a very good idea. I'll definitely do it if the windshield repair yield unsatisfactory result or we cant, after all. The multi meter is actually a second hand one and sold to me without manual and warranty "documents" so I don't think it can still be repaired under warranty.Thanks again! =D

author: SeanB
author_rank: Super Contributor
timestamp: April 20, 2016, 07:12:58 pm
content: Have a look at the small kits that are used for repair "on the go" as they include a small suction cup that is fitted to the syringe applicator and which is pulled back to make a pressure pulse of liquid that is forced into the clean crack to fill it before you do the UV cure. On glass it is almost invisible after repair.

author: JFJ
author_rank: Regular Contributor
timestamp: April 20, 2016, 09:41:54 pm
content: There was a usedFluke 87V top caseon eBay, a few weeks ago, with a crack in the same place. If the cracks are due to an inherent weakness in the case design, then it may be worth reporting it to Fluke.
MiniPro TL866 Firmware Upgraded and broken Fake device - Page 1
Forum section: electronics / repair

author: Mikek400
author_rank: Regular Contributor
timestamp: April 20, 2016, 06:31:06 am
content: Got a Mini Pro today. Installed software and software told me to upgrade firmware.After upgrading got error and then application gave me this message (see pic below)This sucks.. Been waiting for this thing for 2 weeks and breaks in 5 mins.

author: Kilrah
author_rank: Unknown
timestamp: April 20, 2016, 07:54:14 am
content: Welp... buy a real one next time?

author: Mikek400
author_rank: Regular Contributor
timestamp: April 20, 2016, 10:54:58 am
content: I thought it was a real one... Box and description said it was.. Heck even looks the same on the inside as the one Dave tore down.The application erased the firmware on the device so I am going to try to reprogram the PIC on the board.

author: macboy
author_rank: Super Contributor
timestamp: April 20, 2016, 02:29:10 pm
content: Quote from: Mikek400 on April 20, 2016, 10:54:58 amI've programmed mine with a PicKit3. The PCB has holes for the standard ICSP header inside. I didn't even solder a proper header, I just press-fitted male header pins into the PCB holes while programming. Good luck.

author: Mikek400
author_rank: Regular Contributor
timestamp: April 20, 2016, 04:57:38 pm
content: I found a PDF and Application from radioman's PDF and software in the blog post about this programmer.https://github.com/radiomanV/TL866Reprogrammed it using a parallel port,some resistors and the attached pdf and software.I attached the PDF files and the application below for reference.
Sony pvm crt monitor problem - Page 1
Forum section: electronics / repair

author: aluqard89
author_rank: Contributor
timestamp: April 19, 2016, 06:07:22 pm
content: Hello !I got a huge problem with my CRT monitor PVM-14L4 as you can see in the video i linked. It shuts off almost immediately.anyone got a clue?https://youtu.be/Npwx5VVlpiM

author: Shock
author_rank: Super Contributor
timestamp: April 20, 2016, 04:27:32 am
content: http://www.repairfaq.org/sam/tvfaq.htm
Fluke 120 serial number DMxxxxxxx - Page 1
Forum section: electronics / repair

author: yaromka
author_rank: Newbie
timestamp: April 17, 2016, 02:27:18 pm
content: Hello! help to identify the serial number Fluke125, tell me please is it possible to read using the opto cable or display on the device. A sticker with the number on the back was lost...maybe someone knows about additional ones inside the instrument? Thanks.

author: yaromka
author_rank: Newbie
timestamp: April 18, 2016, 06:39:57 am
content: I tried using the terminal program to transmit the request "*IDN" the answer is "1" and the request"ID" answer "FLUKE 125;V03.04;2008-06-10;English, French,German,Dutch,Spanish, Portugese,Italian, Japanese,Korean,Chinese". But the serial number was not displayed...

author: Psi
author_rank: Super Contributor
timestamp: April 18, 2016, 08:02:10 am
content: I believe fluke meters that have been repaired (replacement pcb) always show as s/n = 1Stupid, but true.

