hybridfree/eevblog-posts huggingface dataset:
Sony NP-BN1 Battery Charger with TP4056 module - Page 1
Forum section: electronics / projects

author: NextCurrent
author_rank: Newbie
timestamp: March 22, 2020, 12:50:00 pm
content: Hi everyone, here is a simple project for any kind of lithium battery than can be charged with the TP4056 module.I've lost the charger for my Sony Cyber-shot DSC-WX7 camera so I decided to make one. The brain is the module that uses TP4056 chip and also the module has overcharging protection. ( you can find this module by this search: TP4056 5V 1A Lithium Battery Circuit Board Protection Board Charge Module )Also you will need thin plywood, or carboard, or other materials available to you. You will need 2 springs from pen, or you can cut 1 in half so you have 2, two wires, some hot glue, 5V power supply or I use 5V micro usb phone charger and thats it.Here is a video of it :thanks for watching

author: magic
author_rank: Super Contributor
timestamp: March 22, 2020, 06:13:24 pm
content: The protection chip isn't needed because TP4056/TC4056 (a few version of this IC exist) is a dedicated Li-ion charger with proper charge termination. It will charge the cell to 4.2V and leave it there, as it should. I suppose the protected version of this board is intended for installation in devices with built-in battery, to prevent discharging below safe limits. That's what the separate battery and output connections suggest.You may want to change the resistor which sets charging current. AFAIK something around 0.5C (half cell capacity per hour) is considered a good compromise between speed, safety and cell longevity.

author: NextCurrent
author_rank: Newbie
timestamp: March 22, 2020, 07:42:24 pm
content: Yes you are right ! The protected version is to prevent discharging below safe limits on connections on the output terminals. Thank you for you info.This battery its rated at 600mAh. I've measured for fully discharged battery (~3.6V) the charging current is around 300mA, then when it's around 4V charged the charging current drops to around 200mA and the charging stops around 4.1V for this battery.

author: magic
author_rank: Super Contributor
timestamp: March 22, 2020, 07:55:56 pm
content: Quote from: NextCurrent on March 22, 2020, 07:42:24 pmThis might be due to resistance of the USB cable or limited performance of the USB port. Use different port/cable and you may end up pumping 1A into the cell, which is the default setting on most of those TP4056 boards. IIRC, charging times faster than 1 hour are not recommended for Li-ion.

author: NextCurrent
author_rank: Newbie
timestamp: March 23, 2020, 07:59:31 pm
content: So I've tested this battery and other batteries (around 1000mAh) from older mobile phones with few different micro usb phone chargers (1 and 2A) , the charging current for this Sony battery was around 300mA but for the other batteries was like 700-800mA. Then I connected my bench power supply and measured around 100-200mA more charging current so yes i will need to change the programmed resistor that sets the charging current. Thanks
Sony Playstation Controller Pin - Page 1
Forum section: electronics / projects

author: carlossless
author_rank: Newbie
timestamp: October 14, 2020, 08:10:09 pm
content: Hello,I'm a newbie to this forum and still very much a newbie to electronic design in general.I'm currently working on a device that interfaces with the Sony Playstation and Playstation 2 controller ports. I want this device to be a self-contained module that plugs into the controller port and sticks out like usb dongle (no cables). I have the means to prototype cases and am working on several designs. I have one problem however...I have no idea what sort of pin this is. Is it a proprietary design or is it widely available?If it is proprietary, I saw some knockoff extension cables being sold on Alibaba. Would contacting the manufacturer be worthwhile? has anyone had experience with something similar that?Thanks!
Sony "surround" amplifier TA-SA100WR - Page 1
Forum section: electronics / projects

author: najrao
author_rank: Regular Contributor
timestamp: February 08, 2023, 08:32:54 am
content: I got this audio ClassD stereo amp, said to be in working condition. 2×80W rms with built in SMPS is something I would love to put to use. I also have the plug-in DSSS transceiver.Unfortunately, it seems it is only a part of an obsolete wireless streaming system, and needs at least a "master unit" with its own transceiver.I know nothing of this wireless method, but want to find some way of connecting an audio source, with or without wires.I found an excellent service manual, with schematics and pcb layouts, and I attach it below.Please would a guru advise me what to do.

author: David_AVD
author_rank: Super Contributor
timestamp: February 08, 2023, 10:19:01 am
content: I think you'll be wasting your time with that unit. Everything is done in the digital domain, right from the wireless board to the class D amplifier. The only analog section is for the headphone output, but you want an analog input?

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 08, 2023, 01:29:14 pm
content: Looks like it's just a matter of convincing it that there's a link (no idea how difficult that will be) and giving it I2S.
Sony Vaio DC power connector / CUI connector, need replacements - Page 1
Forum section: electronics / projects

author: Nzoomed
author_rank: Newbie
timestamp: February 03, 2024, 05:31:04 am
content: Im after a pair of these connectors, they are not actually needed for a sony Vaio at all, but thats the only thing i can find that uses them.I bought these from RS, and they arrived today, turns out they are too small and wont fit.All I know is that its a CUI connector, but cant find anything else in stock.https://nz.rs-online.com/web/p/dc-power-connectors/2596572https://nz.rs-online.com/web/p/dc-power-connectors/2596458When i took the measurements with my calipers on my plug, they appeared to match whats on the datasheet, but what ive got is slightly smaller.Any ideas?Edit:looks like i should have ordered this one?https://nz.rs-online.com/web/p/dc-power-connectors/2596460P?gb=s
Status Registers Help - SOP8 IC Chip  - TL866II+XGPRO - Page 1
Forum section: electronics / projects

