hybridfree/eevblog-posts huggingface dataset:
Creepage Distances  - Page 1
Forum section: electronics / general

author: David
author_rank: Frequent Contributor
timestamp: November 22, 2012, 07:43:45 pm
content: Hi all,I have a quick query regarding creepage distances and how they are defined. Standards such as EN60950 specify the creepage and clearance distances for, amongst other things, "current carrying parts of different polarity". Now, obviously the Live and Neutral lines in a circuit will be constantly alternating polarity. Does this therefore mean that the same creepage distance is required between say the neutral and some other circuitry and the live line and other circuitry? Also is "working voltage" defined as the potential difference between two conductors?

author: Kremmen
author_rank: Super Contributor
timestamp: November 22, 2012, 09:36:26 pm
content: IEC 60950 talks about curent carrying parts and conductors in many places, but the creepage distances are mostly laid out on Annexes F and G. The distances apply only to circuits with the defined overvoltage classes in table G.1. The required clearances are listed in table G.2. Earlier in the text you will find tables 2L and 2N based on the working voltage of the particiular circuit. For the definition of working voltage see 2.10.2.
Power supply with visible current set without having to short. - Page 1
Forum section: electronics / general

author: Chupa
author_rank: Contributor
timestamp: November 22, 2012, 01:36:28 pm
content: What are some good bench power supplies that allow you to set current limit without having to short the leads? 0-30V 2A is fine. Switching or linear.

author: Matje
author_rank: Regular Contributor
timestamp: November 22, 2012, 11:37:21 pm
content: Quote from: Chupa on November 22, 2012, 01:36:28 pmJust a warning: both BASETech BT-305 and RG-303Pro do have this feature (these are linear supplies, theoretically up to 5A, yeah, if only...).Both are based off the same design. Thus both share a serious misfeature: when switching off the output(s) via the extra button for doing so the output(s) will produce a powerful spike of up to 3 volts above the voltage set. Powerful means it occurs even when pulling a lot of current. Powering some chip needing 3.3 volts from one of these will likely be fatal for the poor chip.So don't get these. They are very likely sold under a lot of different "brand" names too.

author: JuKu
author_rank: Frequent Contributor
timestamp: November 23, 2012, 11:16:38 am
content: My Atten PPS3203T-3S can. I don't know if it is "good", but works for me. I bought it because it was the only one I could find at reasonable price that can simultaneously display the current consumed be three outputs.

author: Chupa
author_rank: Contributor
timestamp: November 23, 2012, 02:45:59 pm
content: Quote from: JuKu on November 23, 2012, 11:16:38 amOh! that one looks real nice
[Melbourne, Australia] Rosebud Radio Festival 25th November - Page 1
Forum section: electronics / general

author: johnboxall
author_rank: Unknown
timestamp: November 22, 2012, 04:38:28 am
content: If you're around Melbourne on the weekend and interested in amateur radio, or looking for some used radio and other electronics gear - head down to Rosebud on Sunday 25th. More information here -http://www.rosebudradiofest.com/
looking for an enclosure - anyone help please ? - Page 1
Forum section: electronics / general

author: mickpah
author_rank: Regular Contributor
timestamp: November 20, 2012, 07:48:53 pm
content: HiI'm in the final stages of a project and thought I had the perfect case, but it's turned out to be just bit small.The one I have is 56x110x160 mmhttp://www.seeedstudio.com/depot/practical-plastic-enclosure-56x110x160-mm-p-1002.html?cPath=178_184I am mounting a 16x2 Oled behind the window so this type is important.Anyone know where I can get a larger version ?thanks, I've worn out my google fingers trying.

author: DeanA
author_rank: Regular Contributor
timestamp: November 21, 2012, 08:14:38 am
content: Hi,Have you had a look at something by OKWhttp://www.okwenclosures.com/products/okw/hand-held.htm.Or Teknethttp://www.tekoenclosures.com/enclosures/teknet-pulpit.htmI know what it can be like trying to find the perfect enclosure, a real PITA trying to find the right one after the PCB has been done, I'll never do that again.Regards,Dean.

author: EEVblog
author_rank: Unknown
timestamp: November 21, 2012, 10:50:43 am
content: Don't forget the Wiki list:http://eevblog.com/wiki/index.php?title=Enclosure_ManufacturersDave.

author: GeoffS
author_rank: Unknown
timestamp: November 21, 2012, 11:05:32 am
content: There's a wiki?

author: notsob
author_rank: Frequent Contributor
timestamp: November 21, 2012, 11:48:20 am
content: and there are these guyshttp://www.bahar.asia/en/

author: mickpah
author_rank: Regular Contributor
timestamp: November 21, 2012, 12:46:13 pm
content: Thanks!!!! spent hours looking ( used your wiki too Dave) no one seems to have a parametric search for enclosures.This looks to be the go forhttp://www.bahar.asia/en/Products4.asp?nid=107
Transplanting AC Option -09 from Fluke 8840 to 8842? - Page 1
Forum section: electronics / general

author: reagle
author_rank: Unknown
timestamp: October 04, 2012, 11:05:45 pm
content: I've attempted the above transplant of the AC option module, only to find that my instrument is still giving me error 30 when trying to do any AC measurements. Is there any magic required in telling my meter that it now has the new option installed? the installation seems rather simple- one ribbon cable and one power lead.

author: reagle
author_rank: Unknown
timestamp: October 05, 2012, 02:36:32 am
content: I am being told the pinout actually differs slightly between option 9 module in 8840 and 8842. Upon closer examination, it appears that pins 1 and 8 are swapped. They are AC_SENSE and CS4. Now, why would they do such a silly thing?

