hybridfree/eevblog-posts huggingface dataset:
any good book on how to test electronic components? - Page 1
Forum section: electronics / beginners

author: kasumyku
author_rank: Regular Contributor
timestamp: April 11, 2013, 12:06:33 pm
content: I'm trying to find a good book on how to test electronic components.I searched all over internet but its keep popping up this book by Jestyne Yong, which I checked it and I don''t like it at all.Can anyone give me some book names to look for...Thanks!!

author: Simon
author_rank: Unknown
timestamp: April 11, 2013, 12:08:09 pm
content: That is not a subject too many books cover. What are you trying to test ? The best approach is to understand how the part works so that you can test is for an expected result. If you get what you expect it is good if not it fails

author: kasumyku
author_rank: Regular Contributor
timestamp: April 11, 2013, 12:23:21 pm
content: I am looking for basic components testing techniques starting with capacitors, diodes to relays, rectifiers, transistors and so on.

author: madires
author_rank: Super Contributor
timestamp: April 11, 2013, 12:43:53 pm
content: Quote from: kasumyku on April 11, 2013, 12:23:21 pmCheck out the Transistor Tester athttp://www.mikrocontroller.net/svnbrowser/transistortester/and start with the documentation /Doku/trunk/pdftex/english/ttester.pdf.

author: peps1
author_rank: Regular Contributor
timestamp: April 11, 2013, 12:59:36 pm
content: Iv never seen a book that just covers the testing of components.But getting a good understanding of how the part work will stand you in good stead.Components like capacitors, diodes relays, rectifiers, transistors and so on can all be tested to a point with a good multimeter(with a transistor tester, and capacitance meter built in) and google.Id also really recommend this book if your new to electronics:Make: Electronics: Learning Through Discovery

author: jpb
author_rank: Super Contributor
timestamp: April 11, 2013, 01:04:19 pm
content: How about this one :http://www.amazon.co.uk/How-Test-Almost-Anything-Electronic/dp/0830641270/ref=pd_bxgy_b_img_yI've no idea if it is any good but it seems to cover the area you're interested in.Though looking at the reviews they are mainly negative and it doesn't really cover transistor testing.

author: smashedProton
author_rank: Frequent Contributor
timestamp: April 11, 2013, 02:27:57 pm
content: Use an octopus to find the IV characnatistics of it. That will thell you a bunch of stuff
Any idea what this chip is? - Page 1
Forum section: electronics / beginners

author: Matty
author_rank: Contributor
timestamp: August 08, 2017, 11:39:39 am
content: This is just out of curiosity... I'll probably never use itThis came from a box-o-junk, where it 'could' be related to CRT TVs.The package says is a TI 96C61XM, but I can not find it on their website. The bag was dated Dec 1999.Also the packaging looks odd: E.G. pins cut off the end, and it looks like its badly molded.

author: DTJ
author_rank: Super Contributor
timestamp: August 08, 2017, 11:45:30 am
content: This bloke reckons they are an opto-coupler.http://markhindes.easywebstore.co.uk/96C61XM_AR2HL.aspx
Any idea what this IC is ? - Page 1
Forum section: electronics / beginners

author: RichardM
author_rank: Frequent Contributor
timestamp: January 08, 2021, 12:04:33 pm
content: Hi AllI have several ICs marked S7815 2114-6. 18pin PDIP ? I have googled a bit without much luck.RegardsRichard

author: Benta
author_rank: Super Contributor
timestamp: January 08, 2021, 12:15:50 pm
content: 1024 x 4 SRAMs. 7815 is the data code, 2114 the part number.

author: Syntax Error
author_rank: Frequent Contributor
timestamp: January 08, 2021, 12:16:33 pm
content: Me thinks it's a 2114 static ram chip from 1978.Organised as 4 bit x 1024.https://www.petervis.com/Datasheets/2114_Static_RAM/2114_Static_RAM.htmlHang onto those, there are retro micro computer guys on here that would be interested in them.

author: RichardM
author_rank: Frequent Contributor
timestamp: January 08, 2021, 12:30:58 pm
content: Ok, thanks guys. I have a number of them. I bought a random box of components for $75. I was most interested in the uv EPROMs. Maybe I could recoup a few $$Richard

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: January 08, 2021, 02:17:02 pm
content: Commodore 64 and VIC-20 color RAM, and VIC-20 main RAM. They don't fail all that often IME but there's a demand for sure.

author: Syntax Error
author_rank: Frequent Contributor
timestamp: January 08, 2021, 02:24:04 pm
content: Add to that list Sinclair ZX80s and early edition ZX81s.

author: Terry Bites
author_rank: Super Contributor
timestamp: January 08, 2021, 03:21:22 pm
content: Knock yourself out with the whole datasheet.Then gently waft the chips into the wee bin.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: January 08, 2021, 03:48:09 pm
content: Crikey, I'm old. That's the first IC I ever came across.

author: SeanB
author_rank: Super Contributor
timestamp: January 08, 2021, 03:59:26 pm
content: There are a few YT creators in the UK though who restore old computers, and would love them, so instead pop in an envelope and send there. Noel's Retro lab comes to mind, and he often replaces these DRAM and SRAM chips in old computers to repair them.https://www.youtube.com/channel/UC2-SP1bYi3ueKlVU7I75wFwfor the channel, and you can get his contact details.

author: RichardM
author_rank: Frequent Contributor
timestamp: January 09, 2021, 03:33:46 am
content: I think postage from Aust would probably be prohibitive.I also have what looks like a Western Digital IC that I am unsure about.

