hybridfree/eevblog-posts huggingface dataset:
Global soldering stations?? - Page 1
Forum section: electronics / beginners

author: adiaz
author_rank: Newbie
timestamp: January 28, 2022, 02:39:04 pm
content: Hello! Does anyone make soldering stations that work both in the USA and EU? 120/230V 60/50hz??Thanks!!

author: BrokenYugo
author_rank: Super Contributor
timestamp: January 28, 2022, 05:09:28 pm
content: Most of the Chinese T12 clone stations use a switching supply that I think is universal input, or an external laptop brick that are usually universal input.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: January 28, 2022, 07:11:55 pm
content: If I was in the market for an extra soldering iron, It would also be a T12, but I would probably not buy the power supply from China.I've got plenty of power supplies already.If you've got a beefy lab power supply, then it could be an option to build in a small SMPS circuit to make an extra 24Vdc output as raw power for your soldering iron.

author: rpiloverbd
author_rank: Regular Contributor
timestamp: January 29, 2022, 11:43:16 am
content: Don't know about the quality but here is one:https://bluethundertechnologies.com/product/jbc-al-1a120-v-auto-feed-soldering-station/
Global Specialties PB-503 Transformer change (110V to 240V) - Page 1
Forum section: electronics / beginners

author: grayduster
author_rank: Newbie
timestamp: February 20, 2018, 10:52:27 pm
content: Hi there,Having decided to start learning electronics, I picked up a cheap second hand PB-503 from Ebay (coming all the way from the USA) to accompany the Art of Electronics course (only a tad daunting!).As expected, when it arrived, it was configured for 110V (see pictures below). I could just plug it into a step down transformer (my UK supply is 230-240V), but I assume it's better to rewire!I took some pictures below, and had a look for the schematic (best I could find washttps://ctemedia.s3.amazonaws.com/gs/discontinued/files/PB/pb-503_v1_interplex/PB-503_V1_1990_manual.pdf), I assume I can just desolder orange and red wires from the primary side of the board, solder them together with heat sink (to connect the two primary windings in series) and Bob's my mother's brother?(There does appear to be jumpers on the side of the board that's horrible to get to, but not having easy access in there, the above seemed more obvious - is there anyone far more experienced than me at this that wants to jump in to point out anything horrible about doing this, or perhaps any improvements on the above? (perhaps the fuse current rating would need altering, and might be worth re-capping?)Image album:https://imgur.com/a/RMixkMany thanks!Grayduster

author: eblc1388
author_rank: Frequent Contributor
timestamp: February 21, 2018, 12:56:29 am
content: Quote from: grayduster on February 20, 2018, 10:52:27 pmThat's part of it.Take care to study the "Before/After" connection schematic and remove also the connections between Yellow/Red and Orange/Brown wires, shown in the image below.The orange & red wire, after soldered together, still need to go to the neon lamp terminal of the switch or else you have no power ON indication.
Global test Supply authentic Mitutoyo calipers? - Page 1
Forum section: electronics / beginners

author: crippledchicken
author_rank: Contributor
timestamp: September 13, 2024, 09:41:48 pm
content: Just wondering if anyone knows if they sell authentic Mitutoyo calipers or not. Thanks!

author: thm_w
author_rank: Super Contributor
timestamp: September 13, 2024, 11:25:38 pm
content: https://www.globaltestsupply.com/product/mitutoyo-500-196-30-calliper-digimatic-encoder-technology-0-6-0-0005-0-150mm-0-01mm?ksearch_click=mitutoyo%2BcaliperIts a major american company affiliated with ITM, so yeah.Random ebay, amazon sellers will have a high chance of being fake.
Global/Local fiducial and PCB size  - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: September 22, 2021, 07:42:40 pm
content: I'm working on the PCB that will be later used to populate through pick and place (OpenPNP based) machinePlease refer to attached image where I setup local fiducials in lower corner and upper corner at 3mm from each side X, Y this is what i learned through web site resources, I just want to ensure if that sounds good?My next PCB will contain repetition of this (may be its called PCB block that contains related PCBs on one block) I want to know in that case should i put global fiducials only on the border only or local are also required? for global fiducial what are the requirements like how may and where it should be located?my last question is what is the recommended PCB block size for professional PCBA companies like if want it to be done by JLCPCB

author: Benta
author_rank: Super Contributor
timestamp: September 22, 2021, 08:16:27 pm
content: It's an interesting question, but the wrong one for us.You need to ask your PCB assembly subcontractor.

author: sairfan1
author_rank: Frequent Contributor
timestamp: September 22, 2021, 08:57:25 pm
content: Last section of my question where i asked for PCB block size could be asked to PCBAbut for local/global fiducial could be standard.
Gloves - Page 1
Forum section: electronics / beginners

author: Moriambar
author_rank: Unknown
timestamp: March 23, 2019, 07:54:52 pm
content: Hi.Recently I have been doing some work that is hard on my hands (cuts, scratches, etc…) and I don't like the idea of getting flux, residues or alcohol directly on them.Do you recommend any specific type or brand of gloves to work on a bench?Cheers

author: madires
author_rank: Super Contributor
timestamp: March 23, 2019, 08:22:19 pm
content: For protecting against liquids any cheap throwaway vinyl/nitril gloves and for more mechanical work Hase Padua Aqua.

author: Jwillis
author_rank: Super Contributor
timestamp: March 23, 2019, 11:27:14 pm
content: there are ESD gloves designed for electronics. They come coated and un-coated .Really any brand is just as good .

