hybridfree/eevblog-posts huggingface dataset:
Will this Ni-MH Charger circuit work? - Page 1
Forum section: electronics / beginners

author: Reider
author_rank: Contributor
timestamp: December 20, 2016, 08:59:06 pm
content: HelloI'm designing an Arduino powered device with an Ni-MH battery and charger.Also I have an adjustable constant voltage, constant current board I want to use with a C/4 output current.The micro would pulse charge the battery switching on and off the change voltage once a few seconds and when off measuring the cell voltage and temperature to detect dT/dt and -dV/dt.I also don't really want to use a heat sink on the 7580 so I would just use it for logical stuff and using the internal regulator for the Arduino.The battery is a 12 cell 14.4V Ni-MH battery pack so I would set the charge voltage for about 1.4V/cell 17V + the diode forward voltage so 18VMy main concern is the logic level FET. I have a fixed supplier in mind and not a lot of logic level types are available.Thanks for any feedback, here are the datasheets:http://www.alldatasheet.com/datasheet-pdf/pdf/84033/IRF/IRLZ24N.htmlhttp://diotec.com/tl_files/diotec/files/pdf/datasheets/1n5400.pdf

author: amspire
author_rank: Super Contributor
timestamp: December 20, 2016, 10:00:15 pm
content: NiMH batteries are not the easiest to charge and a battery with 12 cells becomes harder. The dV/dt method will probably be useless because each cell will have a slightly different state of charge and the dT/dt method may need sensors on every cell.Not sure what the best method is for 12 cells - maybe to charge at c/4 till about 1.36V a cell (might get you to about 50%) and then drop down to 0.05C for 15 hours?The NiCd batteries were much easier in battery packs as the individual cells could withstand a lot of overcharge, and in my experience, many of the NiCd batteries were still working fine after 20 years. Otherwise, everyone is now looking for lithium battery solutions in new designs.Basically, it will be pretty hard to charge 12 NiMH cells to near 100% in 5 to 6 hours. If you can get to 95% in 24 hours without stressing individual cells, you have done very well.

author: Reider
author_rank: Contributor
timestamp: December 20, 2016, 10:18:00 pm
content: Hello yes I was not really clear on the battery. So they are in a 12 cell battery pack so they are always charged and discharged together. This should make them a little bit easier to handle. The pack also has a built in thermistor I will use to detect temperature. My main concern is the FET and did I do something stupidAlso you are right I may have to implement a slow charge too.
Will this PMIC do the trick? - Page 1
Forum section: electronics / beginners

author: Zinglish
author_rank: Newbie
timestamp: June 07, 2017, 04:45:07 pm
content: Project power requirement: 1V8 @ 250mA min and 3V3 @ 250mA min with a 3v6 battery and USB charging / powering (5V in) capabilities.Will this IC do the trick:http://www.linear.com/product/LTC3586-2? Also, would it better to split the work up amongst specialist ICs or is this single IC ok?

author: Buriedcode
author_rank: Super Contributor
timestamp: June 07, 2017, 11:30:11 pm
content: That looks ideal for your application, and if anything, overkill. But if you're just making one, then I'm sure it will do just fine - the extra boost output can be optional.

author: Zinglish
author_rank: Newbie
timestamp: June 08, 2017, 05:12:21 pm
content: Thanks for the awesome replies! I took at a look at the LP3923 chip (thanks for the great suggestion blueskull) and figured that the LDO currents are probably too low for what I need them for (250mA is minimum for my application and will likely rise to 700mA under heavy load). Is it possible to combine LDOs? I was doing a bit of research on the topic and there's a lot of no-nos around combining 2 separate PMIC LDOs but nothing on combining LDOs from the same PMIC.After hours of research I also managed to find this bad boy:http://www.ti.com/product/TPS65217which has 3 bucks @ 1.2A which again is overkill but I'd rather have the power available than have the device starve. It's still quite expensive ranging from $2.5 (batch) - $5 (single) but cheaper than the LT PMIC I mentioned and has plenty of power for the price. It also has a WLED driver and considering I am attaching a 4.3" TFT display this is quite a nifty feature. If I could find something very similar to this (I don't need the 3rd buck and perhaps only need 2 bucks / LDOs @ 1A) but cheaper it would be end game.
Will this relay work for my requirements? - Page 1
Forum section: electronics / beginners

author: redgear
author_rank: Frequent Contributor
timestamp: July 16, 2020, 06:00:48 pm
content: I am trying to drive a 6A reactive load(power factor 0.6, crest factor 1.85) using a DC relay. Either 12v or 5v.I found this relay ondigikey:DATASHEETWill this suit my requirements?Thanks

author: bob91343
author_rank: Super Contributor
timestamp: July 16, 2020, 07:30:25 pm
content: I don't see any reactive load specifications. So it's a crap shoot. Best to contact the relay manufacturer and ask.