author: wraper
author_rank: Unknown
timestamp: January 09, 2021, 03:37:29 am
content: Quote from: RichardM on January 09, 2021, 03:33:46 amPages 4-5http://prof-80.fr/images/Carte_M2_M12_M16/Cartes_Floppy/8709198/Model_II_Revised_Floppy_Disk_Controller.pdf

author: RichardM
author_rank: Frequent Contributor
timestamp: January 09, 2021, 06:00:34 am
content: Thankyou
Any Idea what type of display is it?? - Page 1
Forum section: electronics / beginners

author: polarKaung
author_rank: Contributor
timestamp: July 21, 2022, 02:25:21 pm
content: Hi,I was poking around a clamp meter Chint NT-600A and found this type of display. Any idea what type of display is it?? How does the meter send data to it. I only saw two wires connected to it.

author: tunk
author_rank: Super Contributor
timestamp: July 21, 2022, 02:30:43 pm
content: LCD + zebra strip:https://en.wikipedia.org/wiki/Elastomeric_connector

author: oPossum
author_rank: Super Contributor
timestamp: July 21, 2022, 02:35:15 pm
content: The two wires are for the backlight. The LCD itself uses only the Zebra strip.

author: polarKaung
author_rank: Contributor
timestamp: July 21, 2022, 03:01:21 pm
content: Oh, the rubber thing. I thought it is just for support and i disconnected it to take the display out. How can I fix it?

author: tunk
author_rank: Super Contributor
timestamp: July 21, 2022, 03:08:59 pm
content: Put it back in the same position - most likely it will work.

author: polarKaung
author_rank: Contributor
timestamp: July 21, 2022, 03:11:58 pm
content: ok
Any ideas about the type of chip ? - Page 1
Forum section: electronics / beginners

author: NickGreece2025
author_rank: Newbie
timestamp: April 03, 2025, 08:52:04 pm
content: Hello to all eevbloggers!I am trying to repair a high frequency neurostimulation device, which is having a blown chip in the input circuitry. It is a portable device with 2 LiFePo (3.2V x2) batteries which operates only with batteries, in other words the power supply only charges the batteries (the device does not operate when the external power supply of 9V is connected, this is how it has been designed).The input circuit is actually a battery charger, based on a 10pin SMD chip (whish is blown in my case due to battery failure). A picture (of a new identical device) and a simplified schematic is attached.Any idea what that chip may be, where i could find it, or any ideas on how to approach it?Thank you all in advance

author: Andy Watson
author_rank: Super Contributor
timestamp: April 03, 2025, 09:04:33 pm
content: MCP73223-C2SI/MFhttps://ww1.microchip.com/downloads/en/DeviceDoc/22191E.pdf

author: NickGreece2025
author_rank: Newbie
timestamp: April 03, 2025, 09:18:10 pm
content: Thank you so much Andy Watson, I appreciate it.
Help newbie out. - Page 1
Forum section: electronics / beginners

author: Seaofdep
author_rank: Regular Contributor
timestamp: July 02, 2017, 05:20:10 pm
content: i found this and thought it was cool looking and newish lol so i believe its from a tv or monitor of some sort , it has genesis display perfection gm5321, smsc usb20h04-jd,(which I believe can be set to serial to usb ) i was wondering if its possible to modify it to a breakout/ converter board or any projects/ideas with it ? pointing me in the right direction will be very much appreciated , thank you.
Any ideas what component this is or could be - Page 1
Forum section: electronics / beginners

author: mikec
author_rank: Contributor
timestamp: May 26, 2013, 07:45:20 pm
content: Hi,Attached is a picture for a component that I can't find a datasheet for. The only print on it is R2E but searching for this doesn't bring up anything that makes sense. All I know is that it is 5 pin and has the R2E mark on it.

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 26, 2013, 11:14:15 pm
content: That's not R2C?

author: Fraser
author_rank: Super Contributor
timestamp: May 26, 2013, 11:25:10 pm
content: Always take a picture of such components at an angle and using a flash to show the laser etched writing. Straight down pictures give poor contrast.It helps to know the function of the PCB and to see the area around the component so that interaction can be assessed. this can sometimes lead to an ID on the type of component, followed by an exact match to the part no.

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 26, 2013, 11:42:43 pm
content: Seems to be a voltage regulator. Upper left pin in picture is probably V out.

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 26, 2013, 11:44:26 pm
content: Is this a battery powered board?

author: Stonent
author_rank: Super Contributor
timestamp: May 27, 2013, 06:03:31 am
content: Show us a pic with more of the board in it and give us an idea of what the board does. That may help.At least we could see for instance one pin going to ground it may help in the identity.

author: Unknown
author_rank: Unknown
timestamp: May 27, 2013, 06:29:51 am
content: I think it might be an LM4040.http://www.diodes.com/datasheets/LM4040.pdf.Marked "R2C" in the SC70-5 package.

author: amyk
author_rank: Super Contributor
timestamp: May 27, 2013, 06:36:21 am
content: Quote from: duskglow on May 27, 2013, 06:29:51 amAnd R2E is also an LM4040, but a higher tolerance range:http://www.ti.com/lit/ds/symlink/lm4040-n.pdf

author: Unknown
author_rank: Unknown
timestamp: May 27, 2013, 06:40:21 am
content: Good catch. There ya go. I'd be surprised if it wasn't an LM4040 at this point.It would still be helpful for you to post a larger picture of the board and a better picture of the device just to be sure.

author: mikec
author_rank: Contributor
timestamp: May 27, 2013, 07:35:48 pm
content: I think you guys have sussed it, I had at first thought it was a voltage reference but my searches kept taking me to some smd reed switch.It is connected to one end of the a trimming pot for setting the Vout of a PSU which I can see now is the providing the stable voltage reference.Cheers!
Any ideas? - Page 1
Forum section: electronics / beginners

author: rodrigopires
author_rank: Regular Contributor
timestamp: August 26, 2015, 12:28:13 am
content: Hi, i found a Motorola MC68705P3S in my chip box, and after some research i found out its quaite a good chip, and i wonder if thers any thing i can do with it? Some small project.Thanks!

