hybridfree/eevblog-posts huggingface dataset:
Tektronix DM 44 - Page 1
Forum section: electronics / projects

author: uberblitz
author_rank: Newbie
timestamp: January 10, 2013, 08:16:39 pm
content: I recently acquired a Tektronix 475A with DM-44 multimeter option. I haven't had the time to crack it open yet, but the DM-44 always reads out ".3.3.3.3" on the display regardless of what the settings are. Does anyone know what this error code means? I am unable to find a service manual for it thus far

author: PA0PBZ
author_rank: Super Contributor
timestamp: January 10, 2013, 08:49:53 pm
content: Service manual:http://elektrotanya.com/tektronix_dm44_for_465_475_szkop_dmm_puttony_1976_sm.pdf/download.htmlIt even gives an explanation for the 3.3.3.3 in the troubleshooting flowchart. (pg. 9-26)

author: uberblitz
author_rank: Newbie
timestamp: January 10, 2013, 09:03:32 pm
content: Thanks for the link! I was having a difficult time locating that.Looks like it wants me to check U3340 to make sure it is still working. I will crack this thing open this weekend.

author: PA0PBZ
author_rank: Super Contributor
timestamp: January 10, 2013, 09:16:19 pm
content: Good luck with that, and if it doesn't work out let us know.
Tektronix Oscilloscope THS720A handheld, halve full of ants, wierd and nasty - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: May 01, 2025, 07:21:30 am
content: I still cant understand how they get in,why they choose to move in, and and live inside a handheld scope,i am no expert of how ants work, but this is a bit wierd and nasty,funny how they made one corner their restroom, and another corner their living room,all details herehttps://youtu.be/gjyoiBXohNk
tektronix plasma switches - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: January 18, 2025, 05:30:24 am
content: I was reading about plasmatrons on wikipedia and I ran into thisALC was originally developed by Thomas Buzak, who worked at Tektronix in the U.S. Through the late 1980s and early 1990s he developed and patented a number of concepts that used plasma to provide a switching element for a variety of usesI looked at his patents and almost everything was specific to the display technology.Does anyone know what the more general patent relating to 'variety of uses' might be?

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: January 21, 2025, 01:50:28 pm
content: Buzak’s work was associated with Tektronix.You can search patents assigned to Tektronix in the 1980s and 1990s with "plasma" and "switching".
Tektronix PS503A +5vdc mod - Page 1
Forum section: electronics / projects

author: CaptDon
author_rank: Super Contributor
timestamp: September 14, 2022, 05:06:34 pm
content: The original circuit was simply a 7805 +5vdc regulator chassis mounted for heat sinking and self limiting at 1 amp. Tektronix published a mod that made the +5vdc variable and they sold a kit to do the mod. The mod can be done simply with parts from the junkbox. First off the Vin runs around 11.5vdc so that is good. Remove the chassis mounted 7805 regulator and mount an LM317 'sideways' in place of the 7805. The LM317 MUST be insulated from the chassis with a sil pad or mica insulator as well as an insulating shoulder washer for the mounting screw. The original screw and nut can be used. Run the 11.5vdc (located at pin 1 of the original 7805) to Vin of the LM317 and connect the Vout of the LM317 to Vout (located at pin 3 of the original 7805). The adjustment circuit I used was a 3.9 volt zener (anode end to GND located at pin 2 of the original 7805) and the cathode end connected to the low side of a 100 ohm front panel mounted trimpot. The wiper of the trimpot goes to ADJ pin on the LM317. The high side of the trimpot goes to a 150 ohm 1/2 watt resistor and the opposite end of the resistor goes to Vout. You may want to place a small .1uf to perhaps 1uf from the high side of the trimpot to the wiper. I also added a 1000uf @ 10vdc capacitor across the red and white output jacks. There is room to mount a trimpot to the left of the white 5vdc return jack above the release pull tab. My Bourns trimpot needed a 1/4 inch hole. My adjustment range seems to be from 4.6vdc to 5.5vdc and the LM317 can also source 1.5 amps which is a nice improvement over the original 1 amp.
Tektronix TDS6XX/7XX power ups, running time - Page 1
Forum section: electronics / projects