author: helius
author_rank: Super Contributor
timestamp: March 23, 2019, 11:30:27 pm
content: Nitrile rubber is inherently static dissipative, so all nitrile gloves are ESD. They differ in color (blue or black), and whether or not they are dusted with talc ("powder-free" or not). Some seem to be a little thicker than others.

author: GreyWoolfe
author_rank: Unknown
timestamp: March 24, 2019, 12:50:49 pm
content: I have tried a couple of different brands. I have settled on Grease Monkey talc free nitrile gloves from the local big box home improvement store. The extra large size is actually extra large and fit my hands the best of what I have tried so far. I have also worn them changing brakes and they hold up well. Unfortunately, I don't know if they are available to you.
Glue removal? - Page 1
Forum section: electronics / beginners

author: JoshLegend
author_rank: Newbie
timestamp: April 24, 2019, 07:50:17 pm
content: Hey all,I'm trying to replace a bridge rectifier which went pop inside a subwoofer. Problem is, it's covered with what looks to be some kind of glue. It's pretty hard and I was wondering if anyone knew what it actually is and how best to remove it?Thanks guys

author: johnkenyon
author_rank: Regular Contributor
timestamp: April 24, 2019, 10:45:52 pm
content: I'd measure the diameter and height. and then suss out where thepart was deployed (e.g. secondary side of a transformer, or connected to the mains side of a SM PSU), and then taking into consideration the likely current load and voltage, choose a suitable replacement.IMHO At the end of the day, if the rectifier can (1) handle the current, and (2) withstand the peak reverse voltage, taking a conservative view on ratings, you'd be hard pushed to choose a device that wouldn't suffice.

author: wraper
author_rank: Unknown
timestamp: April 24, 2019, 10:51:25 pm
content: Heating most likely will make it softer, so you can scrape it away. If you don't have a hot air station, you could put it in the oven at say 80-100oC temperature. Hair dryer might also work.

author: wraper
author_rank: Unknown
timestamp: April 24, 2019, 10:57:14 pm
content: Also you could remove solder from the pads with copper wick or desoldering tool. Then heat area around the rectifier and pull it out with tweezers while adhesive is soft.
GM328 Not Working - Page 1
Forum section: electronics / beginners

author: TroutsBane
author_rank: Newbie
timestamp: January 11, 2021, 08:42:50 pm
content: I thought I would try to build somthing past a simple breadborad circuit, so a got a GM328 component tester kit. It's all togeather now, but when I try to turn it on the screen is white, changes brightness a little, and then turns off as soon as I stop pressing the button. I notice that the red led is also not turning on, but will blink when I release the button. My meter says it is drawing 20mA ( manual says it shoud draw 30mA). I measured all the resistors and everything is in it's propper place. I am thinking it could be the pnp 9012 transistor because it gave me a hard time and I may have kept the soldering iron on it too long. Does that sound possible, or should I be looking at something else?

author: ledtester
author_rank: Super Contributor
timestamp: January 12, 2021, 05:24:01 pm
content: You might try asking in the component tester megathread:https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/6675/

author: mikerj
author_rank: Super Contributor
timestamp: January 12, 2021, 08:19:21 pm
content: Take some decent (i.e. not blurry/out of focus) pics of both the component side and the solder side and post them on here. There are several variants of those transistor testers that are called GM328 by the sellers, so it will identify the variant you have as well as help spot any component placement of soldering issues.

author: TroutsBane
author_rank: Newbie
timestamp: January 13, 2021, 04:37:33 pm
content: I took some voltage measurements on the arduino pins and was getting some wierd voltage fluctuations. I traced it back to one of the 9014 npn transistors. I am waiting for some of them to come in to see if that fixes the problem.
GMBAD inscription on a chip. what is it ? - Page 1
Forum section: electronics / beginners

author: cresstt
author_rank: Newbie
timestamp: April 16, 2019, 10:28:34 pm
content: Im trying to replace this chip from a car stereo PCB (labeled as ZCD7089).It only has an inscription of "GMBAD" and thats it.Anyone familiar with this chip ?
GMOV's, MOV's and PPTC's - Page 1
Forum section: electronics / beginners

author: aries1470
author_rank: Regular Contributor
timestamp: May 07, 2020, 03:56:33 pm
content: Hi all,I would like to ask the following, since I am not use to using these items and building for someone else.It will be sent to the USA, so it will be for a 120v system.Here is my question. The transformer I have is a 2x 120 / 240, of which is a 30VA rated one.It recommends the following fuse: 120v Primary: 500mA / 240v Primarey: 250mASo there are 2 x9v Max. Amps 3.33A, while with the fuse ratings it goes near double that.I will be putting the GMOV L/N, L/E, N/E, but can't decide onGMOV-14D171Kor GMOV-20D171K, of which to my understanding reading all over the internet in EE journals, it is best to calculate for the 120v that it can reach 170v p-p.Then the MOV's will be from the secondary windings, of which will be paralleled to out put 9v ac, but this time, there will be again on all 3 wires. My question is, what clamping rating should I get? 5A, 10 or 20A? I was looking at this one:ERZV14D220What value and voltage rating does the PPTC need to be on the mains line - before the GMOV's, instead of using the fuse?I got confused with the hold and trip. I am thinking of theLVR025K(or LVR025S does it matter?) orMF-RM025/240-2In the future, there is a possibility that it might be upgraded, state side, to up to a 50VA transformer.Thank you for your help guys.

