hybridfree/eevblog-posts huggingface dataset:
Mutli cable anyone? - Page 1
Forum section: electronics / projects

author: onkartmjanger
author_rank: Newbie
timestamp: August 20, 2016, 10:49:54 pm
content: I am struggling in the part jungle... Not a native English speaker and searching for parts. Looking for a multi cable, pre-tinned, 2.54mm pitch like this one:http://www.mouser.com/ds/2/35/11001-fusion-bonded-cable-jumpers-337380.pdfBut this is the only manufacturer I can find.Anyone out there that can point me to another supplier of cables like this?

author: viperidae
author_rank: Frequent Contributor
timestamp: August 21, 2016, 01:09:09 am
content: try searching for "ribbon cable"

author: ovnr
author_rank: Frequent Contributor
timestamp: August 21, 2016, 02:23:27 am
content: 2.54mm pitch ribbon is entirely outdated, buthere you go.(tl;dr on ordering from Digikey when you're in Norway: Free shipping above 525 NOK, all prices w/o VAT, if you pay in NOK or EUR you get it shipped DDP which means no customs fees at all. You get a bill from UPS for the VAT - and only the VAT - a couple weeks later.)

author: onkartmjanger
author_rank: Newbie
timestamp: August 21, 2016, 09:07:12 am
content: thanks, but I am looking for the pre-cut/pre-tinned cables. Not a roll. Alternative to using connectors and cables with connectors..

author: bicc1306
author_rank: Contributor
timestamp: September 29, 2016, 12:19:43 pm
content: Try to find your cable here.http://eu.mouser.com/Wire-Cable/Flat-Cables/_/N-5ggm
Mutual inductance in BLDC motor in the DQ reference frame question - Page 1
Forum section: electronics / projects

author: Etesla
author_rank: Regular Contributor
timestamp: June 06, 2024, 10:41:39 pm
content: Hi all,I'm trying to understand what a schematic would look like capturing the terms Matlab has documented here:https://www.mathworks.com/help/sps/ref/pmsm.htmlI'm going from simple to complex. Starting simple now.My first question is the following.The matlab documentation states:Ld = Ls + Ms - 3/2 LmLet's pretend it's a non salient motor and Lm = 0. Lets just worry about the locked rotor nothing is moving case.In that case there seems to be an Ls and Ms that I have to worry about. I'm assuming Ms exists because there is a transformer like coupling between the stator windings, is that true?If I set up an LTSpice model to inject a voltage vector with any magnitude and angle into a three phase motor model in a stepped voltage transient case, with no coupling between the motor coils, I see that my calculated Id rises as my Id voltage steps. I can also see that my 'Ld' and 'Rd' that model this correctly have equivalent values to the per coil inductance and resistance to a Y wound motor model. I'm assuming this is represented by a Ls = 40u, Ms = 0, Lm = 0, Rs = 10m case:From the equation, I would assume that Ld would increase as the coupling between the coils increases, because Ms would become a positive nonzero number, Ls would stay the same, and Lm would still be zero. So Ld would increase. However if I add coupling between the three coils:Then I observe that the calculated Id increases faster for the same Vd. To me that indicates that Ld decreased when I increased the coupling, instead of increasing.What's incorrect about the ideas in my LTSpice model? Does Ms not come from a transformer like coupling between the stator windings? How would a person measure Ls and Ms experimentally when handed a black box motor with three terminals?LTSpice model is attached.
Mux selector - Page 1
Forum section: electronics / projects

author: JohnnyP
author_rank: Regular Contributor
timestamp: February 01, 2015, 08:36:19 am
content: I'm adding a MUX control switch so I can select one, the other, or alternate between them using a clock.I used M squared logic and came up with this. I think it will work, but does any one have a better way to do it?A' is the clock.The switch is an ON-NONE-ON three position switch.

author: voja
author_rank: Contributor
timestamp: February 01, 2015, 09:03:58 am
content: Why do you need OR gate here? 1K is much less than 10K, so OR gate inputs are practically shorted, and it works like the simple buffer.

author: JohnnyP
author_rank: Regular Contributor
timestamp: February 01, 2015, 09:21:39 am
content: Without the OR gate you will get about 0.45v ripple. Not enough to affect the control pin of the MUX but it looks bad.I guess it doesn't matter, but I will test it on a plug board to see which way I like it.Correction, the switch should be an ON-OFF-ON.

author: voja
author_rank: Contributor
timestamp: February 01, 2015, 09:45:15 am
content: If you care how it looks, why do you use MM logic?OR gate + resistor will help avoiding 0.45V with high level on pin 1, but not with low level, as the clock signal on pin 2 (with 0.45V low level) will decide the output signal. To do the full (unnecessary) job, you will have to employ the much more complex MM circuit, or the simple schmitt trigger buffer instead of OR gate.

author: JohnnyP
author_rank: Regular Contributor
timestamp: February 01, 2015, 09:58:46 am
content: Thank you so much, good explanation. Don Lancaster would approve.

author: voja
author_rank: Contributor
timestamp: February 01, 2015, 10:24:58 am
content: Another thing, I guess that you used 1K resistor for ESD protection, but it does not protect input 1, only input 2. It would be even better if you used buffer and put 1K for protection.