author: wtcoon
author_rank: Newbie
timestamp: January 31, 2016, 05:02:41 pm
content: I come across a lot of Tektronix TDS6XX/7XX scopes and I am looking for a way to query the number of power cycles and total runtime experienced by the unit via GPIB. Couldn't find anything in the service manual or programmers guide. Thanks for your time.
TekVISA on Linux - Page 1
Forum section: electronics / projects

author: blueskull
author_rank: Unknown
timestamp: June 06, 2017, 08:37:10 pm
content: Is there a way to install a set of libraries that allows me to talk to a Tek DSO2024B scope with a Linux computer?I know this can be done on Windows with TekVISA and OpenChoice, but I would like to know how to do the same on Linux.I know it may also be done (not sure) wuth LAN port and web interface, but I don't have a LAN/VGA module at this moment.The goal is to create an automated power semiconductor characterizing tool, and so far we have the high power things done, but we need waveform grabbing capability, and it seems using an existing scope and its probes is the cheapest and fastest way.Any suggestions are appreciated.

author: cdev
author_rank: Super Contributor
timestamp: June 07, 2017, 12:26:12 am
content: Is any of this helpful?You should also see if the software you want to run runs under Wine and if it does, if it is stable enough for you."wine is not an emulator" its an execution environment which is quite stable with some programs, Some programs, especially older programs often run just as well under wine as they do under windows. Sometimes even better.These were found looking for stuff using very generic search terms..I use Debian Linux and have been able to use around 90% of the windows apps I need to use, in Wine, with a little effort. My Windows requirements are pretty modest but it is worth a try.Butit may be unnecessary because as time goes on, the chances are better and better that you can find some other way to get the data you want out using Linux.Check web sites for SBCs like RaspberryPi.org too. They are very popular in lab settings.https://askubuntu.com/questions/257636/how-to-connect-tektronix-tds10001b-to-ubuntuhttp://www.febo.com/geekworks/data-capture/tds-2012.htmlhttps://stackoverflow.com/questions/13921618/collect-more-than-10-000-data-points-from-a-tektronix-oscilloscopehttp://www.tek.com/support/faqs/how-can-i-communicate-tektronix-instrument-unix-or-linux---https://github.com/pyvisa/pyvisahttp://www.ni.com/visa/https://www.mathworks.com/matlabcentral/fileexchange/20640-using-tektronix-open-choice-with-matlabhttps://github.com/NaoPross/TekVisaOscilloscope

author: Marco
author_rank: Super Contributor
timestamp: June 07, 2017, 03:08:02 pm
content: Can't you just use USBTMC (I think there's a driver in mainline Linux) with the commands fromthe programmer's manual?

author: voltsandjolts
author_rank: Unknown
timestamp: June 10, 2017, 12:07:05 pm
content: Python USBTMC intro
TekVisa vs NI Visa issues - need suggestions - Page 1
Forum section: electronics / projects

author: rfdes
author_rank: Regular Contributor
timestamp: December 27, 2022, 01:44:31 pm
content: Hopefully someone can give advice as to a solution to my problem.I use a Win 10 laptop as an interface to control my tektronix logic analyzer using Ethernet for connectivity. The tektronix analyzer uses ver 5.8.151 of their application software and works fine. I also want to use python, along with pyVisa in order to control some additional instrumentation using a NI USB GPIB controller.My issue is that the Tek analyzer software uses their implementation of VISA (TekVisa). However, pyVisa doesn't work properly with TekVisa (at the least the version that is used with the analyzer application). If I install NI Visa, pyVisa works just fine but the Tek analyzer application is not happy.If it is possible to install both VISA implementations simultaneously I cannot find how to to do it. The only other thing I haven't tried and really don't want to is to run one or the other on a virtual machine. I guess the VISA architecture confuses me as I thought that the standard would allow compatibility but that isn't true in my situation.Any suggestions would be appreciated.Thank you.

author: joeqsmith
author_rank: Super Contributor
timestamp: December 27, 2022, 02:44:55 pm
content: Doubt I can be of much help. I used a TekVISA to control one of their Arbs using Ethernet. It was actually slower than using the instrument's GPIB interface. I never used it with Windows 10 but did have NIVISA installed with it. I've not used pyVisa but if you have an example that can be used to replicate what you are seeing, I can maybe try it out. Stay with common hardware. Maybe use the pyVisa to talk with a serial port.