author: Wartex
author_rank: Frequent Contributor
timestamp: November 21, 2012, 04:30:43 am
content: did you get this working?
What tricks they do to hire a Technician! - Page 1
Forum section: electronics / general

author: T4P
author_rank: Super Contributor
timestamp: November 20, 2012, 06:17:21 am
content: Share all your tricks! Or what have you been tricked with before?I have one :So they hand all the candidates a stack of paper with 50 random questions and they have complete the stack within 30mins1) They are to read all the instructions and question thoroughly2) Name on the top right and IC number on the top leftMany of them scratched their head for 2 days being able to complete but didn't pass the test why?Someone finally passed the test, why?Question 50 said Do not write anything anywhere on the paper and only 1 person finally did read the instructions and carried it outThe reason why they some of them do it is because as technician instructions are to be wholly read and carried out and it's a good test

author: Psi
author_rank: Super Contributor
timestamp: November 20, 2012, 06:45:28 am
content: Quote from: T4P on November 20, 2012, 06:17:21 amIC number, hm..*Psi writes NE555 top left of paperEdit: well, i guess i failed, i made that comment before I finished reading your post

author: TriodeTiger
author_rank: Regular Contributor
timestamp: November 20, 2012, 07:14:33 am
content: Quote from: Psi on November 20, 2012, 06:45:28 amHow bouts..Signetics 25120Fitting as the paper will not be read after you on write it :-)

author: peter.mitchell
author_rank: Super Contributor
timestamp: November 20, 2012, 07:33:26 am
content: that seems like /dev/null

author: Anks
author_rank: Frequent Contributor
timestamp: November 20, 2012, 04:01:50 pm
content: Quote from: T4P on November 20, 2012, 06:17:21 amMy dad told me this story about when he worked for British Areospace.He said the last thing on his paper said only complete question 7 and 29.

author: TriodeTiger
author_rank: Regular Contributor
timestamp: November 21, 2012, 12:47:35 am
content: Quote from: Anks on November 20, 2012, 04:01:50 pmMy mom told me way back on an exam she got a similar "Read the exam thoroughly [......] Turn your paper over with nothing written. You have completed the exam."Guess it's popular.
What "Earth-Shaking" Discovery Has Curiosity Made on Mars? - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 20, 2012, 03:19:26 pm
content: "NASA scientists have some exciting new results from one of the rover's instruments. On the one hand, they'd like to tell everybody what they found, but on the other, they have to wait because they want to make sure their results are not just some fluke or error in their instrument. The exciting results are coming from an instrument in the rover called SAM. 'We're getting data from SAM as we sit here and speak, and the data looks really interesting,' says John Grotzinger. He's the principal investigator for the rover mission. SAM (Sample Analysis at Mars) is a suite of instruments onboard NASA's Mars Science Laboratory rover, Curiosity. Grotzinger says they recently put a soil sample in SAM, and the analysis shows something Earth-shaking. 'This data is gonna be one for the history books. It's looking really good,' he says."http://www.npr.org/2012/11/20/165513016/big-news-from-mars-rover-scientists-mum-for-now

author: JuKu
author_rank: Frequent Contributor
timestamp: November 20, 2012, 03:37:48 pm
content: Life?"SAM – Sample Analysis at Mars (SAM) is a suite of three instruments: a gas chromatograph, a quadrupole mass spectrometer, and a tunable laser spectrometer. Together they search for and measure the abundances of carbon, oxygen, hydrogen, and nitrogen - elements that are associated with life as we know it. "It is already known that Mars atmosphere contains methane, and the concentration increases on summer in areas where temperature is above 0C. There are other possible explanations, but bacteria-like activity is by far the most probable. So, it would be not that big surprise, but huge news anyway.
Changing Careers - Page 1
Forum section: electronics / general

author: plavelle2k12
author_rank: Newbie
timestamp: November 19, 2012, 08:27:44 pm
content: Hi,I live in the UK and currently work in I.T, but I am considering a career in Electronics Engineering instead. I have long been interested in Electronics and caught the Arduino bug a couple of years ago.At the risk of rambling on too long my question is: Is 29 too late to re-train for an EE career?Has anyone on this forum come into the EE field from another profession after they graduated? If so, I'd be interested to hear your experiences of training and hunting for that all-important first EE job.

author: nanofrog
author_rank: Super Contributor
timestamp: November 19, 2012, 08:46:58 pm
content: Quote from: plavelle2k12 on November 19, 2012, 08:27:44 pmI don't believe it's too late at all.Quote from: plavelle2k12 on November 19, 2012, 08:27:44 pmHad my first engineering job prior to finishing school in the Components Eng. Dept. at Lockheed, which ended in a lay-off due to Congressional budget cuts (contracts cancelled). Finished my first degree in Materials Eng., but hated the job I got (QC for a co making food containers). Went back to school for MS Computer Eng., and got a job through someone I met walking around on campus (he was signing his company up for a job fair). Figure I was beyond lucky that day (right place, right time).