author: cliffyk
author_rank: Frequent Contributor
timestamp: July 16, 2020, 09:19:23 pm
content: It's rated at 20 A for use with a 277 VAC lighting ballast--should be fine for your application:

author: floobydust
author_rank: Super Contributor
timestamp: July 16, 2020, 10:28:13 pm
content: OP is being a jerk, his 8-page cross-posted threadhttps://forum.allaboutcircuits.com/threads/critique-my-schematic.171272/page-8he says he needs a 4-pole relay

author: redgear
author_rank: Frequent Contributor
timestamp: July 17, 2020, 03:02:23 am
content: Quote from: cliffyk on July 16, 2020, 09:19:23 pmQuote from: bob91343 on July 16, 2020, 07:30:25 pmThanks.Quote from: floobydust on July 16, 2020, 10:28:13 pmI am looking for replacing the 4-pole relay as they are very expensive

author: cliffyk
author_rank: Frequent Contributor
timestamp: July 17, 2020, 03:25:48 am
content: Lighting ballasts are commonly reactive loads. Even those in the fluorescent lights in your garage...
Winbond W9825G6JH-6 upgrade for DIR-300 - Page 1
Forum section: electronics / beginners

author: u666sa
author_rank: Frequent Contributor
timestamp: December 08, 2023, 04:47:24 pm
content: I received today HY5DU121622CTP-D43 memory chip, and was happy, opened up my DIR-300 B7/NRU, unsoldered RAM, and was going to plug in this new chip, when I noticed pins don't alight. Turns out the new chip is 66pin TSOP II, original chip on board is Winbond W9825G6JH-6 TSOP II 54-pin. This sucks man.So I have two questions:1) The chip I have is TSOP II 54-pin, 400 mil, W9825G6JH-6, 166MHz/CL3 or 133MHz/CL2, 4,194,304 Words * 4 Banks * 16 Bits. Is that 32 megabytes of memory? Because in tech specs for my router, DIR-300 B7/NRU it lists it as 32 MB.https://openwrt.org/ru/toh/d-link/dir-300revb2) Can you please find me a chip in this same exact package that is 64 MB? It doesn't matter if it's not Winbond. So long as I can purchase it on aliexpress, because it's cheap and shipping is fast, the wrong one cost me $1.5 and got shipped in 16 days. Oh, and it should be compatible with my chip, direct replacement, only bigger size. 64 MB.
Winding direction of SMPS output filter inductors? - Page 1
Forum section: electronics / beginners

author: MathWizard
author_rank: Super Contributor
timestamp: July 08, 2021, 06:44:51 pm
content: I took apart another computer PSU to measure all the values I could with an LCR meter. But I forgot to check the winding direction for the various output filter inductors, which are un-coupled, single coil inductors. But there's currents going everywhere, magnetic fields going everywhere, so IDK if it matter's or not, if I put them back CW or CCW, relative to each other and any thing else. A couple are close together, but they are all close to other things, and traces and currents going everywhere.I haven't done near enough physics/math for SMPS analysis with magnetics, besides the most basic. I would assume just have both 12V rail inductors CW or CCW, same for the 2 on the 5Vstby rail, and the 2 on the -12V rail.

author: Benta
author_rank: Super Contributor
timestamp: July 08, 2021, 07:38:28 pm
content: Erm... a coil has the same winding direction, irrespective of whether they are turned 180 degrees. You know, like a screw thread. Reversing a screw's orientation doesn't change the thread.

author: MathWizard
author_rank: Super Contributor
timestamp: July 08, 2021, 09:32:43 pm
content: Ok good point, and it doesn't flip the z-axis mag field anyways, so just don't put them on the bottom side of the PCBNow I just need a machine to sort my backwards colored resistors
Winding your own Inductors - Page 1
Forum section: electronics / beginners

author: Bryan
author_rank: Frequent Contributor
timestamp: November 30, 2016, 06:30:03 am
content: Hello all:Is there a gauge of wire which is preferred for winding inductors. Is the gauge that important as long as you use the calculations in the many available calculators to determine the final inductance (assume current may be the biggest factor?). Any preferences? I find too fine a gauge tends to want to unwrap vs a thicker gauge.Cheers

author: coppice
author_rank: Super Contributor
timestamp: November 30, 2016, 06:49:57 am
content: The thickness of the copper in your inductor wire is about achieving an acceptable amount of resistance, and consequent power dissipation. The thickness of the insulation on the wire is about achieving the required insulation performance. If you need super thick wire, bendability may become an issue. If the only need extremely thin wire, breakage during winding may become an issue.

author: tron9000
author_rank: Frequent Contributor
timestamp: November 30, 2016, 09:03:55 am
content: I recently wound my own for a project. I found that superglue held the coil in place quite well on the core (iron nail)

author: madires
author_rank: Super Contributor
timestamp: November 30, 2016, 11:18:35 am
content: The most important point which determines the minimum wire gauge required is the current the inductor has to pass. Usually the cross section is about three times what you would select for a simple wire, because the wire is wound dense and in layers (-> heat dissipation). You can download some nice charts from a few web sites.

author: CJay
author_rank: Super Contributor
timestamp: November 30, 2016, 12:09:51 pm
content: Depends on frequency, skin effect, interwinding capacitance, spacing, wire plating, insulation type and many other factors including wire guage can all have an effect when you're dealing with high frequencies.So, it's not an easy question to answer unless you define what the inductor is going to be used for
Window Comparator Has Strange Outputs - Page 1
Forum section: electronics / beginners

author: Scr1bbl3
author_rank: Contributor
timestamp: April 28, 2023, 10:39:07 pm
content: Hi all,I found the circuit below in the interweb and deiced to build it for giggles. I am using a dual BA4560 ic with the voltage divider resistors 10K each at 5VCC. The pull-up resistor is 5.1K. The trip points should be 1.66V and 3.33VThe outputs below 1.66 and 3.33 read 3V, not zero. Between 1.66 and 3.33, I do measure 5V. Any ideas why the circuit doesn't go to zero?Thanks,Scrib

author: ataradov
author_rank: Super Contributor
timestamp: April 28, 2023, 11:44:58 pm
content: BA4560 is an opamp, not a comparator. And it actively drives the output (push/pull), while your circuit is designed for an open collector output.You get outputs of the opamps fighting each other. One tries to drive VCC one tries to drive GND, you get the middle voltage.While it is possible to use opamps as comparators in some cases, it is not going to work here.