author: aries1470
author_rank: Regular Contributor
timestamp: May 09, 2020, 11:57:09 am
content: any advise at least for the ptc?I want to change the suggested fuse to a PPTC, do I select the trip current for 500mA and hold around 250mA for the 120V option, is that correct?Thank you.
GND and 0V Connection on components? - Page 1
Forum section: electronics / beginners

author: Mint.
author_rank: Frequent Contributor
timestamp: November 14, 2011, 06:28:08 am
content: What do I connect the ground or 0V connection to on anything electronics related, such as a 555 timer? I am slightly confused about this, if it is possible can you please explain.Thanks,Minty

author: IanB
author_rank: Super Contributor
timestamp: November 14, 2011, 06:56:45 am
content: ICs like the 555 timer need to be powered in order to operate. They therefore have two power supply pins, one positive, one negative. Oftentimes the negative pin is labeled 0 V or GND. You connect the positive power supply pin to the positive power supply rail in your circuit and you connect the negative power supply pin to the negative power supply rail in your circuit. If you are powering your circuit from a battery these connections will come from the two terminals of the battery. Check the datasheet or application notes about the need for decoupling or bypass capacitors across the power supply pins.

author: johnboxall
author_rank: Unknown
timestamp: November 14, 2011, 07:09:28 am
content: Quote from: MintyCondition on November 14, 2011, 06:28:08 amIf you're interested in the 555 I wrote a small introduction about it here >http://wp.me/pQmjR-1l2

author: aparlett
author_rank: Regular Contributor
timestamp: November 16, 2011, 12:34:44 am
content: I think they re the same, but I have come across the term virtual ground in my studies, which is point where the voltage is zero between two points.

author: Neilm
author_rank: Super Contributor
timestamp: November 16, 2011, 07:03:24 pm
content: Quote from: aparlett on November 16, 2011, 12:34:44 amGND and 0V are often used interchangeably but there is a subtle difference. This difference is only applicable if you are doing things with safety / EMC and are concerned with exactly where current is flowing in a circuit - not really topics for beginners (or advanced engineers unless they are really unlucky).The term "virtual earth" or "virtual ground" is "a node of the circuit that is maintained at a steady reference potential, without being connected directly to the reference potential". The term mostly found in op amps when one of the inputs (usually the +) is connected to 0V. Due to the way an op- amp works, the - terminal is held at the same potential - (0V) without a direct connection.Neil
GNSS antenna detection - Page 1
Forum section: electronics / beginners

author: tox3
author_rank: Contributor
timestamp: November 13, 2021, 09:26:10 am
content: Hello, I am trying to design open and short detection for active GNSS antenna.I expected antenna_open to go low at 1.7mA, but it does go low at 19mA.Antenna short is close enough to expected 50mA.Currently I am using ST LMV358LVoltage is 3VWhat am I missing here?

author: thinkfat
author_rank: Unknown
timestamp: November 13, 2021, 09:35:20 am
content: The supply voltage is?

author: tox3
author_rank: Contributor
timestamp: November 13, 2021, 09:36:14 am
content: 3V

author: Renate
author_rank: Super Contributor
timestamp: November 14, 2021, 11:50:55 am
content: Your numbers are correct.I don't think your op amps are happy with differential input voltage and are fighting.Easy test: Disconnect one leg of the input of one opamp. Does the other one work correctly? Now try the other way.(Because you're using op amps and not comparators.)Me? I'd use a INA226 and an ATTiny85, which is massive overkill, but I've got the parts on hand.
GNSS/GPS - Page 1
Forum section: electronics / beginners

author: sgi199
author_rank: Contributor
timestamp: September 23, 2019, 04:09:50 am
content: Recently, I bought an Ericsson GNSS antenna in the idle fish of Taobao Net and used it on the taming clock. The result is satisfactory indoors. Teachers, thank you!Such a good baby, I personally think it should be recommended to electronic enthusiasts. I bought another spare. In addition, I am a novice, registered for several days. Read the article about repairing rubidium clock, also have experience and harvest! Thank you all for your predecessors! Thank you!
GNU Radio Hack RF FFT example - Page 1
Forum section: electronics / beginners

author: martinwag
author_rank: Newbie
timestamp: May 20, 2018, 02:26:13 pm
content: Hi @all,I'm trying to go trough the Hack RF tutorial fromhttps://greatscottgadgets.com/sdr/1/. In the first video he is implementing FFT over FM radio band.As mentioned in the errata, I've changed "Options" to WX GUI. Otherwise the settings are as explained. Howver, when I run the graph, only a icon with a question mark appers in the task bar, but nothing happens otherwise. (https://ibb.co/jY8yBx).When following the warning and adding a throttle block, I get a error that some things are not connected... (https://ibb.co/jRGwyc).It doesn't make a difference if RF hardware is connected or not.Any ideas?Thank you for your help!regards,MartinPS: I've tried asking this on the GNU Radio mailing list, however my mail didn't show up, even after registring- Course: "Software Defined Radio with HackRF"https://greatscottgadgets.com/sdr/- Software: GNUradio live DVD ubuntu-16.04.2-desktop-amd64-gnuradio-3.7.11.iso- Hardware: CCC Camp 2015 hackrf compatible (https://rad1o.badge.events.ccc.de/start)

author: scatha
author_rank: Regular Contributor
timestamp: May 21, 2018, 07:54:34 am
content: It looks like the hardware source block and the WX FFT sink are greyed out, ie. disabled. Right mouse click on both of them and make sure that they are enabled.You should never need a throttle block if your flowgraph has a (enabled) hardware source or sink.
Go find your ocilloscope today!! - Page 1
Forum section: electronics / beginners