author: walter.aranda
author_rank: Contributor
timestamp: July 12, 2024, 03:03:34 pm
content: Hello, I am experiencing the same problem. I saw here that it might be a compatibility issue since you might be running Python in its 64-bit version, which can be verified with:python -c "import struct; print(struct.calcsize('P') *"And that you might be running VISA in 32-bit.
Telecom 'rectifiers' - Page 1
Forum section: electronics / projects

author: najrao
author_rank: Regular Contributor
timestamp: February 08, 2018, 06:09:05 am
content: Time was when I picked up anything with PWM from the surplus market here, and so I have loads of boards, assemblies and modules, from milliwatts to several kW and 3.3V to 60 and over. From servers, mainframes, and -- telecom stations.These last are 27V (older), or 54 the most. From 1 to 4kW each. The latest ones are very efficient (95+%)and compact (80×80×400 puts out 4kW), 90 to 300V 50/60Hz input, good for 65C air temperature, and made for over 100 000h MTBF. Meant for battery charging, control of a group of rectifiers is by dedicated master controllers, not usually available to ordinary mortals. They are hot pluggable to backplanes (again not available) through custom sockets and plugs. Needless to say, they have very good PFC, so need a minimum of a.c. input current.I *have* converted just one 2kW unit into a very good CV/CC bench supply. 0 to 58V, and 0 to 60A (power limited), with no hiccups and a dead on crossover from CV to CC. Needed extreme surgery to locate control nodes among the myriad surface mount ic's, not an exercise to be repeated on others.A major problem is the non availability of mating connectors for the PWRblade sockets. Making soldered wire-outs for up to 80A involves too much heat.The 'control' pins, from just 8 up to 24, are another pain in the you-know-where. Similar to server PSU's, you need to identify PSON, PSKILL, SENSE, VMARGIN, I SHARE, and the ubiquitous Tx and Rx. Little or no data is forthcoming.With only a few scrapped, I have restored more than a dozen of these. I want to put them to use, and request suggestions on what to. I have 3-phase 415V to feed up to 20A, and the usual 230V separately, at home here, so power is not a limitation. I was considering making a 200+A dc welding PS, from 3×3kW units. Is any help forthcoming? Much appreciated.

author: najrao
author_rank: Regular Contributor
timestamp: February 10, 2018, 12:34:11 pm
content: Come on, surely my question deserves *some* response? So many wizards out there, say your piece! Thank you sir/s.OP

author: fourtytwo42
author_rank: Super Contributor
timestamp: February 12, 2018, 09:00:17 pm
content: No pictures or links, hardly suprising, actually what was the question

author: najrao
author_rank: Regular Contributor
timestamp: February 13, 2018, 09:21:52 am
content: I considered that pictures would not add value, but attach a few now, these are just examples. There are many more models and ratings, several of each in cases.I did ask for suggestions: 1. Can I make a dc welding source from 3×3kW units? Need hand-holding to do this. 2. How to make high current connections to (the) PWRblade output sockets. 3.How to identify control pin-outs. Perhaps I should have been more explicit.To let know that I may have the competence to take up such project, I did say that I have already converted a 2kW unit to a CV/CC variable PS.One and all, please help!
Telecom question: USSD 2G 3G - Page 1
Forum section: electronics / projects

author: Spikee
author_rank: Frequent Contributor
timestamp: August 10, 2016, 03:43:22 am
content: Hello All,I have a question regarding USSD and disappearing GSM networks.So USSD works over the voice channel which would be GSM.The problem is that several countries are phasing out of GSM and 2G (and thus the voice channels?).So here are the questions:- The USSD provider told me that if there is no 2G network the voice channel still exists, is that correct?- If GSM/2G is phased out there are no voice channels left right ? thus USSD won't work anymore.I'm not closely involved in the project. These are just some questions others have and I thought someone on this forumprobably has expertise in this. Getting confusing / contradicting answers from others.Thanks
Telefunken Concertino 7 Radio - Repair and restoration - Page 1
Forum section: electronics / projects