author: ptricks
author_rank: Frequent Contributor
timestamp: November 19, 2012, 10:05:21 pm
content: Never too old.One of the best engineers I ever met was a 67 year old grandmother who had started her electronics career at age 60 at the urging of her grandchildren. She was formerly a school teacher who taught 9 year olds.
What Solder To Buy - Recommendations - Horror Stories - Page 1
Forum section: electronics / general

author: SgtRock
author_rank: Unknown
timestamp: November 18, 2012, 02:54:15 pm
content: Greetings EEVBees:--I am going to order some 63/37 solder, in a number of diameters. I do a lot of general repair work of both through hole and surface mount. I try to repair anything my friends need help with; PCs, Laptops, TVs, Meters and instruments, and any items from the dumpster that can be repaired and flogged on eBay. I would welcome any recommendations, and/or horror stories. Is the stuff on eBay from Hong Kong OK, or should I order from a domestic source."Happy for you to desoldering, please."Wun Hung Lo 1948 -Best RegardsClear Ether

author: mariush
author_rank: Super Contributor
timestamp: November 18, 2012, 03:08:11 pm
content: I'd recommend this:http://www.digikey.com/product-detail/en/397982/82-131-ND/2498929Flux Type No-CleanComposition Sn63Pb37 (63/37)Wire Gauge 28Diameter 0.015" (0.39mm)Core Size 3%Form Spool, 227g (1/2 lb)It's no clean, good amount of flux making your life easier. Diameter may be a bit too thin for your liking, I personally use 0.56mm diameter and I feel it's just fine for soldering through hole stuff.If you want a bit more diameter, they only have 0.56mm of no clean variety in bigger spool:http://www.digikey.com/product-detail/en/386851/82-129-ND/2498927In smaller quantity, this may be a good 0.56mm diameter alternative. It's water soluble, instead of no-clean so I don't have experience with this one, maybe others can chip in and confirm it's good or not:http://www.digikey.com/product-detail/en/386820/82-134-ND/2498932

author: Prizmatic
author_rank: Regular Contributor
timestamp: November 18, 2012, 04:34:30 pm
content: Ersin M7 for through-hole, great stuff.
Strange buffer with Rail-To-Rail opamp - Page 1
Forum section: electronics / general

author: Leo Bodnar
author_rank: Frequent Contributor
timestamp: November 18, 2012, 03:23:44 pm
content: I am a bit puzzled by this Vdd/Vref buffer suggestion from AD.It features in quite a few of their datasheets.It this some magic circuit or just a carry-on copy and paste glitch?Leo
Psi'O'9 Style Heads Up - (Physics) We are Doomed! - Page 1
Forum section: electronics / general

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 18, 2012, 02:50:14 am
content: we have the model but we cant prove it... i said its flawed! find another model!or buy Agilent3000X series, Atlas is just another Rigol DS1052E (cannot find glitches).where is He when we need Him?

author: GeoffS
author_rank: Unknown
timestamp: November 18, 2012, 03:22:50 am
content: Perhaps I'm missing the point here. What does this have to do with oscilloscopes ?

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 18, 2012, 03:33:02 am
content: sorry didnt clarify. i'm not Agilent affiliate. i mean buy (or build) a "better Atlas".

author: free_electron
author_rank: Super Contributor
timestamp: November 18, 2012, 01:10:12 pm
content: Quote from: Mechatrommer on November 18, 2012, 02:50:14 amIt's a She , and She's taking a beauty sleep.
Engineering comedy - UK style - Page 1
Forum section: electronics / general

author: Pat Pending
author_rank: Regular Contributor
timestamp: November 18, 2012, 06:37:42 am
content: Looks as if engineers can be comedy script writers.Skip to 6:20 - 7:20

author: poptones
author_rank: Frequent Contributor
timestamp: November 18, 2012, 07:06:15 am
content: What a coincidence. This is one of my favorite UK comedians.Extreme Speed Record Player
SLA Charger - Page 1
Forum section: electronics / general

author: LAZLOT
author_rank: Contributor
timestamp: November 18, 2012, 04:32:57 am
content: Is it practical to modify a 12volt car bty chgr to 6v simply by mod'ing the o/p reg? I mainly ask because I'm not sure what effect this will have on the current sense part of the circuit (chgr unsighted so far, so no details avail.). I have a circuit dia. for a dedicated 6v SLA charger, so any replies need not go down that path, Ta. More curious about the possibility of the o/p mod, and whether a car bty charger is compatible with SLA bty's, and what mod'ing the o/p level does to the current sense.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 18, 2012, 04:46:54 am
content: It would not be worth the effort.

author: LAZLOT
author_rank: Contributor
timestamp: November 18, 2012, 05:06:09 am
content: Thank's, I thought so... I'll be building the circuit I found on the web instead...http://www.sentex.ca/~mec1995/circ/bcgla2.htm-a handy site- click on the CIRCUITS PAGE link at the bottom of the page for more...

author: rr100
author_rank: Frequent Contributor
timestamp: November 18, 2012, 05:38:20 am
content: The floating voltage regulation looks terrible, you rely on the input voltage to be not only regulated but regulated to a known/stable value and on the voltage drop on the transistor (which varies significantly with the current).

author: SeanB
author_rank: Super Contributor
timestamp: November 18, 2012, 06:06:10 am
content: It really depends on the charger. Cheap ones have no regulatiion, and only provide a limited current, relying on you to disconnect them after the battery is charged.Chargers for SLA 12V alarm style batteries are better, but typically use a 7812 regulator to do the charging. These can be modified by using a 7805, though you will have to change the transformer to an 8V unit, or add a large wirewound resistor to dissipate the 20W or so of heat otherwise, which the 7805 on the barely usable heatsink normally provided will never be able to do. This then will be a reasonable 6V charger, you set the ouptput voltage to the float voltage on the cell, typically around 6.9V.
TEK TDS 320 ch2 trace is off after 2 minuts of POWER ON - Page 1
Forum section: electronics / general

author: jalves
author_rank: Contributor
timestamp: November 11, 2012, 03:49:56 pm
content: Hi,I bought a used Tektronix TDS320 and it worked well from the box.I was happily learning how to set it up to "look" over a video PAL signal (I am trying to implement a video telemetry for my hobby) using dual trace when suddenly the channel 2 trace oscillate and goes up in the display and disappear, the triggering for this channel becomes inoperative and the channel useless.Now, after a power off and some hours of rest, when I turn on the Tek the channel 2 is operative as usual, but only for about 2 minutes, after that it goes away.Channel 1 works (so far) with out problems.Running some diagnostics in the scope, it yields 6 Acq errors:diagAcq_fisoShortPipediagAcq_fisoCelldiagAcq_peakDetectAcqdiagAcq_holdoffdiagAcq_ch2TriggerdiagAcq_ch2SigPathI open the scope only to find a very clean boards and little dust inside, look for bad caps but couldn't see any that look like in the need of replacement.I hope there are some Tek TDS scope users that can give me an hand, because I am clueless about what to next.