author: JohnnyP
author_rank: Regular Contributor
timestamp: February 01, 2015, 08:20:36 pm
content: Found a dual Schmidt buffer
MWO platter motor direction control - Page 1
Forum section: electronics / projects

author: alah
author_rank: Contributor
timestamp: November 27, 2017, 07:49:22 pm
content: HI, ALL. I hope this post is not repeated, having problems with internet.I want my motor to always start in the same direction; I tried with a capacitor without luck.Is it possible? Thanks, Alberto.

author: james_s
author_rank: Super Contributor
timestamp: November 30, 2017, 12:25:28 am
content: What is an NWO platter?If the direction is random without the wiring changing then that sounds like a synchronous motor. These typically use a mechanical ratchet-like mechanism to prevent starting in the wrong direction.

author: mark03
author_rank: Frequent Contributor
timestamp: November 30, 2017, 01:25:20 am
content: I assume MWO = microwave oven. I always wondered why the platter in mine rotates in a random direction.

author: james_s
author_rank: Super Contributor
timestamp: November 30, 2017, 01:53:25 am
content: Ah, yes those use synchronous motors, at least the ones I've taken apart do. If there is nothing mechanical to prevent them from going one way or the other then the direction of rotation will be random depending on the position of the rotor when power is applied. If you stall one it will usually reverse which is how the little ratchet mechanism works.

author: amyk
author_rank: Super Contributor
timestamp: November 30, 2017, 03:08:03 am
content: I've seen mention of controllers for bidirectional single-phase synchronous motors of the type described here, which can always start them in a controlled direction by sensing the back EMF and adjusting the waveform appropriately.

author: james_s
author_rank: Super Contributor
timestamp: December 01, 2017, 01:52:34 am
content: It would be interesting to see a design for one of those, although I can't help but wonder what the motivation is in making the turntable always turn the same direction, beyond satisfying one's OCD tendencies. It would probably be easier to replace the motor with a different type.

author: alah
author_rank: Contributor
timestamp: March 07, 2018, 05:09:39 pm
content: Im not using it for the platter; it turns apalancawhich activates contacts as a mechanical relay. I managed to modify my arduino code to solve this problem, anyway. THANKS for answering.
mx88v430ucg datasheet???????????? - Page 1
Forum section: electronics / projects

author: diehard67
author_rank: Newbie
timestamp: November 05, 2013, 01:42:14 am
content: I have a mx88v430ucg on the board from a dead digital picture frame, I think this chip is some kinda display controller as it connected between the grid of balls where the cpu used to be and the connecter where the lcd connects.does anybody know where I can get a datasheet or at-least the pinout for this thing, I would like to see if I could use it to make something useful from the lcd panel.all the parts I have to work with are junk box stuff from old dead electronics, a rather large box of dead electronics lol.
My 1000th posing on the Forum - what a journey - Page 1
Forum section: electronics / projects

author: enut11
author_rank: Super Contributor
timestamp: August 01, 2024, 07:54:03 am
content: My 1000th posting on the EEVblog Forum. What a journey.I first joined in October 2015 so that means an average of about one posting every 3 days. Hmmm…I continue to read through the various sections in the Forum most days, contribute some ideas of my own and I have learned a lot in return. What strikes me is the friendly nature of the members and the wealth of knowledge they bring to the discussions, often helping others through difficult projects or repairs. This is also a testament to founder DJ and to the quality of the members he has attracted to the Forum.Listed below is a compilation of projects that have come about as a result of my association with the Forum over the last 9 years. Even so, it is not able to convey the wealth of knowledge gained by being an active member. Thanks to everyone who contributed and helped me along the way.My DIY projects:Electronic Loads (150W and 300W)30v/1A Power supply – based on red Chinese PCB30v/1A Power Supply – based on green Chinese PCBCapacitance Bridge by Conrad HoffmanDC Null Meter by Conrad Hoffman4 Wire Precision Resistor Reference boxResistor Tempco OvenKVD based on Fluke 803 meter parts0-100v AC Voltage Calibrator10v DC Voltage Calibrators – LM399DC Voltage Calibrator – LTZ1000High stability 100vDC referencePrecision Wheatstone BridgeCurrent Shunt CalibratorBudget GPSDO designed by MIS42N5 transistor ESR meter by jdiddyJust to name a few. There were also lots of smaller projects.I still look forward most days to finding out what’s new…enut11(an electronics nut from wayback…)

author: RoGeorge
author_rank: Super Contributor
timestamp: August 01, 2024, 07:59:15 am
content: Quote from: enut11 on August 01, 2024, 07:54:03 am

author: Gyro
author_rank: Super Contributor
timestamp: August 01, 2024, 08:57:15 am
content: Congratulations enut. That's a nice list of projects, I like the bias towards Metrology stuff too, that's where the real savings come about versus trying to buy something.As an added reward, you also get to see the super exciting stuff that happens in the Supporters Lounge!

