hybridfree/eevblog-posts huggingface dataset:
MSOP10 SMD IC identification - Page 1
Forum section: electronics / beginners

author: costi_b
author_rank: Newbie
timestamp: October 24, 2017, 10:12:02 am
content: Please help me with the identification of an integrated SMD circuit.It is marked 0L J or OL J. The last letter differs from one copy to another.It is manufactured by Analog Devices

author: amyk
author_rank: Super Contributor
timestamp: October 24, 2017, 10:46:44 am
content: That's clearly an MSOP10.

author: tszaboo
author_rank: Super Contributor
timestamp: October 24, 2017, 10:54:18 am
content: AD doesnt have a disclosed reference for the package marking. I would write them an email.It is probably a MSOP-10 package though.

author: costi_b
author_rank: Newbie
timestamp: October 24, 2017, 11:29:23 am
content: Yes, it is MSOP10. I changed the title.Thank you for the answers.
MSP430FR5969 launcher problem - Page 1
Forum section: electronics / beginners

author: Karamel
author_rank: Regular Contributor
timestamp: March 09, 2017, 07:53:41 pm
content: Hi,I have a problem with msp launcher kit. I downloaded CCS studio v7 and I connceted launcher to my pc and my pc recognized it MSP application uart1 and(com3) and MSP debug interface(com4)I, briefly, clicked new project, new ccs project, selected my target device corrcetly and clicked asm project. Empty asm file opened. When I clicked debug icon, I get this error which is shown below.So, what is the problem?

author: Karamel
author_rank: Regular Contributor
timestamp: March 09, 2017, 08:38:10 pm
content: I uninstalled my ccs studio v7 program and now, I can't download ccs studio software on ti web site.

author: suicidaleggroll
author_rank: Super Contributor
timestamp: March 09, 2017, 08:42:34 pm
content: You're trying to debug an empty file, what did you expect it to do if not throw an error?

author: Karamel
author_rank: Regular Contributor
timestamp: March 09, 2017, 08:48:23 pm
content: No,ccs studio defines all things when you start new asm project. all registers etc defined my empty project. I think this is not about empty or not, This is another issue.Now, I cant reach setup files of ccs on ti web site.

author: stefanh
author_rank: Contributor
timestamp: March 09, 2017, 11:10:34 pm
content: Have you tried downloading the setup files from the following link?http://processors.wiki.ti.com/index.php/Download_CCS

author: Karamel
author_rank: Regular Contributor
timestamp: March 10, 2017, 01:11:20 pm
content: Last night, this link couldn't open. Two hours before, I downloaded ccs v7 and now, It works. I guess, I didn't set it up correctly first time.
MSP55LV100S Read / Program - Page 1
Forum section: electronics / beginners

author: GadgetUK
author_rank: Contributor
timestamp: November 04, 2013, 11:33:19 pm
content: Hi,Sorry if this is in the wrong section... I am after a bit of advice on how to reprogram a MSP55LV100S chip. I believe these are NVPROMs, which I think I should be able to reprogram with the correct hardware. I cannot find a data sheet for this device so I am a bit clueless where to begin.I have one of these on a PCB, and I am sure its corrupted - generating noisy sound on Neo Geo MVS. I can remove the chip but not sure how to go about reprogramming it. Does anyone know of a cost effective way / programmer to do this?I've got a couple of EPROM programmers but they are for 40 pin or less chips, and I am guessing this particular chip could have some serial interface or something for programming? I've also got a USB 3 in 1 JTAG programmer but not sure if that could be used or not without understanding how this chip works, or more specifically the pin out etc.

author: amyk
author_rank: Super Contributor
timestamp: November 05, 2013, 08:36:54 am
content: Game system? Most likely mask ROM, followed by PROM. Neither are reprogrammable.

author: GadgetUK
author_rank: Contributor
timestamp: November 05, 2013, 10:34:14 am
content: Sorry but your assumption is incorrect. These chips have been reprogrammed already - I can tell they've been reclaimed from other systems. Just need to work out how I can reprogram them.
MSW inverter question  - Page 1
Forum section: electronics / beginners

author: LawfulMeteor710
author_rank: Newbie
timestamp: December 20, 2022, 06:39:44 pm
content: Can an electric vehicle be charged using a modified sine wave inverter or does it need to be a Pure Sine Wave inverter?My son-in-law want to use a battery and inverter to charge his Mini in a emergency.

author: Zero999
author_rank: Super Contributor
timestamp: December 21, 2022, 01:04:41 am
content: Quote from: LawfulMeteor710 on December 20, 2022, 06:39:44 pmPossibly. Ask the manufacturer.

author: SmallCog
author_rank: Frequent Contributor
timestamp: December 21, 2022, 01:44:26 am
content: What sort of battery is he intending to use? It would need to be something sizeable to be of any use

author: LawfulMeteor710
author_rank: Newbie
timestamp: December 21, 2022, 07:58:03 am
content: Regular lead acid car battery. He just wants to use it to get a few miles to get to nearest charger.
MT223 soldering iron for $10 (Bogus? or can it really regulate temp?) - Page 1
Forum section: electronics / beginners

author: Cliff Matthews
author_rank: Unknown
timestamp: May 15, 2017, 01:05:34 am
content: Can one really expect regulation at 10 bucks? Youtuber Andreas Spiess briefly has this cheapie open at around 20:05 (https://youtu.be/DEEaLMv6dog?t=1205). I ordered one of these for my son, but does anyone think this could be a good candidate for either an external or internal mod?