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 26, 2015, 12:44:56 am
content: That's a lovely chip for yet another retro nixie clock. It would be about right because UV erase windows are not popular nowdays. They're from yesteryear. Oh I remember them well. I tried leaving a 2732 out in the sun for days to see if there was enough UV to effect it, there wasn't.It can do more than run a clock, but with only 1k, not too much.

author: rodrigopires
author_rank: Regular Contributor
timestamp: August 26, 2015, 06:11:02 pm
content: Hi a clock looks like a great idea! i think i can even use this vacuum bubble display that was on the same machine as the chip! It would look great! but i think that it's a little hard project, no?

author: Gyro
author_rank: Super Contributor
timestamp: August 26, 2015, 06:31:38 pm
content: I designed the control system for a manpack radio with one of those back in the 80's. Yes it was a good chip! Think it can probably handle a Nixie clock ok

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 26, 2015, 06:37:08 pm
content: yes, I would say you've got all the parts there to run the vacuum display. stands to reason you could do it and / or get a lot of experience and enjoyment seeing what you can do with it.

author: rodrigopires
author_rank: Regular Contributor
timestamp: August 26, 2015, 06:43:22 pm
content: Can i use a Nixie clock schematics with my display?

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 26, 2015, 06:46:08 pm
content: Quote from: rodrigopires on August 26, 2015, 06:43:22 pmhave a look at other schematics for similar displays, google image search for vacuum display driver circuits and click on something that is a similar type of display, doesn't need to be the same, and pick something with wires hanging off it, or a do it yourself circuit board. add DIY to the search.... then see what circuits are needed for a similar display
any input about the discontinued amprobe am-105trms - Page 1
Forum section: electronics / beginners

author: doctorm
author_rank: Regular Contributor
timestamp: June 27, 2010, 05:06:36 am
content: i found some for sale and was wondering if anybody knew if they were any good and/or knew anything about them besides the obvious specs that are given on the website spec sheet.its about the price of the am-220 that was reviewed, but its a higher accurate meter than the 220 so im considering it...

author: EEVblog
author_rank: Unknown
timestamp: June 27, 2010, 09:32:32 am
content: Replaced by the 34XR according to TestEquipmentDepot. That meter is in the $100 shootout.Dave.
Any IPS-like LCD with 7-segment style? - Page 1
Forum section: electronics / beginners

author: hap2001
author_rank: Regular Contributor
timestamp: May 05, 2024, 01:13:47 pm
content: Hi, I'm just wondering, with todays tech, why watches/calculators/wall clocks still have bad view angle?They do vary from model to model, but no one is as perfect as IPS used in PC/TV...

author: Buriedcode
author_rank: Super Contributor
timestamp: May 06, 2024, 05:24:57 am
content: Mostly because they use TN LCD technology which is indeed old. IPS is mostly used in active matrix displays - TFT's, with high pixel density, not passive displays with a few segments.The exception to this ia VA - vertically aligned - displays, which is a similar kind of technology that allows much better viewing angles. I say exception because, I think only one company makes these and they are used on old character displays that use 0.5mm pixel grids (which is massive compard to modern TFTs/OLEDs). So it's kind of an odd mix of old and new.Interstingly, VA dispalys seem to be even better than IPS, but for viewing angle and contrast, its the only technology I've seen applied to non-TFT passive dispalys. You may be able to find a seven segment VA display somewhere. The few 16x2 character VA displays I have have stupid viewing angles - at least 170 in both axis'.I just googled VA clock display and the first result...https://www.amazon.co.uk/Braun-Fast-Charging-Automatic-Backlight-Adjustment/dp/B09T3GWQV9surprised you didn't google it first
Any one heard of electro power supply? - Page 1
Forum section: electronics / beginners

author: asgard20032
author_rank: Regular Contributor
timestamp: June 14, 2016, 03:30:53 pm
content: My friend need to equip his lab, and while searching, I found that :http://i.ebayimg.com/00/s/NjAwWDgwMA==/z/kd4AAOSwVyRXTwmu/$_27.JPG35$ CADOriginally I wanted him to get some used HP power supply. But at this price... I am just wondering If anyone heard of those, can't identify that model.It is either 35$ CAD + some fuel and some wasted driving time or 60-80$ CAD for the top of the line used HP.Edit: Also found this one :http://i.ebayimg.com/00/s/NjAwWDgwMA==/z/~a0AAOSwintXS0t3/$_27.JPG for 25$, but again, know nothing about this one.

author: KMoffett
author_rank: Regular Contributor
timestamp: June 15, 2016, 04:02:15 pm
content: No images in your links!Ken

author: dentaku
author_rank: Frequent Contributor
timestamp: June 15, 2016, 08:00:21 pm
content: Quote from: KMoffett on June 15, 2016, 04:02:15 pmYou have to copy and paste the links into our browser because the URLs contain a $ which messes up the link on this forum.

author: wraper
author_rank: Unknown
timestamp: June 15, 2016, 08:14:30 pm
content: There is no current regulation on both of them.