author: pcprogrammer
author_rank: Super Contributor
timestamp: August 01, 2024, 11:33:07 am
content: Quote from: Gyro on August 01, 2024, 08:57:15 amYeah you can't really live without that access anymore
My 10MHz distribution amplifier - Page 1
Forum section: electronics / projects

author: thinkfat
author_rank: Unknown
timestamp: January 10, 2021, 10:28:58 am
content: While spiraling down the path into time-nuts territory, I realized that I need a way to distribute 10MHz somehow. Not willing to hunt for a video distribution amplifier on ebay, I dug out an old design from W.H. Rech (DF9IC), a friend kindly shared a hardcopy of the orignal schematic (drafted on paper, Dave-CAD style!).I captured the schematic into a KiCAD project, which you can find here:https://github.com/thinkfat/dist-ampThe PCB is 4 layer, layed out rather generously in 100mm by 63.5mm, with footprints for SMA jacks.Power input is 12V through a barrel connector (5.5mm/2.1mm).I've attached some measurements done with a NanoVNA V2plus4.If you want to recreate it, there are Gerber and drill files and also SMT CPL+BOM for JLCPCB SMT service. It includes most of the passive components save two inductors for the input filter and the amplifier chip (MAX4022ESD+).
my 2000Amp IGBT module - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: September 30, 2024, 04:49:53 pm
content: i think this is one of the biggest i have seen,are they cheating a little bit ? it is 4 x 500A and again,each section is made of quite a lot of single transistors.. 28 transistors and 12 diodes, in each module.all detail here, i made a little video :https://youtu.be/9oXXApHc3VY

author: jbb
author_rank: Super Contributor
timestamp: September 30, 2024, 08:26:59 pm
content: For a larger power module (above 150 A or so) it’s normal to put several IGBT and diode chips in parallel. The ceramic PCB (and bond wires) should be carefully designed to balance the conduction and switching losses.

author: Randy222
author_rank: Frequent Contributor
timestamp: September 30, 2024, 08:45:33 pm
content: What if the silicon components don't all turn on or turn off all at the exact same time?They can make a single big diode that can do 200 300 500 amps. Can't they make a IGBT or FET big enough to handle 5000A?

author: langwadt
author_rank: Super Contributor
timestamp: September 30, 2024, 08:53:41 pm
content: Quote from: Randy222 on September 30, 2024, 08:45:33 pmare there actually any big single diodes like that or are they really just a buck of smaller diodes in parallel in the same package?

author: jbb
author_rank: Super Contributor
timestamp: September 30, 2024, 09:48:34 pm
content: I’m not sure about the 100 A region, but for very large ratings there are indeed some giant monolithic devices available.They tend to be packaged in round ceramic ‘hockey puck’ packages. Available devices include diodes, SCRs/thyristors, GTOs (Gate Turn Off thyristor) and IGCTs (Integrated Gate Control Thyristors).Rambling a bit:GTOs and IGCTs can be turned off and are hence suitable for PWM-like operation. However, at the device sizes in question - thousands of Volts and thousands of Amps - the switching losses are huge; I’ve seen data sheets where the relevant graph is labeled inJoules(as opposed to micro Joules for lesser switches). Therefore switching frequencies are limited to a few hundred Hz and control techniques like Optimal Pulse Patterns (OPP) come into play because the offer better Total Harmonic Distortion (THD) performance than PWM for the same switching losses.
My adventure with Dyson battery - Page 1
Forum section: electronics / projects

author: najrao
author_rank: Regular Contributor
timestamp: June 24, 2024, 01:25:08 pm
content: Picked up a Dyson, probably V6 or 7 or 8, more or less complete, with battery blinkingblue! Tested with another battery and the motor works.Not having the correct charger, I used my bench supply to charge at 0.5A. Not a sin this, have done it before. Whatwasmy sin was: fed the juice at the power socket, and not at the charging one. This still charges even orange blinkers, through the mosfet body diode.Stopping the charge at 25.2V, for the six cells, I found to my horror that the blue blinker, which should have gone steady, had turned orange. The 32 flashes told me the BMS has locked out, sine die. I had killed a good battery!I drilled 3mm holes, six on either side, to probe each cell's voltage. There was a fair bit of unbalance, two at 4.0 and others 4.2-3. The BMS just did what it was designed to do.Now there are excellent hi-tech solutions in our forum to salvage Dyson batteries, but, alas, my education was sadly neglected then for me to apply them now. I needed simpler.Much spudger work revealed the innards, and I manually balance-dis-charged to 4.0 each cell. Resting for 4 hours increased the remaining unbalance slightly, but then stabilized. The cells are all good! The orange blink however continued unabated.So I decided to do it my way:1. Use the dead BMSonlyto operate the trigger switch, and turn on the power mosfet as required.2. Reinstate the charging socket which is locked out.3. Wire up to a 7-way plug to connect to my Imax B6 clone charger so you can be sure the cellsstaybalanced.1. gets complicated by the need to provide a somewhat fast drive not dependent on the action of the trigger microswitch, limiting the gate voltage to 12V, and still make sure there will always be enough. The mosfet is low threshold, but the BMS supplied about 10V normally. It is now permanently set to pull the gate down, but fortunately through a 1k8 resistor. I use this as the lower of a divider from the total battery voltage of 21.6V. A12V zener is still needed.To prevent discharging the battery too far, I have devised a simple low voltage lockout set to 20.5V. This doesnotlook at each cell separately, but then there will be frequent balancing in service. The gate drive is fed through a PUT with its anode gate held at 20.8V by a zener.The 30A fuse on the board is still good.2. was just shorting the SOT control transistor, emitter to collector. An existing Shottky was retained, so cannot discharge backwards.3. is awfully tricky, no space inside, and you are soldering to a high current battery. One false step and ----.Disclaimer: I do not pretend that this escapade is safe, or perfect. It is entirely unsuitable for anybody else to try.
My amplifier let the magic blue smoke out - Page 1
Forum section: electronics / projects