author: jcrubin
author_rank: Frequent Contributor
timestamp: November 06, 2017, 01:33:10 pm
content: I had cosmetically repaired this radio years ago but never got around to doing the electronics work until now. With this I have created a series to document this effort.Part 1 of 5

author: jcrubin
author_rank: Frequent Contributor
timestamp: November 13, 2017, 12:59:38 pm
content: Part 2 of 5

author: jcrubin
author_rank: Frequent Contributor
timestamp: November 20, 2017, 02:47:28 pm
content: Part 3 of 5

author: jcrubin
author_rank: Frequent Contributor
timestamp: November 27, 2017, 01:06:16 pm
content: Part 4 of 5

author: jcrubin
author_rank: Frequent Contributor
timestamp: December 04, 2017, 12:48:57 pm
content: Part 5 of 5
Tell me what you see in this waveform? - Page 1
Forum section: electronics / projects

author: BillW50
author_rank: Contributor
timestamp: July 30, 2015, 06:20:02 pm
content: Using analog scopes for decades and being new to digital scopes. I believe I have it figured out, but I want to know what you see in this waveform. I want to know what you see; like voltages, frequencies, peak to peak, averages, etc. If you are curious, this is from a GW Instek GDS-1062A scope using GW Instek Freewave software. I'll probably tell you later where I got this waveform from at a later date. As many of you are probably wondering where the hell did I get this waveform at?http://youtu.be/rCOSrg08FYA
temp lithium ion charging - Page 1
Forum section: electronics / projects

author: p.larner
author_rank: Frequent Contributor
timestamp: October 25, 2023, 08:50:37 am
content: my 13s 54.6v ebike charger died,i wave a 10s unit at 42 volt for lithium ion,so i am 12 short,can i put a cat battery in series with the 12v car battery to charge my pack?.

author: Siwastaja
author_rank: Super Contributor
timestamp: October 25, 2023, 08:53:28 am
content: No.
Temp sensor inside IC? - Page 1
Forum section: electronics / projects

author: MT
author_rank: Super Contributor
timestamp: January 28, 2018, 12:44:29 am
content: What kind of sensor config design could this be? The process is 0.8um bipolar from the mid eighties.

author: CopperCone
author_rank: Super Contributor
timestamp: January 28, 2018, 12:55:58 am
content: isent this commonly done with bandgap references?https://en.wikipedia.org/wiki/Bandgap_voltage_reference

author: David Hess
author_rank: Super Contributor
timestamp: January 28, 2018, 07:01:55 am
content: 3300ppm/C is 0.33%/C and the change in Vbe for a forward biased diode at about room temperature. What you are looking at there is a diode connected transistor or just a diode.

author: MT
author_rank: Super Contributor
timestamp: January 28, 2018, 03:27:04 pm
content: Ops! I forgot to tell that sensor is to cancel the temp drift of a exponentiation/logging circuit, so a more complex bandgap or another equal logger (but that have issues) for temp sensing or just a simple diode? I ponder about the linearity of log/exp v.s the simple diode? Perhaps its OK from lets say +10 to+40 degC?! Im hoping its a diode/config tranny.... but..

author: David Hess
author_rank: Super Contributor
timestamp: January 28, 2018, 04:35:06 pm
content: The temperature coefficient of gain of a log/antilog circuit is calibrated using a +3300ppm/C resistor so maybe you are looking only at that element. Usually the resistor is grounded at one end.

author: SeanB
author_rank: Super Contributor
timestamp: January 28, 2018, 05:24:16 pm
content: Probably a NPN transistor with collector and emitter shorted together connected to substrate, and a series polysilicon resistor in series with the base to get the resistance required. Both have a tempco that is pretty close to what you describe there. If you want to emulate it as discrete parts you will find almost any small signal transistor will work, but the polysilicon resistor will be hard.