author: KL27x
author_rank: Super Contributor
timestamp: May 16, 2017, 11:13:53 am
content: I skimmed the vid. So what I gather is it has variable power. And the sticker says 60W. So no, this isn't temp controlled.As long as the power range is wide and smooth enough, and the power rating is close, this thing should be capable of most anything. Weller makes variable power irons, still.The main practical problems with variable power vs temp control boils down to 1. the nature of the tip running hottest when it's on the stand doing nothing. The problem is greater as the tip gets smaller in thermal mass compared to the joints that need to be made. Then you need to run even hotter on standy. And 2: the recovery between joints will also take longer, because instead of using the full 60W to recover, it is only using the amount of power that is dialed in.There's probably a triac in there for the power control. I can imagine some mods, but I don't know how you'd fit it in there and have mains safety. Say a switch that will ground the gate*, so that you get full power, instantly. You could set the dial down lower, to a standby level, and hold the button down for a second while moving it to make a joint. Then the iron wouldn't crust over and burn out the plating while idling in the stand. Or maybe a reed switch that will reduce the power output by pulling up the gate*, activated when you put the iron on a stand with a magnet in it.*I could very well have this reversed. My working memory is tiny. And my hard disk takes awhile to access. In either case, it should be one leg of the potentiometer or the other that is what I mean. The wiper is going to go to the gate of the SCR, and you would bias the gate from one of the outer legs to move the power level in one directon of the other.
MT3608 booster in CC mode. - Page 1
Forum section: electronics / beginners

author: Fabiosapplou
author_rank: Newbie
timestamp: January 09, 2021, 09:19:12 pm
content: Hi guys, I would like to know if any of you have any idea on how do I make a MT3608 in to a constant current mode, I’ve tried using a LM358 as differential amp on a 0.33R on the output feeding a 0.6v Vref on to the feedback pin of the MT3608 ic, but I don’t seem to be able to get it working. I have not seen anyone doing it but i think it should be possible though, probably my design it’s no good. Any help? Thank you.

author: tanveerriaz
author_rank: Contributor
timestamp: January 11, 2021, 11:46:58 am
content: cc for led driverhttp://www.eddy.com.ua/archives/887https://ahkur.ru/?p=322
MT9700FFFUBG Help - Page 1
Forum section: electronics / beginners

author: Evilmitaka
author_rank: Newbie
timestamp: August 24, 2025, 11:29:51 pm
content: I need the datasheet or some help for this chip is from a digital drawing monitor, what needs to go to that pin? originally it came from the usb input selector.

author: amyk
author_rank: Super Contributor
timestamp: August 25, 2025, 01:50:00 am
content: https://datasheet4u.com/pdf-down/M/T/9/MT9700FCLE-MediaTek.pdfis the "FCLE" variant but it's in the same package? That pin is a NC there.

author: Evilmitaka
author_rank: Newbie
timestamp: August 27, 2025, 02:56:46 am
content: Thanks for the info.
MTD2114G datasheet - Page 1
Forum section: electronics / beginners

author: Maurizio1957
author_rank: Contributor
timestamp: September 14, 2020, 02:57:49 pm
content: Hello all, why I can find hundreds of sellers for MTD2114G stepper motor driver, but no datasheet available??73, Maurizio IU5BEC

author: Maurizio1957
author_rank: Contributor
timestamp: September 15, 2020, 01:47:45 pm
content: ... and the same for TB6577AFG BLDC motor driver....Maurizio
MTPA Reference block Settings in Simulink (MATLAB 2020a) - Page 1
Forum section: electronics / beginners

author: cadena
author_rank: Contributor
timestamp: April 15, 2020, 11:20:33 am
content: Hi everyone,I am failrly recent to MATLAB and SIMULINK. I am trying to use to Motor Control blockset in Simulink to implement an FOC algorithm. I am using the MTPA Reference block for Simulink to calculate the Id and Iq currents for me but there are parameters in the block I don't understand. What is the difference between max current and base current ? How do you calculate stator d-axis inductance ? Is this given in the motor datasheet or do we have to calculate it ? And if so, how do I do it ? What is the per-unit (PU) in I/P singal units ? Why would you choose this rather than SI units ? Also is the permanent magnet flux linkage meant to be in the motor datasheet ? I am modelling the iPower Gimbal motor GBM2804H-100T. Please your help would be really appreciated.MTPA Reference Documentation link:https://www.mathworks.com/help/mcb/ref/mtpacontrolreference.html

author: Vovk_Z
author_rank: Super Contributor
timestamp: April 15, 2020, 08:03:27 pm
content: Base current here is only for per unit conversion.Max current - hm, it can be rated current of motor (I'm not sure).
MTS310 Sensor Board Schematics - Page 1
Forum section: electronics / beginners

author: nsh1233
author_rank: Contributor
timestamp: July 08, 2014, 03:23:45 am
content: I'm doing a school project and i am suppose to draw the schematics of this MTS310 sensor board on Altium Designer. But i'm not sure what 2conpads and 4conpads mean? (Refer to picture) Please help.

author: nsh1233
author_rank: Contributor
timestamp: July 08, 2014, 03:41:00 am
content: sorry posted on the wrong category
Multi channel design in altium - Page 1
Forum section: electronics / beginners

author: caltroniks
author_rank: Newbie
timestamp: July 14, 2021, 05:32:00 pm
content: Hellorecently ,a Schematic and PCB that has come to me for modification has the schematic using Multi channel and Multi schematic approach ,if i get the the terms correctly here.Could you/anyone in the fourm kindly look at the attached image share your thoughts.I am lost about it and not sure what s the problem hence not able to reolsve itLooking forward to hearing from youBest RegardsAlun
Multi-channel variable constant current source - how to implement ? - Page 1
Forum section: electronics / beginners

author: michaeliv
author_rank: Frequent Contributor
timestamp: May 25, 2015, 10:34:20 am
content: Hi,I'm looking to create a circuit that will have 10+ constant current outputs. The current on each output needs to be the same ( and adjustable ).I could just create 10 different current sources with their own individual potentiometer and adjust each of them, but what I'm looking for is that all outputs should be controlled from a single input .The only thing I've been able to think of so far is to create 10 different constant current sources using an LM317/LM334/Transistors and vary them through 10 different optocuplers which are controlled by an input potentiometer ( picture attached ). I'm not 100% sure if this would work and I get the feeling that there should be a much better solution.Input voltage is 9v and output current ( on each output ) : variable 0.1mA - 10mA. Each output has independently varying impedance.Any suggestions ?Thx!