author: crispy_tofu
author_rank: Super Contributor
timestamp: April 18, 2016, 11:39:17 am
content: This happened to usertony3das well for his Fluke 287:https://www.eevblog.com/forum/repair/i-don't-know-about-fluke!/

author: yaromka
author_rank: Newbie
timestamp: April 18, 2016, 04:27:05 pm
content: Hello. Thanks for the hint. Really strange.. how to get update because installation pack require the S/N?
Repairing the Panasonic AG-MD835 S-VHS VCR with bearding and flickering symptoms - Page 1
Forum section: electronics / repair

author: NTSCpal
author_rank: Newbie
timestamp: April 18, 2016, 07:15:25 am
content: Hi all,I was donated a Panasonic AG-MD835 S-VHS VCR that has not been used for ten years at least and only has about thirty hours of drum use. On arrival, the unit was dead but was so because it was in a shutdown mode caused by a jammed mechanism. The tape transport and mechanism have been cleaned and made working again after realignment. Playback of pre-recorded tapes (i.e. tapes recorded on other VCRs) that are known to be in good condition shows small amounts of dropouts and bearding during luminance transitions e.g. black to white horizontally. Recordings made by the unit itself show more severe bearding on playback, almost enough to cause loss of sync. For both pre-recorded and self-recorded tapes, the picture would have flickering brightened white stripes fully across the screen and upon imagery with very high detail, the picture dims slightly.The rotary drum is clean and has no physical damage. There are no visual signs of capacitor failure, however there are surface mount electrolytics (SMEs) on the video and audio processing PCBs.I do electronics repairs part-time but this unit is the first unit for me to deal with SMEs. Can some light be shed on this repair please? Thanks in advance.
Identifying a mosfet/switching regulator? I()R 227H - Page 1
Forum section: electronics / repair

author: chaseadam
author_rank: Contributor
timestamp: April 16, 2016, 02:38:01 pm
content: I let the magic smoke out of a few packages on my Triton Charger. I believe this was due to a mistaken short which would have dumped ~20A through these (possibly at a -36v potential), I am am not sure. I would appreciate if anyone can point me in the direction of identifying the function and a datasheet.The text I could see was I()R 227H

author: sdk.61
author_rank: Contributor
timestamp: April 16, 2016, 03:43:25 pm
content: Very good

author: ruffy91
author_rank: Regular Contributor
timestamp: April 16, 2016, 03:48:36 pm
content: You are out of luck. It's an International Rectifier Mosfet in SO8. 227H is the datecode. The type is on the 2nd line.

author: chaseadam
author_rank: Contributor
timestamp: April 16, 2016, 05:16:54 pm
content: The second line read either I6L0 or J6L0. Last two digits on the third line are 24. Looks like the third line is the ticket and that is toast unless someone can put the remaining information together to figure it out.

author: siggi
author_rank: Regular Contributor
timestamp: April 16, 2016, 07:45:44 pm
content: Looks like you're not the first person to fry one of those. Looks like the same thing:www.rcgroups.com/forums/showthread.php?t=268510Sent from my iPad using Tapatalk

author: wraper
author_rank: Unknown
timestamp: April 16, 2016, 08:08:42 pm
content: IRF7424

author: chaseadam
author_rank: Contributor
timestamp: April 18, 2016, 01:49:33 am
content: Thanks for the pointer! Didn't even occur to me to check the RC forums for similar repair attempts!
Help on ID of TO-220 device in a HP8648A - Page 1
Forum section: electronics / repair

author: deepskyridge
author_rank: Regular Contributor
timestamp: April 16, 2016, 05:48:52 pm
content: I am trying to repair a HP8648A, Two devices on the motherboard are marked:55-0645IR94237K 4ZIt is a TO-220 package.I have tried repeated searches for this with no luck.ThanksGary

author: edavid
author_rank: Super Contributor
timestamp: April 16, 2016, 05:57:03 pm
content: The HP part number is 1855-0645, which is a BUZ11...