author: MT
author_rank: Super Contributor
timestamp: January 28, 2018, 08:10:26 pm
content: So to sum up, due to sensor nominal 2.5V output voltage one can assume a diode config'ed NPN tranny plus biasfor linearity/range and offset with a final slab of amplification, BJT VBE multiplier or so?Simple 5 cascaded diod configed trannies with a 3k resistor bias gives 2.49V but is that viable solution for a simple up biased temp sensor close to logging cirquit , no? assuming sensor biasing is through current mirrors rather then polysilicon resistors , perhaps? Sensor out voltage are spece'd from 2.2 to 2.8 with nominal 2.5VThe 0.8um process was suposedly Interdesign Inc (Hans Camenzind) "1980 databook 201 Analog IC Designs from Interdesign" , later sold to Ferranti/GEC Plessey. (i dont have the book and are no chip designer and knows very little about temp sensors ).
TempDoctor - Revolutionary Open Source Temperature Controller for Reflow Ovens - Page 1
Forum section: electronics / projects

author: dorin
author_rank: Contributor
timestamp: April 06, 2018, 02:55:29 pm
content: The topic could probably also fit in OHSW but I wasn't sure if the project actually qualifies for that badge.You might think oh no, not yet another reflow oven controller..But you've got to admit this one is pretty badass, it's a working example of clever front panel design and clever control algorithms.Details, firmware and design files:https://zenontech.wordpress.com/2018/04/01/tempdoctor-reflow-oven-controller/In terms of reflow performance, from my measurements (not so rigorously documented unfortunately) it turns out that no point on the PCB's is more than 7 degrees C off from the center oven thermocouple. That difference can happen when the whole oven is ramping up with more than 1 degree per second and of course thermal inertia is hard to overcome but when the oven temperature is stable (no ramping up or down) then all points inside are within 2 degrees from the center, which is more than good enough.If you have feedback or questions I'll do my best to reply, but I moved my career focus from hardware to software & AI so I definitely won't maintain / improve this project. Of course, anyone can fork the design and do whatever they please with it.
Temperature alarm for boiling milk - Page 1
Forum section: electronics / projects

author: matematik7
author_rank: Newbie
timestamp: November 27, 2016, 03:59:45 pm
content: Anyone who has ever boiled milk on the stove knows, that it has a nasty habit of overflowing. That is why I created the temperature alarm for boiling milk to be used my mother.The temperature alarm uses attiny841 microcontroller and DS18B20 to continuously measure the temperature of the milk and sounds an alarm when the temperature is over the preset alarm value.I’ve designed the pcb in KiCAD, etched the pcb at home and soldered it together.The case is made from 4mm plywood and the buttons are small pieces of wooden rod glued to a square piece of plywood so they can not fall out.More info:https://domen.ipavec.net/en/temperature-alarm/
temperature coefficent of a audio balun transformer? - Page 1
Forum section: electronics / projects

author: CopperCone
author_rank: Super Contributor
timestamp: January 18, 2018, 01:45:44 pm
content: Does anyone know what the typical temperature coefficient of a audio balun transformer might be?That is, how much the output signal amplitude varies per degree Celsius?

author: schmitt trigger
author_rank: Super Contributor
timestamp: January 18, 2018, 02:04:09 pm
content: All I know is that copper's resistance increases 0.39% per each degree C.I would not think that the steel core's properties would change very much.

author: CopperCone
author_rank: Super Contributor
timestamp: January 18, 2018, 05:09:24 pm
content: I am interested in the comparison of capacitors and inductors.I can very precisely make a push pull driver with opamps and thermally matched resistors. This can be coupled with two foil capacitors and the drift is the tempco of the capacitor. Its reactance will have a voltage drop proportionalto temp. Its approximately 160ppm/degree c.The capacitor can be made large to lower the effect of its reactance drop, however i am also very concerned about dc leakage, and dc leakage over temperature. This forces me to use foil capacitors, which are rather large past 10uf or so.I am interested in taking ppm measurements to make a choice.Should i focus on measuring steel laminated ones to get some sort of idea?My measurements on inductors lead me to believe they have a tempco of approximately 600ppm/degree c. This is worse then capacitors, so the reactance would need to be four times lower to match the performance of capacitors.Anyone got any numbers? Otherwise i need to make a tempco box.In that case, any suggestions on a good balun to test? Will the materials used in a common mains transformer be the same as an audio transformer? The type of steel?Also it looks like i need to meausure both dc resistance drift and inductance drift and correlate them