author: gnif
author_rank: Unknown
timestamp: April 29, 2023, 12:49:18 am
content: Double posting is not permitted on these forums, please refrain from doing it again:https://www.eevblog.com/forum/beginners/window-comparator-has-strange-outputs/msg4837664/Locking thread.
Window Comparator Has Strange Outputs - Page 1
Forum section: electronics / beginners

author: Scr1bbl3
author_rank: Contributor
timestamp: April 28, 2023, 10:30:19 pm
content: Hi all,Found this windows comparator on the interweb and decided to implement it for giggles. Simple premise but it has some odd outputs. The voltage divider resistors are all 10K and the pullup is 5.1K so the trip points should be 1.66V and 3.33 volts with 5Vcc. I am using a BA4560P comparator (dual comparators)When I am below and above the trip points of 1.66 and 3.33, I get 3V at the output.Between 1.66 and 3.33, I get 5.Can anyone explain this?Thanks, Scrib

author: John B
author_rank: Frequent Contributor
timestamp: April 28, 2023, 10:37:15 pm
content: BA4560P is a an opamp, not a comparator. It will not be able to swing completely to the supply rails and a pullup resistor isn't doing anything useful in this situation.Try using a basic comparator like the LM393.

author: wasedadoc
author_rank: Super Contributor
timestamp: April 28, 2023, 10:42:33 pm
content: Your comparators are not "open collector". The 3 Volt output is when you have one pulling high and the other pulling low. A quick fix is to insert a diode on each comparator output before the pull up resistor. Cathode to comparator output. Anodes commoned and connected to pullup resistor. Or use open collector types such as suggested LM393.

author: Scr1bbl3
author_rank: Contributor
timestamp: April 28, 2023, 10:44:05 pm
content: Thanks John,I can't believe I did that. I just pulled the bag out of the drawer labeled comparator and just popped it in. Don't trust the labels and double check the part number.

author: Scr1bbl3
author_rank: Contributor
timestamp: April 28, 2023, 10:45:38 pm
content: That'll do it - read the damn data sheet, right! Thanks for the feedback.

author: Zero999
author_rank: Super Contributor
timestamp: April 29, 2023, 01:29:05 pm
content: Add a small diode, say 1N4148, in series with each output, with the anodes connected to RL.

author: MrAl
author_rank: Super Contributor
timestamp: April 29, 2023, 01:43:05 pm
content: Hi,Adding a diode may not get the output close enough to 0v.

author: Zero999
author_rank: Super Contributor
timestamp: April 29, 2023, 02:46:09 pm
content: Quote from: MrAl on April 29, 2023, 01:43:05 pmDefine close enough?The BA4560 is a bad choice. Its output will only be just under a volt or so of the negative rail to start with, so the low output will be around 1.5V with the diode and 10k pull-up.
windows ce - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 23, 2014, 03:38:23 pm
content: can you buy windows ce and install it on the raspberry pi

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 23, 2014, 04:01:54 pm
content: Short answer, no.Long answer, yes, but you need to have a lot of money and talk to the right people at microsoft. They only sell to OEMs, and only volume ones at that.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 23, 2014, 04:10:22 pm
content: Quote from: peter.mitchell on March 23, 2014, 04:01:54 pmWhat dose oem mean

author: Yago
author_rank: Frequent Contributor
timestamp: March 23, 2014, 04:14:36 pm
content: Original equipment manufacturer.

author: Len
author_rank: Frequent Contributor
timestamp: March 23, 2014, 04:16:16 pm
content: Quote from: abdullahseba on March 23, 2014, 04:10:22 pmCompanies that make hardware devices. They customize Windows CE for their own products. I haven't heard of anyone making a version for Raspberry Pi.It's now called Windows Embedded Compact, by the way.

author: FrankenPC
author_rank: Unknown
timestamp: March 23, 2014, 05:12:55 pm
content: Why would you want to run WinCE? Do you have some specialized application that is written for that micro-OS?If not, and you are simply trying to install something more Windows friendly, check out ReactOS.http://www.reactos.org/

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 25, 2014, 03:27:53 pm
content: Quote from: FrankenPC on March 23, 2014, 05:12:55 pmwould it work on the pi

author: Rigby
author_rank: Super Contributor
timestamp: March 25, 2014, 03:49:39 pm
content: Probably not very well, and you wouldn't want it to. The Raspberry Pi is not a powerful device. The CPU is pretty awful, truthfully.You'd have better luck with the BeagleBone Black, but you're asking questions that indicate that you don't really know how to make it happen, so nothing I say will be able to help you.I recommend sourcing a Windows Compact Embedded development kit or something, like this:http://www.e-consystems.com/DM3730-development-kit.asp.Or, you can play around in software with this:http://msdn.microsoft.com/en-us/library/jj200348.aspxIn any case none of it is electronics related, so you're not going to find a lot of help on this forum.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 25, 2014, 07:36:46 pm
content: Quote from: Rigby on March 25, 2014, 03:49:39 pmawesome
WinXP Drivers Infiniium 54854A - Page 1
Forum section: electronics / beginners

author: HiMyNameIsBenni
author_rank: Newbie
timestamp: July 14, 2022, 07:32:31 am
content: Hi,I had a problem with an Infininiium 54854A which I could not solve.So I wanted to reinstall the system (Windows XP SP3) and before that I saved the installed drivers, but unfortunately the hard disk on which the drivers are located is no longer usable.Could someone provide me with their drivers for the Infiniium 54854A?Many greetings,Benni

author: m k
author_rank: Super Contributor
timestamp: July 19, 2022, 01:46:53 pm
content: My guess is that repairing that faulty disk is a faster way.

