hybridfree/eevblog-posts huggingface dataset:
Egnater Tourmaster 4100/4112 Midi Footswitch - Page 1
Forum section: electronics / projects

author: dlfstone
author_rank: Newbie
timestamp: October 12, 2024, 05:39:42 pm
content: Good morning - New to the site...I just bought a Egnater Tourmaster 4100 head for a great price, but it didn't come with the 6 button footswitch controller. Does anyone know if it would be possible to buy a midi controller and assign the buttons to control the Eganter head? I've scoured the internet and there are no Egnater TM footswitches for sale. The original midi footswitch has the following 6 buttons:- Switch #1: Clean Channel 1- Switch #2: Clean Channel 2- Switch #3: Overdrive Channel 1- Switch #4: Overdrive Channel 2- Switch #5: FX Loop On / Off- Switch #6: Reverb On / Off
EGS002 based inverter overcurrent protection - Page 1
Forum section: electronics / projects

author: ambrozy
author_rank: Contributor
timestamp: April 28, 2025, 06:21:49 pm
content: I'm building EGS002 based inverter with 4x IPP086N10N3GXKSA1 mosfets and 600VA toroidal transformer, input voltage ~60V. I've read that overcurrent protection on EGS002 is junk and it blows up mosfets when toroidal transformer is used, supposedly the problem is with LM393 which shuts down the mosfet drivers abruptly. From what I can infer from the datasheet LM393 shuts down the drivers when IFB is >0.65V but there is also another protection with 600ms delay that has 0.5V threshold, does just removing LM393 "solve" the issue?Another question is what with short surges, I want to power a PC from this and turning on ATX PSU is a big current surge, what to do about it? How to make the inverter robust to such surges?

author: jwet
author_rank: Frequent Contributor
timestamp: April 30, 2025, 06:10:04 pm
content: Its more likely that the FET's are getting hit with spikes greater than their specs. In a 60V input inverter, I would use a FET with a Vds spec of >150V. There are stray inductances and capacitances in driving a transformer and at these power levels, they have some energy behind them. A 100V rated part would not be likely to last long. Inverters and other high voltage switching circuits are pretty hard to make reliable without some careful design.The LM393 circuit is kind of a supervisor that doesn't allow operation without 5v and monitors the bottom of the H-Bridge for over current. This is pretty benign and I wouldn't operate without it.Is there a reason that you can't buy a 600w, 60v input inverter- they're less than $100 on Amazon etc and probably cheaper on Alibaba?

author: ambrozy
author_rank: Contributor
timestamp: May 01, 2025, 11:33:13 pm
content: Quote from: jwet on April 30, 2025, 06:10:04 pmI don't know where you see it supervising 5v, I removed it and it worked (more on that later).Quote from: jwet on April 30, 2025, 06:10:04 pmThis is more of a prototype I have bigger transformers and want to use those eventually.So I removed LM393 and connected IR shutdown pins straight to ground, it worked, I tried it with a PC with Corsair SF450 PSU, I put 3.6ohm resistor in series with the transformer to lower inrush current a little, it worked fine, then I tried with another PC with be quiet PURE POWER 12 650W and despite the resistor it immediately blew up the mosfets on startup. Would a fast-acting LM393 overcurrent protection save the transistors? perhaps, or perhaps it would itself cause a deadly surge by stopping running 50hz transformer suddenly, but actually it doesn't matter anyway, it wouldn't have worked with the be quiet power supply anyway, so now all that remains is to select transistors big enough that they would withstand those inrush current pulses, this is the most straightforward solution right?
EGS002  H-bridge inductor - Page 1
Forum section: electronics / projects

author: Qrdi86
author_rank: Newbie
timestamp: May 17, 2023, 03:55:04 pm
content: "Hello, I am planning to build a converter using the EGS002 module to convert 350VDC to 230VAC. My question is regarding the inductance of the choke and the type of core to use. It seems that the yellow core commonly used for smoothing computer power supply output voltages may not be suitable. However, the power supply's power factor (PF) choke might be suitable. Also, what should be the maximum output current when using these output transistors(good cooling), to which I will add the load according to the provided diagram?"https://www.farnell.com/datasheets/3672794.pdf(I don't speak English well and I used chatgpt help.)

author: moffy
author_rank: Super Contributor
timestamp: May 17, 2023, 10:38:58 pm
content: For the choke material you could use Ferrite or an Iron powder core.
EIA-96 rant - Page 1
Forum section: electronics / projects

author: DavidAlfa
author_rank: Super Contributor
timestamp: May 08, 2022, 07:59:43 pm
content: The usage of these seems to be increasing in the recent years.So, we're already doing 2nm lithography, but a 4-digit code wouldn't fit, instead they paid a psychopath to make a new coding system.It really annoys me, you're screwed up unless having a decoder or a look-up table, having to check every value on the computer slows things down a lot.If the part gets partially damaged, good luck trying to figure the original value.Do you have any mental trick to decode them?