author: gnif
author_rank: Unknown
timestamp: February 13, 2014, 08:04:12 am
content: Hi all,A few weeks ago my sub woofer stopped working and I finally found time to pull it apart and have a look at it, seems the switching power supply has failed and let the smoke out. Thankfully the silkscreen has all the component values marked on it, so even the parts that are charred beyond recognition are identifiable.The bad side, one of the parts has damaged the silkscreen also when it failed, and as such I can not identify what it was with 100% certainty. It is clearly a resistor, but I do not understand enough of what is going on here to make an educated guess as to what the value would have been. The part in question is R18 in the attached image, from what is left of the silkscreen, it looks like it could have been a 300ohm resistor, but I do not want to just replace it and hope for the best.R18 is across the base & collector of one 13001, and the base of the other 13001, I think (with my limited understanding) that this is a biasing resistor.So far I have replaced:R22 (was burned to a crisp)R34 (ditto)DZ1 (open circuit) was a 15.2V zener, but silkscreen shows it should be a 13.6V, which I have used as a replacement.DZ2 (open circuit) was a 15.2V zener, and the silkscreen matches.D6 (open circuit)L1 (cracked in the middle)Q9 (dead short across all pins)Thanks in advance.

author: gnif
author_rank: Unknown
timestamp: February 13, 2014, 08:48:07 am
content: I replaced R18 with a 330ohm resistor and attempted powerup, DZ1 and R34 failed instantly with a loud pop, seems something else has failed also.Edit: Found the fault , seems the 13001 was also faulty, reads a dead short between two pins, which caused the massive current flow through DZ1 causing it to fail, and then R34 followed suit.Edit: :S, I feel like such an idiot... I put a 220ohm in there instead of a 220K resistor, I ordered some 220K resistors and did not check when they arrived, I was shipped the wrong values.
My battery charger board design, any comment? - Page 1
Forum section: electronics / projects

author: Porama6400
author_rank: Regular Contributor
timestamp: February 14, 2021, 11:06:48 am
content: Hi,I am currently trying to design my own battery charger/protector circuit.I am not an Electronic Engineer, and I am not quite sure what am I doing.so any comment on my abomination of a board would be appreciated,I would love to improve my board designing skillThank you

author: Peabody
author_rank: Super Contributor
timestamp: February 14, 2021, 03:52:35 pm
content: Will you be charging the battery and powering the load at the same time? If so, will the maximum load current be less than the charger's termination current so charging will terminate properly? Here's an app note with information on this problem - see Figure 5.http://ww1.microchip.com/downloads/en/AppNotes/01149c.pdf

author: Porama6400
author_rank: Regular Contributor
timestamp: February 16, 2021, 06:45:05 am
content: Quote from: Peabody on February 14, 2021, 03:52:35 pmThanks, I totally forgot about that.I didn't planned with charging while powering load in my mind, but I suppose that's something I should implement.

author: gnuarm
author_rank: Super Contributor
timestamp: February 16, 2021, 09:17:07 am
content: You asked for comments, so non-positive comments are included I suppose. Not trying to be mean, but I can't read your schematics. You leave 90% of each page empty, spreading a 1 page design over three pages. Rather than connect points with wires, you give each pin on every component a net name which the reader has to search for to find the connections.The primary difference between a net list and a schematic is that the schematic is supposed to be graphical showing connections with lines representing wires. Loose that and it becomes just a net list.I can't tell exactly what the design is doing. I would need to pull up the reference design on the data sheets to figure that out. Should I assume this is charging Li-ion batteries? How many cells/what voltage? What capacity?

author: Porama6400
author_rank: Regular Contributor
timestamp: February 16, 2021, 11:35:32 am
content: Quote from: gnuarm on February 16, 2021, 09:17:07 amThanks,non-positive comment is crucial for learning process I suppose, I really appreciated itWhich part of the schematic do I suppose to put those specs (voltage, cell, charge current) in?

author: gnuarm
author_rank: Super Contributor
timestamp: February 16, 2021, 12:13:43 pm
content: You could show the battery connection clearly and note it there. Admittedly I didn't spend a lot of time trying to dig into the design. My eyesight is poor so I have to blow up text to read it. With the design spread out so much I had to keep panning around to try to figure out the design.I looked at it a bit more and I guess I'd need to read the data sheets as some of this is not at all obvious to me. Are you sure the two FETs are connected correctly? They are usually source to source, not drain to drain.I did figure out where the battery is connected, VCELL_P AND VCELL_N connecting at J5. Can't say I understand what J4 is for.
My biggest fan is a right pain in the ear... High frequency noise from HVLS fan - Page 1
Forum section: electronics / projects

author: Jackster
author_rank: Frequent Contributor
timestamp: September 14, 2024, 10:33:18 pm
content: Just installed a HVLS fan in my workshop and while the performance of the fan is great, there is an annoying high pitch noise coming from either the motor or the controller.As you can see, around 14kHz there is a nice line. I have isolated it in audio software and it is the same pitch as the noise when walking around my factory.The noise comes and goes as you walk around and just tilting your head down can make it go away.You can only hear the noise when the fan is moving or starting. When idle, there is no noise.Here is the motor controller board.Any thoughts on what could be causing this and how to fix?

author: uer166
author_rank: Super Contributor
timestamp: September 14, 2024, 10:51:48 pm
content: 14 kHz sounds like the motor controller frequency: the noise is coming from the fan windings/laminations. Not much you can do other than get a different motor controller that works at a higher F.