author: Tony_G
author_rank: Super Contributor
timestamp: July 20, 2022, 06:09:52 pm
content: I have that scope and grabbed the files off the HPAK FTP site - Have a look here -https://1drv.ms/u/s!Amqar8_XQ9Uzj6YhN1xHdM8tQdKMOA?e=Ivwc7LTonyG
Wire connectors problems - Page 1
Forum section: electronics / beginners

author: SenSeS
author_rank: Contributor
timestamp: January 02, 2015, 06:48:00 pm
content: Hi, I'm looking to buy a cable like this with 6x1 pins with 100mil pitch and on the other side 6x1pins with 2mm pitch. Does anyone know where I can find one or do I need to make one of these? It would also be nice if the 6 wires would me more of a "strip" like an an AVR programmer for example. Some help with the names of the connectors and stuff would really help me in my search! Thanks

author: katzohki
author_rank: Frequent Contributor
timestamp: January 02, 2015, 09:16:32 pm
content: Connectors are a bit of a broad category. You could start here:http://www.digikey.com/product-search/en/connectors-interconnects/rectangular-connectors-headers-receptacles-female-sockets/1442548

author: Sebastian
author_rank: Regular Contributor
timestamp: January 03, 2015, 02:40:40 am
content: JST has this type of connector.
Need afordable version of wire crimping tool JST YRS-241. - Page 1
Forum section: electronics / beginners

author: BrianHG
author_rank: Super Contributor
timestamp: October 12, 2017, 05:45:31 pm
content: Help, I need an affordable version of this tool:https://www.digikey.ca/product-detail/en/jst-sales-america-inc/YRS-241/455-2047-ND/1634788I mean, 2K$, are they serious?Even on ebay, it's above 1K$.Where can I get a cheap identical one?
Wire for vacuum tubes and CRT ? - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: March 15, 2019, 07:26:40 am
content: I just ordered some cheap stranded copper-clad aluminium wire. And it's only good to 80V.I need a bunch of general hookup wire anayways.I have some vacuum tube radio's that's can need 400V, and I need to wire a CRT in a scope at some point too, that's up around 1200V. What kind of wire should I be looking for with the right insulation ?Copper plus shipping cost plus actual legit insulation = rolls of any brand name wire must cost a fortune. Where should I be considering in Canada to order wire ?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 15, 2019, 08:39:02 am
content: So, brand names, Belden, Alpha and such?Mail order from big distributors always sucks; it's alright if you just need a few and are buying other things too, but that's about it.More specialized distributors (check for local electrical supply stores?) may have better deals. Or there's always Amazon and such. You may even find distributors through their Amazon stores. Check the source carefully!Alpha 3071 and 782001 come to mind (600V), and any other mfg equivalent or similar will do. Hookup wire, machine wiring, general-purpose keywords like that. I'd prefer >90C max temp rating, which is the upper end for PVC then other (usually more expensive) types take over. 20 or 22 AWG should do for pretty much anything.Tim
Wire gauge and type to solder to IC pins - Page 1
Forum section: electronics / beginners

author: Legion
author_rank: Frequent Contributor
timestamp: June 07, 2014, 04:59:23 pm
content: I want to mod my N64 for RGB output. I'm following this guide:http://retrorgb.com/n64rgbmod.htmlIt requires soldering wires directly to the pins of an IC. I've never done that before so I'm wondering what gauge wire and stranded/solid to use?The smallest stuff I have is this 28AWG ribbon cable wire:http://www.digikey.ca/product-search/en?WT.z_header=search_go&lang=en&site=ca&keywords=MC10M-100-ND&x=0&y=0&formaction=onWill that wire be appropriate or do I need something else?

author: retrolefty
author_rank: Super Contributor
timestamp: June 07, 2014, 05:09:40 pm
content: i believe that 30 gauge wire-wrap wire (solid, very thin but strong insulation) is the most popular to use.

author: theatrus
author_rank: Frequent Contributor
timestamp: June 07, 2014, 05:20:04 pm
content: I too would recommend the 30-32 gauge Kynar solid. Once you are done, add mechanical strength by taping it down with some kapton tape or hot glue

author: Legion
author_rank: Frequent Contributor
timestamp: June 07, 2014, 05:37:06 pm
content: Thanks for the suggestions. I ordered 5 rolls of different color 30AWG kynar wire wrap.
wire strippers. - Page 1
Forum section: electronics / beginners

author: ShadyK
author_rank: Contributor
timestamp: April 05, 2014, 11:37:05 am
content: http://m.screwfix.com/p/forge-steel-160mm-wire-strippers/54067?filtered=truewill these be ok to use to strip coax cable ?? Or are they no good?

author: Unknown
author_rank: Unknown
timestamp: April 05, 2014, 12:07:11 pm
content: No good for coax; they're meant for standard insulated wire only.The same site has a couple of coax strippers - the rotary one is OK if you're doing the same type/size cable all the time, the other type is more useful for occasional use stripping different diameter cables.