author: magic
author_rank: Super Contributor
timestamp: May 09, 2022, 05:35:55 am
content: Quote from: DavidAlfa on May 08, 2022, 07:59:43 pmWell, yes. Just take the 96th root of 10 and raise it to the power of the number printed on the resistorProblem?BTW, I mostly agree. I wrote this, but it still doesn't help if you are away from a computer.https://www.eevblog.com/forum/chat/small-and-stupid-decoder-for-eia96-resistor-markings/

author: perdrix
author_rank: Frequent Contributor
timestamp: May 09, 2022, 09:59:21 am
content: OMG I hadn't hit any parts that used that insane marking yet! What **** **** dreamt that idiocy up.David
EIA Production Date Codes - Page 1
Forum section: electronics / projects

author: jaycobie
author_rank: Contributor
timestamp: March 27, 2020, 01:09:48 pm
content: If anyone interested in older electronics is looking for stuff to do in these isolated times, I just wanted to highlight my EIA Code Compilation.The EIA Production Source Codes (or EIA Production Date Codes) were used from 1946 to 2001 (and beyond) to identify, through numerical codes stamped on electronic components, transformers, speakers and more, when that item was made, and by what company.Because the history of these codes is not compiled in any one place, and some of the company codes changed hands over the decades, I wanted to document the history as much as possible. It's also nice not to have to look for this information on scanned pages of old documents.I've transcribed 21 separate EIA code lists (1946, 49 to 63, 65, 81, 89, 94, 95 and 2001) into a single Google Sheets spreadsheet, which anyone can access or download copies of here:https://docs.google.com/spreadsheets/d/1P1jeVIQ9UdwlhXTDLQEDxYuShjFQZO_4tUchw5_8N9o/I'm still missing plenty of years, so If anyone has access to physical copies of EIA Production Source Code lists from the following years, and could scan them, please send them to me (j@reverb.is).I will transcribe them into to this public compilation for all to benefit from.Years I'm missing:1948194919641966to1980(and all inbetween)1982to1988(and all inbetween)1990to1993(and all inbetween)1996to1999(and all inbetween)
EiceDRIVER Gate drive and connecting source and sing to use single resistor - Page 1
Forum section: electronics / projects

author: Miyuki
author_rank: Frequent Contributor
timestamp: September 29, 2021, 05:13:24 pm
content: Hi folks,I have a question and cannot find it in the datasheet or application sheetsCan I safely connect the source and sink output on Infineon EiceDRIVER with separated outputs like1EDI60I12AF?I will have a gate resistor of about 25 ohms.I know they have different drivers, but this one is the most abundant with a 40V output rating.

author: uer166
author_rank: Super Contributor
timestamp: September 29, 2021, 09:09:54 pm
content: I don't see why not, it's just a push-pull split to allow different resistor values. I also see no point in doing that since you can simply use two resistors of same value and keep it as intended (split output). Also, why wouldn't you want to take advantage of it in the first place? Having a higher sink current vs. source can help with a bunch of things.

author: Miyuki
author_rank: Frequent Contributor
timestamp: September 30, 2021, 06:47:28 am
content: The block is not complete, they say that even high output can sink 100mABut I agree, just put two resistors even if they will be the same is not a problem

author: Wolfram
author_rank: Frequent Contributor
timestamp: September 30, 2021, 07:46:55 am
content: They might rely on having (Rgh+Rgl) between the two outputs to limit shoot-through current in the output stage during switching, so I would recommend keeping the original resistor configuration.
EICO Model 460 Custom Computer - Page 1
Forum section: electronics / projects

author: PDX460
author_rank: Newbie
timestamp: March 27, 2019, 10:57:44 pm
content: Hi Everyone,I recently converted an EICO Model 460 Oscilloscope into a custom computer and thought I would post pictures of the completed work here.When I first started this project, some members of this forum answered questions for me on the disassembly, which I found extremely useful and helped me not get electrocutedOriginal OscilloscopeAfter I started the project, I decided to add a base to the main box.The base started out looking like this:Completed ProjectSpecsMotherboard: Asus H270M-PlusCPU: Intel i7 7700kMemory: Corsair Vengeance RGB 32GB DDR4Graphics: EVGA GeForce GTX 1080 FTWStorage: Toshiba/OCZ 500 GB M.2 NVMe (Windows Drive)Storage: Crucial MX500 1TB M.2 SATA (Storage Drive)If you would like to see a full detailed work log, you can check it out here:https://www.overclock.net/forum/18082-builds-logs-case-mods/1723250-high-voltage.htmlThanks

author: Wimberleytech
author_rank: Super Contributor
timestamp: March 27, 2019, 11:24:44 pm
content: Nice work! Cool.
EKG circuit analysis - Page 1
Forum section: electronics / projects

author: smashedProton
author_rank: Frequent Contributor
timestamp: March 16, 2013, 03:26:29 am
content: I would like to propose an exercise for you guys. I also don't understand some of the stuff myself. What is the third lead on the ankle and the isolation barrier for? There is only 6 volts pp here.. Could you just take the potential difference across the heart and then filter out the noise? Im way out of my league here. If you are wondering why I am torturing myself like this. It is because Im going to see if my physics teacher will give me credit for doing related work outside of school. Now that I think of it, I can convince her that I'm a wizard just by turning on an LED.

author: David_AVD
author_rank: Super Contributor
timestamp: March 16, 2013, 03:38:47 am
content: I'd say the third lead would be so you can use a differential measurement and reject any common mode (movement?) noise.The isolation is because a failure on the PC / instrument side that applies excessive voltages to the patient would be bad.

author: mtdoc
author_rank: Super Contributor
timestamp: March 16, 2013, 04:47:44 am
content: Your picture is not showing up for me but in general each of the limb leads is important for ECG analysis. The limb leads form Einthoven's triangle. Part of reading an ECG is a form of vector analysis which helps localize the dominant electrical forces during the depolarization wave across the heart muscle (the cardiac "Axis"). All the limb leads are necessary to do this.A "real" ECG used in medicine actually uses 12 leads and the combination helps to anatomically localize specific problems.Hope that helps - not sure how to explain it better. Have a look atTHISWiki article - it might be more helpful.