author: wolfmight
author_rank: Newbie
timestamp: April 13, 2018, 10:30:14 pm
content: Just got the latest TL866II IC programmer with the latest XGPRO software 7.10 and latest firmware for the device.I'm still fairly new to this, but I needed some help with further explination of the status register configuration to successfully program a new 8MB Bios Dump to my MX25L6445E SOP8 IC (Bios Chip on a Asus ROG G75VX Laptop). I have a SOP8 chip clip successfully connected to the IC on the motherboard, software detects a successful connection and even identifies the correct IC per model text on the chip.The 8MB dump is from the exact same model and IC, however when I try to write to this current IC it's not writing anything but the 00s and FFs (I get verification errors for everything but the 00s and FFs) - basically seems write-protected (maybe OTP? One Time Programmable enabled?)I'm curious what these Status Registers mean and what I should have disabled and enabled for a successful write?I've attached a screenshot (see attached photo) of these in the software along with the datasheet for this specific IC - MX25L6445E SOP8 from MacronixThe status registers are:SRWD, QE, BP3, BP2, BP1, BP0, WEL(grayed out), BUSY(grayed out).Only QE is checked by default in XGPRO.What is the correct configuration to be able to program to this IC chip?ThanksDatasheet:http://www.macronix.com/Lists/Datasheet/Attachments/6636/MX25L6445E,%203V,%2064Mb,%20v1.8.pdf
Sorting out a pile of Ni-MH batteries AA/AAA - Page 1
Forum section: electronics / projects

author: RoGeorge
author_rank: Super Contributor
timestamp: March 02, 2022, 06:15:52 pm
content: Since I never throw them away, a few bowls full of rechargeables (mostly AAA or AA like the one in the pic) have piled up with time. Some are still usable, but most are refused by smart chargers. Though they can still be charged by slow chargers, but some batteries can still not power a photo camera, or they can power it but fail when trying to charge the flash, etc.Measured the dynamic resistance out of curiosity yesterday, with 1mA AC at 600Hz. Got various values between 500-800m\$\Omega\$, but the values seem to be irrelevant. Couldn't deduce the battery health out of it.The only quick way to find out the usable ones seems to be to short-circuit the battery with a DMM. Good ones can sustain 2..9A for a couple of seconds while short-circuited by the DMM. The weak ones can barely deliver 20..500mA when shorted.Though, the later ones can still be used in a small LED flashlight or other low current devices, but apart from the max current, there is another problem. Some are self discharging fast, in a matter of days, while other can keep their charge for weeks to months.- 1. Shorting the batteries with a DMM seems a little harsh, they heat in a matter of seconds. Does this hurts the batteries, should I add 1 ohm series or so?- 2. Any ideas how to probe faster for the self-discharge rate?

author: coppercone2
author_rank: Super Contributor
timestamp: March 03, 2022, 03:50:59 am
content: they are being current limited by the DMM shunt. If you use a different DMM you get a different current because they don't have a standard DMM shunt value, its always a trade off.I would say 3A from a AA cell is high but not excessive if pulse loaded, its common for things like motor battery powered devices to have a pretty huge inrush current. Flashlight affionados like NiMH cells because they have a low ESR so they can 'pulse' a flashlight good in strobe mode and generally power high power LED.Datasheets have a ESR range for the batteries. If you want to be safe get a momentary contact switch and a resistor to standardize the test.. for a D cell I think 10A pulse load is OK when NiMH actually.Just guessing but you can tryAAA - 1-2A testAA - 3-5A testC - 4-6AD - 6-8A (pretty sure I read some where on a flashlight forum about 10A being drawn from D cells being OK so long you monitor cell temperature.. I noticed some people really like to monitor their battery health and no one seems to be screaming about NiMH 'malfunctioning' because of pulse loading). When I build something with a D cell pack, I typically wire it with a 10A fuse.1 second should be plenty.I think this would be considered conservative for how some people use them. If you take apart a NiMH cell you will see its actually built pretty tough. My fluke scopemeter won't even turn on with low end brand alkaline C cells that have a higher voltage then NiMH cells, I assume because it can't provide some inrush?)
Sot-23 idetification: 2A* and 1Am* (pictures) - Page 1
Forum section: electronics / projects

author: Nexxen
author_rank: Regular Contributor
timestamp: September 15, 2023, 02:03:26 pm
content: Hello!!I'm close to finish a repair project but as the solder was compromised by a VARTA leaking I decided to remove and replace all the involved SMDs and SOT-23.SMDs are all 1206 and easy to find. SOT-23 have markings and I just want YOU pros to confirm my id.To me the 2A is MMBT3906LT1G (https://pdf1.alldatasheet.com/datasheet-pdf/view/203411/ONSEMI/MMBT3906LT1G.html);the 1AM is a MMBT3904 (2N3904) (https://pdf1.alldatasheet.com/datasheet-pdf/view/12488/ONSEMI/MMBT3904.html).Before I make a deadly mistake... can anyone confirm? I'm edgy about this because it's a 286 board and I prefer to say thanks twice than complain about how I should have asked.Here is the other thread of the repair:https://www.eevblog.com/forum/repair/desoldering-help-big-160-leg-ic/Many thanks in advance!!