author: deepskyridge
author_rank: Regular Contributor
timestamp: April 16, 2016, 07:08:25 pm
content: Thanks, that helps.Gary
need a schematic and/or manual for Simpson 460 series 2 - Page 1
Forum section: electronics / repair

author: gadget73
author_rank: Regular Contributor
timestamp: January 03, 2016, 02:35:28 am
content: As the title says, I need a manual or schematic for a Simpson 460 series 2 digital voltmeter. This one has some problems that I can't chase down without the map. I found one for a later 460 series, but its a very different meter.Failing that, does anyone know how close a Simpson 360 portable digital is to the 460 bench meter?Yes I know its an old piece of junk. Its just a rainy day sort of project. Either it needs to work, or it needs to go away. Figure I'll give it a go first, otherwise its a project box for something.

author: trog1058
author_rank: Newbie
timestamp: April 18, 2016, 05:24:28 am
content: http://simpson260.com/downloads/downloads-2.htmhope this helps
Help Please - Page 1
Forum section: electronics / repair

author: zl3lfc
author_rank: Newbie
timestamp: April 16, 2016, 04:46:09 am
content: Hi David, I wonder if you could help me with a problem i have ? I used to have a little dog that loved to eat Remote,s LOL and because of this i am left with a large number of TV Digi Boxes that have no Remote Controllers to operate them, the Remotes are needed to get into the setup menu and also tune the TV Digi boxes inWhat i was wondering is would you know how to make a controller that could be used with these boxes as it seems a waste to throw them away i am not too bad at electronics having started in the hobby at an early age 4 LOL fixing the old B&W Tv,s with my Dad i have been unable to get a universal remote to work but was wondering if there is any way to work out what type of Code the Remote would need to send or if there is any Hack i could do to the TV Digibox to allow me to use a Universal remote with them or even build a Remote tx onto an Arduino board or even use a pic controller with an infra red diode to send the data to the TV Digi Box..Any Help or any ideas would be very much appreciated.Kind RegardsSteve JonesLiverpool UK

author: Psi
author_rank: Super Contributor
timestamp: April 16, 2016, 04:55:04 am
content: We have no idea what a "TV Digi Boxes" are without a module number

author: zl3lfc
author_rank: Newbie
timestamp: April 16, 2016, 05:18:32 am
content: Dion STB1AW11 set top box

author: Psi
author_rank: Super Contributor
timestamp: April 16, 2016, 07:02:28 am
content: That's a pretty obscure device, im not surprised your having issues finding a uni-remote that will work on it.Have you tried a harmony remote set to Jiuzhoutech STB1AW09+that is the closest i can find.

author: JFJ
author_rank: Regular Contributor
timestamp: April 16, 2016, 12:51:02 pm
content: Quote from: zl3lfc on April 16, 2016, 04:46:09 amIt may work out cheaper to just buy an original or a replacement remote control on eBay:http://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=Dion+%28STB1AW11%2C+STB2AW11%29&_sop=15
The device Zoom H1, what type of switch is this? - Page 1
Forum section: electronics / repair

author: CircuitryLab
author_rank: Newbie
timestamp: April 16, 2016, 09:57:25 am
content: Searching for the service manual for Zoom H1. I cannot seem to find it.The power button/switch, what type of switch is this?To turn on the device, you slide the switch to the power on and hold it for few seconds, then it will turn on. When you let go of the switch, it return to neutral(center) position.

author: SeanB
author_rank: Super Contributor
timestamp: April 16, 2016, 10:38:21 am
content: Spring biased slide switch.
Programming and service manual for Alcatel Office 4200E PBX - Page 1
Forum section: electronics / repair

author: CHexclaim
author_rank: Regular Contributor
timestamp: April 15, 2016, 06:16:30 pm
content: Hello everyone,We have an Alcatel Office 4200E PBX that has been working fine for some years but last week it started with some weird behavior. First the OGM sounded all messed and yesterday it stopped working. After some effort we managed to bring it back to life but it lost all programming (although the backup battery is ok) and some it is unstable.I am figuring out that there may be a power supply problem as when I plug all cards in the unit fails to boot but with one of the cards out it works.I would like to have the service manual in hand before touching it so that I can proceed properly.Any comment is greatly appreciated and if someone can lead me to the programming and service manual of the unit that will be great.Thanks, Charlie.