author: TVman
author_rank: Frequent Contributor
timestamp: April 02, 2014, 04:25:36 pm
content: "everyone" says "I can't find any good oscopes anywhere"Look on ebay....http://www.ebay.com/If you can't find one:https://www.eevblog.com/forum/blog/eevblog-498-how-to-get-a-$50-oscilloscope-on-ebay/GD luck!
Going Above A Switch's Current Rating Okay? - Page 1
Forum section: electronics / beginners

author: ruthsarian
author_rank: Contributor
timestamp: April 15, 2020, 12:16:38 am
content: I have a small, DPDT push button switch rated for 100mA @ 30VDC. The nature of how this switch is being used means it will never be switched on or off while power is being applied; power will only be applied AFTER the switch has been put into position.With that in mind, would it be acceptable to run a higher current, say 500mA @ 5VDC, across that switch?I've tried reading up on the subject and most of what I've read focuses on what happens when a during switching action while power is being applied; how it handles the arcing, etc., and that those scenarios weigh heavily on the current rating of a switch. But if the switch isn't being switched while power is applied, would it then be acceptable to run a higher current through the switch?Thanks

author: Manul
author_rank: Super Contributor
timestamp: April 15, 2020, 01:00:02 am
content: That is hard to say, and mostly depends if it is for hobby use or a product. For a commercial product it is not a good idea. Otherwise it should be just fine.There is such a thing as contact resistance. Lets say it is 0.1 Ohms. So for 100mA there is 1mW of power dissipation. For 500mA it is 25mW. As you can see it increased 25 times (current square dependency). There may be accidental contact contamination and increase of resistance. So more dissipation. If this dissipation is ever enough to noticebly increase contact temperature there may be degradation of contact surface which will increase resistance and dissipation even more. And basically lead into degradation runaway and failure.For sure 500mA will not cause an immediate failure. But reliability issue - possibly.
Going cross-eyed trying to map SMD PCBs - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: August 07, 2018, 06:47:07 am
content: For instance lately I'm mapping out a 2"x2" doubled sided PCB with plenty of BJTs, 2 ICs, voltage reference ICs, etc.I'm using a 30x loupe and DMM, it's like entering some mini-model/road map. Getting tiring and boring after a while tho.It would quicker to take a nice photo, then take it all off with the hotair gun, then photo the bare PCB, and put it back together.I'm just doing this for fun/experience.

author: CJay
author_rank: Super Contributor
timestamp: August 07, 2018, 10:33:25 am
content: Take photos of both sides, print them out *large*.Any connections you can't work out quickly from the pics, meter out.A graphics package will help as you can flood fill tracks or PCB, alter contrast, change colour depth etc to make tracks stand out (though some PCB coatings make it damn difficult)Helps if you can identify ICs, devices etc. as there's only so many ways you can connect the majority of non programmable devices and you can quickly identify then ignore power rails until you decide to make a new PCB.If you can sacrifice a board then as you say, stripping the board is very helpful, you can, after careful photography, then sand it lightly to remove solder masks and expose tracks, vias etc. which makes it much easier to trace out.

author: Buriedcode
author_rank: Super Contributor
timestamp: August 07, 2018, 05:53:18 pm
content: You could always take (large, high res) photos of both sides of the board - trying to get the image the same size, then mirror the bottom, make both images transparent transparent and add them together in your preferred photo/image editing software - I used gimp for this. As CJay suggested - enhancing the contrast of the tracks will help as well. I've done this on a number of newer guitar pedals to trace out the schem - it really does help.

author: lordvader88
author_rank: Frequent Contributor
timestamp: August 07, 2018, 07:24:59 pm
content: Yeah I have to get a working camera and make a stand. And some day soon a USB microscope.There's no pictures on the net for this pcb

author: Buriedcode
author_rank: Super Contributor
timestamp: August 07, 2018, 08:20:41 pm
content: Even a phone camera will do. As long as you hold it roughly the same height above a surface, you can scale it in software - I've only done it without a stand and it works.

author: TERRA Operative
author_rank: Super Contributor
timestamp: August 08, 2018, 05:33:50 am
content: The 'Office Lens' smart phone app is great for taking photos of stuff like this.It detects the edges and automatically corrects the image to be a perfect square.I use it all the time for takung screenshots of things without a print screen button. Works great.
Going down a regenerative rabbit hole in search of a Quiet circuit - Page 1
Forum section: electronics / beginners

author: jonovid
author_rank: Super Contributor
timestamp: January 23, 2023, 08:53:40 pm
content: before starting something that maybe a pointless exercise? do you know the answer to this? as I do not.for most of us that can still remember, and are somewhat familiar with the single transistor 27MHz regenerative receivers used in toy walkie talkies of the 1980sand the extremely loud hissing when no in-coming signal was been received.the question I have for the forum is this. can the current draw of a single transistor regenerative receiver determine its received signal strength?assuming the regenerative circuit is stable. if so a squelch type of noise gate can be added to the regenerative circuit audio output by monitoring the regenerative supply voltage.the particular regenerative circuit schematic I had in mind was the VHF regenerative receiver in this video.its simple to make and get going. as the base of any regenerative experiment.and if by adding a experimental DIY squelch circuit it?its not so Mach finding or designing a squelch noise gate design. but determining if a single transistor regenerative receiver changes its current draw based on received signal strength?if yes , I am looking at a 2 or more transistor or op-amp schmitt trigger with a voltage reference circuit. I can figure it out my myself.and yes going down a regenerative rabbit hole in search of a quiet circuit that also adds to the component count.if no! I have saved myself a pointless exercise and also by posting here others also.update-wrong forum thread..? perhaps a completed circuit is needed before posting hypothetical questions