author: Jackster
author_rank: Frequent Contributor
timestamp: September 14, 2024, 11:06:43 pm
content: Would some ferrite beads on the controller to Motor wires and a EMI filter on the AC input be of any use?Ideally I don't want to go messing with another controller. Did not work out well last time I tried to program one...

author: moffy
author_rank: Super Contributor
timestamp: September 15, 2024, 12:14:57 am
content: Well I guess the motor controller converts single phase into 3 phase out, but I can't see any power switches such as IGBTs etc. If 14kHz is the PWM frequency, sounds reasonable(no pun intended), then you could well get lamination noise. Ferrites won't be effective at such relatively low frequencies unless wound into largish inductors. The solution would be to filter the 3 phase output with a suitable LC filter to remove the PWM component.

author: Jackster
author_rank: Frequent Contributor
timestamp: September 15, 2024, 12:16:45 am
content: Quote from: moffy on September 15, 2024, 12:14:57 amThere is a large heatsink in the rear of this board. Would guess they are on the rear of the PCB.

author: amyk
author_rank: Super Contributor
timestamp: September 15, 2024, 03:05:08 am
content: Has the stator been dipped in varnish?
My CPU Design in an FPGA Via Collaboration with Dr. Kevin Walsh & Logisim - Page 1
Forum section: electronics / projects

author: mcsoftware
author_rank: Contributor
timestamp: February 18, 2020, 11:26:14 pm
content: I put this in the FPGA forum, but it appears that's the wrong forum.My new video shows my CPU design put into actual hardware (FPGA board) via a collaboration with Dr. Kevin Walsh. This CPU is based on the 16 instruction microprocessor I designed for a homework assignment many years ago, though it now has many more instructions.To view a playlist of my CPU design videos, go to:https://www.youtube.com/playlist?list=PLLQoKy-hD9LDG8PeMiZYN15O2eP1DfYTBor see my channel's video list:https://www.youtube.com/MrMcSoftware/videos
My Nothingburger - Page 1
Forum section: electronics / projects

author: sourcecharge
author_rank: Regular Contributor
timestamp: July 21, 2020, 10:24:26 am
content: At the Home of Nothingburger

author: duak
author_rank: Super Contributor
timestamp: July 22, 2020, 12:36:20 am
content: I'm intrigued by your design. Do you have a theory of operation, or could you summarize it? It's a bit difficult to offer a review if it takes a lot of effort to try to figure it out.

author: b_force
author_rank: Super Contributor
timestamp: July 22, 2020, 01:50:46 am
content: I am intrigued as well, but do you also know you can do the same with just some XOR ports as well?
My DIY ebay parts desktop light - Page 1
Forum section: electronics / projects

author: FireFlower
author_rank: Regular Contributor
timestamp: April 17, 2016, 02:44:33 am
content: Testing high intensity led work lightBought parts from ebay, can't find panel on ebay anymore but there are similar ones. Probably blows up like every other chinese panelControl panel is standard chinese dc-dc step-down converter board but this one has input and output voltage display. Shows 0.1 volts under but otherwise pretty much on spot. Rated for 3 amps (LM2596 chip) with extra cooling.Connected another 10k pot. resistor with two 2.2 kOhm resistors in paraller to set up my min voltage around 6 volts and highest voltage around 10-12 volts.50W led panel which has 10 super bright leds. Accepts input voltage of 7.5 to 37 volts. Less voltage draws less power, after power peak (50-60W) amperage starts dropping down until input voltage is too high and panel shuts down.Wanted to use it passively but with 'overdrive' it produces so much heat that you cannot anymore touch heatsink.Now have to make an enclosure for control board and mount the led panel and heat sink into a shade and a support.
My DIY joystick project for both old Commodores/Ataris, and USB - Page 1
Forum section: electronics / projects

author: Stephan
author_rank: Newbie
timestamp: July 05, 2020, 04:40:59 pm
content: Hi!Am new here in this forum, and was just helped very kindly in another thread, so thought I should give something back:Just wanted to show you my DIY project of a joystick for Commodores/Ataris, which also has a USB port:I tried to make it as beginner friendly as possible, with all plans providedUses Attiny microcontroller and V-USB to do the USB bitUses a NE555 based astable multivibrator for adjustable rapid fireHas a 2nd logical fire button, which is supported in quite a number of Amiga games, and even a few Commodore 64 ones, like Paradroid Redux.In its newest version it has a 4 digit 7 segment display to display the auto-fire frequency, and for port configuration (Amiga and C64 use different 2nd fire button signals), all by the same microcontrollerComes with stripboard layout and parts list, also has a PCB layout for the version without the displayAm also describing how to use USB-CComes with a comfortable shopping list for parts with a german electronics online shopHere's a Youtube video of the display in action:https://youtu.be/-EysjGoyjyYSo far only one joystick of the version with display exists (at least that I know of):Here one of the first ones I built, still without 2nd fire button, but uses USB-C:Good old self-made stripboard. Nice and optimized - I've used every horizontal line of it. Also in its newest version with display the pins of the microcontroller are now fully maxed out.Here's the project page:https://gitlab.com/edge-records/joyweilerMy plans for next winter or so are to make it all SMD and reduce components to use the Microcontroller for everything, for it to be the only IC needed.
My effort to suppress external interference in integrator - Page 1
Forum section: electronics / projects

author: passedpawn
author_rank: Contributor
timestamp: July 23, 2022, 10:41:35 pm
content: Previous designs showed some susceptibility to external interference. It's a very sensitive integrator. I've never used one of these shields before. Wish me luck.