author: macboy
author_rank: Super Contributor
timestamp: May 25, 2015, 12:39:00 pm
content: Lookhere.repeat the op-amp and output transistors for each output; use a single voltage reference and control pot to generate the single control voltage for all of them.

author: michaeliv
author_rank: Frequent Contributor
timestamp: May 25, 2015, 07:38:59 pm
content: From the link you gave me + searching around for similar implementations ('voltage controlled current source') I found exactly what I was looking for, Thanks.

author: Jebnor
author_rank: Regular Contributor
timestamp: May 25, 2015, 09:44:26 pm
content: Quote from: michaeliv on May 25, 2015, 07:38:59 pmSee also "Current mirror". For 100uA to 10mA you might be able to use a simple current mirror.
Multi-channel Voltage & Current Measurement test setup advice? - Page 1
Forum section: electronics / beginners

author: danielbriggs
author_rank: Regular Contributor
timestamp: August 11, 2019, 05:26:52 pm
content: Hi there EEVBlog Hive-Mind,I'm after a bit of advice on the most sensible way to do the following and would appreciate anyone's input / advice.In short:I would like to measure the voltage and current, accurately, of at least 3, potentially up to 5 laser diodes simultaneously.In long:I have a proper way of controlling and measuring one diode during initial testing + design, using one of these:https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=4053But would like a way of getting the current and voltage of a bunch of laser diodes while they are hooked up to a suitable driver as a kind of "servicing / production tool". [They are already connected up to a suitable current source, but the drivers have no kind of current read back facility].The current range through the laser diodes would be in the range of either: 0-0.5A or 0-2.0A (depending on diode type) and forward voltage would be between 2.5-7.5V for all types.Would like to measure with at least 1mA resolution across entire range, and 10mV for any forward voltage.I've found the burden voltage of my U1251B or Keithley 2010 is too high to put inline with the diodes for accurate current measurements, so would appreciate some advice on how to best measure this accurately. Hall effect sensor? Are they accurate for <1A at 1mA resolution + accuracy though?I've read some bits about external current shunts, but have no idea how best to select one over another, let alone their suitability for "multi-channel measurements".To scale this up to simultaneously measuring 3-5 diodes for both voltage and current, do I use a whole bunch of DMM's with a lower burden voltage? [Dave's 121GW's looked a good choice at 0.03V/A]Or do I use some kind of multi-channel DAQ that measures voltage only, and use 3-5 µCurrent's to sense the current and convert to a voltage output?If I go down the "multi-voltage" measurement route, I looked at adding the option of a 2000-SCAN scanner card to the 2010 7.5 digit meter, if that's a cheap and sensible way to do this?If anyone has any pointers on both:A. the simple case of accurately measuring current reliably when a laser diode is connected.andB. how to scale this voltage+current measurement up for multiple channels (3-5 of each voltage and current) in a kind of basic "servicing / test setup" without spending a million pounds.Thanks in advance.All the best,Dan
Multi-color/ bi-color LED ( 2 cathodes and 1 anode) - Page 1
Forum section: electronics / beginners

author: Dr_Taco_Cat
author_rank: Contributor
timestamp: August 26, 2014, 12:20:37 am
content: Hello, I was wondering if there are any multi-color/ bi-color leds that have 2 cathodes and 1 anode. I am working on a project and I want to use 1 multi-color led, but the IC's pins go to ground. I am using 2 pins on the IC ( UCS1001-2-BP-TR ) that show attach detection and/or an error. All of the leds available seem to only have 1 cathode and 2 or more anodes. Is it possible to make a single LED with 2 or more cathodes and 1 anode? (if it is possible, im trying to get through hole parts not SMD, but any info will help )This is the kind of led i'm looking at, but this one only has a single cathode/common.http://optoelectronics.liteon.com/upload/download/DS20-2001-645/S_110_LTL1BEKVJNN.pdf

author: David_AVD
author_rank: Super Contributor
timestamp: August 26, 2014, 12:41:21 am
content: All of the 3-pin bi-colour LEDs I've used were common cathode. The Digikey parametric search doesn't have a CA / CC selection which is ominous.You can definitely get RGB LEDs in CA or CC though. Maybe that's near enough for your needs?

author: ludzinc
author_rank: Unknown
timestamp: August 26, 2014, 12:44:09 am
content: http://lmgtfy.com/?q=common+anode+led+ebay+bi+color

author: Corporate666
author_rank: Unknown
timestamp: August 26, 2014, 01:01:17 am
content: In addition to the above suggestions (which are good ones), what about using a dual transistor in a small SOT23 (or smaller) package to switch your CC LED with a pair of grounds from your chip? Do you have enough board space for another SOT package?