author: Terry Bites
author_rank: Super Contributor
timestamp: January 24, 2023, 12:54:40 pm
content: There's no reason not to add audio squelch. Of course, it won't let you operate in CW mode.Then CW is a minority interest these days.There has been a resurgence interest in regen for wireless data systems.www.cool386.com/arc/arc.htmlDescribed here is a method for auto quench based on detection of excessive AF amplitude. It works like AGC. Instead of controlling the receiver gain it controls the magnitude of the quench oscillator injection. Worth experimenting with. (SA575 could do regen control and audio squelch).Check this out.www.eevblog.com/forum/beginners/super-regenerative-reciever/
Going nuts testing gates - Page 1
Forum section: electronics / beginners

author: gkmaia
author_rank: Frequent Contributor
timestamp: April 15, 2019, 07:41:24 pm
content: I've been able to test gates this way in the past. But yesterday nothing worked.The LED in the right is connected to VCC.The one in the middle is connected to pin 12 therefor should be HIGH, but it is not. Instead outputs 150mVThe one in the left is LOW. And should be as pins 9,10 & 11 are connected to VCC.I did this test with several different gates types. The one on the photo is a 74ls12 and I tested 5 different ICs brand new. Same result.My gate outputs no mater what the input is always output around 0.150V.I am certainly missing something here. It is not possible almost 20 brand new ICs are faulty.

author: rstofer
author_rank: Super Contributor
timestamp: April 15, 2019, 07:51:04 pm
content: I'm not entirely clear on where pin 1 is but I'm guessing lower left corner of the DIP as shown in the photo.You pulled pin 1 high and left pins 2 & 13 floating which means high (probably). All 3 inputs are high, the output should be low.You should never leave pins floating.

author: RoGeorge
author_rank: Super Contributor
timestamp: April 15, 2019, 07:51:42 pm
content: The datasheet says 7412 has open collector outputs. That means the output of the gate can only pull down (GND), it can not pull up (to Vcc).You need a resistor to V+ for each gate output pin (6, 8, 12)Alternatively, for testing you can connect the LED to the Vcc instead of GND (with LED anode to Vcc), so you won't need extra resistors for each gate output.

author: gkmaia
author_rank: Frequent Contributor
timestamp: April 15, 2019, 08:12:47 pm
content: Quote from: RoGeorge on April 15, 2019, 07:51:42 pmThanks so much! Will try that when I am back home!

author: gkmaia
author_rank: Frequent Contributor
timestamp: April 16, 2019, 09:01:24 am
content: It worked! Thanks guys!
Going over rated Power Dissipation of MOSFET - Page 1
Forum section: electronics / beginners

author: help_me_pick_username
author_rank: Contributor
timestamp: November 08, 2019, 02:46:16 am
content: I have a 30N06l which is rated for a power dissipation of 79w. If I have adequate cooling, can I dissipate more heat with the MOSFET?

author: ejeffrey
author_rank: Super Contributor
timestamp: November 08, 2019, 04:53:08 am
content: 79 W is only with the case at 25C -- i.e., perfect heat sinking. Unless you have chilled water cooling you aren't going to be able to even reach 79W.

author: wraper
author_rank: Unknown
timestamp: November 08, 2019, 05:14:14 am
content: Under realistic (good) cooling don't push more than 30W out of it if you want to have any reliability. And by good I mean either actively cooled with fan or just HUGE heatsink.

author: viperidae
author_rank: Frequent Contributor
timestamp: November 08, 2019, 06:12:14 am
content: You'd need a heatsink at -15 degrees to run at 79W. The case to heatsink thermal resistance is 0.5C/W, so to keep the case at 25C the heatsink needs to be 79*0.5C lower.

author: help_me_pick_username
author_rank: Contributor
timestamp: November 08, 2019, 12:17:17 pm
content: Two broken 30N06Ls later, here we are. Thanks for the info guys, at least I learnt some more about how to read a datasheet properly.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 09, 2019, 06:03:26 am
content: For how long?(Datasheet also tells: see safe operating area curve, with times given.)Tim
Going overboard with ESD protection? How much tooling is enough? - Page 1
Forum section: electronics / beginners

author: armaguedes
author_rank: Newbie
timestamp: January 13, 2022, 04:45:39 pm
content: Good afternoon everyone.After a ~10 year hiatus, I have now gotten back into hobbyist electronics, and have started re-tooling the bench, as much has either gone missing, or somehow got damaged while in storage. One of the things I am starting with -- and which I never concerned myself with at the time -- is electrostatic protection.Now, I'm already planning to buy a properESD mat, and I found a wrist strap in my boxes (it's one of those with metal segments, much like a watch bracelet, instead of a velcro strap, if this is relevant).If it matters, my workbench is an IKEA wooden kitchen benchtop, and the flooring is hardwood, but covered in an IKEA thick plastic protection mat. I almost-always wear shoes, with "normal rubber soles".Now, is it worth it to buy ESD foam to store transistors and ICs in (I know it's not expensive, and it's not a consumable)? One would think junctioned semiconductors should be impaled in this foam, but the likes of Digikey and Mouser sell them in bulk or on tape, and there are plenty of shops selling "component boxes", which is also how I found my own old trannies stored. Furthermore, should we store diodes in ESD foam? Or do single-junction components behave differently?How about ESD bags (re-sealable)? These make sense to store projects, but should I get the pink, blue, or black bags? Or is there another, better, search term?What are your thoughts on ESD handtools? Presently I'm sticking with my (aluminium-and-steel) electronics screwdriver kit from iFixit, but I've seen ESD-rated flush cutters from Knipex and Xuron, and ESD-rated precision screwdrivers from Wera. And ESD PCB sweeping brushes? I assume the path-to-earth for these things relies on your body's conductivity and a wrist strap.While I'd like to save money like the next guy over, I'd also rather invest a bit upfront -- except for the bags, the items above are not even consumables -- and prevent smoked parts, or intermittent faults. How much is too much? As I understand things, the mat and the bracelet are the basic / essential tools, but how about the rest? Am I missing any other tools? Any recommendations?Thanks!-b