author: David Hess
author_rank: Super Contributor
timestamp: July 24, 2022, 01:17:26 am
content: I had a problem with a pair of integrators operating as part of the oscillators for PWM controllers injection locking to each other. The first thing I tried, which happened to work, was to add LCR decoupling to both circuits to isolate them from power rail noise and each other.
My Electronic DC Load Project - LCD DEMO - Page 1
Forum section: electronics / projects

author: Prithul0218
author_rank: Contributor
timestamp: January 22, 2019, 06:15:48 pm
content: Hello.TL;DR: Showing you the LCD Demo UI I made for a DC load. Looking for suggestions and feedback.I'm making a digital electronic DC load. I am using Arduino UNO as the main processor for now, but will later change it to a nano.This is my progress with the code. I have made a simple LCD user interface with a 20x4 HD44780 LCD. I have a keypad, a rotary encoder and a load on off button for interaction. Here's a video of me showing you the user interface. Please forgive me for the poor setup. I'm recording on my phone camera.https://youtu.be/bIl2wxz3hIsThere are a few things I want to point out:Button A is for choosing mode. D is for removing a digit. * Is for placing decimal point and # is being used as enter key.The load on off button is simply connected to a digital pin which tells the microcontroller to set the DAC output to 0. It's not a hardware on off button. The light around the on off button turns on when the device is active.I have not implemented any speed detection for the rotary encoder in the code yet.I am still working on the mode selection menu. It doesn't look very pretty.I am not sure if I want to keep the constant voltage mode as it will need some additional circuitry. I don't think I can do it from the software. Can I?I have not designed the schematic yet, it's all in my head.I am using Scullcom Hobby Electronics' DC load as an inspiration, but not copy pasting the codes in any way. I am making it completely from scratch. I want to thank Louis Scully for his awesome DC load build.I am not sharing the code right now as I think it looks very messy. Will upload it here later once it's finished.And finally, I would highly appreciate any suggestions/ideas.Thank you.
My experimental 16 MEMS USB Microphone Array - Page 1
Forum section: electronics / projects

author: Georgy.Moshkin
author_rank: Frequent Contributor
timestamp: September 25, 2025, 03:30:00 pm
content: I've been putting a lot of effort into a project I'd like to share here - a USB microphone array with 16 analog MEMS microphones.The main idea:1) Work as a plug-and-play USB microphone with default firmware2) Serve as a playground for experiments with custom firmware — beamforming, audio effects, etc.Current hardware:- 16 MEMS microphone cells (LMA3722T421-OA5 with OPA376 preamp), arranged in a 2D grid- STM32H7B0VBT6 (Cortex-M7 @ 280 MHz) handling real-time audio processing- ES8388 stereo codec with headphone amplifier- microSD slot for standalone recording- 3.5 mm audio output for monitoring headphones- 3.5 mm audio input (future firmware features)- RX-8025T RTC with DTCXO for precise long-term sampling rate- LSM6DSRTR IMU for orientation/impact sensing- Dual USB-C ports: one for normal operation, one for recovery/first firmware flash- Live/Mute status LEDs (firmware-dependent)I’m planning a mixed model: some snippets of code will be free on GitHub (mainly for experimenting with JavaScript-based algorithms on the signals), while the optimized real-time firmware will remain closed-source.

author: RJSV
author_rank: Super Contributor
timestamp: September 25, 2025, 07:15:07 pm
content: Nice!I'm not sure, reading, if that's a single preamp, or one preamp per microphone ?I'm doing an audio project, BTW, and so my antennas went up. Post more when you can, please, as it's new stuff for myself to absorb (and smile). -Rick

author: TimFox
author_rank: Super Contributor
timestamp: September 25, 2025, 09:04:28 pm
content: So you plan to use phased-array techniques for beamforming? Sounds interesting.

author: Georgy.Moshkin
author_rank: Frequent Contributor
timestamp: September 26, 2025, 03:12:10 am
content: Quote from: RJSV on September 25, 2025, 07:15:07 pmYou are correct, this was a typo. There are 16 mics with separate opamp per each microphone. First, I've tested 3 different MEMS microphones (the green board), simple inverting opamp configuration was more than satisfactory, so I just multiplied it on a newer board. Btw, I feel like antenna stuff will be significantly delayed by this microphone project.Quote from: TimFox on September 25, 2025, 09:04:28 pmYes, and I've got some tricks from radar signal processing on the same chip - 8 channels but with much higher sampling rates. I expect FFT-based methods challenging, mainly because of "watery" artifacts and not performance. I plan to record some multi-channel audio synced to webcamera video, and then experiment with the recording using html+javascript playground. If there is something good - implement it in STM32 firmware.
My finished COILGUN - Page 1
Forum section: electronics / projects

author: Miroslavus
author_rank: Newbie
timestamp: February 17, 2018, 03:22:31 pm
content: Hi, I have been working on my coilgun for few months and wanted to share it with you. It has six coils driven directly from Li-po batteries instead of charging caps. Definitely not the most powerful one but I wanted efficiency instead of raw power. That just turned out to be pain in the butt to program since I don't even have an oscilloscope. Anyways I have almost made 3D printed enclosure and all of the files available on thingiverse and instructable if anyone is interested in building one:https://www.instructables.com/id/Coilgun-1/https://www.thingiverse.com/thing:2787867I'd also like to thank @fourtytwo42 who helped with some of my troubleshooting. I'm just hobbyist so the gun is far from perfect. Especially the sketchy electronics. I've made whole video about it going into details and just by building it I realized few things I could have done better but I'd like to hear you guys think.https://youtu.be/2pzM9yLSBMo

author: joeqsmith
author_rank: Super Contributor
timestamp: February 17, 2018, 04:17:44 pm
content: I was skipping around the video to try and find where you were firing the gun but no luck. Could you post a few time links? Thanks.