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: January 18, 2018, 06:11:58 pm
content: I'm sure there's some inductance and resistance change, but the output is determined by turns ratio. If you have low impedance drive, and don't load the output, it should be almost unaffected by temperature. You should read the manuals for precision ratio transformers like the old General Radio 1493. They don't talk about temperature at all, yet the things are good to less than a ppm and were recognized as primary standards by NIST.

author: CopperCone
author_rank: Super Contributor
timestamp: January 18, 2018, 08:50:36 pm
content: the load is unfortunately not high impedanceI guess that I am in uncharted territorySince there is mutual coupling between the primary and secondary, must its drift be evaluated too?Easy enough to setup a LCR meter to measure a winding across a temperature shift, but could this value be used or do I need to use the test signal? I think that there are some losses that might effect it more. Fringing loss comes to mind but can it just be ignored for the sake of stability?
temperature compensation strain gauge placement on windmill blade - Page 1
Forum section: electronics / projects

author: embedded.world@aol.com
author_rank: Contributor
timestamp: March 29, 2014, 05:44:25 am
content: I have to measure strain on blade of windmill. We have placed 3 strain gages on each blade. I have attached a pictureI am using Quarter-Bridge Type II configuration as below link shows:http://www.ni.com/white-paper/4172/en/#toc5In this 1 gage is active while other is dummy.Now I have question regarding dummy gage.1. How can I place dummy gage on blade so that it don't get affected by strain on blade & in same time maintain close thermal proximity with active gage.Edit:2. Or anyone having experience in this topic who can suggest better alternative. Gage have to be 3.
Temperature controlled fan project for beginners - Page 1
Forum section: electronics / projects

author: queennikki1972
author_rank: Regular Contributor
timestamp: September 22, 2019, 04:32:04 pm
content: I just wanted to say that this is a good project for beginners. I really enjoyed it. I am more curious about the specs of the NTC 472 (4.7K) Thermistor.. surface heat tolerance. And if other types of thermistors could be used in the same circuit, such as mounting on a large heat sink with shrink tubing and a screw.Here is a link to the thermistor used.https://www.ebay.com/itm/20-Pcs-NTC-Thermistor-Resistor-NTC-MF52AT-4-7K-OHM-5-B-3950K-1/392365363405?hash=item5b5acc50cd:g:WWcAAOSwTm1dQ5w5:sc:USPSFirstClass!76116!US!-1

author: soldar
author_rank: Super Contributor
timestamp: September 22, 2019, 06:40:33 pm
content: As you say, an easy project for a beginner. The comparator turns the fan on/off.I would prefer a proportional control where the speed of the fan is proportional to the temperature deviation. This allows the fan to run continuously and more slowly and quieter rather than stop and then blast.

author: Zero999
author_rank: Super Contributor
timestamp: October 02, 2019, 09:40:41 am
content: Quote from: soldar on September 22, 2019, 06:40:33 pmYes, that's a good idea, but it will no longer be a beginner project. Proportional control of fans will save power, but for something small, it might not be worth the extra complexity.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 02, 2019, 10:33:54 am
content: Proportional control is a little more complicated, as it needs a suitable gain factor. As this is only 1 value to get right one could still go for try and error.Even the simple on/off control may want some hysteresis to avoid to frequent on/off. So even this solution may need 1 parameter to adjust.

author: soldar
author_rank: Super Contributor
timestamp: October 03, 2019, 08:13:15 am
content: Quote from: Zero999 on October 02, 2019, 09:40:41 amMy concern is noise, not power consumption.Copying a proven design should not be complicated at all.Even a simple design should not be complicated.Really simple is to have two or three steps. Take a 12 V fan and run it at 0 V, 6V, 12 V depending on temperature.But with an Op amp it should be very easy to design a true proportional control.
Temperature measurement from long distance - Page 1
Forum section: electronics / projects

author: Dhanushka
author_rank: Regular Contributor
timestamp: December 10, 2019, 06:36:26 pm
content: Dear all,I am now working in a project to gather temperature data of a fire from certain distance (at least 3 m away) with covering area (at least 3 degree solid angle). But I was planning to use IR non contact thermometers. But I am confusing whether it is suitable or not? So, can anyone tell me that are these sensors suitable or are there any sensors which could be used for long distances and wide area coverage(including part/model numbers).Thanks