author: DavidAlfa
author_rank: Super Contributor
timestamp: September 15, 2023, 02:13:53 pm
content: Seems like.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 15, 2023, 02:17:50 pm
content: There is no unambiguous mapping betwen SMD codes and part numbers. The search below gives a few suggestions, but there are more of such SMT lookup websites.https://alltransistors.com/smd-search.php?search=2A+sot23Also, 286 is pretty old, and it will not have transistors that are designed at a later date. It's a bit of a shame that datasheets often get updated and their dates changed without a revision table and no hint of when a certain part was first introduced.But if you want to be sure, the best way is to reverse engineer the part around that transistor and and verify whether the circuit diagram makes sense for the part you suspect it is.

author: Nexxen
author_rank: Regular Contributor
timestamp: September 15, 2023, 04:32:55 pm
content: After some more research I could establish that the two sdms actually are used in conjunction, thus it's the couple I should resolder.To what I've found any matching model is compatible and will work. In fact I found a few on other motherboards, even a couple I have in my parts bin.https://www.onsemi.com/pdf/datasheet/mmbt3904wt1-d.pdfI will however test them to check if they are still functional, as suggested. It won't hurt
SOT-23 TL431 pinouts - Page 1
Forum section: electronics / projects

author: Richard Head
author_rank: Frequent Contributor
timestamp: April 24, 2014, 05:38:35 am
content: I use TL431's in a SOT-23 package fairly regularly and have come across a pinouts problem.The TL431's I receive from a certain supplier have the TL432 pinouts but are marked as a TL431.I wonder if anyone else has come across this problem before?Dick

author: Whales
author_rank: Super Contributor
timestamp: April 24, 2014, 10:59:06 am
content: Incorrectly marked electronics are common, mainly intentionally rather than accidentally. A large part of the fab industry is to duplicate popular or expensive chips -- whether or not they are labelled as such varies.This isn't always a bad thing (as it lowers your costs), until you find a part that does not behave as you expected. Regardless of whether or not you trust your supplier, they themselves can be duped (or it could be a honest mistake). Make sure you test your part before redesigning a schematic (and get in contact with your supplier if you think they are reputable enough to care ).How many are you using? Hack: could you just manually bend the leads the other way and mount them upside-down?

author: Richard Head
author_rank: Frequent Contributor
timestamp: April 24, 2014, 01:18:57 pm
content: It's for production, which will be ongoing for several years. It's an industrial product so it's lifetime should be quite long.I only use one on each unit but it has to be correct as it's machine assembled.

author: nickm
author_rank: Regular Contributor
timestamp: April 24, 2014, 02:13:28 pm
content: Did you get the TLV431 by mistake? They will have the two flipped pins like the TL432.

author: theatrus
author_rank: Frequent Contributor
timestamp: April 24, 2014, 02:44:38 pm
content: Quote from: Richard Head on April 24, 2014, 01:18:57 pmFind a better supplier if they don't make this right.I have received wrong parts from even DigiKey, so stuff happens. Depending on your needs you can screen for this in your assembly process.

author: Richard Head
author_rank: Frequent Contributor
timestamp: April 25, 2014, 06:51:31 am
content: The marking on the package is exactly as you would expect for a TL431 so I don't think its a TLV431. I don't buy a reel, only 100 pieces at a time so I can't confirm what they actually are.I have been assured by the supplier that the packaging says TL431.I've been ordering them from another supplier until this issue is sorted out.Thanks for the feedback. Much appreciated.Dick
SOT23-5/6 SOT553 opamp most common? - Page 1
Forum section: electronics / projects

author: MT
author_rank: Super Contributor
timestamp: July 10, 2018, 12:54:11 am
content: Which +/-5V min supply , SOT23-5/6 SOT553 opamp are the most common , cheapest and always easy to get?Looking for "the 741 etc" in SOT packing.Thanks!

author: ahbushnell
author_rank: Frequent Contributor
timestamp: July 10, 2018, 01:59:32 am
content: Quote from: MT on July 10, 2018, 12:54:11 amNcs7101sn1t1g on semiSent from my SM-G930V using Tapatalk

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 10, 2018, 03:38:19 am
content: Hmm, I seem to have more than a few OPA170/171, but that may be more precision than you were looking for. TLV2371 is more that speed.Tim

author: IDEngineer
author_rank: Super Contributor
timestamp: July 10, 2018, 08:11:19 pm
content: Go to DigiKey.com, opamps, specify your desired package and supply rails, then inverse sort on "Quantity Available". The first few results will give you a nice snapshot of parts that are consumed, and thus stocked, in high(er) volumes. From there you can drill down to additional criteria such as performance and cost.

author: Zero999
author_rank: Super Contributor
timestamp: July 11, 2018, 09:47:30 am
content: The LM321, a single LM358/324http://www.ti.com/lit/ds/symlink/lm321.pdf

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 11, 2018, 10:06:21 am
content: Ah yes, they did make that in SOT:https://www.digikey.com/product-detail/en/texas-instruments/LM321MFX-NOPB/LM321MFX-NOPBCT-ND/3440175The ON Semi version seems to be the cheapest at DK right now. There's also the ST version,https://www.digikey.com/product-detail/en/stmicroelectronics/TS321ILT/497-4061-1-ND/720981Assuming, of course, you don't mind all the quirks that this old amp has.Tim

author: Kleinstein
author_rank: Super Contributor
timestamp: July 11, 2018, 04:21:58 pm
content: With the LM321 it's not just the normal quirks of an old OP, it is also the extra supply current of the 2 nd unused OP. Inside its more like an LM358 and thus the same no load supply current.Also don't confuse the LM321 with the old LM121 - that is a totally different (now obsolete) chip.