author: Miroslavus
author_rank: Newbie
timestamp: February 17, 2018, 04:53:13 pm
content: it's in the first minute

author: Wimberleytech
author_rank: Super Contributor
timestamp: February 17, 2018, 05:14:52 pm
content: Impressive!
My first 4 layer PCB - Page 1
Forum section: electronics / projects

author: Spark-Doctor
author_rank: Contributor
timestamp: October 28, 2018, 08:28:30 pm
content: Hi allI am laying out my DC Load project and it has become apparent that it will be a lot easier if i go to a 4 layer board.The board is 235x170mm. I don't need it this big but is was always going to be bigger than 100x100 and the board flipper did not penalise me for jumping to this size and i have designed it to fit the bottom of the case i am putting it in.After a lot of research, i propose my layer stack as,Arduino Nano and control circuitsGroundLoadOther power CircuitsQuestions1) I have several negative voltage rails, which layer should they go on?2) On the "load" layer, is it better to just flood the entire layer even though i don't need that much area or can i split it in 2 and with anappropriate gap, have 2 different voltage planes on the same layer?3) I have a mixture of SMD and through hole so rater than lots of via's, i was going to flood the top layer with a ground as well. Good or Bad?This will probably be the first of many questionsThanks in advanceIan

author: DaJMasta
author_rank: Super Contributor
timestamp: October 28, 2018, 11:54:10 pm
content: I wouldn't put load traces on the inside. Typical stackup is signal, ground, power, signal as a general guideline, but typically inner copper layers are thinner (half ounce, usually), and since they're on the interior, any heating takes much longer to dissipate, so it's not ideal for high current stuff. If you run a primary power rail on the interior, have a ground that is essentially uninterrupted, then maybe keep analog on one and digital on the other, you should be able to do most of what you're looking for. If you need multiple rails, you can divide up the power plane (or route traces to specific places), but it may be simpler and better for the stability of that rail to just use a wide trace on the top or the bottom if those other rails are only going to a couple places.By the size of the board, you probably don't have so many traces that you'll have to sacrifice much in terms of organization to get everything routed (maybe a double sided with a few jumper links would even do the job), so I'd make an effort to leave the power and ground planes uninterrupted (and single rail on the power plane), and then if it seems like the routing is nasty somehow, consider breaking the power plane for other rails then.

author: jbb
author_rank: Super Contributor
timestamp: October 29, 2018, 01:59:02 am
content: I totally recommend using a whole layer for a big group plane, and trying hard not to cut it up. The second inner layer should probably be power distribution.I recommend keeping your inner layers as simple as possible, because they’re nearly impossible to wire mod.I usually pour ground over all layers and stitch them together with vias (maybe 15mm spacing? Or 5mm if you’re sticking BT / WiFi on it).
d - Page 1
Forum section: electronics / projects

author: Unknown
author_rank: Unknown
timestamp: September 28, 2015, 11:32:16 pm
content: d

author: alexanderbrevig
author_rank: Frequent Contributor
timestamp: September 28, 2015, 11:40:06 pm
content: Welcome!After a rough glance it seems to me you'llneeda bettery actually connected (and regulator enabled in order for you to use the barometric sensor. Is this intended?Also, I would not cut out decoupling capactiros for the AVCC and VCC lines. Be sure to place capacitors close to the pins for best performance

author: jwm_
author_rank: Frequent Contributor
timestamp: September 29, 2015, 02:46:36 am
content: Have you checked the quiesent current of your buck-boost regulator/minimum load? Some can be quite voracious. I recently ran into one with a 20ma standby current independent of load. And to think I originally added it in to improve battery life, trading losing half a ma via a linear regulator for 20ma continuous draw. doh.

author: ralphd
author_rank: Frequent Contributor
timestamp: September 29, 2015, 03:17:20 am
content: I'd go with a 662k ldo to reduce board space and save cost. If the barometic sensor can take 4.2V then drop the regulator. Or run directly from a LiFePO4 battery.Try driving the piezo directly; you may get enough volume and then can drop the transistor.If your code size is not large you could save a bit by using an ATmega8a.Is the 10-pin header ICSP? The 6-pin version would save some more board space.Lastly, if the barometric sensor needs less than 5mA, you could run everything off a CR2032.

author: microbug
author_rank: Frequent Contributor
timestamp: September 29, 2015, 07:04:19 am
content: Step 0: use KiCad (oranything else but Eagle).