author: macboy
author_rank: Super Contributor
timestamp: June 16, 2016, 03:05:40 pm
content: The Electro one is called a "filtered DC supply", which might mean that it is not even regulated. It might be little more than a variac followed by a rectifier and smoothing caps. The other one is intended for powering car electronics, such as a CB radio or something similar.Both of those are high current supplies. The first (Electro) looks like it might do up to 30 A, judging only by the meter. The second can do up to 12 A. Neither appears to have current regulation of any kind much less adjustable. That means that they could deliver far more than rated current in a fault (short circuit) condition. Using a high current supply for bench work is dangerous since an "oopsie" moment can cook your circuit and/or breadboards, and might even start a fire. I'd strongly recommend a lower current supply.
Any practical use for 1:1 high power choke, removed from HID lamp ballast? - Page 1
Forum section: electronics / beginners

author: LinuxHata
author_rank: Frequent Contributor
timestamp: May 26, 2022, 06:14:38 pm
content: Hello.I have several of these chokes, removed from the various DLP projector ballasts for UHP lamp (Osram P-VIP, Philips TOP C UHP).These are average sized (approximately 30x30x20mm) dual coil chokes, wound with litz wire and with non-magnetic spacing inside (had to took several of them apart). Inductance varies with model, but is usually in 50-90uH range. (top right on the attached picture).Since these have non-magnetic spacing, they should be usable for flyback converters, but 1:1 turns ratio limits that quite much. I tried to take it apart to reduce amount of wires on either side, but failed, they're glued too tightly. Another use is for SEPIC converter, maybe?I also considered use for an isolated DC-DC converter, but haven't found any practical circuit, which will take advantage of high power of this inductor.So any ideas for practical use of these chokes? I have about 30 of them lying around, so want to give some use to them.

author: jonpaul
author_rank: Super Contributor
timestamp: May 26, 2022, 06:19:52 pm
content: Trace schematic....probably not CM choke but a full bridge output inductor, sections to minimize self capacitance.either use as intended for series inductor on similar wattage resonant mode SMPS, or disassemble, salvage cores and bobbins and rewind as desired.Perhaps not worth the trouble, as gap cannot be changed.JonPS...."Nonmagnetic spacing" is called a gap!

author: LinuxHata
author_rank: Frequent Contributor
timestamp: May 26, 2022, 06:23:44 pm
content: Some are dipped into varnish, some are "bare", that depends on model. But I was not able to take neither of them apart - core always breaks on force, no matter what amount of solvent or heating I've used. So any use means use as is.
Any practical use for DLP projector APFC and ballast boards? - Page 1
Forum section: electronics / beginners

author: LinuxHata
author_rank: Frequent Contributor
timestamp: May 21, 2023, 04:44:27 pm
content: I've got large carton box full of APFC and ballast boards from various projectors. About 50-60 pcs. total. Most are Optoma, but there are few from LG and ViewSonic projectors. All these are from the dated models from 2006-2012 years, so no resale value at all.I try to find some use for them, apart salvaging the components. But to find some use, there's a need in understanding how it works, right?HID lamp ballast is relatively simple, since they quite closely match the circuit given in ballast driver IC datasheet. However, APFC board is much "harder", because it considerably differs from the schematics given in APFC controller datasheet:Besides the "normal" circuit, shown in datasheet, There is a thyristor or MOSFET, which appears to control either APFC output to ballast board or provide soft-start. Also, there is an another thyristor, which short circuits output of auxilary 12V power supply (based on TOP244 IC) in case of overvoltage. There also are a whole bunch of transistors, resistors and diodes/capacitors, which appear to implement some kind of protection or maybe mode switching for APFC chip (ICE1PCS02).I have an idea - to create a high voltage output, CC/CV capable power supply for testing long led strips. For this, I plan to run APFC module from an isolation transformer, which will provide about 12-24VAC, which will be used as input for this board.I did some experiments - removed UVLO from APFC chip and supplied VCC to it via the external power supply and it worked- 390V was delivered at output.So there are two main questions:1. Maybe anyone has the circuit diagram for the projector APFC board (I found one online, but it is very very old, not closely matching any boards I do have)2. Are there any other interesting uses for these boards?

author: barshatriplee
author_rank: Regular Contributor
timestamp: May 23, 2023, 02:45:52 pm
content: Salvaged APFC boards can be used for educational purposes or demonstrations. You can use them to showcase the principles of power factor correction, high-voltage power supply design, and LED lighting systems. This can be particularly useful for teaching electronics or conducting workshops. Here is also a troubleshooting video:
Any reccomendations for common waterproof gpio and can connectors? - Page 1
Forum section: electronics / beginners

author: boguesuser
author_rank: Newbie
timestamp: January 06, 2025, 07:11:58 pm
content: I was previously using jst ph connectors for can fd and a 2x06 P1.27mm horizontal connector for GPIO but I want to move to waterproof my enclosure.Any recommendations for a waterproof 3 pin and a 12 pin connector that I can add to a pcb?

author: tinymini
author_rank: Contributor
timestamp: January 07, 2025, 12:28:31 pm
content: If you need really rugged and easy to fiddle connectors, I'll go with waterproof ethernet panel mount connectors, and aviation connectors (the round screw-lock ones).But they're bloody expensive, so for hobbies I'll use either waterproof cable glands and / or automotive connectors.https://prd.sws.co.jp/components/series/pdf/jp/2404_components_je.pdfYou can find sets of them on amazon - just maybe not for 12pin.Also, check your cable ratings for outdoor use if you're using outdoors. UV light likes to destroy practically everything.If you're feeling really lucky and wat to try PCB mounted ones, repurposing IP68 USB-C connectors might work too - although the cable won't be waterproof.