author: larsdenmark
author_rank: Regular Contributor
timestamp: July 11, 2018, 06:51:44 pm
content: How about the LMV321 and its friends? Are they considered modern?

author: 001
author_rank: Super Contributor
timestamp: July 11, 2018, 08:17:19 pm
content: Quote from: larsdenmark on July 11, 2018, 06:51:44 pmwhat is 'modern' for common opams?

author: MT
author_rank: Super Contributor
timestamp: July 12, 2018, 02:01:49 pm
content: 1: I have downloaded your proposals and now studying these!2: I have gone to Digi and done an inverse a search and now studying the result!3: I have noted the warning of quirky opamps in new packing!4: Had at first thought of OP171 but was a bit expensive (for the electrical function) at Distrilect.At first i pondered if 071 was available in SOT but no, which would had fitted the bill. I need the Gbp but not much gain.I thank you all for your suggestions and hints!
SOT23 package - Page 1
Forum section: electronics / projects

author: edwardcurrentclamps
author_rank: Contributor
timestamp: December 30, 2013, 11:49:37 am
content: Hey guys,just quick question on a little toasted diode I have here on a PCB. It is a SOT23 package and it is reading 6C12. I couldn't find any info online. Anyone an idea what values it has? Datasheet?Thanks for your help!

author: AndyC_772
author_rank: Super Contributor
timestamp: December 30, 2013, 12:22:39 pm
content: 6C is consistent with a BC817 transistor:http://www.nxp.com/documents/data_sheet/BC817_BC817W_BC337.pdf

author: ConKbot
author_rank: Super Contributor
timestamp: December 30, 2013, 07:26:44 pm
content: does the device have two leads connected? a diode connected transistor may be labeled as a diode on the board. I cant see what all is around it, so a diode connected transistor may be used for temperature sensing, or for biasing other transistors.

author: edwardcurrentclamps
author_rank: Contributor
timestamp: December 30, 2013, 11:58:28 pm
content: Well, if you are interested, here another picture with a bit more detail. Thanks for the help again!

author: envisionelec
author_rank: Frequent Contributor
timestamp: December 31, 2013, 03:16:56 am
content: It's a Rohm STZ6.8N dual, common anode 6.8V zener diode.http://www.mouser.com/ds/0/ROHM-Semiconductor/stz6.8n-32404.pdf

author: amyk
author_rank: Super Contributor
timestamp: December 31, 2013, 12:24:21 pm
content: I've noticed that for some reason, there have been an unusually large number of Rohm component identification requests recently.https://www.eevblog.com/forum/beginners/unknown-lcd-from-old-epson-printer-(rcd2226-rohm)/https://www.eevblog.com/forum/beginners/need-help-identifying-'45a-9081'-marked-tssop-eeprom/https://www.eevblog.com/forum/projects/can-you-identify-these-smd-parts/
Sound chips - Page 1
Forum section: electronics / projects

author: ldivision
author_rank: Newbie
timestamp: April 14, 2013, 03:14:30 am
content: Hello, I am looking at providing some sounds for my model railway. I have some MP3 files. Is there a sound chip that I could download these into and then select them individually from a switch or relay contact or some form of transistor switching. I hope to feed the output of this into a 12Watt universal amplifier module. Any ideas that could point me in the right direction would be appriecated.CheersMark

author: mariush
author_rank: Super Contributor
timestamp: April 14, 2013, 03:23:21 am
content: Have a look at this section:https://www.sparkfun.com/search/results?term=mp3&what=productsFor example, their mp3 trigger (https://www.sparkfun.com/products/11029) has 18 predefined pins for 18 tracks (just send some voltage on that pin and the player plays that track), or you can just send a command through the serial port to play one of 256 tracks you store on the SD card.You'll need an arduino or some microcontroller or some pc to interface with the board though.

author: David_AVD
author_rank: Super Contributor
timestamp: April 14, 2013, 04:12:16 am
content: The mp3 playback boards from Tenda are good value for money. I bought some direct from them a while back, but I believe some models are available through the kit suppliers. They have flash memory ones with USB download as well as SD card ones.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 14, 2013, 04:16:53 am
content: Convert the MP3s into raw PCM streams and then it would be trivial to use a microcontroller.

author: ldivision
author_rank: Newbie
timestamp: April 14, 2013, 05:56:12 am
content: Gentlemen, thanks for your replies that gives me a direction to go now.Cheers,Mark

author: Psi
author_rank: Super Contributor
timestamp: April 14, 2013, 08:27:23 am
content: There are examples of using an arduino to play wave files off an sd card.(If you feel like doing it with a micro)
Sound generator for alarm clock repair - Page 1
Forum section: electronics / projects