author: scott216
author_rank: Regular Contributor
timestamp: April 08, 2014, 02:49:53 am
content: I use something like these:http://amzn.to/1ennPqqYou spin it around the wire.
wire to wire type connector for small dc motors - Page 1
Forum section: electronics / beginners

author: charles
author_rank: Contributor
timestamp: August 21, 2014, 05:00:11 pm
content: Hello,I have 4 small dc motors, take <400 mA each, that I want to connect to my circuit board. Thus, I have 8 wires that I need to hook up to the board. I was thinking the best thing would be to run 8 wires from the circuit board to some kind of 8 pin female type connector and then have the 8 wires from the motors be attached to the corresponding 8 pin male connector. I went on Digikey but was quickly overwhelmed. I thought that something like this would be appropriate:http://www.digikey.com/product-detail/en/794954-8/A30593-ND/701598andhttp://www.digikey.com/product-detail/en/794953-8/A30581-ND/701586But then I couldn't figure out how you are supposed to attach the cables to the connector; I noticed it says "Contacts Not Provided".Does anyone have suggestions on how these connectors are fitted to the wires and/or other good/better connectors for doing this?

author: wyphy
author_rank: Contributor
timestamp: August 21, 2014, 06:18:42 pm
content: Those look like they use pins very similar, if not identical, to those used in computer power supplies.You just have to find the pins on your supplier site; they probably come 100 to a bag for $3.00 or something.They are either crimp or solder, and you just put the pins on the wires, then insert all the pins into the connector.

author: Kremmen
author_rank: Super Contributor
timestamp: August 21, 2014, 06:32:33 pm
content: Check the Digikey product pages you linked. Towards the end you will find a list of "Associated products". Those are the pins that go into each slot. Connections by crimping or soldering just as wyphy said.
Wire Wrap Headers? - Page 1
Forum section: electronics / beginners

author: sci4me
author_rank: Regular Contributor
timestamp: October 02, 2016, 12:07:11 am
content: So I am looking to use wire wrapping. What I need are 4 pin headers such as these:http://www.digikey.com/product-detail/en/preci-dip/353-10-104-00-001101/353-10-104-00-001101-ND/4102234My question is, will these work just as well?http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=207165945&uq=636109453038710167If not, where can I find something that will work for me? Just has to be a 4 pin header like the one I linked, and, preferably, not terribly pricey as I'll probably need a fair number of them. Thanks!

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: October 03, 2016, 03:53:05 am
content: The second link doesn't lead to a product.BT

author: sci4me
author_rank: Regular Contributor
timestamp: October 03, 2016, 04:24:54 am
content: Quote from: BurningTantalum on October 03, 2016, 03:53:05 amUh, weird... does for me... *shrug*...

author: KL27x
author_rank: Super Contributor
timestamp: October 03, 2016, 05:19:06 am
content: Bulk pin headers are something I buy from eBay rather than electronic component distributor. Regular square pin header works great for wire wrap. Just search "long pin header."They snap. So a 20 pin header will be 5 x 4 pin headers.... pretty darn cheap from china, hong kong, etc. I can't be without 'em. You never know how many times you will have to tap the same connection while dev/debugging, and these make it a breeze. And they will fit in a female header/breadboard and you can wrap the other end, unlike what you showed in your first link.

author: Whales
author_rank: Super Contributor
timestamp: October 03, 2016, 05:56:55 am
content: Quote from: sci4me on October 03, 2016, 04:24:54 amSame here. Second link point to search results to digikey: "Results: 5,031,378". Try copying and pasting it into a different web browser: the link might only have significance with a certain cookie set.
Wire Wrap Sockets / Push Pins - Page 1
Forum section: electronics / beginners

author: pyromaniac4382
author_rank: Contributor
timestamp: July 13, 2015, 12:25:24 am
content: Wire Wrap Sockets / Push PinsI was looking around the internet for some deals on wire wrapping sockets for a sub 10Mhz digital design I have been working on recently. It seems like it is going to be a lot of money to get wire wrap sockets for each size DIP chip I am using. So I was thinking about getting breakaway wire-wrap sockets, but I was surprised to find only one supplier at a decent price. (~$2 for 40-pin SIP) So I was wondering if anyone has heard of a push pin type for wire wrapping that uses a single pin that will push into non-copper perforated PC board? It would be very helpful and probably a lot less expensive to get a whole lot of push pins and populate the appropriate number per DIP package. Does anyone have any experience with this? Thanks.

author: MarkF
author_rank: Super Contributor
timestamp: July 13, 2015, 01:56:48 am
content: I think wire-wrap is pretty much dead now days. If you could manage SMD parts and a small 4"x3" 2 layer board, you might consider making a PCB board withCadSoft EAGLE. It would probably be cheaper than wire-wrap.You may want to see if you can still find one of these boards:VME 6U Wire Wrap Prototype Board. I couldn't find their price.I just found thisMUPAC, wire wrapped, prototyping board NEW. Is a 3U board big enough?

author: edavid
author_rank: Super Contributor
timestamp: July 13, 2015, 03:31:11 am
content: Vector makes what you want, but they are not cheap:http://vectorelect.com/Catpdf/New%20Page%2075.pdfI would call up surplus stores and see if they have NOS sockets, or used boards you can unwrap.