author: tom66
author_rank: Super Contributor
timestamp: November 11, 2012, 03:57:13 pm
content: My bet would be a cold joint on one of the analog supplies for that channel. (If it's a very low noise unit, it'll use one supply for each channel.) I had a HP 54501A which would do a similar thing, except all the traces would go off screen and the unit would reset/power cycle after some time. The -12V was dropping out due to a bad solder joint on the power supply connector.

author: jalves
author_rank: Contributor
timestamp: November 13, 2012, 09:43:37 am
content: in this case CH1 works flawlessly.CH2 work for some time and then the trace goes up and disappear.It seems the logic unit of the scope is receiving a erroneous level signal from CH2 input stage.The question is how can I debug this input area of the scope, this is a "hybrid" ceramic board TEK US 165 2500http://www.qservice.tv/N_PICS/PICS_TEK_SPARES/ALL_8/EX_LARGE/DSC02534.JPG

author: jalves
author_rank: Contributor
timestamp: November 18, 2012, 12:09:41 am
content: The problem is solved!You can read here how:http://www.edaboard.com/thread271343-2.htmlThanks.
Fluke 87 V Resistance Problem - Page 1
Forum section: electronics / general

author: SgtRock
author_rank: Unknown
timestamp: November 17, 2012, 04:09:21 pm
content: Greetings EEVBees:--This Fluke 87 shows resistance 187K where it should show infinity, see picture below. It is for sale on eBay. Is this likely a burned out resistor network or what? I was thinking of bidding on this one for parts. Any advice would be appreciated. You of course are also welcome to bid."Happy for you to desoldering, please."Wun Hung Lo 1948 -Best RegardsClear Ether
Building DMM leads - Page 1
Forum section: electronics / general

author: WhiteFireDragon
author_rank: Regular Contributor
timestamp: November 17, 2012, 07:57:46 am
content: I'd like to build leads for my multimeter. Yeah, I can just buy them, but I like building stuff and I also want some customized tips. Here are the parts I came up with so far:Alligator clips:toothless clip(for LED wire),standard clip(for general purposes)banana plugs:shrouded(for DMM),non-shrouded(for alligator clip side)probes:test probes(plugs into banana plugs)wires: ??I'm assuming all banana plugs are 4mm sizes? Please check if the banana plugs I choose are correct, because I'm not sure if I can solder a wire onto those. And I need help on which wire/cable to get. I would like something really flexible, so I'm assuming silicone insulated wires? Also, copper clips are better at conduction, but will corrode faster than steel, correct? Thanks in advance

author: T4P
author_rank: Super Contributor
timestamp: November 17, 2012, 08:05:56 am
content: Silicone AWG16/18 wiresAnd look for another type of non-shrouded jacks, the pomona ones are terrible quality that comes from china (Don't assume!)But in my knowledge "wireless" test leads usually accept shrouded ones

author: WhiteFireDragon
author_rank: Regular Contributor
timestamp: November 17, 2012, 09:40:24 am
content: Ok I'm going to go with these16awg siliconewires. I'm hoping total diameter is less than 4.5mm because the shrouded banana plug can't accept wires any bigger according to thedata sheet. I'm also going to go withTHESE4mm banana plugs because they look less cheap, and require soldering of the wire for attachment. What are the standard wire sizes for multimeter leads, like the ones Fluke uses? I'm looking for the biggest possible wire that can fit to minimize the resistance.

author: T4P
author_rank: Super Contributor
timestamp: November 17, 2012, 09:45:47 am
content: No idea but the probes i have are mostly 95cm-120cm or 1.2m

author: WhiteFireDragon
author_rank: Regular Contributor
timestamp: November 17, 2012, 10:07:30 am
content: Ah I meant wire thickness, not length. The leads from my amprobe has wires that are 3.5mm thick, so I'm hoping 16awg wires won't be more than 4.5mm thick, otherwise it probably won't work with a lot of the parts I'm ordering.

author: notsob
author_rank: Frequent Contributor
timestamp: November 17, 2012, 10:37:47 am
content: Read this thread for source of silicon wire, bananas and general techniquehttps://www.eevblog.com/forum/product-reviews-photos-and-discussion/high-quality-banana-plugs-alligator-clips-ect/msg146653/#msg146653
From killing viruses to killing..John McAfee Wanted for Murder - Page 1
Forum section: electronics / general

author: ErikTheNorwegian
author_rank: Frequent Contributor
timestamp: November 12, 2012, 09:04:46 pm
content: ref

author: saturation
author_rank: Super Contributor
timestamp: November 12, 2012, 10:27:13 pm
content: http://en.wikipedia.org/wiki/John_McAfeeMore to the story.

author: Wartex
author_rank: Frequent Contributor
timestamp: November 12, 2012, 10:50:21 pm
content: Quote from: saturation on November 12, 2012, 10:27:13 pmHe was cleared, but he is still a pedo for dating a 17 year old (which he has dated for a while now).