author: Martinn
author_rank: Frequent Contributor
timestamp: July 09, 2020, 05:28:48 pm
content: Hi all,my Braun analog RC alarm clock just died - alarm doesn't sound anymore. With great effort I was able to take it apart and found that all contacts, switches, wires (which I had thought would have been the problem) were in perfect condition. I think one of the glob top chips must be defective (radio and clock part still work, just sound and light don't work anymore), which means - this thing goes to the trash bin.Now I have to say I quite liked this clock. It looks nice (for a piece of plastic), was not super cheap and worked well so far. So I thought: Both the alarm "enable" (on top of the clock) and alarm "trigger" switches are purely mechanical and I could just wire them in series and switch on some sound generator with them. Now here comes the problem- we only have 1 AA cell (voltage say 1-1.6 V)- there is very little spaceand on top I dont want it to blare at full steam from the start, but begin with gentle short beeps, getting louder and longer continuously (as the original alarm did before it died).So on top of the 1 V supply and build volume limit, there needs to be some amplitude pattern. Speaker (still works) is dynamic, but as usual of helmholtz resonator style with probably large peak at it's resonance, so no point trying to play music.First I thought of some transistor oscillator circuits, but this would get pretty complex. The best (but least elegant) I can see right now is a charge pump or switchmode voltage converter to some > 2 V (Iq is no issue as it it switched off 99.99% of the day) and a small microcontroller with DAC (or maybe PWM) analog output (eg STM32F3). Sound could either be in a ROM table or synthesized (sine with some kind of envelope). However this feels like a huge overkill for a (well not so) primitive beep generator.Any better ideas? Maybe low power small media players one could use? Preferably single cell powered?Thanks, Martin
SOUND PRESSURE LEVEL METER - Page 1
Forum section: electronics / projects

author: uz1412
author_rank: Newbie
timestamp: February 03, 2020, 04:59:03 pm
content: Hi I want to build a sound pressure level meter using the atmega164p. I am unsure where to start. The objective is to sample a signal from a microphone and follow the envelope of the sound and display the signal level in dBs on some form of display. I know I need a sound sensor (microphone?) connected to an amplifier how would I decide on the right components for this? Please get back to me if you have knowledge on how to do this project. Thanks.

author: sam[PS]
author_rank: Contributor
timestamp: February 28, 2020, 06:52:45 am
content: For the electret mic preamp i'd strongly suggest to see the video Dave have made with Doug Ford on this very subject on EEVBLOG.If you don't expect too much precision the internal ADC might be enough. You might consider a variable gain preamp stage to increase your measure range without loosing too much precision.Then there is the question of the frequency weithing. SPL meter don't measure flat on all the audio spectrum, they use special frequency response curves to try to match human hearing. Those are A-weighting, B, C or D. The most common is A and would give you the dBA value. If you go analog a crude but simple approximation would be a 1st order bandpass filter centered around 2.5KHz and with a very low Q. You could of course also digitalise the signal and perform this filtering in dsp but i'm not sure atmega have enough computing power for that.Now it's about calculating true rms value, this can be done in digital on the MCU if you use a table for the square root or you can use an analog specialized IC before the converter, a crude version being a peak detector opamp circuit followed by a 1/2.8 voltage divider.For a simple version i'd go like this :electret mic -> mic preamp -> intermediate gain stage with stepped gain selector -> bandpass filter ~A weighting -> MCU ADC in @41.1kHz -> didital processing for RMS calculation -> and bob's your uncleThat would probably be a better measure then your smartphone SPL app, now if you want a really precise measure you'd probably need a better freq weighting and use a proper ADC. For a fully automated measure the intermediate gain stage should be digitally controlled. Of course all the analog part should be super low noise although i don't think anything out of the reach of a jellybean ne5532 except for the very first mic pre stage.Hope that gives you some hint of reflection.Just mu 2cts...
Sound/Vibration sensitive LEDs for tonal drum  - Page 1
Forum section: electronics / projects

author: fpvrcjohn
author_rank: Contributor
timestamp: April 02, 2015, 07:16:12 pm
content: Hi, I am working on art instalation project and have some difficulties with electronics, hope you guys can help meShortly about the project: Idea is to have 8 sets of leds with ADJUSTABLE sensitivity to 8 different notes on the percussion drum (drum:) The louder you play the note, the brigher the LEDs are shining. At least that's what I expect for..I was working on simple darlington transistor based circuits conetcted to piezo element that is glued on each note of the drum, it worked, but not well enough, the sensitivity was too low. I changed the transistors to AN6884 led driver circuit, the sensitivity is OK now, but LEDs do not fade out properly, they rather gradualy "blink out". Also they swich on to full power from any vibration, wich is not good as I want to have LEDs shining dim if I play silent on the drum and the louder it gets the brighter the LEDs shine. Other problem that I have with this scheme is that I can't connect as much leds as I need, because they get dimer.A I am quite short in time with this project (about 1 week for electronics) and have only beginer skills in electronics I hope you guys can suggest me some solutions to these problems. Maybe there is something already done for this? Or shall I use other sheme in general?Thanks, John
Source a transformer with multiple secondaries - Page 1
Forum section: electronics / projects

author: MarkF
author_rank: Super Contributor
timestamp: January 07, 2019, 06:17:10 pm
content: I would like to build a simple linear power supply with three outputs (i.e. 5VDC, +12VDC and -12VDC).I want to keep the 5V GND independent of the +/-12V GND. Only looking for a 1A capability max on each output.Does anyone know where I can find a single transformer with three secondaries instead of two transformers?

author: schmitt trigger
author_rank: Super Contributor
timestamp: January 07, 2019, 06:25:40 pm
content: Perhaps the easiest would be to purchase a toroid transformer which can provide the +/- 12v supplies, and then hand wind your own winding for the 5v supply. Window area allowing it, of course.