author: squadchannel
author_rank: Frequent Contributor
timestamp: January 07, 2025, 12:55:35 pm
content: JST JWPF / WPJhttps://www.jst-mfg.com/product/index.php?series=397https://www.jst-mfg.com/product/index.php?series=151best connector.hmmm 12 pin is too much.Amphenol Sine AT / ATP / ATM ?https://www.amphenol-sine.com/at-serieshttps://www.amphenol-sine.com/atp-serieshttps://www.amphenol-sine.com/atm-seriesTE Deutsch DT / DTP / DTM?https://www.te.com/en/products/connectors/automotive-connectors/intersection/deutsch-dt-series-connectors.html?tab=pgp-storyhttps://www.te.com/en/products/connectors/automotive-connectors/intersection/deutsch-dtp-connectors.html?tab=pgp-storyhttps://www.te.com/en/products/connectors/automotive-connectors/intersection/deutsch-dtm-connectors.html?tab=pgp-story

author: boguesuser
author_rank: Newbie
timestamp: January 07, 2025, 06:55:19 pm
content: I'll look into all these. They seem a bit on the large side at first glance but I might be able to work with that.
Any resource to understand the basic feedback operation in electronics? - Page 1
Forum section: electronics / beginners

author: mohannad
author_rank: Contributor
timestamp: March 01, 2017, 12:29:08 pm
content: I have a basic understanding of the concept of feedback and the control theory in general, but i was going through "art of electronics"and i really liked the introduction of the concept of feedback but transistor circuits looks very tricky.when dealing with feedback using op amp it's quite easier but when it comes to transistor things get complicated.Any recommendation on this specific concept? any recommended resources?

author: LvW
author_rank: Frequent Contributor
timestamp: March 01, 2017, 06:45:35 pm
content: Quote from: mohannad on March 01, 2017, 12:29:08 pmFor a single transistor stage, there are in principle only two (negative) feedback alternatives:(1) With respect to the collector output, the base is an inverting input. Therefore, we can apply the basic feedback principle known from the opamp feedback scheme: (a) A resistor RB between collector C and the base node B or (b) a voltage divider between C and ground (midpoint at B)..Here it is possible to directly observe the feedback loop.(2) In contrast, using a feedback resistor RE (emitter path), the feedback loop cannot be visually identified. However, using the small-signal parameter gm (transconductance) we can find an equivalent diagram which clearly shows the feedback loop (see attached jpg file):In this simplified diagram I have used the assumption IE=IC (a somewhat extended diagram including the base current IB can be easily found).
Any school regrets or "wish I would have"? - Page 1
Forum section: electronics / beginners

author: RickieSalad
author_rank: Regular Contributor
timestamp: July 07, 2014, 10:04:28 am
content: For all of the official EE's out there. Is there anything you'd do differently if you had to go back and do your EE degree over again? Maybe classes you didn't pay enough attention to?

author: KJDS
author_rank: Super Contributor
timestamp: July 07, 2014, 11:14:55 am
content: I'd have spent a little more time rock climbing and a little less drinking.

author: Leestons
author_rank: Contributor
timestamp: July 07, 2014, 11:22:18 am
content: I wish I took electronics at school instead of product design.

author: con-f-use
author_rank: Unknown
timestamp: July 07, 2014, 12:32:29 pm
content: Not an EE but I'd have taken Spanish classes while I could and had the extra time. My university was offering them for free.

author: katzohki
author_rank: Frequent Contributor
timestamp: July 07, 2014, 04:23:31 pm
content: Actually, I wish I had spent more time socializing! By the time I really came out of my shell and started going to extracurricular activities I was already really busy.Aside from that, I wish I had spent more time with robotics, but that is just because of where I ended up in my first job.

author: Dongulus
author_rank: Regular Contributor
timestamp: July 07, 2014, 05:28:11 pm
content: I wish I had forced myself to spend more time on campus rather than going back home as often as I did. I would have given myself less grief if I treated school like a 9-5 job. I could have gotten more work done while on campus which would have given me more time for socializing, fun, and sleep.I also wish I had chosen something more substantial for my senior project. I basically threw together some things I was interested in working on into one system, purely for the sake of learning and with no real concept guiding the project. The result wasn't really impressive, nor did it solve any problem. I certainly learned a lot from my senior project, but I would rather have had a project worth showing off to people, or a product with which I could potentially have started an enterprise.
Any such thing as a BEC SOT223 NPN transistor? - Page 1
Forum section: electronics / beginners

author: mayor
author_rank: Regular Contributor
timestamp: March 09, 2015, 01:31:32 am
content: I ordered a few boards before I noticed that the editor I am using assigned a strange order (BEC instead of the common BCE) for a SOT223 NPN transistor.Does anyone know of a part # with this configuration? Specs can be pretty loose, very low current and fairly low voltage (<=16V), just about any frequency will do.TIA

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 09, 2015, 03:15:06 am
content: Why is it SOT223 (a power device) if it can be rated very lightly?You should be able to bend the leads of a 2N3904 or similar part onto pads that size, very easily.Tim

author: mayor
author_rank: Regular Contributor
timestamp: March 09, 2015, 11:04:00 am
content: Hi Tim,it's what I had on hand :-) I am sure I can find a TO92 and bend it like you suggest, thanks!
Any switching controller with built-in booster for mosfet gate driving? - Page 1
Forum section: electronics / beginners

author: LinuxHata
author_rank: Frequent Contributor
timestamp: May 29, 2024, 04:51:34 am
content: Hello. I'm making a flyback converter, which delivers up to 20W into load at 200-400V voltages. power supply is 3-5 volts.I have to use high voltage mosfets, like IXTQ82N25P (yes I know this is an overkill, but I have a lot of them in stock), which require strong and high voltage gate driver (no logic level hv mosfets are available for CHEAP).So far, I'm making them in the following way - SX1308 boosts input voltage to 15V, from which, UC3843 is operating and driving mosfet.Everything works fine and efficiency is quite good. However, I'm curious, whenever there's an integrated solution (controller+booster), which can internally boost low input voltage to drive high voltage gate mosfets? I was not to able to find any...Thanks in advance.