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 12, 2012, 11:32:27 pm
content: so is wanted ?

author: aluck
author_rank: Regular Contributor
timestamp: November 13, 2012, 10:16:26 am
content: Quote from: Wartex on November 12, 2012, 10:50:21 pm17 years old sounds OK for me. Legal age here is 16 years.

author: peter.mitchell
author_rank: Super Contributor
timestamp: November 13, 2012, 10:45:52 am
content: don't know if this is of any interest to anyonehttp://en.wikipedia.org/wiki/David_Petraeus#Extramarital_affair_and_resignation

author: poptones
author_rank: Frequent Contributor
timestamp: November 13, 2012, 04:17:29 pm
content: Someone needs to look up pedophile.Pedos are not interested in 17 year olds, they're interested in 7 year olds.And no, why do I give a shit that some dude had an affair? It's gossip, nothing more.

author: SeanB
author_rank: Super Contributor
timestamp: November 13, 2012, 04:47:34 pm
content: Marriage age here is 15...................

author: poptones
author_rank: Frequent Contributor
timestamp: November 15, 2012, 06:10:34 pm
content: He looks like that homeless dude before he got his face ate off.

author: aluck
author_rank: Regular Contributor
timestamp: November 18, 2012, 02:06:43 pm
content: Nice abs for an aging geek. He is kind of cool.
Anybody using vrint pcb service? - Page 1
Forum section: electronics / general

author: Spikee
author_rank: Frequent Contributor
timestamp: November 17, 2012, 12:00:25 am
content: Hello , i was looking for a faster double sided pcb service.I used Seeed(14-30 days) , Itead(14-30 days) and oshpark(18 days) .I looked trough UK , China , US , NL , DE services and the cheapest resonable pcb prototyphe was around 50 euro and a tunraround of 8-10 days.But on a german forum i found a (russian ? ) pcb service who offers 100x160 mm (euro card) , gold finish , e-test , soldermask + silkscreen for 44 euro (promotion) . The best thing is 3DAYSturnaround !The non - promotion prices are around the same.They seem to be a reputable company but i would like to know if anyone has used them before ?http://vrint-pcb.com/show/15-Prototype-PromotionThanks, SpikeeEdit:Just saw they do a free pcb for new customers 1,6 square dm . Guess i'll try that out soon.

author: free_electron
author_rank: Super Contributor
timestamp: November 17, 2012, 12:15:46 am
content: with a company name of vi-rus ... someone didn;t do some thinking.and theyre not russian but bulgarian.their technology is crap though.. 10 mil track and gap. or price goes up.

author: Spikee
author_rank: Frequent Contributor
timestamp: November 17, 2012, 12:20:08 am
content: I sent them an email for some details on the promotion and the pcb.10 mil track and gap is not ideal but is do-able for most situations.I'll have to see how much the extra costs are for 6 mil spacing.Edit:If you look at the site in Bulgarian it seems they asked / got EU Subsidy some photo .. machine .I guess they are upgrading their capabilities .http://bg.vrint-pcb.com/news/show/14
Can someone calibrate my 87 III for reasonable cost? - Page 1
Forum section: electronics / general

author: ElectonicaThomas
author_rank: Newbie
timestamp: November 16, 2012, 04:49:28 am
content: Just bought 87 III from ebay in apparently excellent condition. I am a newbee don't know if I should send out for Cal.... as it is expensive. Are there some simple checks I can do. I have an old fluke 77 my brother gave to me. Can I use this to compare, or should I send it out to one of you guys to check? cheers Tom

author: EEVblog
author_rank: Unknown
timestamp: November 16, 2012, 06:13:09 am
content: Yes, use the two meters to compare.If they are both spot with each other, it is virtually certain that both are ok and within spec.Dave.

author: ElectonicaThomas
author_rank: Newbie
timestamp: November 16, 2012, 06:19:35 am
content: Wow, I got a response from Dave Himself !!! I don't think I will sleep tonight. Thanks Dave I'm printing this email out and framing it! Next party, everybody, beer in hand, will be staring at my framed email. Cheers from Canuckistan PS They all watch your blogs.

author: LEECH666
author_rank: Frequent Contributor
timestamp: November 16, 2012, 02:29:24 pm
content: But this isn't an email? ... Or is it?

author: notsob
author_rank: Frequent Contributor
timestamp: November 16, 2012, 10:21:02 pm
content: IF you choose to do it yourself try a DMMCheck,http://shop.voltagestandard.com/
Agilent U8001A - Page 1
Forum section: electronics / general

author: perfect_disturbance
author_rank: Regular Contributor
timestamp: November 15, 2012, 11:25:34 pm
content: What do people think about the Agilent U8001A as compared to the E3610A?

author: Spikee
author_rank: Frequent Contributor
timestamp: November 16, 2012, 09:48:39 am
content: I bought an Agilent U8001A a few months ago and i'm not disappointed of it.I like the higher output so i can drive some high power leds in series and various other applications.The only annoying thing is that the fan will go in it highers speed when you pull around 3 amps. But if your load is switching on / off the fan goes low , high , low, high rpm .... The set voltage / current is good and also the voltage and current readout is good. ( x.xx V x.xx A ) .It is also a sturdy and it has some weight in it so it feels good. Only the front plate is plastic , the rest is painted alu / iron .
Success Denied - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 15, 2012, 04:45:37 pm
content: The ironically-named Justin Success Brooks was accused of selling thousands of counterfeit Wii, DS and DSi Nintendo games between 2009 and 2011 - pocketing himself up to £600,000 in the process - and that pleaded guilty to all charges. His court case was scheduled for November 9th, in which he has been sentenced to 32 months jail time, but was also told he could expect to serve just half of that.http://www.croydonguardian.co.uk/news/10039578.Fraudster_who_sold_counterfeit_Nintendo_games_jailed/

author: amyk
author_rank: Super Contributor
timestamp: November 16, 2012, 06:55:59 am
content: Quote from: DiligentMinds.com on November 16, 2012, 02:52:59 amThis sounds like a saner decision than the usual... where someone charged for assault would get off with less than for torrenting a few songs...