author: station240
author_rank: Unknown
timestamp: January 07, 2019, 06:57:22 pm
content: You can get multitap transformers, been out for decades.I have no idea where you get them in the US, all the electronics stores in Australia sell them.Try searching ebay for "transformer 9V+9V 15V+15V", seems to be some usable results there.

author: Benta
author_rank: Super Contributor
timestamp: January 07, 2019, 07:22:12 pm
content: Or just get it made to order. No big deal nowadays. There are transformer companies that'll make one-offs. Search the interwebs.

author: Zero999
author_rank: Super Contributor
timestamp: January 08, 2019, 09:34:45 am
content: Digikey sell them but the power rating for the 12V secondary is a bit less than your requirements, at only 250mA.https://www.digikey.co.uk/product-detail/en/signal-transformer/14A-30-512/595-1705-ND/1117954How about using two transformers or a switched mode power supply for the 5V part, which presumably isn't so sensitive to noise and ripple?Another option is to use a transformer with two secondary windings with one connected to a voltage doubler to get the +/-12V, although it would need to be considerably over-rated.
Source for 300-400 VDC, 1A power supply module, 48VDC input - Page 1
Forum section: electronics / projects

author: daqq
author_rank: Super Contributor
timestamp: October 23, 2014, 12:03:36 pm
content: Hi guys,for a project I need a module or a block that can supply a (preferably isolated) voltage (adjustable (preferably electronically) within the range of 300 to 400 VDC) at 1 Amp. The input should be 48VDC. Do you know of such a device? I've checked with VICOR and TRACO and the closest they've got is a MASSIVE (2kW+) overkill or full custom design.Thank you,David

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: October 23, 2014, 12:10:17 pm
content: Quote from: daqq on October 23, 2014, 12:03:36 pmUsing multiple isolated converters with outputs in series might be an option.

author: calexanian
author_rank: Super Contributor
timestamp: October 23, 2014, 02:58:12 pm
content: I was looking to do something like this. I ended up just building my own isolated switching supply. It was easier to scrounge up parts than find something ready made.

author: daqq
author_rank: Super Contributor
timestamp: October 26, 2014, 10:53:50 am
content: Thanks for the tip Mike, I'll look into it.

author: Strada916
author_rank: Frequent Contributor
timestamp: October 26, 2014, 10:58:49 am
content: Two transforms primary to mains. Secondary to secondary. Primary 240vac rectified and filtered you will have around 300 to 400vdc. And isolated.

author: Strada916
author_rank: Frequent Contributor
timestamp: October 26, 2014, 10:59:28 am
content: Sorry did not see the input bit.

author: SeanB
author_rank: Super Contributor
timestamp: October 26, 2014, 05:03:01 pm
content: Look at appnotes for most SMPS IC's and you will find in there the telecoms apps where the input is 48VDC, and then wind a transformer to give the 400V output and use either controlled attenuation on the feedback or an external linear regulator to give the variable voltage.
Source for affordable (cheap) plastic or isolated BNCs? - Page 1
Forum section: electronics / projects

author: cdev
author_rank: Super Contributor
timestamp: November 20, 2017, 02:52:42 am
content: It seems that I may need to use isolated, non grounded BNC connectors in a conversion I am doing of a video distribution amp for timing. I think this means I have to float some of the BNCs using isolation transformers. A few days ago, somewhere, it may have been here, I saw somebody had purchased a bag of black plastic shelled BNCs with internal metal connections. I think that is what I need. Anyway, suggestions are welcome.EDIT: I have found some isolated BNCs and they will probably be adequate to the task. I'm going to wait until the unit arrives to purchase them in case this unit (An Extron distribution amp) has the awfully inconvenient D shaped holes.

author: tautech
author_rank: Super Contributor
timestamp: November 20, 2017, 09:23:54 am
content: xrunner thought he had a similar problem to replace an insulated BNC in his Tek FG502 but they are available it seems:Quote from: MarkL on May 31, 2017, 08:11:35 pm
Source for an optical mouse sensor like the ADNS2620? - Page 1
Forum section: electronics / projects

author: ledtester
author_rank: Super Contributor
timestamp: June 29, 2020, 05:14:34 am
content: I'm looking for an optical mouse sensor like the ADNS2620. I would need more than a few but probably less than 50.I mention the ADNS2620 due to its ease of integration with a microcontroller.I know you can get optical mice from China for around $2 each, but it would be nice to get a chip with a datasheet.Any ideas?

author: dmendesf
author_rank: Frequent Contributor
timestamp: June 29, 2020, 02:18:26 pm
content: You can buy these chips in large quantities at Alibaba / AliExpress. Probably easier to source newer models like adns3050. As these are used primary in mouses (all made at China) the supply chain is all there. Do you also need the plastic lens? I've never seen these being sold alone but probably you just need to ask the chip seller.

author: ledtester
author_rank: Super Contributor
timestamp: June 29, 2020, 04:03:44 pm
content: Thanks for the pointers... searching for "ADNS" brought up hits for the chips and lenses.I also found these chips: PWM3660, PAN3512.I wonder what other part numbers I might search for.

author: EverydayMuffin
author_rank: Regular Contributor
timestamp: September 07, 2020, 06:29:49 am
content: The Avago Navigation Division was acquired by Pixart in 2011 so the ADNS parts are now available from Pixart. The Pixart distributors are EPS Global in Europe and WPG in America.I think the ADNS-2620 is EOL, Pixart have the PAW3220DB-TJDR and PAW3212DB-TJDT which are both in an 8-pin DIP. The PAW3220DB-TJDR is higher resolution.PAW3212DB-TJDT WebpagePAW3212DB-TJDT Product BriefEdit: Added PAW3220DB-TJDR which is higher resolution.