author: m k
author_rank: Super Contributor
timestamp: January 15, 2022, 05:49:38 pm
content: Wrist wrap is a must.Grounded is not a must but no potential difference is.Plain matte printer paper can substitute ESD mat for starters.Just don't do incredibly sensitive stuff.If you do stuff with plastic clothes sitting in plastic covered chair with plastic wheels on plastic floor with plastic shoe soles, don't move much.
Going to production, make Nano -atmega328p program, how to do it? - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: March 21, 2019, 03:22:23 pm
content: 1. I have a arduino nano board & made a small project on it. Its running succesfully.2. Now i want to go to program 100 more MCU and make own board which is customized and has MCU on it?3. How can i program MCU alone on my customized board. I dont need any FTDI ic or usb port on my board.4. Also I dont need external crystal? How I can do change in arduino programming so that Atmega uses its internal oscillator only.

author: Moriambar
author_rank: Unknown
timestamp: March 21, 2019, 03:34:15 pm
content: Quote from: Vindhyachal.takniki on March 21, 2019, 03:22:23 pmGood for you!QuoteIs this a question? Anyway if you want to design a board around an MCU I suggest first determining which MCU you need (could be an ATTiny, an ATMega, depending on gpio and peripherals needed - I only mention Atmel chips since using the nano, imo, is easier you want to use those). then you sketch your circuit and prepare the pcb layout but:QuoteIf you don't want to program the MCU outside of the board but you want to solder them first, then you're gonna need to put specific programming headers that interface with the specific pins of your cpu in your PCB design. An Atmel MCU can be programmed via various tools, even via another arduino. You don't need an extra IC or any USB ports. Online you find tons of examples with many different programmers (TinyUsb, Arduino, ...). I, instead, prefer to program the chips beforehand, and then test and solder them. The process is similar but I don't have programming headers on the pcbs.You can use the arduino IDE to program other atmel chips (and many other chips too), just by downloading specific libraries such as TinyCore for ATTiny and so on.QuoteI never needed an external crystal and I think there are few chips (but I actually don't know) that absolutely need one. If the internal oscillator is "good enough" for you, no need for anything else. How to use the internal oscillator depends on which IDE and possibly libraries you use to program the chip.

author: Kasper
author_rank: Frequent Contributor
timestamp: March 21, 2019, 03:36:09 pm
content: This covers a basic way to do it:https://www.arduino.cc/en/Tutorial/ArduinoToBreadboard

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: March 23, 2019, 04:24:45 am
content: this will try & see :https://www.arduino.cc/en/Tutorial/ArduinoToBreadboard

author: boffin
author_rank: Unknown
timestamp: March 23, 2019, 04:45:45 am
content: Quote from: Vindhyachal.takniki on March 21, 2019, 03:22:23 pmThis covers the ATMEGA and ATTINY nicelyhttps://snafu.ca/programming-atmega-and-attiny-chips-using-the-arduino-ide/
Gold fingers design best practices - Page 1
Forum section: electronics / beginners

author: matthuszagh
author_rank: Frequent Contributor
timestamp: January 11, 2023, 05:49:48 pm
content: I'm designing a PCB with gold fingers. I've never done this before and the cost is quite high so I'd like to make sure I get the design right the first time. Here's what I understand so far:1. gold plating thickness determines number of insertion / removal cycles. It seems like 30uin over a base layer of nickel is typical.2. beveling is often done to ease insertion. 20, 30, 45deg are common. Make sure to give enough edge space beyond the end of the pads for the bevel.3. Keep soldermask away from the edge connectors (i.e., no soldermask between pads).4. I think cost is tightly coupled with total amount of gold deposited. I saw one recommendation that trace connections to the pad be small to minimize cost.Anything else really major I'm missing? I've attached an image of a portion of the edge connector part of the PCB. I'd previously used the pad connection method 2-... but am considering migrating to the connection method shown on the leftmost pad (thin trace to pad), to minimize cost. That's a 10mil trace. Thoughts? I'll be using PCBway for this. Anything in particular I should verify with them to ensure things are done correctly?Thanks.

author: Terry Bites
author_rank: Super Contributor
timestamp: January 14, 2023, 04:14:27 pm
content: https://getyarn.io/yarn-clip/340a7940-8030-4264-8ad9-f142332e858a

author: matthuszagh
author_rank: Frequent Contributor
timestamp: January 14, 2023, 10:10:12 pm
content: Quote from: Terry Bites on January 14, 2023, 04:14:27 pmI'm confused.
Gold Plated circular pads - Page 1
Forum section: electronics / beginners

author: Nikos A.
author_rank: Regular Contributor
timestamp: January 06, 2019, 03:09:26 pm
content: Hi everyone,Could someone explain me what are these gold plated circular pads and what is theis purpose?Thanks in advanceNick

author: Nusa
author_rank: Super Contributor
timestamp: January 06, 2019, 03:23:49 pm
content: Test points. Presumably for automated testing after assembly, since they're unlabeled. Only humans need labels.