author: Berni
author_rank: Super Contributor
timestamp: May 29, 2024, 05:17:20 am
content: That's not all that common functionality for dc/dc controller chips.But they do often have a pin that supplies power to the internal gate driver. So you can use a small boost dc/dc chip to generate the 15V and feed that to the controller chip to use as gate drive.But if you have a particularly hard to drive MOSFET with a crap ton of gate capacitance, then you might want to be using a separate gate driver chip anyway to get a >5A gate drive current or something.
Need help with thermography - Page 1
Forum section: electronics / beginners

author: Oslaw
author_rank: Contributor
timestamp: April 15, 2019, 01:12:50 pm
content: Hello, I am new to thermography. How do you make simple and advance analysis and generate report ?Thank you for your answer.

author: Gyro
author_rank: Super Contributor
timestamp: April 15, 2019, 07:26:29 pm
content: I think you need to be looking in the Thermal Imaging section - you should be able to relocate (not duplicate) your post there. [Edit: If you need to - there are lots of links to useful guides there.]https://www.eevblog.com/forum/thermal-imaging/free-thermography-and-camera-use-guides-books-the-list-)/

author: Oslaw
author_rank: Contributor
timestamp: April 15, 2019, 10:05:31 pm
content: Thank you very much.
Any tips for getting started with Arduino & LCD touchscreens? - Page 1
Forum section: electronics / beginners

author: v81
author_rank: Regular Contributor
timestamp: November 13, 2016, 06:19:59 am
content: I have a little Arduino experience and am looking to move toward including lcd touch for display output and user input.There are a number of methods of interfacing and i'm not sure where to start.Wondering if anyone out there might be able to make a suggestion based on my experience and needs.Looking to use minimal connections between display and arduino if possible.Lots of what i've seen like to use the 18pin header in an Arduino Mega.Are there any alternatives i could drive from a smaller pin count arduino?Are there any disadvantages in skimping on the interface (cost/performance?)Here is a site where i have an eye on a number of choices.http://www.icstation.com/tft-lcd-c-329_332.htmlHave also been looking at smaller OLED displays...http://www.icstation.com/oled-c-329_333.html0.96" Inch I2C IIC Serial 128X64 Blue OLED0.96" Inch I2C IIC SPI Serial 128X64 Blue OLEDNot sure weather i should go SPI or not.Any suggestions there?Look forward to replies, thanks for your time ladies and gents.

author: JacquesBBB
author_rank: Frequent Contributor
timestamp: November 13, 2016, 06:51:02 am
content: You can have a look to nextion displayshttps://www.itead.cc/wiki/Nextion_HMI_Solution

author: VladimirM
author_rank: Newbie
timestamp: June 01, 2017, 05:58:19 pm
content: I agree nextion displays are very easy to work with. It is basically just sending ASCII strings to uars and receive them back.For start you can even use RS232 terminal to test this protocol and basically finish display program even without external microcontroller.Here is short tutorial i made about this:http://www.electronics-base.com/featured-components/display/nextion-display-and-docklight-adding-gui-to-your-microcontroller-projectsJust basic example, but that is exactly what you need at this stage.
Any tips for reverse engineering connectors? - Page 1
Forum section: electronics / beginners

author: rthorntn
author_rank: Frequent Contributor
timestamp: June 14, 2021, 05:46:33 am
content: Hi,I have two old Sun X4540's (Thor).I like the "mainly passive" disk backplane, frame and caddies, I want to try to use it for modern disks (the X4540 I/O board has SAS1 LSI HBAs that only support 32-bit LBA for SATA, so 2.2TB).I was thinking I could reverse engineer the connectors and have a PCB made that connected to the backplane and the PCB would have twelve modern SFF and molex power connectors on there, I would just connect it to a modern motherboard, HBA'a and PSU.When I say "mainly passive" the board has some ICs, the two bigs ones are Maxim VSC055's (2-wire Serial Backplane Controllers).The backplane uses five SATA connectors for fans and has two USB ports (w/ CY7C65640A USB hub controller), none of that is required.So I want to keep one X4540 intact but I can desolder stuff like connectors from the other.The service manual has the pinouts for both "data" connectors (Molex 75019-0020) but something seems funky:https://docs.oracle.com/cd/E19121-01/sf.x4500/819-4359-19/appd-pinouts.html#50647087_42729The X4540 only has one table in the manual (D-9, J24 to J49), either I'm missing something or the second table is missing.You might think, maybe use the X4500 D-8 table for the X4540 but if you do it doesn't make sense, doing a browser "find" for DISK40 at the above URL it finds 8 entries, 5 under the X4500 section and 3 under the X4540, you want 5 pins per disk (TX pair, RX pair and Activity LED), the X4540 table only has the RX pair and the Activity LED.So I thought maybe the DISK40 TX pair are at the same position as the RX pair but on the second connector?I've tried doing some simple DMM continuity checks on the backplane (between the SATA data and 75019-0020's) but it seems futile, is there another way?I guess I could also look at having a "simpler" backplane produced, with SAS connectors perhaps, its 530 x 410mm and so would probably cost like USD$250.Anyway I would really appreciate any advice.Thanks.Richard
Any way to make a Zigbee module work with capacitative touch switch? - Page 1
Forum section: electronics / beginners