author: EverydayMuffin
author_rank: Regular Contributor
timestamp: September 17, 2020, 01:52:42 pm
content: If you're interested in working with ADNS-2620 or PAW3220DB, there is an "Open Source Mouse" project on github here:https://github.com/biomurph/MouseCurrently it supports the ADNS-2620 but looks like he will also migrate to PAW3220DB.
Source for BNC RG58 male pins - Page 1
Forum section: electronics / projects

author: JacquesBBB
author_rank: Frequent Contributor
timestamp: December 14, 2015, 08:36:18 am
content: I am searching forRG58 BNC golden male pins for solder, for replacement in BNC plugand have difficulty to locate them in the main distributors sites.Does anybody have a proper source for these ?
Source for decent quality surplus speakers in the UK? - Page 1
Forum section: electronics / projects

author: microbug
author_rank: Frequent Contributor
timestamp: April 01, 2014, 02:02:24 pm
content: Inspired by the recent Hackaday post, I have decided to make a portable Li-Poly powered boombox. I am thinking 4x3W 4r mid-range speakers (or maybe 2x6W) and one 15-20W subwoofer.I remember reading a while ago on the forum that you can get surplus / outdated speakers of good quality for a comparatively low price, but I can't find any sites: suggestions? I am in the UK.My budget is a total of £50.

author: peter.mitchell
author_rank: Super Contributor
timestamp: April 01, 2014, 02:45:35 pm
content: No idea sorry. However, if you wish to stoop down to car audio speakers, they can be had pretty cheaply; currently these are on sale with free shipping;http://www.caraudiocentre.co.uk/product_m-kenwood-kfc-e1052_p-26123.htmThat and a reasonable class d amplifier should be quite nice in a boom box. No real need for a subwoofer IMHO.

author: calexanian
author_rank: Super Contributor
timestamp: April 01, 2014, 06:55:41 pm
content: The problem with Surplus speakers in particular, it it typically means broken speakers. Just get yourself some cheap 2 way auto speakers. That should do the trick! Many times your auto parts stores will have some cheap models, and there is always online.. You might be suprized how good a $20 auto speaker can actually sound for just a boom box type thing.

author: microbug
author_rank: Frequent Contributor
timestamp: April 01, 2014, 07:04:45 pm
content: Ok, I will. I see that the 2-way (or even 3-way) ones have built in tweeters (+midrange for 3-way) so that sounds good.Thanks!
Source for dual tact switches? - Page 1
Forum section: electronics / projects

author: gregallenwarner
author_rank: Regular Contributor
timestamp: January 08, 2015, 08:08:08 pm
content: I'm designing a piece of musical equipment--a uC-powered metronome. I'm using one of those extruded aluminum enclosures that you can find on eBay. I chose a particularly small one, because I'm aiming to design this to be ultra compact. Anyway, I need some of those right-angle mounted dual tact switches, the kind where the two tact buttons are stacked vertically in one metal frame for PCB mounting. However, I'm looking for some ultra small formfactor switches. Most tact switches are 6mm square, but the dual stacked ones I've found are something like 22mm high or some number right around there. My enclosure's only got 15.4 mm clearance from the surface of the board to the top of the case.I have seen on occasion some smaller-than-usual 4.5 mm square tact switches, however, I've never found a dual stacked right-angle configuration using these. I'm wondering if anybody can help me either find something like those, or come up with some other solution that will allow me to have two ultra tiny tact buttons mounted at a right angle within my space limitations? I'm trying my hardest not to have a secondary PCB as the front panel. If I can mount absolutely everything on the one PCB that slides in the extrusion, that'd be ideal.Thanks!
Source for genuine (or known good) HC-12 modules qty 100 - Page 1
Forum section: electronics / projects

author: Jester
author_rank: Frequent Contributor
timestamp: February 22, 2022, 02:45:09 pm
content: Apparently there are a lot of defective clones, I'm looking for a source for qty 100 to start with HC-12 transceiver modules.Any suggestions?Thanks J
source for good quality inexpensive USB chargers and cables? - Page 1
Forum section: electronics / projects

author: ralphd
author_rank: Frequent Contributor
timestamp: October 15, 2015, 11:47:35 pm
content: I'm getting tired of searching for inexpensive yet decent quality USB cables and chargers.I just finished testing a few $1 chargers that were rated for 1A. I was hoping I'd actually get 4-500mA @4.75V out of them. The tests charging a moto G weren't even close:#1: 0.3A & 4.65V#2: 0.25A & 4.6V#1: 0.3A & 4.55VSimilarly, I've had a hard time finding cheap USB charging cables with decent gauge wire in them. One of the cheap cables I took apart had a resistance of ~3 Ohms for a 75cm conductor that looked even smaller than 30AWG wire-wrap. Even at $2.40/lb for copper, a cable mfr could afford to put 26AWG wire in their $1/1M cables.