author: SeanB
author_rank: Super Contributor
timestamp: April 15, 2016, 06:27:10 pm
content: Pull power supply and check the DC DC converter on it, there should be a whole load of rather sick electrolytic capacitors on it. Likely the 5V rail is failing.
Pls Help me find Manual Panasonic VP-7782a Audio Analyser - Page 1
Forum section: electronics / repair

author: chihaxinh
author_rank: Regular Contributor
timestamp: April 19, 2016, 02:04:27 am
content: Dear EverybodyI Have one Panasonic VP-7782a Audio Analyser but dont have Manual . Any one have User Guide or User Manual pls help me or guide me howto using , basic setup , basic mearsurement .Thank you so much !
Bluetooth USB Dongle And Headset - Connection Issues? - Page 1
Forum section: electronics / repair

author: Ryan T
author_rank: Newbie
timestamp: April 16, 2016, 11:00:59 am
content: I recently got a wireless headphone from bluetooth. This meant i had to get a Bluetooth USB dongle. This is the equipment. Simple right?Well the trouble is, i think the headphones are have range or connection issues. When the dongle finds the headphones, the sound doesn't come through unless the side of the headphones that detects the signal is pointed at it, no matter how far the headphones are. But if the headphones are turned to the other side, no matter how close it it, the headphones can't detect the sound.Another clue is when i put something in front of the dongle, the sound cuts out on the headphones (sometimes the audio aka my music has to skip to catch up) and when i jiggle the dongle around the sound starts to come clear from some angles, but as soon as i release the pressure, the sounds gone.Any idea which appliance is the faulty one, what's the problem and why?CheersRyan Tillotson
Tek 485 - how to test power transformer and rectifier board out of circuit - Page 1
Forum section: electronics / repair

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: April 14, 2016, 04:30:40 am
content: My Tek 485 was working fine till a couple of weeks ago when in use for some diagnostics. It was on standby when screen display suddenly contracted to a small and very fuzzy square (perhaps 1" by 1"). Then completely blank. At this stage the balance node was going positive during inverter start-up suggesting I had no 3KV supply - all the other power supplies checked out fine. Couldn't test -2950V supply at that stage (now have an HV probe for that) but HV current sense (TP1958) indicated a short. Subsequently, however, all the DC supplies went out across the board. All I have now is the warning neon on the Inverter board flashing (but none of the usual ticking or neon flashes from the power section of the Horizontal Amp board), regular start pulses at TP1835, and Q1900 & Q1902 working fine. Power looks to be getting to the T1960 primary but perhaps nothing out the other side. Inverter is trying to start up but not succeeding.I've repaired this Tek a few times (new U1600 6x multiplier a few years ago). Several resistor/cap replacements to fix DC supply issues. But I figured at this stage I needed to check what happening at the power board and particularly the T1960 transformer - which is a fair bit of dissection. Nothing obvious now I have it out, but would appreciate advice as to how best to test the transformer and rectifier circuits while it's out. The caps and resistors on the rectifier board check out OK but there's a couple of 12kV diodes there that I likely need to test. There's no obvious sign of breaks in any of the transformer primary or secondary circuits, but that's a very limited test and unlikely to tell me about shorts. I have a Variac, so can gently power it up and look for output on the HV and low voltage lines out (very carefully!), but not sure whether that's wise with no load on the transformer output. Grateful advice.Re the 6x multiplier, it looks fine with no signs of cracking or shorting. I think I recall someone testing this by feeding in a low voltage (25V or so) square wave and testing output at far end. Is that the way to go?Keen to try and get this debugged out of circuit as far as possible as it's a big job to get it out and then reinstall, only to find it's still not working. Really need to know it is doing its job before I can look for any other points of failure.

author: tggzzz
author_rank: Super Contributor
timestamp: April 14, 2016, 10:23:12 am
content: Have you checked the Yahoo! TekScope group's archive?https://groups.yahoo.com/neo/groups/TekScopes/info

author: tautech
author_rank: Super Contributor
timestamp: April 14, 2016, 10:28:06 am
content: Checked this?http://www.sphere.bc.ca/test/tek-parts/troubleshooting-scopes.pdfTroubleshooting chart in the service manual?
Help identify this DC connector type? - Page 1
Forum section: electronics / repair

author: clickykbd
author_rank: Newbie
timestamp: February 22, 2016, 01:35:54 am
content: Hi. Help identify this connector?I need to put together a 5v 6A PSU for a piece of gear I nabbed that was too cheap to include one. (and the rare factory ones out there are $60+).I miraculously got another ebay seller to send me some photos of his PSU connector.Similar to molex stuff, but I'm not quite sure...The item (and context photo of the connector is on this listing):http://www.ebay.com/itm/Blackmagic-Workgroup-VideoHub-HD-SD-SDI-Routing-Switcher-12-x-24-/201521561310?hash=item2eeb9efede:g:PZIAAMXQxU9R8JvNDetailed photos of connector attached to post.Thanks,Ryan (clickykbd)