author: penfold
author_rank: Frequent Contributor
timestamp: March 17, 2013, 09:16:30 am
content: I seem to remember from somewhere I can't quite remember that the ankle straps work as a 'guard'. Its a technique commonly used to reduce stray leakage currents, if you lookup guard rings and traces for PCB layout, then it'll probably give a bit of a clue what they're all about in your context.
El-cheapo Volt / Current reference - Page 1
Forum section: electronics / projects

author: dannyf
author_rank: Super Contributor
timestamp: February 06, 2014, 12:28:21 pm
content: In a separate thread, I suggested that it is possible to construct an inexpensive reference current source around mcus. I put one together on paper and it worked reasonably well but stability is a big issue.Here is the schematic of one implementation: the mcu outputs a pwm pulse train on R1/C1, with its output driving the mosfet. On the mosfet's source, a measurement resistor Rm1 is used to sample the current. R3 is the wire resistance. The mcu then adc's the voltage across Rm1 and use that to adjust the pwm duty cycle.So once a target is set, the output (current) will track to the target gradually, as shown by the traces.

author: Rerouter
author_rank: Super Contributor
timestamp: February 06, 2014, 12:36:17 pm
content: a micro-controller ADC is not the most accurate thing in the world, and you generally want an order of magnitude better specs to calibrate something,also your control algorithm on that looks quite bad (massive overshoot), instead try integrating only your readings and a proportional only control scheme as the capacitance is so large it dithering between 2 values should help you out,

author: dannyf
author_rank: Super Contributor
timestamp: February 06, 2014, 12:44:55 pm
content: While working on the stability, I came to the realization that this thing can be used as a voltage reference too: the voltage across Rm1 is maintained by the mcu.Here is an examle: R1/C1 is the lp filter, Q1 is the buffer, and RM1 is the measurement resistor. ROUT1, optional, isolates the high-impedance load from RM1.J2 outputs a voltage reference, and J1 (when not shorted) outputs a current reference.I have gotten the control algorihm stable across the full voltage band: 0-1.1v. The output current is determined by RM1 (in this case, 0 - 1.1ma).In the particular case, Iout is set to 40ua, and fluctuates from 39.9ua to 40.1ua (20x adc gain used here).Potential Improvements:1) make it dual channel: since the mcu has two pwm channels, we can replicate R1/C1/Q1/RM1/ROUT1 and we have another channel. One can be dedicated to volt and other current; or they have different ranges.2) improve resolution: the pwm duty cycle is being dithered to provide finer resolution. This creates fluctuation on the output. Another way is to utilize the unused tmr0 pwm channels OC0A and OC0B and add 8-bit resolution to the meter. Adding two resistors will do that.3) use external adc: the biggest draw back here is the onboard adc. A better adc could help.....The meter has a range of 0 - 1.1v (limited by the reference voltage). It has a current output of 1.1ma full-scale (RM1 = 1K), and current resolution of 0.05ua and voltage resolution of 0.05mv (RM1 = 1K and 20x adc gain).The meter has no UI and no calibration capability so it is entirely conceptual at this point. But it does suggest that something like this is doable.
Elector AVR Software Derined radio. - Page 1
Forum section: electronics / projects

author: geggi1
author_rank: Frequent Contributor
timestamp: January 07, 2016, 07:00:24 pm
content: In Elector 03, 04, 05, 06, 09, 10 in 2012 there was a project for the an AVR SDR radio.Is there anybody that know if it is possible to get the PCBs or gerber.
electret Mic preamp, how to improve design? - Page 1
Forum section: electronics / projects

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: January 04, 2022, 05:44:30 pm
content: I made this mic preamp for an electret mic, but it suffers from a bit of bias excursion when I bump the mic, I'm new to solid state electronics so how would I fix this? maybe by adding a resistor in series with the input coupling capacitor? so like a grid stopper - base stopper?other than that it sounds pretty good, just a little lacking in mid frequencies but I'm guessing that's just the cheap electret mic I used, should order those panasonic ones everyone's talking about...oh and testing the circuit in LTSpice it's not perfectly balanced on the outputs, I know that... I had the design of the circuit a bit different and decided to change it after I already made the circuit board... yes ik, very smartso now with the changes the outputs arent balanced, but I didnt care about that much since I'm just using it as a desk mic and dont care that much about some noise.. my room is noisier than any mic will be anywayso anyway, should I just add like a 10k resistor in series with the base? will that reduce the gain too? (without considering the voltage divider formed by the ..base leak resistor and the one I'll be putting in series)I attached the schematic of the circuit, and pictures if you're interested how it looks

author: bob91343
author_rank: Super Contributor
timestamp: January 04, 2022, 06:26:17 pm
content: What is bias excursion?
Electret micro  and lm 324 - Page 1
Forum section: electronics / projects

author: J4e8a16n
author_rank: Regular Contributor
timestamp: February 08, 2014, 08:06:41 pm
content: Hi,A) What is the the kind of the 4 opamps in a lm 324? LM386 or else?B) If I put the oscilloscope probe on the 100k resistor I read a 1.8 volt wave peak to peak.If I set a a LM386 as show on the attachment, I dont get a good result.JP

author: PA0PBZ
author_rank: Super Contributor
timestamp: February 08, 2014, 09:41:09 pm
content: LM324 is an opamp, LM386 is a power amplifier, totally different things.