author: Bored@Work
author_rank: Super Contributor
timestamp: November 16, 2012, 07:09:08 am
content: He should be quick moving to a Caribbean island. If he gets out Nintendo could already wait at the prison gate with a £12 million bill.But I do remember a story of a criminal fleeing to the Caribbean with a lot of money. Word got out to local criminals, and they offered to "protect" him for a share of the money. And another share. And another share ... His money didn't last long.
Can anyone tell what this camera was used for? - Page 1
Forum section: electronics / general

author: firewalker
author_rank: Super Contributor
timestamp: November 15, 2012, 04:50:33 pm
content: I found on the local recycling center this camera. It works. But I can't tell what it was used for. The enclosure is made by heavy (non magnetic metal). I couldn't find anything with a quick internet search.

author: Kremmen
author_rank: Super Contributor
timestamp: November 15, 2012, 05:04:06 pm
content: Possibly a machine vision camera for parst inspection or manipulation of some kind. Hard to say anything more and even that could be totally off.

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 15, 2012, 05:11:31 pm
content: ooo nice teardown and hack project

author: ErikTheNorwegian
author_rank: Frequent Contributor
timestamp: November 15, 2012, 07:51:11 pm
content: Its a CCU, Camera controll unit, for surveillance cameras, this one has a camera attached directly, a typical OEM unit.. probebly from some medical equipment. seen units like this in xray , MR machines..A tip is to check the lens of the camera, to see what distance with it covers.

author: PA0PBZ
author_rank: Super Contributor
timestamp: November 15, 2012, 08:43:25 pm
content: Could be mining stuff looking at the KPI name on it :http://www.kpiind.com/ip-network-camera-video-tablet-system/
What the hell is happening to these ribbon cable connectors ? Bio degradable ? - Page 1
Forum section: electronics / general

author: BravoV
author_rank: Super Contributor
timestamp: November 16, 2012, 08:37:29 am
content: These boards were stored in the anti static bag in dry storage for like maybe 1 or 2 years, and just found out the connector's surface (the black one) are growing some sort of white crystal thingy, and no, its not fungi, cause it feels in my finger like a fine table salt crystal and can be easily wiped clean too. Other adjacent components are just fine and still look like new.Any idea why is this happening ? Bio degradable plastic ? Is it bad ?PS : Attached below other close up shots that are cropped, but still at 1:1 for showing the details, don't worry, managed to save it at reasonable size under 500K each for easy viewing rather than those annoying megabytes picture..

author: Balaur
author_rank: Unknown
timestamp: November 16, 2012, 09:42:40 am
content: Here are some hypotheses:Fire retardant chemicals (or other additives) in the connector plastic that is now seeping out?Less probable - some plasticizer in the packaging materials (the antistatic bags or even the previous packages where the connectors were kept before assembly)?Cheers,Dan

author: Psi
author_rank: Super Contributor
timestamp: November 16, 2012, 10:32:06 am
content: Quote from: Balaur on November 16, 2012, 09:42:40 amThat would be my guess as well. Probably a bad batch which was mixed wrong.

author: RCMR
author_rank: Frequent Contributor
timestamp: November 16, 2012, 09:09:31 pm
content: Since I see you have aq as your country -- I suspect it's ice :-)

author: BravoV
author_rank: Super Contributor
timestamp: November 17, 2012, 06:18:56 pm
content: Quote from: Balaur on November 16, 2012, 09:42:40 amYeah, the 1st hypothese is more likely, cause the those fine grain crystal only grow at that particular black connector's surface while other part still in good condition. Also as those shots show, the copper pins still shiny untarnished at all, proof that the storage condition is pretty good.These nasty crystal flakes have the hardness similar to fine grain table salt, and easily chipped off, definitely will cause problem when fallen into other nearby mechanical component part like adjustment pot, trimmer cap or unsealed dip switch.

author: PA0PBZ
author_rank: Super Contributor
timestamp: November 17, 2012, 08:02:39 pm
content: QuoteSince you can't be sure the process has stopped, just replace the connectors if you want to use the boards.
This one is a visualization of the locations of over 100,000 nearby stars - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 14, 2012, 11:16:25 pm
content: Google has rolled out a new web experiment for Chrome. This one is a visualization of the locations of over 100,000 nearby stars. It pulls data from astrometric databases and catalogued to show accurate relative locations of the stars. You can zoom and pan around the cluster, zoom all the way in to the solar system, or zoom all the way out to see how even this huge number of stars is dwarfed by the rest of the Milky Way. It also has data on a number individual stars in our stellar neighborhood. This web app works best in Chrome (much like their previous one, Jam With Chrome), but I was able to try it in Firefox as well.http://workshop.chromeexperiments.com/stars/

author: EEVblog
author_rank: Unknown
timestamp: November 15, 2012, 01:40:34 am
content: It staggers me how they can map that many to begin with and get all the data.Dave.

author: SeanB
author_rank: Super Contributor
timestamp: November 15, 2012, 04:36:58 am
content: 10000 amateur astronomers took a century to gather the data..........
Everspin Non-Volatile MRAM 500 Times Faster Than NAND - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 14, 2012, 10:54:26 pm
content: Magnetoresistive Random Access Memory'The hypothetical holy grail — a non-volatile, low-latency, low-cost product that could scale from hard drives to conventional RAM.NAND flash has become the high-speed, non-volatile darling of the storage industry, but if you follow the evolution of the standard, you'll know that NAND is far from perfect. The total number of read/write cycles and data duration if the drive isn't kept powered are both significant problems as process shrinks continue scaling downward'http://www.extremetech.com/computing/140318-everspin-launches-new-non-volatile-magnetic-ram-thats-500-times-faster-than-nand-flash

author: FenderBender
author_rank: Super Contributor
timestamp: November 14, 2012, 11:02:37 pm
content: Just when I decide to buy an SSD...