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 22, 2016, 01:41:42 am
content: At minimum, measure the PITCH (the distance between the pins) so that we have some frame of reference.Frankly, it looks like a very ordinary, jelly-bean connector to me. Something cost a few cents.The biggest problem will be finding exactly the right SIZE because they come in a variety of sizes.

author: rx8pilot
author_rank: Super Contributor
timestamp: February 22, 2016, 02:18:09 am
content: If it comes from Black Magic, it is cheap and common. They only deal with the cheapest and most common thing they can possibly get away with.

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 22, 2016, 02:25:40 am
content: Looks like a rather old (and obsolete) product. I've never seen any BMD gear with that power connector.All their current gear uses a beefy "DB" style 3-pin connector, and even that is going away in favor of built-in power supplies with industry-standard universal-voltage IEC power inlets.

author: rich
author_rank: Frequent Contributor
timestamp: February 22, 2016, 02:58:50 am
content: They look similar to the XT60 battery connectors, but I think those might have an extra keyway.

author: Leuams
author_rank: Contributor
timestamp: February 22, 2016, 05:05:37 am
content: Looks like a generic Molex connector. Maybe something like this:http://www.digikey.com/product-detail/en/0003061023/WM1230-ND/61242Take some measurements and compare them to the datasheet.

author: clickykbd
author_rank: Newbie
timestamp: April 13, 2016, 04:50:55 pm
content: Quote from: Leuams on February 22, 2016, 05:05:37 amJust wanted to pop back in and say THANKS! That was indeed the right type. After picking up an appropriately rated PS and a little cursing while I crimped some tiny molex pins without proper tools, I now have a working 12x24 HD-SDI router.A smaller crimper is on my wishlist now.Ryan
Find Replacement Component/Component Identification for FLIR T4xx/B4xx Camera - Page 1
Forum section: electronics / repair

author: Chanc3
author_rank: Frequent Contributor
timestamp: April 12, 2016, 02:50:20 pm
content: Hello everyoneI've stripped down a B4xx series camera today as the operator was complaining that the down movement on the joystick was not working. Upon further investigation, it does work correctly if you apply a little bit of pressure and lightly tap down. I took apart the camera to identify the component as I believe one of the internal contacts is failing - funnily enough, this is the 3rd or 4th T4xx/B4xx I have seen with a broken joystick. I'm not an electronics expert, so don't know the correct terminology to use when looking for parts, so I'm hoping someone here can help identify the joystick I need to replace - please see the photographs below:

author: Chanc3
author_rank: Frequent Contributor
timestamp: April 13, 2016, 10:28:36 am
content: Few hours later, it turns out I should have been looking for a 5-way navigation switch!eBay link here for anyone interested:http://www.ebay.co.uk/itm/361471159344Part number is: SKQUDBE010Alps Navigation Switch , 5Way , SMD
Vestel power board advice. - Page 1
Forum section: electronics / repair

author: Mechanical Menace
author_rank: Super Contributor
timestamp: April 12, 2016, 11:51:14 am
content: I've just been given a TV that isn't turning on and as suspected most of the bigger electrolytics on the power board, a Vestel 17PW26-3, are bulging and I'm guessing more than that are also buggered. I've just been pricing up replacements and a refurbished power board is cheaper. Sorry for what is probably a stupid question but does anyone know if all 17PW26-3s are actually identical or if I need to make sure it's actually for my model of TV before ordering?Thanks