author: dannyf
author_rank: Super Contributor
timestamp: February 08, 2014, 10:15:56 pm
content: LM386 is a power opamplifier. Fundamentally identical to LM324.Actually, most power amps are opamps.

author: J4e8a16n
author_rank: Regular Contributor
timestamp: February 08, 2014, 10:33:40 pm
content: Quote from: PA0PBZ on February 08, 2014, 09:41:09 pmI have red : " Many don't realize that the LM324 is two LM358 dual opamps." What are the two opamps in the LM358?Although the shema shows a second stage of amplifier....I have builded it and it works but Ihave to clap fiercely.I uploaded a new shema in my first post.I took the shema with the lm324 there

author: dannyf
author_rank: Super Contributor
timestamp: February 08, 2014, 10:38:33 pm
content: 1.8Vpp * upto 100x = ?QuoteWhat are or where are?

author: J4e8a16n
author_rank: Regular Contributor
timestamp: February 08, 2014, 10:48:08 pm
content: What are. Are they LM222 or else?

author: dannyf
author_rank: Super Contributor
timestamp: February 08, 2014, 11:05:00 pm
content: QuoteThey are two opamps for sure.QuoteWhy would you care? How would that information, if available, help you?

author: c4757p
author_rank: Super Contributor
timestamp: February 08, 2014, 11:45:52 pm
content: Quote from: J4e8a16n on February 08, 2014, 10:48:08 pmAFAIK there never was a single version of that particular circuit, they were always made in dual and quad. You could possibly find a similar single amp, but it's not going to bethe"original" single version of the LM358.Quote from: dannyfCuriosity? It doesn't actually kill cats, you know...

author: J4e8a16n
author_rank: Regular Contributor
timestamp: February 09, 2014, 12:07:11 am
content: Ok, ok.I am french canadian.Why does the circuit not produce a high output.
(Solved) Electret Microphone to uC - Page 1
Forum section: electronics / projects

author: kolbep
author_rank: Frequent Contributor
timestamp: July 19, 2019, 09:34:49 pm
content: Hi All,Another quick project I am working on,a (rough idea) dB Meter that logs to Thingspeak, or local server.My thought is to take a Electret Microphone -> Single Transistor Amplifier -> Esp8266 Analogue Input.I have used this schematic for inspiration :I am planning to use a Sonoff (ESP8266) for this, so I can easily pull 3.3v and Ground from it. But the Analogue Input is rated at 1v (for 1024)But, the amplifier circuit produces a positive/negative wave, which is centred around mid supply. which means when there is very little signal from the Mic (and through the amplifier), the reading from the ADC will be 512.Meaning (because the + and - swings of the signal are almost equal), I will only really have (1024-512 = 512) resolution.What I would like to do is : Set the Gain (using the feedback resistor) to a Peak-To-Peak Value of 2V,then throw away the -ve part of the signal, then shift the lowest part of the signal down to 0v.Because I am only worried about the Peak really, I do not need to worry too much about the missing bottom half.That way I will only have a positive signal coming into the uC, ranging from 0v (no signal) to 1v (as loud as it can get) for the full 1024 resolution)I have tried googling this, but my google-fu is failing me. or almost everybody does not want to throw away half the signal.Thanks once again for any assistance.

author: kolbep
author_rank: Frequent Contributor
timestamp: July 19, 2019, 09:40:54 pm
content: Never Mind,Just stumbled across a Peak Detector.That is the term I needed.
Electret Microphone - Page 1
Forum section: electronics / projects

author: cosmarchy
author_rank: Contributor
timestamp: March 11, 2020, 08:40:54 pm
content: Hello all,I have a couple of circuits which require 3-pin electret microphones:The trouble is that I cannot find any 3-pin varieties here in the uk.Does anyone know of a reliable source for these? What is the difference (apart from the obvious) between the 2 and 3 pin versions?

author: bob91343
author_rank: Super Contributor
timestamp: March 11, 2020, 09:10:24 pm
content: I think there is a discrepancy. An electret provides bias without a power supply. The circuits shown have a power supply, so they are probably not electret microphones, just ordinary condenser microphones that require power. Well, to be precise, not power but polarizing voltage.

author: floobydust
author_rank: Super Contributor
timestamp: March 11, 2020, 11:03:40 pm
content: Modern electret condenser mics are all two-wire, ground and signal. You could use one in your circuit, just short the tip+ring connection together. They have combined power and signal to save a wire.I think R1 is too low for a 9V feed, it is typically 10k-22k. The JFET in the mic is typically a 2SK596S with IDSS average 0.16mA if anyone wants to do math.You might need an extra RC filter for the mic power feed, any audio ripple on the 9V rail can get into the mic circuit and cause oscillations/feedback. Worse with battery power.edit: standard operating voltage is 2-3V for these mics, and you'd have to check the IDSS spec of the mic to get the best resistor value. It is not critical but the Internet is full of copycat errors.TI Electret Microphone Pre-Amplifier Reference Designuses 2V for 13.7k at 9VCUI micsspecs 3V at 0.5mA max.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 11, 2020, 11:33:50 pm
content: A 3 wire microphone allows adjustment of sensitivity.https://sound-au.com/project93.htm

author: cosmarchy
author_rank: Contributor
timestamp: March 12, 2020, 08:16:15 pm
content: Thanks very much for your help guys, verymuch appreciated

author: Buriedcode
author_rank: Super Contributor
timestamp: March 13, 2020, 04:18:45 pm
content: You can usually (but no always!) convert a 2 pin electret to 3 pin with a slight modification - called the "Linkwitz mod" but I'm sure others have done it before. NiHaoMikes link provides all the details.I've found the 3 pin ones to have lower sensitivity, but also more linear. As for noise, theres a great deal of variation, as there are so many cheap electret capsules, even some of the cheapest can be remarkably good.