author: n6plm
author_rank: Newbie
timestamp: November 02, 2019, 03:12:19 am
content: I found this Lumex part: SML-LX15IGC-TR, red/green, common anode

author: mariush
author_rank: Super Contributor
timestamp: November 02, 2019, 03:15:40 am
content: Quote from: n6plm on November 02, 2019, 03:12:19 amAnd do you think the guy is still waiting for an answer? He asked in2014
multi function tester oddity - Page 1
Forum section: electronics / beginners

author: p.larner
author_rank: Frequent Contributor
timestamp: December 20, 2023, 09:18:44 pm
content: I have a cheap chineese t7 tester,it has been working ok but now shows as 2 diodes,1 diode between pins 1+2 with a vf of 1.25v and a diode on pins 1+3 with a vf of 1.25v also,this is with nothing connected to it,is it kapput?.

author: Jwillis
author_rank: Super Contributor
timestamp: December 21, 2023, 10:32:29 am
content: I would say so. I have one of those as well. Apparently everything is a diode.

author: u666sa
author_rank: Frequent Contributor
timestamp: December 21, 2023, 07:00:46 pm
content: I also have T7. Waiting for real ATmega, orderedhere.You need tomodify it.Thing is, when the chip is fake, you get crap results.Nowadays, all testers come with fake chips.

author: u666sa
author_rank: Frequent Contributor
timestamp: December 21, 2023, 07:02:36 pm
content: No it's not ubito, just fake chip giving you fake results.Start with photo of the board here. Then I can guide you to proper mod guide. Boards are different.

author: Jwillis
author_rank: Super Contributor
timestamp: December 21, 2023, 11:27:03 pm
content: Quote from: u666sa on December 21, 2023, 07:00:46 pmKilled mine testing a zener diode of all things. Go figure.Mine has the APT32F172K8T6. Is that the same as the LGT8F328 ? What about firmware?Was reading these for ideas.https://www.eevblog.com/forum/testgear/tc1-lcr-meter-transistor-tester-fix/msg4940884/#msg4940884andhttps://www.eevblog.com/forum/microcontrollers/apt32f172k8t6-chinese-32-bit-mcu-recently-seen-in-transistor-testers/msg4614097/#msg4614097

author: p.larner
author_rank: Frequent Contributor
timestamp: December 22, 2023, 01:07:34 am
content: i will tear mine apart tomorow and take a pic,its 1am here so can wait until the morning,is this a known fault then?,if so is it a hardware fault or firmware,if i remember the last thing i checked was a 5.1v zenner.

author: Jwillis
author_rank: Super Contributor
timestamp: December 22, 2023, 05:58:34 am
content: I've since bought ones of theseBSIDE ESR02proSo far it hasn't had a stroke measuring zener diodes.

author: p.larner
author_rank: Frequent Contributor
timestamp: December 25, 2023, 03:50:02 am
content: was going to tear mine apart and take pics but life got in the way,tbh i have more important things to be doing than messing with this piece of chink shit.

author: Jwillis
author_rank: Super Contributor
timestamp: December 25, 2023, 06:41:46 am
content: Quote from: p.larner on December 25, 2023, 03:50:02 amOh be nice. It took those guys a lot of effort to copy those chips.
Multi layer ceramic or poly caps? - Page 1
Forum section: electronics / beginners

author: Chris Wilson
author_rank: Super Contributor
timestamp: January 05, 2014, 09:09:58 pm
content: I have a box of polypropylene caps but am never sure where it might be appropriate to use them. For example, I have built this circuit attached. For C1 a 0.001uF cap is required. How would I decide if a disc ceramic or poly cap was appropriate? Thanks.

author: mariush
author_rank: Super Contributor
timestamp: January 05, 2014, 09:24:30 pm
content: I woudn't use ceramic capacitors for more than 20-30v - with ceramic capacitors, the capacitance drops as the voltage on them goes up so for 20v on them, i would use at least 50v, preferably 100v rated ceramic capacitors.There are probably more experienced people who will give other tips so I'll stop here. Must admit I'm not experienced with polypropylene capacitors - i actually assumed you meant polymer capacitors.

author: SeanB
author_rank: Super Contributor
timestamp: January 05, 2014, 09:36:24 pm
content: Ceramic where you do not care as to the actual capacitance, or that it varies with voltage. Polypropylene where you want a stable value. Basically anything involving coupling audio, or for timing. For the reference you show disc ceramic 100V or better is fine, but you can use the polyprop there as well with no problems. If it is a bias for an audio amp use the polyprop caps as then it will be more stable with varying current.

author: Chris Wilson
author_rank: Super Contributor
timestamp: January 05, 2014, 09:43:16 pm
content: Thanks mariush and SeanB It's a cathode bias for an RF linear amp, adjustable, no less. I was going to use a string of diodes but thought "What the heck, let's be fancy"What about at RF, for decoupling, are poly caps still OK? I appreciate COG or similar caps are needed in tuned circuits to guard against drift. Cheers.

author: c4757p
author_rank: Super Contributor
timestamp: January 05, 2014, 09:53:12 pm
content: Fordecoupling you usually would use ceramic, as poly is overkill. And many of them have poor performance at RF. If you need stable capacitance at RF, use mica or C0G.
3v3 to 5v level converter alternative to TXS0108EPW - Page 1
Forum section: electronics / beginners