author: SeanB
author_rank: Super Contributor
timestamp: April 12, 2016, 06:29:03 pm
content: Vestel made the same board for many models, the new one might be identical, or there might be a few components either added or removed from your board to meet a particular brans price point. At least a new board will give you a power supply with new parts in most cases, just check before putting in that the 2 are identical, but they should interchange.Just tossed a 17in TV out yesterday, same issue of dry capacitors, and I was not going to sit there and change out the 30 or so failed ones and the failed high value resistors ( dim picture) so instead went online price comparing and bought a 17in No Name ( really, that is the brand name, but it is a truly no name set, generic grown box, generic unbranded remote, instruction booklet absolutely no manufacturer info aside from "for service refer to the store you bought this product from" in there) LED flat screen to replace this monitor. Was $61, not even worth the time to fix the old one and have it fail again.
Racal 1992 - Page 1
Forum section: electronics / repair

author: inoxidabile
author_rank: Newbie
timestamp: April 11, 2016, 08:57:39 pm
content: Hi everybody!After some search for the better bargain, I bought a Racal 1992 having options 04A / OXCO and GPIB.I have had to repair just a couple of things but, at the time being, it seems ok .Anyway, there is something I don't understand: looking at instruction manual found on the Web, the AUTO TRIG selections shouldn't have any effects on C channels but only on A or B related inputs.But when I measure a signal on input C, if I select AUTO TRIG as on then the Gate led turns on in a slowly rate and also the indications on display change less frequently... it's like to add a sort of little integration.Moreover, it seems that the Gate led turns on at a slow but fixed frequency, regardless of the resolution setup.Of course, without the AUTO TRIG selection on, the Gate led lamps at a different frequency related to the resolution setup.The software release shown at turn on is 8572 04.04OK, it's not a problem on itself , the reading seems fine but it's different than expected behaviour and I don't know what is the meaning of change I see.Thanks in advance for any explanation about !

author: Andy Watson
author_rank: Super Contributor
timestamp: April 11, 2016, 09:42:13 pm
content: Mine does that too - it's normal.The mechanism for finding the "auto" trigger level is to raise the level until the trigger stops, then lower the level until until it stops - i.e. it tracks the maximum and minimum signal levels. I assume the auto level is then set mid-way between the upper and lower level, and then the frequency is measured. So for every measurement displayed, the processor makes three attempts - three gates - so it slows down. You can monitor the trigger levels on the rear panel - there to two DAC outputs for each channel. Internally, the input frequency is measured by reciprocal counting, i.e. the input frequency is used to gate the reference clock. The auto trig level tracking will therefore cause the gate to operate.I assume the reason that it still tracks the trigger level when using the C channel is that there is an option of measuring the ratio of C/B.

author: inoxidabile
author_rank: Newbie
timestamp: April 12, 2016, 06:12:55 am
content: Hi Andy, many thanks for Your kind reply and report, I posted here because I fear it was something wrong and to repair...Thanks for explanation, it confirms (more or less) my hypotesis but something still doesn't sound clear for me.Looking at schematics I can't see a complete confirmation because the DAC are not present in C channel but I agree with You, it should be a sort of "weighted measure" enabled after the trigger level fixed and then I see its effect in terms of slow gate.Moreover sometimes the trig leds for A and/or B lit and looking in various threads I found someone saying that there could be some little stray coupling or noise at open input.Anyway, coming back to the topic, the main point has been solved: it's a normal behaviour then it's a lack of explanations in manuals
Sony Mega Watchman repair - Page 1
Forum section: electronics / repair

author: mathsquid
author_rank: Frequent Contributor
timestamp: April 11, 2016, 08:49:41 pm
content: Over the weekend I picked up a Sony Mega Watchman at an estate sale for $5. There's no analog TV in the US, but the radio in the unit is still useful, and it was the kind of thing that I'd have loved to have in 1990 or so.It worked except that the tuning knob didn't do anything. It had one of the old string-type mechanisms connecting the dial, variable cap, and knob. A spring kept tension on the string, but the tab that the spring attached to had broken. I replaced it with a screw and it's working now, but the tuning is still loose. If I turn it slowly it will move, but it's not quite right. It was a real pain getting everything back together--a lot like threading a sewing maching, but worse. I never change the station, so I'm not going to open it up again, but I'm wondering if anyone else has experience or pointers on working with these sorts of things.