author: ploegmma
author_rank: Newbie
timestamp: June 05, 2020, 07:49:38 pm
content: Maybe just use a two pin electret? If you're looking for a circuit, perhaps something like this:https://hackaday.io/project/171404-microphone-the-dumbbellmic
Electric Bike Hub Motors (E-bike Brushless BLDC Motors) - Page 1
Forum section: electronics / projects

author: David
author_rank: Frequent Contributor
timestamp: January 06, 2015, 08:48:06 pm
content: Hi all,Very long time since I've posted on here!I'm currently working on an Inverter design for a brushless hub motor, commonly used on E-bikes. However, I am struggling to find any technical information on the motors in terms of winding inductance/resistance, no. of pole pairs, if they are wye or delta wound etc.. Now I appreciate that the following question is along the lines of how long is a piece of string but I am wondering if anyone has any such information or owns one of these? I suspect they are all fairly similar (cheap chinese) ultimately. What I am mainly interested in is the winding inductance as I read <150uH on one website which sounds very low and will completely change the inverter topology I would go for.Hopefully I will have one on order in the near future so I can take some measurements but in the mean time any help would be greatly appreciated.This is the sort of thing I'm on about:http://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-electric-hub-motor-kit/20-inch-48v-1000w-electric-bike-kit-front-wheel-591.htmlCheers,Dave

author: CM800
author_rank: Frequent Contributor
timestamp: January 06, 2015, 09:50:35 pm
content: I wouldn't buy any motor unless they can provide a full datasheet. Ask them for one, if they can't provide one with all information then find another company or get a proper BLDC motor and use a chain on it.

author: David
author_rank: Frequent Contributor
timestamp: January 06, 2015, 10:09:15 pm
content: Quote from: TCWilliamson on January 06, 2015, 09:50:35 pmAgreed. Awaiting a response as we speak. Although I only have contact with the Chinese distributor so could be interesting...

author: max_torque
author_rank: Super Contributor
timestamp: January 07, 2015, 12:03:44 am
content: I assume you know about this site:http://endless-sphere.com/forums/Lots of good info on there!

author: chickenHeadKnob
author_rank: Super Contributor
timestamp: January 07, 2015, 09:43:46 am
content: yes! go to endless-sphere and educate your-self in the motor portion of the forum. Justin from ebikes.ca/ grin technology has written an on-line ebike simulator here:http://www.ebikes.ca/tools/simulator.htmlIt doesn't have anywhere near the total number motors available from china, but even with those in the table you can get an idea of the variety. Many different windings KV ect. Good luck, lots of reading ahead.
Electric car battery upgrade - Page 1
Forum section: electronics / projects

author: tesla500
author_rank: Regular Contributor
timestamp: July 03, 2011, 11:34:50 pm
content: I'm installing new batteries in my electric car, so I though I'd make some videos.This is a converted Pontiac Firefly which I did about 5 years ago with a friend. It used to have 120V of 78Ah lead acid batteries. The old batteries were about 5 years old and in need of replacement, so I though I'd get some lithium ion batteries (144V 60Ah) instead of lead acid, to greatly increase the range and reduce the weight. The old batteries weighed 250kg, the new ones weigh 100kg and have about twice the energy storage.Even though the Ah rating of the lead acid is higher than the lithium ion, the full capacity of lead is only achievable with lower discharge currents, the effective capacity goes way down with high discharge currents seen in an EV. Lithium keeps its capacity at much higher discharge currents. In this car, I was getting only about 30-35Ah real world out of the lead acid, while the lithium should maintain near its full 60Ah capacity.I also had to modify the motor controller and DC-DC converter to work on the new 144V battery, they were 120V rated parts. Luckily there's enough margin in the design to handle the higher voltage.Stay tuned, more videos are on the way too.Controller/DC-DC ModsBatteries and BusbarsCell board installation/wiringRegards,David
Electric conductor/connector with high thermal insulation  - Page 1
Forum section: electronics / projects

author: dindondee
author_rank: Contributor
timestamp: January 08, 2024, 05:25:01 am
content: Hey there, hope you're well. I used nichrome wire to build a heating element that heats up to 450F-600F. Silicone wire is used to supply electricity, however the silicone wire heats up after extended use since it's connected to the heating element. The element termination leads were twisted to increase resistance and prevent heating before being connected to the wire. I am not comfortable with the silicone wire getting hot since it connects to a PCB.Can you please recommend a material (electrically conductive but thermally insulating) that can go between the leads of the heating element and the silicone wire? I'm currently thinking of impregnating resin with graphite or silver that will be casted to form a connection between the heating element and silicone wire. This is to make the resin conductive and reduce the heat transfer to the wire from the heating element leads, but I'm not sure if that'll work. Any other ideas or suggestion would be greatly appreciated, thank you.

author: Someone
author_rank: Super Contributor
timestamp: January 08, 2024, 06:05:45 am
content: One typical solution is to crimp/spring-fit lengths of metal ribbon from the heating wire to the supply wiring. Thin enough to warm up a little from I2R, while not conducting too much from the heater.