author: tom66
author_rank: Super Contributor
timestamp: November 14, 2012, 11:07:55 pm
content: 1,000,000+ cycles per bit plus wear levelling can increase this by 10-20%.30-40 years data retentionI'm not seeing massive problem, and while MRAM looks neat, I could only see a need for a 2-3x increase. Modern chipsets and standards like SATA aren't fast enough for anything more.
Help request, connector identificaiton - Page 1
Forum section: electronics / general

author: Pack34
author_rank: Frequent Contributor
timestamp: November 14, 2012, 09:10:24 pm
content: I've been trying to identify a connector type.Specs of header:Pitch: 2.00mmDepth: ~5.0mmWidth: ~4.0mmLength: ~6.20mmDimension wise, I'm thinking that it's a molex microlatch header.http://www.digikey.com/product-search/en?mpart=51065-0200&vendor=23But it could be a microblade:http://www.molex.com/pdm_docs/sd/510040200_sd.pdfDoes anyone have any insight, or could possibly point me in the right direction? I could pop it off and solder onto the board but I would prefer not to.
Schematic for voltcraft vc 820 - AC voltage showing less than it should - Page 1
Forum section: electronics / general

author: rr100
author_rank: Frequent Contributor
timestamp: November 13, 2012, 10:13:00 pm
content: Can anybody help, at least with the values of the few parts on the input?It shows /1.33 compared to what it should, on AC voltage: from a few volts to mains. DC is fine and it isn't some non-rms issue - I have function generator, scope, some other multimeters ... and mains.

author: Lightages
author_rank: Unknown
timestamp: November 13, 2012, 11:56:00 pm
content: The VC820 appears to be the Uni-Trend UT60C

author: rr100
author_rank: Frequent Contributor
timestamp: November 14, 2012, 10:40:38 am
content: Thanks, that's what it is!I'm attaching the datasheet from the chip they used.Nothing suspicious from what I measured, I think I'll play with the value of R13 from Diag 21 in the file I attached (adjusting the trimmer is still a long way out).

author: Nermash
author_rank: Frequent Contributor
timestamp: November 14, 2012, 11:19:53 am
content: Actually, Voltcraft VC820 is UT60A. It doesn't have backlight and temp measurement...

author: Lightages
author_rank: Unknown
timestamp: November 14, 2012, 01:10:31 pm
content: In that case here is the correct schematic.
Young Maker makes it to MIT - Page 1
Forum section: electronics / general

author: Unknown
author_rank: Unknown
timestamp: November 20, 2012, 11:12:45 am
content: This kid is from Sierra Leone. Luckily he happens to speak English so MIT invites him. I dread to think what happens to kids who don't.The moral of the story is that most of the talented and enthusiastic kids never get noticed. If you have been through the mill like me you'd know that a little help given early goes a long way.

author: saturation
author_rank: Super Contributor
timestamp: November 20, 2012, 09:21:06 pm
content: Smart kids will always find a way to excel, legal or not. I know a lot of similar kids in countries were electronics was fairly rare and expensive, back in the 1970s, because it was worth a lot to repair, build and adapt rather than buy pre-made. Top schools often sponsor disadvantaged students in the hope they'll return to their native country to help build their infrastructure. Alas, if he's not patriotic, and most tend not to be [ what do I owe my home country that treats me like dirt, while I'm appreciated in the USA or EU?] he may not want to return to SL, and miss the cutting edge of his field of interest.

author: JonnyBoats
author_rank: Regular Contributor
timestamp: November 21, 2012, 06:23:56 am
content: This is a great story - hopefully this kid will get a good education and go far. Make you wish more kids in 1st world countries would show such initiative.>Luckily he happens to speak English so MIT invites him. I dread to think what happens to kids who don't.Actually I thought his English was far better than many of the EE graduate students at American universities who are teaching assistants for undergraduate courses. The poor American students can't understand half of what is said in class ;-)

author: poptones
author_rank: Frequent Contributor
timestamp: November 21, 2012, 09:47:46 am
content: I want to know more about this generator. It's a cardboard box with a spark plug and at one point you see him pull a screen and it starts humming. What's that about? Some sort of little engine?
What function/arbitrary generator would you recommend for about $750 US - Page 1
Forum section: electronics / general

author: IvoS
author_rank: Frequent Contributor
timestamp: November 12, 2012, 10:00:12 pm
content: Just looking to throw $750 away and buy myself a generator. I don't need crazy high frequency, I think around 60MHz should be plenty. I am looking more for a unit with good stability(low jitter), low THD and fast rise time on square wave.I know $750 is a low ball but anyway, what can I get for this money these days?

author: Smokey
author_rank: Super Contributor
timestamp: November 13, 2012, 12:17:08 am
content: http://www.tequipment.net/RigolDG4062.htmlIt's only slightly above 750

author: kg4arn
author_rank: Unknown
timestamp: November 13, 2012, 12:28:30 am
content: I have the DG4162 and I love it.Not sure about the jitter. Maybe RIGOL can give you the spec.Square wave has a 5 nanosecond rise time.There is a TTL Sync output which by myindirectmeasurements has a sub nanosecond rise-time.

author: IvoS
author_rank: Frequent Contributor
timestamp: November 13, 2012, 11:39:18 pm
content: Thanks guys, looks like the Rigol 60 meg is the winner.

author: EEVblog
author_rank: Unknown
timestamp: November 14, 2012, 12:29:28 am
content: Yeah, the Rigol would be hard to beat in that price bracket.Dave.