author: SeanB
author_rank: Super Contributor
timestamp: April 11, 2016, 09:01:18 pm
content: Next time simply take the spring and cut off 3 turns and bend down a single turn to slip over the screw, so that the tension is right. If you do that it will increase the tension back to the right level. I have also taken the spring and unwound that last coil the tab was on to form a hook, and slipped it through the hole instead, so the whole wide section holds it. A drop of nail varnish to lock it there and it will be fine.

author: med6753
author_rank: Super Contributor
timestamp: April 12, 2016, 03:39:08 am
content: Well hello there! Nice to "snow" ya!I picked it up about a year ago. Girl Friend's 95 year old Mother was going into a nursing home and it was in her apartment.It powered up but you couldn't vary either the volume or tone controls. Turns out both shafts had broken plastic right where they go into the pots. Fixed it up and it works fine....on AM and FM of course. I did once connect a VCR to the antenna and got a decent picture.
portable oven earth leakage trip - Page 1
Forum section: electronics / repair

author: phaseform
author_rank: Regular Contributor
timestamp: April 10, 2016, 08:32:59 am
content: I've gotten a hold of a plug in oven which after working fine for a few days has tripped the RCD device. Now the RCD won't even switch back on. I'm not exactly sure about earth leakage principals, the device is showing a measurable resistance between one of the mains pins and the ground. I have disassembled the device and it seems both the top and bottom heating elements each show a measurable resistance to the earth pin. I'm assuming the oven is junk now?

author: Totalsolutions
author_rank: Contributor
timestamp: April 10, 2016, 09:22:52 am
content: I would say so. Howabout replacing the heating elements ?Sent from my GT-N7100 using Tapatalk

author: phaseform
author_rank: Regular Contributor
timestamp: April 10, 2016, 09:24:33 am
content: Ehh I can probably buy one off Gumtree for $30 or find a better solution.On another note I've evidently been in this waiting room over an hour

author: SeanB
author_rank: Super Contributor
timestamp: April 10, 2016, 09:43:32 am
content: You can disconnect both ends of the elements, which will then tell you which one has the leakage. You can buy a replacement element if the oven is expensive, but for a cheap one ( cheapest I have seen retail is $15 this week, though it is barely big enough to get a dinner plate inside it) just scrap it.If you find the faulty element you can get the moisture out of it by heating up with a small gas torch for a few minutes, getting it to over 200C for a few minutes will drive the adsorbed moisture out.
Putting a 7 segment LCD back in place - Page 1
Forum section: electronics / repair

author: Martini
author_rank: Regular Contributor
timestamp: April 10, 2016, 03:43:15 pm
content: Hey !My $10 "precision" scale gave up the other day. Its only problem is with the LCD screen. Some traces looked broken at their (metaphorical) hinge, so I thought I could unglue the ribbon and move it one millimeter. But the black traces were full of glue and didn't make contact. So I cleaned them, now the ribbon doesn't stickAny idea about connecting the screen back to the PCB?(Knowing I don't have conducting glue)

author: SeanB
author_rank: Super Contributor
timestamp: April 10, 2016, 03:58:31 pm
content: Normally done with a hot bar sealer, but doable if you have a temperature controlled iron and set it around 150C to melt the plastic back to the clean board.

author: amyk
author_rank: Super Contributor
timestamp: April 10, 2016, 04:12:16 pm
content: Anisotropic conductive tape could be an easier solution if you can find some.

author: wraper
author_rank: Unknown
timestamp: April 10, 2016, 04:23:39 pm
content: Z-axis conductive tape would do the jobhttp://www.ebay.com/itm/262379455349. However it is expensive (that price is for a tiny piece) and won't help anyway. By tearing off that ribbon cable, you destroyed it beyond repair. Conductive traces from the cable remained on the PCB, what left on the cable is insulated from the both side and therefore is not accessible. And you won't be able to remove the insulating layer without damaging the traces anyway. So just buy another scales.