author: mariush
author_rank: Super Contributor
timestamp: October 16, 2015, 02:32:01 am
content: First of all, get proper chargers, not shitty iphone charger clones that won't do more than 500mA in the first place. Just because the label says 1A, doesn't mean that chinese crap can do 1A.As for cables, there's plenty of places where you'll find good cables, from stuff likeAmazonBasicstomonoprice.com(which even lists the awg gauge of the cables where available) and plenty of other reputable sites.If you go cheap, you just waste money.And here's a page that tests 12 different chargers , that can be bought in stores:http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html

author: SteveLy
author_rank: Regular Contributor
timestamp: October 16, 2015, 02:20:56 pm
content: Now you know what a $1 USB charger/5V-supply can do. You have to lower your expectations / compromise re "inexpensive yet decent quality". It's $1, a buck, a one buck device: what do you expect, miracles? Try something around the $10 mark.

author: GNU_Ninja
author_rank: Regular Contributor
timestamp: October 16, 2015, 02:37:02 pm
content: This video by MikesElectricStuff taught me to be wary of One Hung Lo wall warts and what have you. After watching that, I now NEVER plug one of those suckers in until I've taken it apart first.
Source for illuminated rotary encoders - Page 1
Forum section: electronics / projects

author: mubes
author_rank: Regular Contributor
timestamp: May 18, 2014, 09:40:06 pm
content: Folks,Does anyone have any good sources for illuminated rotary encoders (preferably rgb)? Sparkfun have one but it has an 18mm spindle and I was hoping for something a little more low-profile...I'm also open to other approaches if anyone can suggest one. The intended result is an illuminated rotating dial with integrated push button...perhaps someone can suggest a knob/light pipe combination that will do the biz?RegardsDave

author: tinhead
author_rank: Super Contributor
timestamp: May 18, 2014, 09:55:32 pm
content: http://www.top-up.com.tw/front/bin/ptlist.phtml?Category=325301

author: mamalala
author_rank: Unknown
timestamp: May 18, 2014, 10:12:14 pm
content: If you have enough space, and like to have a rather decent desing of the knob, you can try one of these:http://www.okw.co.uk/products/okw/star-knobs.htmGreetings,Chris

author: mubes
author_rank: Regular Contributor
timestamp: June 01, 2014, 01:31:13 pm
content: Thanks for the input folks. Top-up are interesting but I'm yet to manage to extract any pricing from them....I seem to have fallen into that cycle of tell-us-everything-about-yourself-and-we'll-decide-if-we-want-to-sell-to-you that sometimes happens. The others are also pretty cool but not really suitable for a high-volume, low cost product for arbitrary cases that I'm hoping for. Low volume the top-up parts are available for about £4 from various uk vendors, but that's way too expensive for what I can cope with.I'm amazed that I've not found any 'collars' or similar that can sheath a standard knob to illuminate around it .... They're pretty common in the automotive world (e.g. The night illumination on a modern BMW) but I don't see them available non-bespoke...that would be the best/cheapest approach for this kind of application, but I just can't seem to find them....I guess I'm just searching for the wrong things.I'll update this thread with my findings when if know more.RegardsDave
Source for LED color mixing/diffusing lenses  - Page 1
Forum section: electronics / projects

author: Corporate666
author_rank: Unknown
timestamp: January 30, 2014, 05:21:53 am
content: I know there are various optics out there designed for color mixing discrete R, G, B emitters... but what I am looking for is the sort of lenses you see on standard LED bulbs you can buy at home centers. It's essentially just a milky white plastic - but of course the color and thickness are engineered for the best compromise between light transmission and blending.I know most of the LED bulb makers just fabricate the lenses for the specific product in question, but there has to be someone (probably in China) making something like hemispherical white/transluscent plastic domes for generic applications?Lots of snooping around Alibaba has turned up little - perhaps I am using the wrong terminology, or maybe someone knows a source?

author: Towger
author_rank: Super Contributor
timestamp: January 30, 2014, 07:58:52 am
content: I am on phone at the moment, but if you Google 'Lee filters frost' you will get white sheets of light diffusers in different strengths. They are used in stage lighting.

author: Corporate666
author_rank: Unknown
timestamp: January 31, 2014, 04:36:56 pm
content: Quote from: Towger on January 30, 2014, 07:58:52 amThanks, I checked it out - may work. The only issue is I was hoping for a hemispherical shape but I am sure I can work something out.

author: scientist
author_rank: Frequent Contributor
timestamp: January 31, 2014, 06:33:46 pm
content: You could vac-form it with a heater and foam ball.
Source for low cost (plastic) shell for euro card? - Page 1
Forum section: electronics / projects

author: nctnico
author_rank: Super Contributor
timestamp: October 27, 2013, 09:31:14 pm
content: I need some pointers to source the following:I'm looking for a low cost housing to put around a eurocard. The card sits inside a rack most of the time but I've noticed the customer isn't too carefull about ESD and so on. I've seen these at Farnell but those are a bit expensive and way too tedious to put together:http://uk.farnell.com/schroff/20846-636/card-frame-3u-167mm-10hp/dp/1370423What I need is basically a shell which protects the PCB during handling and transport which fits into a 19" subrack.
Source for Micro HDMI female to HDMI female CABLE?? - Page 1
Forum section: electronics / projects

author: alext
author_rank: Regular Contributor
timestamp: February 11, 2017, 02:09:09 pm
content: hey.im looking for a Micro HDMI female to HDMI female CABLE but i just find the adapter version which is too thickdoes anyone know a source for this cable?or may i have to modify a different cable?does hdmi crimping is difficult?im guess it is,since the many pinsthanks