author: kwass
author_rank: Frequent Contributor
timestamp: July 13, 2015, 05:42:09 am
content: Quote from: pyromaniac4382 on July 13, 2015, 12:25:24 amHere are some w-w machine pin sockets at decent prices:http://www.alltronics.com/cgi-bin/category/2831
Wired OR switch to enable DC/DC converter? - Page 1
Forum section: electronics / beginners

author: smoothVTer
author_rank: Regular Contributor
timestamp: November 27, 2017, 04:18:23 pm
content: My project contains a 4-position switch; OFF, MODE1, MODE2, MODE3. When in the OFF position, I want my DC/DC converter's ENABLE pin to be pulled low; in this state, the 3V3 supply for the uC is off. When either MODE1,2,3 are enabled, I want the DC/DC converter's ENABLE pin to be pulled high, and the uC then receives the 3.3V supply. The only constant power supply is the 9V battery. The switch is configured to short to ground one of 3 pins on the uC so the uC can read which mode it is in. There are external pull ups on all IO's.A picture is worth 1000 words:As you can see, the IO for the uC are shared with the switch positions and the ENABLE sense circuitry. I thought that using a diode-OR'd configuration would be a good start, so I wired up this circuit in LTSpice and gave it a go. What I observe is that my PNP can pull its emitter close to ground, but cannot reach the 9V DC level which would be required for the DC/DC converter enable pin.My question is: Is this the correct approach ( using a PNP in this case )? Is there a different topology which is simpler? Is there a topology I can use which uses MOSFETs only?

author: BrianHG
author_rank: Super Contributor
timestamp: November 27, 2017, 05:41:09 pm
content: Quote from: smoothVTer on November 27, 2017, 04:18:23 pmAre you sure?The vast majority of DC-DC converter enables, and even linear regulator enables trigger at around just above 0.7v. You know, so they can be compatibly driven by any 1.8v through 5v MCU IO pin.... Can you show me in the data sheet the voltage trigger threshold for the enable input?

author: smoothVTer
author_rank: Regular Contributor
timestamp: November 27, 2017, 06:07:18 pm
content: The converter is a LP2992 ( LDO ) with an enable threshold of 1.6VTechnically, this circuit could work: outputs ~0.7V low and a 3.9V high level. However I am uncomfortable with this 0.7V level and would like to take it below 100mV if possible.

author: BrianHG
author_rank: Super Contributor
timestamp: November 27, 2017, 06:19:23 pm
content: You could always use an NPN transistor...Actually, get rid of the transistor all together, reverse the diodes and the circuit should work...Or, for the cleanest output, in place of the diodes and transistor resistors, you can use a 3 input 74HCxx or 40xx or gate?

author: smoothVTer
author_rank: Regular Contributor
timestamp: November 28, 2017, 02:37:23 pm
content: I think the problem lies in that (a) the 3V3 supply is not on initially (b) trying to use the 3V3 as a pull-up (c) trying to share logic lanes on a 3V3 as well as a 9V supply. Of course I can use an OR style logic gate, but that must be powered off the 9V battery. However this 9V cannot ever touch the GPIO lines ... so I think this approach might not be feasible.
Wired, Wireless Audio Mixer - Page 1
Forum section: electronics / beginners

author: 76-7
author_rank: Newbie
timestamp: February 26, 2025, 04:04:41 am
content: Which chips and/or MCU (want to have a graphical user interface, rotary encoders/knobs for volume and EQualizer settings) would be suitable for multiple stereo audio inputs and outputs? What would I need to mix more than one input and have them play out over a single output?edit: I am considering ESP32-S3 (Wireless Audio); and RP2350 but do I need to have ADCs, DACs, and DSP to do audio stuff?

author: jwet
author_rank: Frequent Contributor
timestamp: February 27, 2025, 04:35:10 pm
content: Something interesting to look at is the TEENSY 3 or 4 with PJRC's Audio board. These can do cd quality audio DSP functions, the audio board acts like a sound card and has a stereo I2S codec on it. The biggest deal is that PJRC has written this amazing audio library that lets you drag and drop audio blocks and generates code that you can them plop into the Arduino environment. I think I've seen two audio boards on a single Teensy which might give your multiple inputs requirement. You could also make an analog mixer that you mixdown your input to the Teensy Audio board. An analog mixer is pretty simple but requires quiet rails and good layout.The missing piece is the wireless (assuming bluetooth) could just be a specialty audio to BT board or chip. I guess you could also pair the Teensy with ESP of some kind to fill the wireless need- can you feed I2S to the ESP stuff and have it transmit as audio?Sounds challenging but doable. Good luck.
wireless audio + amplifier: help me locate possible audio input  - Page 1
Forum section: electronics / beginners

author: chafporte
author_rank: Newbie
timestamp: May 18, 2020, 11:16:46 am
content: Hi, This is a 900mhz audio mono wireless analog receptor combined with a 10w amplifier. I would like to be able to input wired mono audio in the circuit (ie bypass all the radio parts of the circuit). The potentiometer at the top left in on/off + volume. The top right is channel tuning. black and red are optional battery supply. Blue red white at the top are going to a led to help the tuning. The other blue white red are filtered (tweeter+medium/boomer) signals sent to the speakers. I don't know much about electronic circuit, but I should be able to do the soldereing if someone can tell me where.Thanks for your help
wireless communication - Page 1
Forum section: electronics / beginners

author: abdulsamaddabu
author_rank: Contributor
timestamp: November 05, 2017, 03:53:17 pm
content: i want to send and receive data from 10 switch boards in my house for my new project of smart home automationi have three option for choosing wireless communication device:433MHz Wireless TX and RX RF Module:Its the cheapest one but can i attach 10 RX RF module to single RF TX module.ESP8266 Wifi MODULEWould i have to use arduino for it for each module ? or just i have to program it and will run without arduino ?can it be directly use for controlling relays instead of arduino ?NRF24L01 2.4GHz Wireless Transceiver Module:Would i have to use arduino for it for each module ? or just i have to program it and will run without arduino ?can it be directly use for controlling relays instead of using arduino ?