author: castingflame
author_rank: Regular Contributor
timestamp: June 22, 2020, 03:24:31 pm
content: I have a requirement for 5v to 3v3 bidirectional level conversion in my project for various buses and lines.I have 7 lines in total at the moment, which include 6 lines from a 5v MCU that consist of i2c: SDA SCL, Serial: TXD RXD, Software Serial: TXD RXD and an I/O line.I initially started using the standard MOSFET approach which works fine but as soon as I got to 4 lines I knew it was time to replace them with an IC due to part count, complexity, build time, error reduction etc etc.I am currently using a DIL breakout board with a TXS0108EPW which provided 8 lines of level conversion.DATASHEEThttps://www.ti.com/lit/ds/symlink/txs0108e.pdf?ts=1592838304954&ref_url=https%253A%252F%252Fwww.google.com%252FIt works perfectly for what I want but there is only one issue; The package size which is a 20-Pin TSSOP.While this will be going on a new design I am a little concerned to go that small / close pins. It will be soldered using a solder stencil and oven but it is a concern that I may start introducing an unneeded failure point with bridged joints. Every other IC in my design is the larger SOIC type footprint and I can handle them fine with a solder mask and my oven. I am relatively new to doing proper SMD designs and using solder stencils an soldering in my oven so I have kept at SOIC and 0805 type sizes and I dont want the handling and repairing to be a major headache either.So, I wondered if there was a similar IC to the TXS0108EPW that comes in a 20 pin SOIC package. At worse case if I will have to use the TXS0108EPW, I will, but if possible I would rather reduced the risk and find a part that is not so high density.I have only ever soldered one TSSOP package which was a 32 pin square device and I had to put the solder paste on by hand so maybe I am being over cautious and it would be fine with a proper solder stencil.Your experience and advice is welcomeThanks.
Multi meter and clamp meter accuracy ±(% of reading + number of LSD)  - Page 1
Forum section: electronics / beginners

author: dylanmitchell
author_rank: Contributor
timestamp: December 10, 2020, 12:20:51 am
content: Looking at multi meter and clamp meter specs I see ±(% of reading + number of LSD). I understand +/- percent but don't understand LSD or least significant digit. Please explain how this works. For example:Fluke 117 AC volt±([% of reading] + ): 0.5% + 2vsFluke 87 AC volt±(0.7% + 2) True RMSAmprobe 320 vs Fluke 325AMP320 AC amps±1.8% + 5LSD (50 to 60 Hz)vsFluke325 AC amps1.5% ± 5 digits±(% of reading + number of LSD)Where:Reading = the true value of the signal that the DMM measuresLSD = least significant digitWhere:Reading = the true value of the signal that the DMM measuresLSD = least significant digit

author: bdunham7
author_rank: Super Contributor
timestamp: December 10, 2020, 03:29:27 am
content: Suppose your meter is reading 10.00 volts (or amps) and has a specified uncertainty of 1% + 5 counts (or LSD--same thing as counts). This means that for the 10.00 indication, the real value might be as low as 9.85 or as much as 10.15. That's 0.1 volts for the percentage and 0.05 for the counts. What you don't often see is the confidence interval that goes with that specified uncertainty. 95% is common, so for a 95% confidence interval in this case, that means that there is a 95% probability that the real value is between 9.85 and 10.15.B/t/w, don't make the mistake of comparing meters from different manufacturers solely on the their specified uncertainties, especially when the numbers are close. These numbers come from the manufacturer, not any independent testing service.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: December 10, 2020, 03:36:13 am
content: If you've got enough LSD, all those numbers don't mean a thing anymore.But they move a bit and have nice colors.

author: bdunham7
author_rank: Super Contributor
timestamp: December 10, 2020, 03:39:41 am
content: Quote from: Doctorandus_P on December 10, 2020, 03:36:13 amOr their meanings become extraordinarily clear.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: December 10, 2020, 04:05:32 am
content: That is probably an illusion.
Multi meter Low impedance input, input protection - Page 1
Forum section: electronics / beginners

author: facosta
author_rank: Newbie
timestamp: November 05, 2016, 07:23:19 am
content: I would like to measure mains power stray voltage between neutral and earth for an isolation transformer project. I do not own a multi meter with low impedance range but can overcome the problem by jumping the multi meter's input jacks with a 10kohm resistor. If I probe between neutral and earth in the primary side or between earth any of the terminals on the secondary side everything is sweet. If a make a mistake and probe between active and earth primary terminals or in between both secondary terminals, the resistor allows quite a bit of magic smoke to escape. How can I protect the resistor without using a beefy one? Would a PTC resistor achieve this goal? What protection multi meter manufactures use for this issue?

author: Simon
author_rank: Unknown
timestamp: November 05, 2016, 07:32:38 am
content: in your case Id get a 7W resistor and do make sure your keeping stuff insulated.

author: facosta
author_rank: Newbie
timestamp: November 05, 2016, 09:39:52 am
content: Thanks Simon for your answer. Your solution is cheap and simple enough. Still trying to found another way to skin this cat I came across the Fluke 12B service manual @http://assets.fluke.com/manuals/12b187xxsmeng0000.pdfIn page 4.10 we can see what they use for their Low Z input protection one 1.1Kohm PTC resistor in series with a bunch of 470 ohms, 3W resistors. So it looks like this Low Z input is somewhere around 2k5ish ohms. It looks to me this configuration will dissipate a hell of power if something goes wrong with the PTC resistor. Is this thing even fused according to the schematics? Cheerio

author: jeroen79
author_rank: Frequent Contributor
timestamp: November 05, 2016, 10:33:51 am
content: You will have to decide on a combination of measures:-dissipate the power up to a point-then increase the impedance (ptc)-finally open the circuit if that still is not enough ((poly)fuse)And set a clear maximum voltage rating that the user should respect.

author: Kalvin
author_rank: Super Contributor
timestamp: November 05, 2016, 11:26:53 am
content: Alternative approach: You can also measure the current through the resistor, and use Ohm's law to calculate the voltage. Place a fuse in series with the resistor which will protect the resistor and your multimeter.