author: obiwanjacobi
author_rank: Super Contributor
timestamp: September 29, 2015, 02:22:14 pm
content: Quick scan:Only one terminal of SL1 is connected? Also the pad right next to it is unconnected.There are a number of holes that seem to serve no purpose?
my first ctcss generator - Page 1
Forum section: electronics / projects

author: christopher iles
author_rank: Regular Contributor
timestamp: August 22, 2014, 10:43:18 am
content: Built a ctcss generator to put in my old Icom IC-215 rig. Was quite pleased that my budget multimeter read the output. If anyone wants a picture of the pcb I made I can post it. The circuit is not mine however, I found it on the internet and just had to add an extra resistor to make it work.
My first ever simple breadboard PSU - Page 1
Forum section: electronics / projects

author: antolanca
author_rank: Contributor
timestamp: June 21, 2016, 08:52:49 am
content: Hello EEVBlog.Gonna build my first ever dual voltage PSU but would like your opinions on it.On paper and simulated in Yenka it works. But in your more experienced view will it work?Thanks in advance for any help.

author: Ian.M
author_rank: Super Contributor
timestamp: June 21, 2016, 09:05:27 am
content: Totally useless. The '5V' setting will output around 3.5V and the '3.3V' setting will output around 2.5V, sagging approximately 1V for every 3mA of load current!If you are starting from a 5V USB charger, then all you need for the 5V setting is a 200mA polyfuse to provide over-current protection. The 3.3V output needs a LDO regulator with decoupling caps as specified in its data sheet. Use a SPDT center off switch at the OUTPUT to select the voltage 5V from before or 3.3V after the LDO regulator.Also indicator LEDs go across the supply, with a current limiting resistor in series with the LED, *NOT* in series with the output!

author: ZeTeX
author_rank: Frequent Contributor
timestamp: June 21, 2016, 03:41:58 pm
content: Get an adjustable low dropout linear regulator and be done with it - cheap, easy, and reliable and also adjustable voltage.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: June 22, 2016, 01:09:46 am
content: http://www.ebay.com/itm/Continuously-Adjustable-Regulated-DC-Power-Supply-DIY-Kit-LM317-1-25-12V-US-V7M2-/131743251138?hash=item1eac827ac2:g:4nEAAOSwwpdW2QAb

author: dannyf
author_rank: Super Contributor
timestamp: June 22, 2016, 01:14:36 am
content: QuoteIf you are to use it to power very low load (a few ua for the lower one and a few ma for the upper one), it can be of some use.Try to get a 3-terminal regulator and you can pretty much wire it up on the breadboard itself. Much simpler and far more useful than what you have here.
My first LED driver - minimum PWM with 555? - Page 1
Forum section: electronics / projects

author: alcs2000au
author_rank: Contributor
timestamp: May 17, 2020, 01:29:05 pm
content: Hi guysI am currently designing my first LED driver around theTPS61165for theBridgelux Gen 7 V10LEDs. I would appreciate a quick check on the circuit and some guidance on how to calculate RT1, RT2 in the third image below, to get the minimum 25% duty cycle (so I get minimum 100ma supplied to the LED). I wanted to use a 555 for the PWM signal because that way the PWM generating part could also be replaced by a microcontroller if needed.Thanks

author: madires
author_rank: Super Contributor
timestamp: May 17, 2020, 03:21:58 pm
content: Let's start with the LED driver. It won't work that way.COMP should go to C4, FB to R1 and SW to L1. The PWM duty cycle is determined by the trimmer, i.e. the resistance ratio between charge and discharge. If you want a minimum duty cycle you would have to add an additional resistor to the charge path. For a minimum duty cycle of 25% that resistor should be 25% of the trimmer.

author: alcs2000au
author_rank: Contributor
timestamp: May 17, 2020, 07:20:12 pm
content: Thanks :-) I must have played around with the other use cases too much. How about like this?Cheers

author: madires
author_rank: Super Contributor
timestamp: May 18, 2020, 09:27:18 am
content: The next step is to test your circuit.
My First PWM Motor Controller - Page 1
Forum section: electronics / projects

author: nikodean1
author_rank: Newbie
timestamp: July 20, 2016, 02:45:06 pm
content: Hi everyone.I recently made my first motor controller. It is a PWM fan speed controller for DC fans up to 80 watts: You can see a demonstration of it here:I used a Launchpad RM57L development kit to run the C code, which adjusts the PWM signal's duty cycle based on the analog to digital converter's reading. The fan speed will vary from 20% of the maximum to 100%, depending on the temperature.

author: moffy
author_rank: Super Contributor
timestamp: July 21, 2016, 12:00:35 am
content: Nice. I must say that TI have done a great job supporting ther Launchpad series. I used the TM4C123g and everything worked as advertised right out of the box.

author: Circlotron
author_rank: Super Contributor
timestamp: July 21, 2016, 02:05:50 am
content: Your board doesn't look like it is in a static safe environment.Don't be surprised of it fails soon.

author: nikodean1
author_rank: Newbie
timestamp: December 13, 2016, 03:10:36 pm
content: Quote from: Circlotron on July 21, 2016, 02:05:50 amOk, is there a container you would recommend?
My first time looking for DAT0, CMD, and CLK on eMMC. Does this look right? - Page 1
Forum section: electronics / projects

author: marcosscriven
author_rank: Contributor
timestamp: May 23, 2023, 07:10:39 pm
content: Looking at this image from my scope, would you agree that from top to bottom it's DAT0 (yellow), CLK (purple), CMD (cyan)?I'm guessing this on the basis CMD is just briefly at the begging/end, the CLK is constant while data is transferring, and DAT0 is on but much less consistent.Incidentally, at the about the 3/4 mark on the first screenshot, no idea why all three signals suddenly look 'fuzzy'?