author: Martini
author_rank: Regular Contributor
timestamp: April 10, 2016, 05:07:29 pm
content: Wow, those tapes look cool, I didn't know such solution existed.Quote from: SeanB on April 10, 2016, 03:58:31 pmThat didn't work at 150°C, I'll try to up the temp a bit tomorrow when I have more light to work.Quote from: wraper on April 10, 2016, 04:23:39 pmResistance of the black traces is a few hundred ohms when the probes are 5 mm apart. Is that congruent with the insulation you're talking about?

author: wraper
author_rank: Unknown
timestamp: April 10, 2016, 05:19:57 pm
content: Quote from: Martini on April 10, 2016, 05:07:29 pmDunno, maybe some super cheap uninsulated type. Few hundred ohms is about right resistance for carbon traces.

author: amyk
author_rank: Super Contributor
timestamp: April 11, 2016, 09:33:30 am
content: Physically hold it in place (firmly) if you want to test whether it will work. If there's any conductivity it should, LCDs don't require much current at all to operate.

author: Martini
author_rank: Regular Contributor
timestamp: April 11, 2016, 09:45:47 am
content: Quote from: amyk on April 11, 2016, 09:33:30 amOh, it does. But it's really tricky to align and put pressure on all the contacts at the same time.
Ram chip scope measure - Page 1
Forum section: electronics / repair

author: Daxxin
author_rank: Regular Contributor
timestamp: April 10, 2016, 02:38:21 pm
content: getting troubles with very very old scope videocard (37 white thin vertical lines) checkingthe ram chip DIP18 M5M4416p something look weird to me but maybe its normal someone can explainwhy i get this tooth saw 400mv between one pulse and next? it is normal?not all the pin like this some data have pulses very clear , example from pin 3 i get this.

author: SeanB
author_rank: Super Contributor
timestamp: April 10, 2016, 04:10:25 pm
content: Most likely a clock appearing as noise on the data line, caused by a combination of scope ground lead inductance and the internal bond wire length in the chip and processor. Try measuring again minimising ground lead distance and it should vanish, or drop in amplitude. As it is a lot less than a valid logic low or high it should not be a worry. Vertical white lines though do tend to say there is either a ram address fault or a faulty chip. Check for dry joints on the chips and if they are in sockets remove and reinstall them to clean the pins. You could also have a socket with a broken pin, which is hard to trace as they break inside the plastic housing.
Tesla Oscilloscope BM566 Repair - Page 1
Forum section: electronics / repair

author: darkness_electro
author_rank: Contributor
timestamp: March 26, 2016, 05:59:55 pm
content: I posted a long time ago about my trouble with the scope and in the last few days i tried to give it another go.i attached the schematic and the board layouts, and i have some questions.http://www.filehost.ro/3172105588/BM566a_pdf/1. on the last page, down left, the push pull output for the intensity control doesn't work (near U212) there is no were in the manual anything about how much it should be, but i traced a little and it seems to be the intensity. The 2n3495 has been replaced with a mpsa92, and the npn transistor gets burnt whatever i do. So i left it out, and the illumination is at it's peak. Can you suggest a transistor that would work? MPSA42 doesn't unfortunately, and R175, R176 and R178 get burnt.2. The scope is seriously out of calibration. On most scales (0.1V/div and lower) a 4v signal fills about 3 divisions, and on a 1v/div it's like 1-2mm tall. At most. Can this be a deflection problem, aka it doesn't have enough voltage to show it all? Also it has so much ripple on the deflection it looks line a sine wave superimposed over the square one. It cannot be brought into calibration by any knob. It's like i need a 10X amplifier.3. When the scope displays the image it looks like a part of it is squished to the left, where the trace starts. This should be a deflection issue, right? But even if i move it left or right it's the same. A part of the image is squished there.It has a lot of other problems but those are bad.I have checked the power supply and it's spot on. The electrolitycs are older than Dave but they work a treat. The voltages going in all the boards are ok. (+-2%). I don't have the courage to probe the HV stuff, but it seems ok. I have an image.If i was not too suggestive with my description of the issues please ask for more info.

author: orbanp
author_rank: Regular Contributor
timestamp: April 10, 2016, 12:23:51 pm
content: Hi Darkness_electro,The site with the schematics needs you to log in.Can you share the schematics in some other ways?My guess is this is the reason that you are not getting any replies.Peter