author: Nikos A.
author_rank: Regular Contributor
timestamp: January 06, 2019, 03:38:01 pm
content: Thank you Nusa!!

author: Nikos A.
author_rank: Regular Contributor
timestamp: January 06, 2019, 06:37:40 pm
content: The automated testing requires a unique Gerber file with the Test Points in order to access these?

author: Kasper
author_rank: Frequent Contributor
timestamp: January 06, 2019, 07:16:00 pm
content: You can also make your own test jig to contact those pads for programming and testing.https://learn.adafruit.com/how-to-make-a-pogo-pin-test-jig

author: Nikos A.
author_rank: Regular Contributor
timestamp: January 07, 2019, 08:22:19 am
content: Thank you guys!!!
"Gold plated" connectors: how tell which ones are fake? - Page 1
Forum section: electronics / beginners

author: Moriambar
author_rank: Unknown
timestamp: May 28, 2021, 11:39:01 am
content: Hi,it's just a question that popped up in my mind. I have "inherited" some lab equipment, containing banana plugs & similar. Some of them are gold plated, or at least they're gold coloured and shiny.Is there any non-destructive way to tell whether they really are gold or are some kind of chinese ripoff?Btw, they're all good to me, I do not need gold plated anything basically, but I wanted to know out of curiosity

author: richard.cs
author_rank: Super Contributor
timestamp: May 28, 2021, 06:09:59 pm
content: Generally fake-gold-plated stuff is rare. Most electrical things that look like gold and don't tarnish horribly in a few weeks really are gold. What varies is the quality and thickness of the plating. Cheap items are likely to have a very thin layer of gold, with minimum prep. It might have surface imperfections and in extreme cases flake off. Proper gold plated items will not just have thicker gold but will have a series of layers of different metals with chemical cleaning steps in between.

author: tooki
author_rank: Super Contributor
timestamp: May 28, 2021, 06:12:17 pm
content: I got some Chinese “gold plated” headers that are basically unsolderable. I had to throw them out.I think fake gold plating isn’t as rare as you think.
goldpin connectors - what's the proper name - Page 1
Forum section: electronics / beginners

author: glatocha
author_rank: Regular Contributor
timestamp: May 31, 2013, 07:48:43 am
content: Sorry for such a lame question.What is the proper name for the most popular goldpin 0.1" connector. Those that all of us using for connect to breadboard and so on so on.I was digging suppliers today for them, but apparently I don't know how they are called

author: amyk
author_rank: Super Contributor
timestamp: May 31, 2013, 08:10:13 am
content: headers

author: JackOfVA
author_rank: Unknown
timestamp: May 31, 2013, 10:06:33 am
content: Also called pin headers - the square pins are 0.025" and the spacing may be called out as 0.1" or 2.54 mm.DigiKey part numbers ... a 4 pin socket is S7037-ND for example. That will give you a link to DigiKey's catalog with other sizes of headers.Checkhttp://www.sullinscorp.com/catalogs/78_Page80-81_HEADER_.100_2.54mm_FEMALE.pdffor one high quality manufacturer of header sockets.For the male pins, a 4-pin from DK is P/N S1251E-04-ND and you can find other links there.I buy the male pins in strips of 36 and break them into the needed lengths - much cheaper per pin than buying 12 each 3 pin headers, for example.Also, note that the pins and sockets are available in various depths/heights.

author: Paul Price
author_rank: Super Contributor
timestamp: May 31, 2013, 10:54:37 am
content: IDH bed of nails inusulation displacment headers/connectors.
GolTek Bode Plotter PC SW (for DS1000E/D and/or Hantek DDS3x25) - Page 1
Forum section: electronics / beginners

author: Mechatrommer
author_rank: Super Contributor
timestamp: March 23, 2012, 09:56:47 am
content: here is "not so completed" PC SW to sweep control DDS3x25 (optional, can also use (default to) external FG in manual/interval mode)), and capture the signal from DS1000E/D series. "how to" is available from Help menu. its in trial version, if you like it you may upgrade to "full" version.http://www.soasystem.com/eng/goltek/gtbode100.zip(2MB size)

author: Mechatrommer
author_rank: Super Contributor
timestamp: March 30, 2012, 10:45:13 am
content: update v101 to the above is now available... patch and read the note.txt before run. cheers.
good(ich) soldering station for high termal mass (80 to 100 euro) - Page 1
Forum section: electronics / beginners

author: loordgek
author_rank: Contributor
timestamp: November 18, 2018, 08:52:28 pm
content: hii need to replace caps on a tv and a few are under a heat sink and i need to desolder the heat sink,but my 30 watt soldering iron is not going to do it.i am looking at xytronic soldering station lf-1600. (80 watt)is that high enough

author: FriedMule
author_rank: Frequent Contributor
timestamp: November 18, 2018, 09:18:30 pm
content: I think that it all depends on the thermal mass and the quality of the soldering iron.If you only have to manage that job once, you may look at something build yourself of the high heat type.

author: mvs
author_rank: Frequent Contributor
timestamp: November 19, 2018, 12:06:25 am
content: Quote from: loordgek on November 18, 2018, 08:52:28 pmIts just yet another Hakko 900 series clone...You may find it good, but after using cartridge based systems (Hakko T12 and JBC) i would not consider to buy it anymore.
Good (cheep) PCB manufacturer - Page 1
Forum section: electronics / beginners

author: edybond
author_rank: Newbie
timestamp: December 15, 2010, 08:17:46 pm
content: Hi,can any one tell me where I can order pcb for good price?