author: perdrix
author_rank: Frequent Contributor
timestamp: January 08, 2024, 06:31:33 am
content: Strip back the silicone insulation and use fibre-glass sleeving to insulate the portion that has been stripped.That will tolerate the temperatures very wellDavid

author: Psi
author_rank: Super Contributor
timestamp: January 08, 2024, 07:35:49 am
content: When looking with a thermal cam I was surprised how much heat was escaping my device case over the 18AWG wires from the 24P (ATX style connector) that I was using.(Device was doing 12V 10A 100Hz PWM)

author: MarkT
author_rank: Frequent Contributor
timestamp: January 09, 2024, 10:51:38 am
content: Quote from: dindondee on January 08, 2024, 05:25:01 amDifficult, free electrons carry heat efficienly as well as charge, being free and all. Glass fibre sleeving is the standard time-proven approach, used in every appliance with a heater...

author: Wolfram
author_rank: Frequent Contributor
timestamp: January 09, 2024, 10:56:33 am
content: It's also possible to heatsink the interconnection itself, by using an interconnection with a large surface area, or using a thermal insulator like a ceramic to transfer the heat from the electrical connection. Something as simple as a ceramic terminal block could be worth a try. This can be combined with the suggestion of using glass fiber sleeved wire. It might also be beneficial to reduce the wire cross section, there will be an optimal value. Too thin and it will heat up from the current it's carrying, too thick and it will transfer more heat from the nichrome element interconnection.
Electric hand warmers - Page 1
Forum section: electronics / projects

author: antenna
author_rank: Frequent Contributor
timestamp: November 11, 2022, 04:59:44 pm
content: I have been looking at rechargable hand warmers online but I am curious if they are safe. I thought lithium ion batteries did not do well in hot enviroments. Are these things safe to use or will they choose a random day to burn the house down?

author: james_s
author_rank: Super Contributor
timestamp: November 11, 2022, 06:53:37 pm
content: Safety depends on how the specific product is designed. I doubt the heat is a problem, the battery is likely on the cuff or back of the hand, not inside the glove, and it's not going to be scorching hot. It is certainly possible to design one that is safe, the biggest risk is always the charging system. A poorly designed charger that overcharges the battery can start a fire.

author: bidrohini
author_rank: Regular Contributor
timestamp: November 12, 2022, 05:04:39 pm
content: You may find some more information at the following links:https://www.consumer.org.hk/en/press-release/20110114-2https://www.ocoopa.com/blogs/ocoopa/how-to-safe-use-usb-hand-warmer

author: antenna
author_rank: Frequent Contributor
timestamp: November 13, 2022, 05:33:51 pm
content: I ended up going with a liquid fuel warmer. Thanks

author: james_s
author_rank: Super Contributor
timestamp: November 13, 2022, 07:47:20 pm
content: Liquid fuel is certainly more dangerous than electric, but if used properly either is unlikely to cause a problem.

author: richnormand
author_rank: Unknown
timestamp: November 14, 2022, 09:49:26 pm
content: No safety issues from my perspective on lithium batteries used for heated gloves.I have these:https://www.motionheat.ca/Initially made for oil workers in northern Alberta. They had to be rugged, wear resistant and last the whole shift.Used for ski and using the snowblower in -35C temperatures. Great in the car without a heated steering wheel on those mornings too.The battery is in a small pouch at the glove entrance where there is no heating so it does not get warm.For ski I got the wire harness the goes through the coat sleaves to a pocket inside so I am not disturbed by the weight at my hands/wrists while in motion.They are in their fourth or fifth year and the lithium batteries are still up to the job.They still last about 6 hours on the mid setting.
Electric Nose - Page 1
Forum section: electronics / projects

author: HooRide
author_rank: Regular Contributor
timestamp: March 13, 2013, 11:23:13 pm
content: So I've been doing some research (mostly for fun) and came across this:http://en.wikipedia.org/wiki/Electronic_noseWhat I haven't been able to find is a source for any of the sensors; I guess I would want to start with one of the MOSFETs.Anyone ever play around with electronic noses or know where one can buy the sensors?
Electric Scooters - Page 1
Forum section: electronics / projects

author: indago
author_rank: Newbie
timestamp: May 21, 2014, 11:36:31 am
content: On the eMoto G2 electric scooter, I noticed that when the key switch is turned on, the head light and tail light are turned on. The head light switch is inoperable, and is not wired into any circuiting, although the operators manual shows that there are three positions for the head light switch: to the right is off; center is the running light, instrument light, tail light; and to the full left, all the lights are on with the head light. The head light can't be turned off while operating the scooter in the daylight hours.I would like to revise this, and wire the light switch into the controller, where there must be some device that controls the lighting, so that the lighting system will work like it is supposed to. Does anyone here have a schematic for the controller board for the G2, or know where I could obtain one?
Electric toothbrush inductive charging limits - Page 1
Forum section: electronics / projects

author: e100
author_rank: Frequent Contributor
timestamp: February 14, 2025, 07:09:50 am
content: What are the practical power limts for what is presumably a transformer with a large air gap between inner and outer coils.I'm thinking about how this could be adapted for use with outdoor gadgets to avoid the ubiquitous leaky openings that allow moisture to get in and ruin the electronics inside. The established mobile phone wireless charging standards such as Qi have a rather large coil that is too big for something like a bike light. I have some old electric toothbrushes with dead batteries that could in theory be disassembled and repurposed as mini wireless power supplies for use inside gadgets.