author: ebclr
author_rank: Super Contributor
timestamp: November 06, 2017, 09:10:47 am
content: Esp8266 ready made and cheaphttps://www.banggood.com/es/DIY-Wi-Fi-Wireless-Switch-For-Smart-Home-With-ABS-Shell-p-1019971.html?utm_source=google&utm_medium=cpc_elc&utm_content=rubio&utm_campaign=ds-arduino-pur-1103&gclid=Cj0KCQiArYDQBRDoARIsAMR8s_S1dPLF2OlwlLeqsydfteatRRmtjysBezG0TlYIi6qBz7WO7CCcXwwaAupSEALw_wcB&cur_warehouse=USA

author: onesixright
author_rank: Frequent Contributor
timestamp: November 06, 2017, 09:13:39 am
content: How much data (each time) needs to be send ad whats the interval?
Wireless mains remote master / slave switch module, where do I find one? - Page 1
Forum section: electronics / beginners

author: alcs2000au
author_rank: Contributor
timestamp: April 20, 2019, 08:39:40 pm
content: Hi guysI am trying to turn on some lights somewhere else in the house if the main lightswitch is turned on. Hence I am looking for a transmitter watching the status of the main light switch to then also set the receiver relay module the same way. Basically a remote wall switch with the wall switch replaced by a transmitter monitoring the preinstalled one.http://www.gentec.ca/eng/products/active-circuit-transmitter.aspI think this does what I am looking for, I am however looking for the correct name of this module as well as If there is anything like this on digikey or mouser that I can actually order.Thanks!

author: chagli
author_rank: Contributor
timestamp: April 21, 2019, 12:55:45 pm
content: Hi,The complete name seems to be ERM-DAU-277.I don't think you will find this kind of specialized module on Digikey.It could be a funny project though.

author: rstofer
author_rank: Super Contributor
timestamp: April 21, 2019, 02:17:09 pm
content: X10 system?https://www.x10.com/x10-home-automation/switches/cs277.html

author: alcs2000au
author_rank: Contributor
timestamp: April 21, 2019, 07:16:07 pm
content: Alright, I thought this was a standard product. If I have to do it myself I think ill do it with Sonoff and Tasmota. Thanks for the inputs! Wish there was a standard off the shelf solution out there that can easily be purchased...

author: soldar
author_rank: Super Contributor
timestamp: April 22, 2019, 03:57:32 pm
content: The requirements are a bit vague but it sounds like signalling over the powerline might be the way to go.
Wireless Power receiver for low power wearable - Page 1
Forum section: electronics / beginners

author: Day101
author_rank: Contributor
timestamp: April 24, 2020, 01:30:21 pm
content: I need wireless power charging for a low power wearable device. Lipo is only ~80mAh. Needs to be cheap, Almost no PCB space available. Coil size 24mm diameter ideally. Doesn't need to be quick at charging. Doesn't need to be Qi compatible.Whats the minimal circuit required to charge the lipo safely? All the Qi charger IC's I've looked at require a ton of ancillary components that take up lots of board space.There are also RF charging and Magnetic charging methods that look interesting, but I cannot find prices, Lapis ML7630 etc are not listed on findchips, octopart, mouser etc.Any comments are welcome.Thanks in advance,-Jason
Wireless power transfer question - Page 1
Forum section: electronics / beginners

author: chancs
author_rank: Contributor
timestamp: July 20, 2020, 02:30:36 pm
content: Hello EEVblog people,I need some helps on designing a wireless power transfer circuit that is going to charge a low power garget over 4cm to 5cm. The charging voltage is 5V and charging current is set to 100mA, so the RX side is 0.5W. Although efficiency isn't critical. But I hope no less than 25%.After few weeks of try and error. I only be able to power some LEDs. Can someone point me to some articles/books that I can read, or some projects that utilize WPT.Thanks,Sam

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 20, 2020, 05:43:04 pm
content: What area is available for the two devices?Tim

author: bob91343
author_rank: Super Contributor
timestamp: July 20, 2020, 05:49:42 pm
content: Most of these systems use the equivalent of an air core transformer. To gain efficiency, the frequency must be high to avoid the need for large inductances. Much of the signal is wasted in radiation. When the secondary is resonant it tends to capture more of the signal. This can be abetted by a directional primary. Use of directional antenna principles raises efficiency.Actually the intent is to maximize power transfer without regard of efficiency. A high voltage helps to reduce the effect of rectifier loss.I can't give you specifics because it depends on the mechanical configuration. It's mostly trial and error.

author: Vovk_Z
author_rank: Super Contributor
timestamp: July 21, 2020, 03:47:06 pm
content: Quote from: chancs on July 20, 2020, 02:30:36 pmAn actual wireless chargers (for smartphones) work with about 1-1.5 cm distance (+-). If I'm not wrong 4-5 cm make power 9-25 times lower. So it is not easy to have a 25% efficiency with the same size.
Wireless Telegraph - Page 1
Forum section: electronics / beginners

author: MasterSnipes
author_rank: Newbie
timestamp: March 30, 2015, 11:30:25 pm
content: So I'm making a wireless telegraph with the help of this guide:http://www.wikihow.com/Make-a-Wireless-Telegraphand I noticed I didn't have some of the parts he asked for. So I started thinking of alternatives such as aluminium foil for the 2 flexible pieces of metal and insulated wire for the electromagnet. I was wondering (since all of you are geniuses and have been a big help) if I could use this in my project.Anyways, THANK YOU SO MUCH!