author: jeroen79
author_rank: Frequent Contributor
timestamp: November 05, 2016, 03:04:54 pm
content: How about using something like a low power mains rated lamp?It can dissipate the power and if it burns out the circuit will open.

author: facosta
author_rank: Newbie
timestamp: November 05, 2016, 08:21:26 pm
content: Thanks all for your answers. All your ideas will solve the problem. I was thinking more on a short of fixture small enough to sit nicely directly on the multi meter jacks when needed, so it cannot be too bulky. By the end of the day and analogue meter, been inherently a much low input impedance device, will do the trick but it will be trash in the toolbox in no time at all.
multi-minute sample runs on I2C bus? - Page 1
Forum section: electronics / beginners

author: skypuppy
author_rank: Newbie
timestamp: October 21, 2016, 06:16:04 am
content: I need to watch the I2C bus for several minutes, at least 5 and maybe up to 15 minutes. I bought a Bus Pirate V3, not knowing it has an itsy, butsy, teeny weenie, yellow polka-dot buffer size on it. So I looked at the Bitscope line and not finding buffer sizes, I emailed them. They suggested using PulseView to bypass their (small) buffer and just write directly to the host PC. As a test, I installed PulseView on the Debian Linux box (27 inch screen,) connected the Bus Pirate but can find no method in PulseView to make long term samples. Is this possible? If not, how do I do what I need to do, please? Oh, I very much need the protocol analyzer to work.Further, is it possible to only store sample timestamps along with it's data, to save disk space and bandwidth? 15 minutes of 100khz I2C data would be an enormous file size.Thanks,Newbie
Multi Object Tracking Sensor ? - Page 1
Forum section: electronics / beginners

author: pyroesp
author_rank: Regular Contributor
timestamp: July 17, 2017, 03:01:49 pm
content: I have an idea for a project which will need an MOT sensor, something like what the Wiimote uses.The IR camera inside the Wiimote can track up to 4 points, I think. It has SPI communication and only sends the coordinate of the 4 points to the MCU.The camera is a PAC7010 from PixArt Imaging Inc. They have a newer model it seems that can track up to 16 objects.I would like to buy some of those IR cameras, but can't find them anywhere and I tried to contact PixArt but I have yet to receive a reply.Any idea where I can find this sensor or do you know of a similar sensor ?I would like not to have to buy a Wiimote just for the sensor alone.

author: raulgotor
author_rank: Newbie
timestamp: November 23, 2017, 08:30:52 pm
content: Hi,Any news or ideas on this? I'm also interestedRegards

author: EverydayMuffin
author_rank: Regular Contributor
timestamp: July 24, 2020, 11:27:08 am
content: Jumping on this old thread in case anyone else is looking for this information in the future.Pixart now have a distributor covering all of Europe:https://www.epsglobal.com/manufacturers/pixart
Multi-Tapped inductor question - Page 1
Forum section: electronics / beginners

author: parabuzzle
author_rank: Contributor
timestamp: November 19, 2013, 03:52:43 pm
content: I'm working on a HAM radio antenna tuner for myself and I don't have the money to buy a nice rotary inductor at the moment. So I am using the multi-tapped inductor design with a selector switch.This is essentially what I am making:So I am using a 12 position selector switch to control which tap the tuner should use. The switch I have really only has 11 positions because one of the positions is the feed point that is permanently shorted to the center ring so I that point is what I would call "off" because when I put it in that position its not connected to any other pin. I don't want to have an option of opening the circuit like that and I would like to utilize that point as well. So I was thinking that I would connect that point to the output side of the full inductor length and then use the switch to shorten the inductor to different lengths. My question is, will this cause the RF to become reverse-biased in the section of coil that I am bypassing given that I now have 2 paths for it? Is it a problem or is this even feasible? Or should I just be happy with the 11 positions/tapsThis is a simplified design of what I am talking about.. nevermind the components used.. I just used representation parts I found in eagle:-Mike

author: Rory
author_rank: Frequent Contributor
timestamp: November 19, 2013, 06:41:30 pm
content: Shorting out turns in switched inductors is the norm. Look at diagrams of antenna matching networks in the ARRL Handbook for examples.

author: JackOfVA
author_rank: Unknown
timestamp: November 19, 2013, 08:05:27 pm
content: Take a read ofhttp://vk1od.net/tx/concept/TappedCoil/-- good analysis of the difference between open circuit and short circuit of unused turns.

author: parabuzzle
author_rank: Contributor
timestamp: November 19, 2013, 10:43:23 pm
content: Quote from: JackOfVA on November 19, 2013, 08:05:27 pmThis is exactly what I didn't know I needed to read-Mike
Multi-voltage power supply design - Page 1
Forum section: electronics / beginners

author: Silverspur
author_rank: Newbie
timestamp: December 12, 2023, 04:41:34 pm
content: I need help/reviewing with the design a PCB power supply.I'm designing a board (or a set of boards) to automate the management of a pool.I have the following 'blocks' :An ESP32 SoC -3.3VA pH & ORP probe "reader" board -low drift 5VRelays to control 230V pumps -independent 5V(connection to ESP32 outputs is made through optocouplers)A DS18B20 temperature probe -5VThe 5V for the pH/ORP probes reading is done using one of two outputs of a LT6658 (low drift, high accuracy power supply). The other output will bes used to power the temperature probe.Board(s) general power supply is AC power (220-230V).I imagine the following combination:220V - HLK-PM09 - 9V - LT6658 - 5V - pH/ORP probes (output 1) & DS18B20 probe (output 2)220V - HLK-PM01 - 5V - relays? - 3.3V - ESP32The HLK-PMxxparts will be equiped with fuses and varistors for safety.What do you think of this setting? Regarding the ESP32 power supply, is it best to use a 3.3V regulator (such as AMS1117) connected on the 9V supply, or else to use an additional dedicated HLK-PM03?Thanks a lot for you help!