author: tyblu
author_rank: Frequent Contributor
timestamp: December 15, 2010, 09:34:00 pm
content: Hello,you can find this info here:https://www.eevblog.com/forum/index.php?topic=1324.0you can search the forums using the box at the top right. I used the terms "pcb manufacturer" to find the above.

author: fitter108
author_rank: Contributor
timestamp: December 19, 2010, 01:27:35 pm
content: I had some pcbs made at PCB cart in china and they where great at a great price. I did have a issue with the boards solder mask on the front side not populated and no traces but it was my fault due to inexperience and ignorance. That is how we learn right. I still used the boards and work fine just not as pretty as i wanted. I have made changes to the drawing and will reorder soon. Make sure if you have anything out of the ordinary that you put a fabnote layer with instructions as someone on here told me to do. It would have fixed my issue. The manufacturer can not read our minds. My board ordering experience was very godd and exciting. I am looking forward to ordering more. My post was awhile back and named ( issue with pcb order ) in the beginners section where I asked the forum what I did wrong. Hope this helps

author: dadler
author_rank: Unknown
timestamp: March 08, 2016, 07:57:10 am
content: Quote from: anson-IT on March 08, 2016, 07:51:07 amDude, you just posted an advertisement in a 5+ year old thread...

author: Dave Atom
author_rank: Contributor
timestamp: March 14, 2016, 11:54:52 am
content: Quote from: dadler on March 08, 2016, 07:57:10 amI wanted to add to the irony

author: Semonycal
author_rank: Newbie
timestamp: March 16, 2016, 08:47:33 am
content: Just got the new MOT circuit board (10 boards) quoted bywww.pcbway.com/cc. Price is $53 from Donald Trump's favorite place, China, as compared to $225 (approx) from Advanced Circuits in Colorado. Since I am not really in a hurry I am going to try China. I had some done in China (different company) a couple of years ago and they were great. Thinking of going to more surface mount and also having the assembly done in China. That would boost my effective hourly rate through the roof - up around $500. I don't particularly love to solder and am fine with some Chinese chick doing it for me. Less of my manual labor could also mean I could cut the price and go for world domination.
Good Batteries / Bad Batteries Storage Help? - Page 1
Forum section: electronics / beginners

author: XMA
author_rank: Contributor
timestamp: April 04, 2018, 05:55:52 pm
content: Hello, so id like some opinions on how I store my batteries. as u can see in the blue bottle I store my dead batteries, that are 1.3v or under but output around nothing in amps."I measure with a multimeter", in the plastic container I store good batteries. so im wondering if my way of storing the dead batteries is bad? as they might touch each other's contacts resulting in a short circuit or so.

author: Audioguru
author_rank: Super Contributor
timestamp: April 04, 2018, 10:50:35 pm
content: Your bad batteries produce very low current so they cannot cause damage from too much current.Their contacts on each end are impossible to short-circuit anyway.The bad batteries might leak their chemicals. Get rid of them soon.

author: Brumby
author_rank: Unknown
timestamp: April 04, 2018, 11:58:43 pm
content: I store my old batteries in a zip lock bag and they end up jumbled around, just like your bottle. Periodically, I take it down to Aldi, where they have a battery recycle bin and just empty it into there. What's inside that bin makes your collection and my collection trivial - yet I know of no issues doing that.Without the ability to deliver notable current, there's no electrical issue.Leaking chemistry, however, could become messy. Find yourself a battery recycle/dropoff centre and get rid of them.
Good books or tutorials for PCB design - Page 1
Forum section: electronics / beginners

author: BytesGuy
author_rank: Regular Contributor
timestamp: November 10, 2014, 12:01:44 pm
content: Could anyone reccomend any good books or tutorials for people who are new to PCB design?I have a very complicated through-hole design I would love to get on a PCB, but I don't feel that confident with just mucking about with diptrace till it works

author: tautech
author_rank: Super Contributor
timestamp: November 10, 2014, 12:34:38 pm
content: Our Dave used to work for Altium and has a tutorial in his Wiki:http://www.eevblog.com/wiki/index.php?title=Online_Electronics_Tutorials_and_Books

author: EEVblog
author_rank: Unknown
timestamp: November 10, 2014, 12:41:15 pm
content: Quote from: tautech on November 10, 2014, 12:34:38 pmBTW, that tutorial had nothing to do with Altium. I did that 6 years before I ever worked there.

author: tautech
author_rank: Super Contributor
timestamp: November 10, 2014, 12:47:59 pm
content: Quote from: EEVblog on November 10, 2014, 12:41:15 pmSorry Dave....poorly worded.I studied it a year ago and thought it was a very sound resource.

author: Syntax_Error
author_rank: Regular Contributor
timestamp: November 11, 2014, 06:34:43 pm
content: After reading Dave's great PCB design tutorial, check out:https://www.google.com/search?q=ti+pcb+design+guidelines+for+reduced+emi&oq=TI+pcb+design+&aqs=chrome.3.69i57j0l5.9220j0j7&sourceid=chrome&es_sm=93&ie=UTF-8The first PDF link is pretty good. I haven't checked out the others yet.Also,http://www.analog.com/library/analogdialogue/archives/43-09/linear_circuit_design_handbook.htmlChapter 12 deals explicitly with PCBs.

author: BytesGuy
author_rank: Regular Contributor
timestamp: November 20, 2014, 01:59:00 am
content: Thanks all, lots of good stuff here to keep me busy