author: AG6QR
author_rank: Frequent Contributor
timestamp: March 31, 2015, 12:14:23 am
content: The flexible pieces of metal must be something that is attracted by a magnet. At least the one that's pulled down must be. You might try using a food can, the kind used for soups, vegetables, etc. Check it with a magnet first to make sure it's magnetic. If there is any paint or other coating, you might have to scrape it off in order for the electrical connection to be made.Insulated wire should work fine, as long as you can fit enough turns on. The wire sold as "magnet wire" is actually insulated wire, but the insulation is very thin, normally a layer of transparent lacquer. More typical insulation can make it hard to pack the turns tight enough, but can work.That device looks like it would be a pretty nasty generator of broadband interference. I'm not sure what country you're in, but I wouldn't be surprised if it's illegal to operate such a transmitter. At the very least, please don't put much power into it, and please don't connect it to an efficient antenna.

author: Ian.M
author_rank: Super Contributor
timestamp: March 31, 2015, 01:03:53 am
content: The article in question is bogus.The metal strip will only be attracted to the electromagnet if its made of a ferrromagnetic material e.g. mild steel.Unless it is arranged to either short-circuit the electromagnet coil or open the circuit to the coil when it is attracted, it will have no noticeable effect. As illustrated, I do not believe the electromagnet could attract the strip arching over it enough to make it touch the other strip.The battery chosen is probably the most expensive and least effective commonly available one for the purpose.I suspect that as it claims 15 Co-authors, its been deliberately nobbled by radio amateurs who are not keen on people building illegal spark transmitters that cause broad-band interference. As I don't want every radio amateur here on my case, I'm not going to give any suggestions on actually making it workable!

author: MasterSnipes
author_rank: Newbie
timestamp: March 31, 2015, 10:19:10 pm
content: Quote from: Ian.M on March 31, 2015, 01:03:53 amSo I shouldn't actually make it? I'm just going to have it on for a few minutes to record a short video! What kinds of things could be affected? And one more thing, would this article be more useful:http://w1tp.com/perwirls.htm.And finally, do I need to have 2 metal strips or is 1 OK?
wireless transmission  - Page 1
Forum section: electronics / beginners

author: wolfrum
author_rank: Newbie
timestamp: May 18, 2012, 01:59:26 pm
content: I need to transmit about ((11 bits)X 12 devices) of data. I thought of using Xbee module as it is but it has only 7 digital pins.I need to use a microcontroller at the source and destination to decode the serial data.Are there any ways other Xbee. Can I use RF modules or something like that for each device. Will I get interference from other devices?
Wireless transmit large data/low power - Page 1
Forum section: electronics / beginners

author: A2
author_rank: Contributor
timestamp: August 13, 2014, 02:38:18 pm
content: I have battery operated application, in which I have to transmit data at 4Khz.Each sample contain 32x9 = 288bits.Is there any wireless IC/module which can tranfer 4Khz samples with each sample having 288 bits at very low power. i.e4Khz x 288 = 1152000 bits/sec

author: sunnyhighway
author_rank: Frequent Contributor
timestamp: August 13, 2014, 04:44:50 pm
content: Not sure if the range is sufficient, but serial over bleu-tooth might work for you.http://wiki.pinguino.cc/index.php/SPP_Bluetooth_Modules
Wireless transmitter/receiver?   - Page 1
Forum section: electronics / beginners

author: interoth
author_rank: Contributor
timestamp: July 05, 2012, 06:09:54 pm
content: Hey, I am working on a project that requires two boards to communicate.The idea is that when a input is given, a RS-NOR is flipped (to activate a relay) on another board up to about 10 meters away, then when pressed again it would flip the RS-NOR again to turn off the relay. I am having issues implementing a wireless solution. I have seen such chips as the Si4330 but am not sure how to implement it, or if it is overkill for my requirements.How might I go about achieving this?

author: Simon
author_rank: Unknown
timestamp: July 05, 2012, 06:21:53 pm
content: Are the boards supposed to be mobile or fixed ? How about infrared. Do you need to transmit any data ? How about generate s frequency and tune into it on the other board.

author: interoth
author_rank: Contributor
timestamp: July 05, 2012, 06:25:51 pm
content: IR is not a option as the other board is designed to be behind something. There is no other data than the 1 channel. How would I make a receiver that flipped the RS-NOR when it receives the signal?

author: Simon
author_rank: Unknown
timestamp: July 05, 2012, 06:32:51 pm
content: Depending on how critical and selective your application is build a basic oscillator of a frequency that is not in use and preferably legal to use. On your receiver side you need a basic am receiver that will produce a voltage when it gets signal

author: SeanB
author_rank: Super Contributor
timestamp: July 05, 2012, 06:40:20 pm
content: Or just buy a remote transmitter and receiver, and use the boards in the case to implement the function. A lot of the boards allow a pulse or a toggle output in the receiver, and allow multiple to be used without interference, though only one will work at a time.

author: interoth
author_rank: Contributor
timestamp: July 05, 2012, 06:44:06 pm
content: I am currently learning so I would rather make my own.I was wondering if there are any example schematics on the web? I had a look and can not find any.

author: SeanB
author_rank: Super Contributor
timestamp: July 05, 2012, 06:55:23 pm
content: Getting the RF side would be tricky without a lot of experimenting, or simulation on a RF package. Try tearing down some of the cheap controls, to get an idea of what they do with pcb tracks.

author: interoth
author_rank: Contributor
timestamp: July 05, 2012, 07:06:36 pm
content: I have been looking at some RC car's boards, but being a novice am not sure where to start.

author: vk6zgo
author_rank: Super Contributor
timestamp: July 06, 2012, 12:33:22 pm
content: One thing you could do is use Ultrasonics.You should able to find all the bits for this at your local Electronics shop,including coding systems for security..The advantage is that it can be less subject to interference than a simple radio system.The reason why there are complex remote controls is that simple ones can't cut it!