author: PSR B1257
author_rank: Frequent Contributor
timestamp: December 12, 2023, 06:15:55 pm
content: QuoteRather complicated.Why do the pH and temperature-probes need independent power supplies?QuoteNeat modules. I would only use one of them and derive every voltage from that.Maybe a second one only for the relays, but than rather 12V/24V since that is a more common "industry-voltage" for relays and contactors. Speaking of relays, make sure, they are rated for motor-loads. A "10A relay" is only good for switching a 10A resistive load.

author: Silverspur
author_rank: Newbie
timestamp: December 14, 2023, 01:15:06 pm
content: Thanks for your answer!QuoteFrom what I undestand, the voltage supply needs to be very stable for the probes readings to be accurate (more stable than what a standard regulator can provide).QuotePerfect, this makes sense. I was planning to use 5V since I already have a 5V relay, but it is not clear that it is rated for motor-loads so I might have to check and adjust

author: Kleinstein
author_rank: Super Contributor
timestamp: December 14, 2023, 04:37:24 pm
content: PH probes are not that sensitive. There accuracy is anyway limited by temperaure effects. So one does not need a super stable reference. A normal 78L05 or 1117 type LDO should be good enough.The PH probe itself is a high impedance voltage source and modern OP-amps for the amplification have a rather good PSRR. Battery operated meters may even use a 9 V block directly with no regulation. The tricky part with the PH probe may be getting good isolation and to avoid leakage in a high humidity environment.Pool control also does not need lab grade accuracy.
Multichannel OVP module/circuit for I/O - Page 1
Forum section: electronics / beginners

author: GU49A
author_rank: Newbie
timestamp: November 16, 2018, 08:14:37 am
content: Hi!Is there any sort of multichannel over-voltage protection module or IC for digital I/O?Let's say I have my DIY controller PCB with 32 pushbuttons and 32 relays. The buttons and relays are wired up 'outside' and exposed to all sorts of 'intruder' attacks like applying AC mains to inputs/outputs (up to 240VAC I guess), or high-voltage shocker strikes, shorting wires etc.. I need my pcb to survive the attack (even if pushbuttons/relays are destroyed).Initially I thought of putting a separate PTC+TVS+pcb-spark-gaps (or GDT?) protection on every channel, but soldering dozens of those are kinda unfavourable.Is there a better solution? How to reduce the number of components and pcb space required?P.S. There are ULN2004-like ICs for inputs and 'smart-protected' switches for outputs, but I suppose they won't survive on its own?
MULTICOMP electrolytics? - Page 1
Forum section: electronics / beginners

author: flolic
author_rank: Frequent Contributor
timestamp: February 20, 2012, 09:30:18 am
content: Farnell has them, and they are generally cheaper than the brand names. Are they any good, for stuff like SMPS?Low ESR, GLR series.Thanks!

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 20, 2012, 10:06:58 am
content: Multicomp is not a real brand, just Farnell's badge for stuff from obscure suppliers, and the actual source may change over time.As for suitability for a particular application, read the datasheet.

author: flolic
author_rank: Frequent Contributor
timestamp: February 20, 2012, 11:28:15 am
content: Yes, I know about datasheets, but want to hear about real life experience with them

author: Simon
author_rank: Unknown
timestamp: February 20, 2012, 12:38:15 pm
content: as stated above real sources change all the time so any recommendation is pointless, by the sounds of it they are no good for low esr stuff like smps

author: flolic
author_rank: Frequent Contributor
timestamp: February 20, 2012, 01:52:54 pm
content: Yes, that make sense.I will choose something with name

author: Simon
author_rank: Unknown
timestamp: February 20, 2012, 01:59:39 pm
content: just make sure it has a specified esr, that is a starting point in determining that it is reasonably low. Often no mention of the esr means that it is to high for hi frequency work like smps

author: amyk
author_rank: Super Contributor
timestamp: February 22, 2012, 12:05:23 pm
content: Quote from: Dave.S on February 21, 2012, 07:16:22 pmDon't forget Rubycon, Nichicon, and Nippon Chemicon, they're also known for good caps.
Multicomp waveform generator - Page 1
Forum section: electronics / beginners

author: ricard2k
author_rank: Unknown
timestamp: March 17, 2021, 08:30:46 am
content: I´m looking for a programmable waveform generator, and I found this distribuited by farnell:https://ie.farnell.com/multicomp-pro/mp750511/waveform-generator-2ch-60mhz/dp/347922460 Mhz sine wave for 500 eur plus taxesDo have somebody experience with this brand?

author: Zero999
author_rank: Super Contributor
timestamp: March 17, 2021, 08:43:04 am
content: Multicomp is Farnell's own brand, which means it could be just about anything rebadged. It should be fairly decent quality and you have all the aftermarket support and confidence provided by Farnell, but you can probably get exactly the same thing much cheaper elsewhere.

author: Berni
author_rank: Super Contributor
timestamp: March 17, 2021, 09:14:25 am
content: Yep Multicomp and Tenma are just Farnells store brands, much like the store brand noodles you might find in your local supermarket.So anything with Multicomp or Tenma is actually some cheep chinese brand rebadged and sold under that name. So the benifit for buying from farnell is mostly that its easier to warenty it, no need to ship it around the world, and easier to return it if its faulty.Sometimes they are too lazy to even blank the logo. Look at the attached screenshots of one such PSU. This is the same PSU that ElectroBoom always uses on his youtube videos but there it is branded as "CirucitSpecialists", we have one of these horrible PSUs here and its a "Blanko" brand.