author: elcrni
author_rank: Regular Contributor
timestamp: October 05, 2023, 07:27:19 am
content: hi all,So in a process of retrofitting some of my apartment switches to Zigbee and Home Assistant. Tested some 10 different modules and switches so far, settled with high quality NodON zigbee modules.Now in a process of finding nice switches, first option is to just retrofit to rocker switches i already have and the second option, IF possible, Livolo touch switches.I really like their line of switches and outlets but they sadly dont work with zigbee modules as need some sort of load to work. I am aware Livolo have zigbee line of switches but those are pure junk.So my question here is, any safe way of making touch switches to work with a Zigbee module?Many thanks in advance,Alek
Any way to throttle the currents in an alarm's bell-box circuit? - Page 1
Forum section: electronics / beginners

author: MJK
author_rank: Newbie
timestamp: May 27, 2020, 02:43:14 pm
content: Newbie (electronically!) here – though I've been watching some of Dave's videos for years – but had never thought of looking up EevBlog! And, superb discussions here, and great help, and great atmosphere – thanks to you all!I've searched here, and on many other sites, and I've looked at hundreds of LM317 schematics, op-amps, etc, etc, without getting anything that, I think, matches my needs – so maybe what I'm seeking is impossible, or so simple that nobody has bothered to address it! (Personally, I studied VALVEs a little, over 50 years ago, but have done very little electronics since then).Standard home alarm, maybe 30-35 years old, with an external “bell box” – containing a 12V siren and 12V strobe light. That circuit (quite thin cable) is about 50 feet long, and has a loud internal buzzer, and the 12V supply, at the other end. The old strobe light had a small PCB, with about 15 components (resistors, diodes, small trafo, caps – and one large item, maybe a cap, marked “630V, 7-Stars”! There's a glass/neon-type light on it – I've no idea what it's called; schematic and/or photos available, if useful. That light no longer works – perhaps the “light” itself is shot.So, I got a standard LED-based strobe, with about 25 LEDs. The light flashes at about two-per-second. I've watched the current usage of the strobe light – it's interesting – it goes to about 120mA for about 2 seconds, then drops to about 5mA for another 5 seconds, and repeats that cycle.However, when wired up, the new strobe does not work well! When the 12V is applied, at most, it might emit a few weak flashes, and no more.My guess is that the the 12V supply is inadequate to drive the local buzzer, the long, thin cable, the old siren, and the new strobe. I'm guessing that the supply might drive 600-700mA, and that the buzzer takes about 150mA, the siren about 350-450mA, and the strobe 120mA.So, I wonder if there's any component/circuit available that I could install (and adjust) at the feeds to the three loads, to throttle (restrict, balance, limit?) the currents going into them? Obviously, the new circuit(s) would need to use very little current – maybe a few mA each – and drop the voltages only minimally also – maybe 1-1.5V max?If nothing is available, I guess I should search for a strobe that needs less current, or a new box, with integrated siren and strobe, and, hopefully, a max load of about 300-400mA.Many thanks for any advice, or links, that you might have. Michael.
Any way to visually identify a proper anti static bag sold on eBay? - Page 1
Forum section: electronics / beginners

author: Decoman
author_rank: Regular Contributor
timestamp: December 27, 2017, 02:50:37 pm
content: I thought it would be good idea to stock up on some anti static bags of various sizes, and as I normally buy stuff off eBay I am inclined to just get it there, though I realize that having learned that there are different types of bags that wholly or in part fulfill ones need to protect some components inside a bag, I am bewildered when seeing photos of such products on eBay.So I would like to know, is there any way to recognize a proper anti-static bag in a photo when making a purchase anywhere on the internet?Is there a way to be able to pick a non conductive bag by just making a visual judgment off the product photo/illustration?Afaik, there are various types, where some are made to not build up a charge, but does not prevent a component inside from getting damaged when coming into contact with an exterior source of electronic charge (like, your hands for example).I think I've seen anti static bags for my computer hardware stuff that looks like a half transparent bag gone plaid, with this criss cross pattern to it, making me naively think that the type of bags I had would provide all the ESD protection one would want.Note; I have previously watched this one EEVblog video about the subject of anti-static bags.Edit: I am suddenly in doubt if I perhaps is misusing the term 'anti-static bag', and maybe an 'anti-static bag' is per terminology not supposed to be really ESD/electro static discharge safe. I guess perhaps there could be bags terms as being "ESD safe", but maybe I am wrong in thinking that.

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: December 30, 2017, 12:47:40 am
content: Antistatic comes in 2 types:Conductive...to conduct away any charge; andNon conductive, made with materials not to generate or minimise a charge.The Conductive stuff has criss-cross patterns of conductors around it, generally some sort of carbon material. Sometimes you see antistatic tape like this. They work well.The non conductive, slightly looking metallic sheen to them, like the computer bags.I buy mine from RS components but being in EU you should be able to but from them or Element14 cheap enough. Yes as for Chinese fleabay stuff...yeah they'd fake anything so I buy from reputable sources. Each has its purpose. Hope this helps.edit:Oh forgot...carbon impregnated bags...that look dull black! But best to buy from a reputable source for any bags.
anybody get questioned by customs clearance for buying capacitors? - Page 1
Forum section: electronics / beginners

author: 3roomlab
author_rank: Frequent Contributor
timestamp: November 10, 2015, 10:30:12 am
content: well i did ...