author: Chalcogenide
author_rank: Regular Contributor
timestamp: February 14, 2025, 09:27:35 am
content: I had some luck in the past with these kinds of "micro" coil wireless power transfer boardshttps://it.aliexpress.com/item/1005005221322325.htmlIt is a bit finicky in that, in my experience, you need to "orient" the two coils correctly to get the highest power transfer, but it works surprisingly well for the size and can directly charge a lithium battery.
Electric Vehicle Isometer - Page 1
Forum section: electronics / projects

author: sanwal209
author_rank: Regular Contributor
timestamp: January 09, 2018, 02:37:53 pm
content: Hi Folks,We are currently using isometer from Bender which is as follow:https://www.bender.org/documents/IR155-03-04_datasheet_NAE1012830.pdfI want to develop our own Isolation meter but i couldn't find any reference or documents for initial guidance. If anybody worked on such kind of project then please share some documents or at least basic working principle of isolation meter.PS: We are using isometer to measure the isolation between high voltage battery pack terminal and chassis ground.Any help would be greatly appreciatedThanks

author: capt bullshot
author_rank: Super Contributor
timestamp: January 10, 2018, 09:00:40 am
content: The basic working priciple can be guessed from that datasheet:The isometer applies a testing voltage (+40V / -40V alternatively) to the isolated circuit and measures the current (or vice versa). The test voltage is applied through a rather high impedance. So in case of a full earth fault the current is limited to a safe (a few mA) level.All the rest is more or less sophisticated software that does some correlation and averaging of the results to handle the apacitance (the data sheet states 1uF is allowed, this must be charged / discharged while measuring) and filter high frequency components caused by the inverters.The Bender PCB looks quite complex, I guess that is caused by all the real world problems that your device must handle then. The basic priciple is rather simple I guess.

author: oldway
author_rank: Super Contributor
timestamp: January 10, 2018, 11:18:40 am
content: Unless you are in the field, I advise you to not develop your own isometer because it is a device that can affect safety and therefore engage your responsibility or that of your firm in case of accident.In addition, one must know the standards and regulations that apply if any.For industrial battery chargers with ungrounded batteries, an insulation ground fault signaling (considered as non-essential, for information only) was made in a very simple way with some resistors, a 24V reed relay and a zener diode .The reed relay contact was controlling an insulating ground fault signal lamp.

author: sanwal209
author_rank: Regular Contributor
timestamp: January 10, 2018, 02:31:13 pm
content: So i have two choices either to build the isometer based on discrete components or based on COTS SoC i.ehttp://www.sendyne.com/Datasheets/Sendyne%20SIM100%20IC%20Datasheet%20V0.4.pdfAs oldway said it will be too risky to build our own Isometer due to its impact on safety. I would choose SIM100 SoC instead of discrete components.PS: I found three methods which are as follow:1. BUS end voltage2. AC Signal Injection3. DC Voltage insulation measurement@Capt bullshot the method you are talking about is AC signal injection.These are actually quite interesting theories.
Electrical etching concept...what is it? - Page 1
Forum section: electronics / projects

author: sean87
author_rank: Regular Contributor
timestamp: May 14, 2013, 10:33:14 pm
content: Hi guys,I want to make my own electro etching to make marks and logos on metal stuff.I have seen some commercial products, but I can not afford to buySo I want to create my own. Can someone pleae tell me the logic, and what would I need?I have seen they use AC first then DC...can't it be done with DC only? I have also seen some videos on youtube people do it with a 9V DC wall adapter....but commercial products are for example 20 volt 10 amps...eny explanation?A commercial one is here:http://www.etch-o-matic.com/knifemaker.htmThanks!

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 15, 2013, 01:20:11 am
content: Look up EDM.

author: Fuse_Burner
author_rank: Contributor
timestamp: May 16, 2013, 02:14:03 am
content: I don't think he's talking about edm, I think he's talking about electro chem etch.I'd say that's a very reasonable price for the machine, solution and stencil paper.

author: SeanB
author_rank: Super Contributor
timestamp: May 16, 2013, 05:51:21 am
content: Chemical etching is easy, you just need a carbon pad, a stencil and a conductive electrolyte, either KOH or Naoh, NaCl or even acetic acid, and a power source. Works well on most metals except aluminium, where you will need the KOH to strip the anodising off it.

author: smashedProton
author_rank: Frequent Contributor
timestamp: May 16, 2013, 09:04:51 pm
content: Look up electrochemisty its not too hard.
Electrical isolation issue (DAC) - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: September 02, 2019, 06:34:33 pm
content: So I have been using a DAC/Pre-amp/Headphone amp for a while now and it started acting up by glitching/stuttering the audio output and I've been bashingmy head against a wall trying pretty much all the possible combinations of connection type, computers, power supplies etc. to arrive to the conclusion thatthe the power supply seems to be the issue.It only works fine when powering it up from a dedicated pure sine wave inverter but unfortunately said inverter is loud and a lot of clutter to my computer setup which I don't like.Could an isolation transformer solve my issue as it completely separates the physical wired connection from other devices in my room sharing the same power?If not, what would be the alternative and why do you think this is happening? I even disconnected the ground wire from the chassis internally but the issue remained