author: ivan747
author_rank: Super Contributor
timestamp: November 14, 2012, 01:09:55 am
content: If you want high frequency stability, you can connect an external 10MHz clock to it, I think. Dave used a frequency standard for a cellphone tower (bought on eBay) and they seem to be quite good for the money, only 50 bucks.

author: IvoS
author_rank: Frequent Contributor
timestamp: November 14, 2012, 01:38:32 am
content: It's a pretty good idea, I never thought about this. Would that really work like plug it in and that's it?

author: T4P
author_rank: Super Contributor
timestamp: November 14, 2012, 09:12:27 am
content: But the rubidium 10MHz frequency standard's price has gone up ALOT ever since he reviewed it

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 14, 2012, 11:58:06 am
content: Quote from: T4P on November 14, 2012, 09:12:27 am
Current And Electron Motion  - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: November 13, 2012, 10:01:41 pm
content: http://amasci.com/miscon/speed.html"electricity" is not a defined quantity (try to look it up). the mean drift speed of electrons is around 1mm/s but the speed that the effect of turning on the supply will propagate at not far short of the speed of light.never the less quite interesting articleThe way I think is the more voltage is applied the more electrons' speed increase because higher voltage = more energy = more speedI think an higher energy object can be more speed than a low energy one but in the drift velocity formula only appears the current not the voltage

author: Gall
author_rank: Frequent Contributor
timestamp: November 14, 2012, 01:03:53 pm
content: It gets even more interesting if you remember that the electron is not a rigid sphere.The electron in a metal wire is delocalized. That is, its wave function looks much like the oscillation everywhere in the wire. The current changes the shape of wave functions.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 14, 2012, 01:21:24 pm
content: Quote from: Gall on November 14, 2012, 01:03:53 pmnothing is rigid. everythings are made of electromagnetic waves."look and have a look again (into the tiniest or the biggest space). your sight will return to you humbled while its fatigue." - 67:3-4

author: Blofeld
author_rank: Regular Contributor
timestamp: November 14, 2012, 04:36:31 pm
content: Quote from: Sionyn on November 13, 2012, 10:01:41 pmBut the current is proportional to the voltage. Or would be if we were talking about a linear resistor. The example is about a light bulb, which makes things more complicated - the resistance of the light bulb goes up with the temperature.

author: Gall
author_rank: Frequent Contributor
timestamp: November 14, 2012, 05:45:24 pm
content: Quote from: Mechatrommer on November 14, 2012, 01:21:24 pmNot exactly, nuclear forces are not electromagnetic. Leptons aren't electromagnetic waves.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 14, 2012, 06:49:04 pm
content: but certainly not rigid aka solid. i mean nothing is purely rigid not what you thought you see it is.

author: Gall
author_rank: Frequent Contributor
timestamp: November 15, 2012, 08:12:23 am
content: Sure. The classical definition of current is the charge going through a intersection of the wire in a certain time. The charge is usually counted as number of electrons times charge of one electron. But this is only true if the electron is considered to be a point or a small symmetrical object like a sphere. The quantum definition is more complex and requires integration of wave function because there is no such thing as "electron position".
Linux embeded systems - Page 1
Forum section: electronics / general

author: Jane
author_rank: Frequent Contributor
timestamp: November 13, 2012, 07:41:02 am
content: Where can I get some info about porting Linux to embedded systems?E.g. I designed a device and would like to use it with Linux.I expect I must write few drivers so that they will communicate with my hardware( device) but what parameters the drivers should export?And what kind of drivers I should write and are there any strict procedures for writing?Thanks

author: JuKu
author_rank: Frequent Contributor
timestamp: November 13, 2012, 07:45:08 am
content: http://lwn.net/Kernel/LDD3/http://free-electrons.com/docs/kernel/

author: Gall
author_rank: Frequent Contributor
timestamp: November 13, 2012, 12:06:48 pm
content: The main site ishttp://elinux.orgIf you want something special and thus are building everything from sources by hand, look athttp://www.linuxfromscratch.org/Usually there's no need to make a kernel-side hardware driver. The kernel is able to give direct access to raw hardware in many cases.A kernel hardware module is rather simple. Usually it should provide read(), write() and ioctl() handlers for a device file. You may want to have direct access to the device's address space, use mmap() to do that.A good example is nwbutton.c found in drivers/char subdir of Linux kernel. It is short and simple.

author: poptones
author_rank: Frequent Contributor
timestamp: November 13, 2012, 04:08:16 pm
content: I find it's often easy to use an arduino with usb built in, or a usb to serial adapter, and just pipe comms through the serial port. Easy.

author: Gall
author_rank: Frequent Contributor
timestamp: November 13, 2012, 08:10:00 pm
content: Quote from: poptones on November 13, 2012, 04:08:16 pmFT2232 in bit-bang mode is even easier. Direct usage of built-in GPIO too. No drivers needed.The cases when dedicated driver is needed are:1. A FPGA or something is hooked directly to the system bus.2. GPIO is used in hard-realtime mode so that FIQ handler is needed.3. GPIOs are used in some non-standard manner (i.e. to output audio).4. A device like i2c touchscreen is used and there is no driver yet. In this case it is wise to submit the driver into Linux mainstream.

author: xygor
author_rank: Regular Contributor
timestamp: November 13, 2012, 09:13:24 pm
content: I can vouch forhttp://lwn.net/Kernel/LDD3/it's *really* good. I used it to write a network driver for a modified opencores ethernet MAC.Also came across thishttp://xillybus.com/I was interested on getting Linux running on microblaze and didn't try the xillybus device, but it solves interfacing fpga hardware to Linux and might be useful as example code for learning.