author: alanb
author_rank: Frequent Contributor
timestamp: November 10, 2015, 10:46:42 am
content: They probably thought that they were Flux Capacitors.

author: Xenon Photon
author_rank: Unknown
timestamp: November 10, 2015, 11:06:44 am
content: That always happens here but they do it to get extra money from the importer by increasing the time it is stored at customs (the importer pays for each day his good is filling an area at customs).Although this is only applicable to huge goods not some capacitors and not at the exported country!

author: nuno
author_rank: Frequent Contributor
timestamp: November 11, 2015, 12:09:04 am
content: It depends on what's their Farad and Voltage specs and if they come charged or not.

author: 3roomlab
author_rank: Frequent Contributor
timestamp: November 11, 2015, 04:27:01 am
content: Quote from: Xenon Photon on November 10, 2015, 11:06:44 amyea strange isnt it? caps becoming an item of scrutiny

author: ivanjh
author_rank: Unknown
timestamp: November 11, 2015, 05:15:10 am
content: It's just overly zealous.Security Export Control System in Japan - "Catch-all Control: Exporters have to apply for an export license in cases where the item or technology is not on the control lists but could conceivably contribute to WMD proliferation programs." -http://www.meti.go.jp/policy/anpo/englishpage/overview.pdfI can conceive of a WMD proliferation program based upon duct tape & crazy glue...

author: Psi
author_rank: Super Contributor
timestamp: November 11, 2015, 05:42:12 am
content: You have to answer an intended use question every time you order something from digikey if you are outside the USA.

author: SpidersWeb
author_rank: Unknown
timestamp: November 11, 2015, 06:22:40 am
content: Such a pointless step, like a terrorist is really going to write "Bomb Manufacture"Who makes these rules :/

author: Neilm
author_rank: Super Contributor
timestamp: November 11, 2015, 06:48:19 pm
content: Quote from: SpidersWeb on November 11, 2015, 06:22:40 amEven funnier if you are working on prototype military equipment. Hence I used to put statements along the lines of "prototype servo system" - didn't use the phrase gun control equipment at any time. They didn't spot it

author: Seekonk
author_rank: Super Contributor
timestamp: November 11, 2015, 07:06:48 pm
content: I remember trying to get on a plane with a carry on bag filled with a couple hundred yellow film 1uF capacitors. This was back before you couldn't joke about a bomb. The checker asked what these were. I said they were capacitors. She said, If you hold one of these up and ask for $50,000 are we supposed to ask what they are. I said, For $50,000, I would. Another inspector said, He's one of those (insert company here) guys and told her to let me go through.
anybody know a good power feedback resistor calculator? - Page 1
Forum section: electronics / beginners

author: navidrct
author_rank: Regular Contributor
timestamp: August 07, 2017, 05:17:39 am
content: hianybody new good power feedback resistor calculator?

author: danadak
author_rank: Super Contributor
timestamp: August 07, 2017, 10:05:43 am
content: Can you expand on your question, maybe post a simple schematic. Questionnot quite detailed enough to help you.Regards, Dana.

author: navidrct
author_rank: Regular Contributor
timestamp: August 07, 2017, 11:25:17 am
content: Quote from: danadak on August 07, 2017, 10:05:43 amMOST of PSU IC like tps54331 and lm117 has feedback resistor that determines its output voltage. there is an equation in their datasheet but if there was a calculator that calculates its feedback resistor considering standard resistor would be nice and fast to change themdo u know any offline calculator that do that ?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 07, 2017, 04:52:36 pm
content: Oh, resistor divider calculator and resistor selector? Yes:http://jansson.us/resistors.htmlTim

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2017, 05:33:24 pm
content: Here's a link to my favourite calculator site. It also has other useful maths tools.http://sim.okawa-denshi.jp/en/

author: navidrct
author_rank: Regular Contributor
timestamp: August 08, 2017, 08:57:47 am
content: Quote from: T3sl4co1l on August 07, 2017, 04:52:36 pmthat wasn't the casesomething like this but offline and wrote in c#http://www.changpuak.ch/electronics/FeedbackCalculator.php

author: BradC
author_rank: Super Contributor
timestamp: August 08, 2017, 09:00:41 am
content: 10 seconds with a spreadsheet, or a pocket calculator and bit of paper.

author: navidrct
author_rank: Regular Contributor
timestamp: August 08, 2017, 09:01:01 am
content: Quote from: Hero999 on August 07, 2017, 05:33:24 pmplease see thisi need something like thishttp://www.changpuak.ch/electronics/FeedbackCalculator.phpbut offline

author: navidrct
author_rank: Regular Contributor
timestamp: August 08, 2017, 09:04:51 am
content: Quote from: BradC on August 08, 2017, 09:00:41 amu should calculate resistors and then look up on ur local supplier if they have that standard or notso calc that consider the standards resistor and choose the resistor according to them would be a fast jobtill now im using windows calc and have no problem but I think it would be nice if I find that software

author: matseng
author_rank: Frequent Contributor
timestamp: August 08, 2017, 09:38:38 am
content: It was easy enough to strip out all "unnecessary" code from that site and make a small html that can be opened in most browsers by just double-clicking the file.Save the attachment to your computer and change the extension from .txt to .html (html files can't be uploaded here)It looks a bit plain since I removed all styling, but it's kinda ok anyways I think ;-)

author: navidrct
author_rank: Regular Contributor
timestamp: August 09, 2017, 05:09:39 am
content: Quote from: matseng on August 08, 2017, 09:38:38 amthanks allot that was helpful