author: giacomo
author_rank: Regular Contributor
timestamp: March 18, 2021, 12:45:21 am
content: From the look it resembles the owon XDG2060For what would you use it ?

author: tautech
author_rank: Super Contributor
timestamp: March 18, 2021, 07:14:32 pm
content: Quote from: giacomo on March 18, 2021, 12:45:21 amFor sure it is:https://www.owon.com.hk/list_waveform_generatorsFarnell, RS and most of them rebrand products and generally you can source them cheaper from the OEM agents, resellers and distributors.

author: rstofer
author_rank: Super Contributor
timestamp: March 18, 2021, 07:45:16 pm
content: As with most AWGs, the high frequency (60 MHz in this case) only applies to the sine wave. The square wave is limited to 30 MHz and the ramp to 3 MHz.Pages 1-2 here:http://www.farnell.com/datasheets/3047900.pdf
Multicore HMP Solder - Page 1
Forum section: electronics / beginners

author: azureflash
author_rank: Newbie
timestamp: September 06, 2014, 04:55:49 am
content: Hello everyone, I didn't double-check the solder I was getting and accidentally bought a roll of Multicore HMP Ersin 366 solder wire, which is apparently a high melting point solder formulation (93.5% lead 5% tin 1.5% silver) with "extra activated" 1% Halide flux core, for ultra fast line assembly hand solder, difficult solder surfaces, increased creep resistance, operating temps -200C to +250C, blablabla...That's all neat, but it's pretty wildly different from the standard 60/40 or 63/37 rosin activated stuff I was thinking of getting. As a beginner who has never soldered before, can I use this stuff with relatively little extra trouble or would it be worth it to try and exchange with Digi-key for something more standard? My iron can handle it (brand new Hakko FX-888D), but I'm worried I'll make messes on boards with that extra activated 1% Halide flux, or that I'll be restricted in the kind of components I can solder due to that high melting point...Side question, I'm a bit of a perfectionist and I'd like to clean the flux residues and produce really nice-looking boards, so what can I actually use to clean either that 1% halide extra active flux or the normal rosin flux? Is 99% alcohol and kimwipes okay, or do I need a special solvent? If for example I need a special solvent for HMP solder but not the standard stuff, then that would be one more reason to try and make an exchange or buy another roll sooner...

author: tautech
author_rank: Super Contributor
timestamp: September 06, 2014, 08:41:06 am
content: Quote from: azureflash on September 06, 2014, 04:55:49 amWelcome to the forum.Get yourself a small amount (or 2) of low or medium temp solder and keep some of the HMP for any mains or high temp work.Many of us have several different types for various uses. Mixing with lead-free for easier re-work, more active flux for dirty/old work, hard types for higher stress and our favorites of course.
Multicore Solder - Page 1
Forum section: electronics / beginners

author: gridds
author_rank: Newbie
timestamp: May 11, 2018, 06:08:14 pm
content: Just a general solder question. I found a seller for Multicore solder - 63/37 (tin/lead) 0.38mm 370 Flux 5 Core.However I can't seem to find any information on the web for 370 63/37 0.38mm, I found 60/40 0.38mm. Would this be a safe buy? Packaging looks legit.Unsure about posting the AD, it is listed on eBay, seller has received it from HGR Industrial Surplus.

author: Audioguru
author_rank: Super Contributor
timestamp: May 11, 2018, 06:38:11 pm
content: 63/37 solder hardens suddenly when cooling and always makes a good solder joint but 60/40 solder goes though a "plastic phase" which causes a poor solder joint if the wires move while the solder is cooling.Why buy a cheap maybe Chinese unknown solder from ebay? Instead buy a Name-Brand solder from a REAL local electronics distributor.

author: Gregg
author_rank: Super Contributor
timestamp: May 11, 2018, 07:36:11 pm
content: Google genuine Multicore solder and look at the pictures, then compare to the picture on FleaBay. If they can't even copy the label well, how much effort do you suppose they put into the solder?
Multimeter Diode Test on Transistors?? - Page 1
Forum section: electronics / beginners

author: Robbie010
author_rank: Contributor
timestamp: February 06, 2019, 06:44:01 pm
content: Evening all,I got myself a cheap Multimeter today that has a Diode test setting. I read online that this can be used for checking transistors but when I test one it just gives me a number without telling me what it is i.e V, mV etc etc, so what exactly is this test telling me?When testing an MPS L01 (BJT NPN) Transistor I get the following readings:Leg 2-3 = 518Leg 2-1 = 521Is it forward voltage?Thanks

author: mikerj
author_rank: Super Contributor
timestamp: February 06, 2019, 06:53:58 pm
content: That will be the forward voltage in millivolts.

author: Robbie010
author_rank: Contributor
timestamp: February 06, 2019, 07:01:42 pm
content: Thank you very much.And is this number variable dependent upon the voltage in or would it remain constant (to a certain point)?

author: David Hess
author_rank: Super Contributor
timestamp: February 06, 2019, 08:15:24 pm
content: Those numbers are the forward voltage drop of the two junctions. If your measurements are good enough, which includes not holding the transistor in your fingers while making the measurements because the forward voltage drops change by about -2mV/C, then I believe the emitter junction will have a slightly higher voltage drop than the collector junction. But the diode test is mostly useful for verifying that neither junction is open or shorted rather than revealing anything about performance.

author: Aubrey999
author_rank: Newbie
timestamp: February 07, 2019, 09:01:52 am
content: Yes, from my experience, I find that the resistance of the Emitter is usually the higher one, regardless if it is NPN or PNP.So that is a way to work out the polarity of the transistor, and the lead-outs.