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: September 03, 2019, 07:40:22 am
content: Quote from: blueskull on September 03, 2019, 05:37:35 amYou mean a sine wave inverter?That wouldn't work since the device is mains powered with a toroidal transformer inside it so I cannot source it with any DC power.
Electrical over current protection - Page 1
Forum section: electronics / projects

author: tan98010
author_rank: Contributor
timestamp: May 16, 2014, 03:18:35 am
content: Guys, why do i need to install an electronic overload relays on the magnetic contactor? since i already install the MCB(miniature circuit breaker) with the appropriate current rating, based on my knowledge the MCB will trip during the during the over current.

author: SeanB
author_rank: Super Contributor
timestamp: May 16, 2014, 04:30:36 am
content: MCB is rated to trip to protect the wiring, not the motor. The motor overload is meant to trip when the motor exceeds the rated current. Just using the MCB means that the motor has to draw enough overcurrent for long enough to exceed the wiring rating, which typically means that by the time it trips the motor will be well cooked. the motor overload means that if say the motor is overloaded and slows down and draws excess current it will shut it off. Remove the overload and reset and it will run again.

author: tan98010
author_rank: Contributor
timestamp: May 16, 2014, 05:16:25 am
content: Thanks, thats help alot.
Electrical stats display - Page 1
Forum section: electronics / projects

author: Phobos0001
author_rank: Newbie
timestamp: November 15, 2018, 07:20:40 am
content: Hi Everyone,I just found this site today and I'm hoping for some advice for a little project for the workshop here.I do some work on industrial components such as motors, gearboxes, Vector&Frequency drives and the like, and I like to monitor various parameters after I reassemble for no-load bench testing,now I have the usual hand held testing tools like the good ol' multimeter & clampmeter but I'm hoping to do a hardwired setup on the wall.Im hoping to have a display(s) that I can check phase to phase voltage voltage and current draw on each individual phase, any other features are just icing on the cake.This corner of the shop is on it's own breaker, I have a 415V/50Hz (nominally speaking because south Australia) power supply, currently I only have a 32A breaker installed but this can handle a 60A continuious draw for running induction motors upto about 30Kwhas anyone got some suggestions on some meters, DIN, Panel, it doesnt matter how they mount, I have no space constrictions and I'm not shy about fabrication.My restriction is as with most people, budget. I dont want to be spending six grand on the world's most accurate high sample rate machine. but the idea of these $20-50 dollar meters from ebay or china scare me, this is not exactly a 10A supply from a house we're talking about here.I hope this covers it all, feel free to ask if you guys need more infoand thanks in advance for any assistance

author: station240
author_rank: Unknown
timestamp: November 15, 2018, 08:54:30 am
content: Schneider Electric, ABB and others, make things called a "Digital Power Meter"https://au.rs-online.com/web/c/automation-control-gear/panel-meters-components/digital-power-meters/Of course you still need to buy the separate Current Transformers to suit the meter and your application.Probably cheaper to get some of this stuff from an Electrical Supply shop, or used on ebay.

author: Phobos0001
author_rank: Newbie
timestamp: November 18, 2018, 09:47:24 pm
content: Hi Station, sorry for the late reply,it's been a mental week!I've started going through the data sheets for these digital power meters,looks like they will do everything I want and then some.I'm thinking one of these....https://au.rs-online.com/web/p/digital-power-meters/9145281/and, if I have done my homework correctly,three of thesehttps://au.rs-online.com/web/p/current-transformers/1718765/unless I'm missing something else, I should get away with around $300 after I get some cable & terminations.I still have plenty more reading to do so I can make sure everything will work properly before I pull the trigger on a purchasecheers for the help
Electrically conductive thermal pads. - Page 1
Forum section: electronics / projects

author: paul8f
author_rank: Regular Contributor
timestamp: February 02, 2021, 11:27:07 am
content: Hi all,couldn't figure out why a device was functioning fine, but was drawing more p/s current, and was working a little hotter than it should have been.Turns out an electrically conductive thermal pad was used on the bank of TO-220 tabs, instead of insulating thermal pads. The pad had a measured resistance per inch of a few kOhm.So my question is.... what scenario or what type of products call for a conductive (or semi-conductive) thermal pad like this? I knew these pads existed, but never encountered them before. Maybe the pad in question might be good for ESD purposes allowing a slow drain to gnd??!

author: penfold
author_rank: Frequent Contributor
timestamp: February 02, 2021, 12:35:45 pm
content: The non-electrically isolating gap pads can have much better thermal performance and can get away with being much thinner etc so are useful when you already have electrical isolation via the package, something like that fully encapsulated TO-220 variant I can't remember the name of or one where the IC is bonded to an aluminium oxide insulator like most IGBT modules tend to be, or even microcontrollers/processors and misc ICs etcThere is a variety of silicone based pad (I think) made by Bergquist/Henkel, intended for both electrical and thermal conductivity, the performance of both relies on pretty high mechanical pressures so it wouldn't measure particularly well when not compressed.

author: paul8f
author_rank: Regular Contributor
timestamp: February 03, 2021, 11:03:46 am
content: I think you just hit the nail on the head with your answer there!The pad material was a lot thinner than the usual stuff, and when combined with high pressure mechanical fixing, I can see how thermal performance would be much higher.Electrical isolation via the packages would be one scenario. I suppose another scenario would be where all TO-220 devices in the bank were identical (e.g. all were transistors using their tabs as common collectors). All collectors would be bolted to a stand-alone heatsink (or cooling aggregate), so any parallel resistance (due to the conductive thermal pad) between the transistor tabs could be ignored? The conductive pad in this case might be a wise substitute for messy thermal-paste??