author: tggzzz
author_rank: Super Contributor
timestamp: December 10, 2019, 06:55:45 pm
content: Old rhyme...Langley invented the bolometer,A very fine sort of thermometer.It can measure the heat,Of a polar bear's feetAt the distance of half a kilometer.
Temperature relgulator not working - Page 1
Forum section: electronics / projects

author: NightRider92
author_rank: Contributor
timestamp: February 08, 2025, 08:17:30 am
content: Hello everyone,I made a PCB that is supposed to be a temperature regulator(ESP8266 goes into the sockets) but the problem is that the PCB is not working at all.It it supposed to use 5V USB power supply that should trigger the relay(activated by transistor) but none of the things I tried seems to be working.Neither does relay activation works, nor temperature readingsfrom the sensor.The PCB was made and assembled by JLCPCB.What did I do wrong?Could someone help me, please?

author: Thomas
author_rank: Regular Contributor
timestamp: February 08, 2025, 11:13:35 am
content: You haven't connected the sensor data signal (DQ) to the ESP8266.I suspect you're thinking the signal is connected to pin 14 of the ESP8266, but it isn't. Pin 14 is connected to VDD.Move the signal going to pin 14 to the other side of R2 and you might get better results.

author: NightRider92
author_rank: Contributor
timestamp: February 08, 2025, 04:05:29 pm
content: Ooops ... I haven't noticed that.So when i connect it, everything should beworking correctly?

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: February 08, 2025, 04:24:22 pm
content: If possible, simulate your circuit in proteus. And though It's unlikely to receive a faulty PCB from JLCPCB, I think it's better to check with a multimeter to see if there is an unwanted short circuit or a broken trace somewhere.

author: NightRider92
author_rank: Contributor
timestamp: February 08, 2025, 04:53:22 pm
content: I haven't used Proteus but I'll try.Thank you.But as I asked, could you tell will it work just by looking at the circuit right now? (Of course, if I connect pin14)

author: NightRider92
author_rank: Contributor
timestamp: February 11, 2025, 10:29:09 pm
content: I made some corrections. Like I said, I will be using ESP8266.Question is: should this work right now? I'm really not much into electronics and stilllearning and spent like 70 USD on two faulty PCB's (JLCPCB) because I madesomething wrong.Also, do i connect the route tracks (manually) in KiCad accordingto the blue guiding lines (on the screenshot) or is there a possibility that KiCad could getsomething wrong? Should I double check it?Some help would really be appreciated.Thanks for the effort in advance.

author: Thomas
author_rank: Regular Contributor
timestamp: February 12, 2025, 11:53:38 am
content: You still haven't connected anything to the sensor data pin (other than pullup). J2 pin13 is connected to 3V3, which I think is not what you want.What's Vin? 5V from USB? You have connected that to 3V3 (through PWR_FLAG), which is probably not a good idea.The blue lines (they are called airwires) will be correct if the footprints are correct and the schematic is in sync with the board. Go to the schematic and pressTools -> Update PCB from Schematic.Not a bad idea to double check it anyway.
Temperature rise in current shunt / resistor - Page 1
Forum section: electronics / projects

author: JJalling
author_rank: Unknown
timestamp: July 28, 2013, 01:58:28 pm
content: Hi,I plan to use a Vishay WSL3637 (http://www.vishay.com/docs/30099/wsl3637.pdf) resistor as a current shunt. The current will be in the range 0-4A and i want the measurement to be as accurate as possible.Can anybody help me with ball-park figures of the expected temperature rise in the resistor?I plan to use a value of 10mOhm, which gives me a powerloss of about 200mW at full current.BR Jonas

author: robrenz
author_rank: Super Contributor
timestamp: July 28, 2013, 02:11:42 pm
content: It will depend an a lot of other variables that are hard to nail down. I would suggest a cold resistance measurement with a short pulse of the 4A and document the voltage drop. Then operate it a 4A continuous when it is in its final configuration with enclosure etc. now measure the voltage drop. you now know the delta V that occurs from cold to max temp. Now you can linear interpolate for in between currents or do tests like that at whatever amperage steps you like to get other values. But these will only be steady state values.

author: richard.cs
author_rank: Super Contributor
timestamp: July 28, 2013, 02:17:50 pm
content: From the datasheet max power is 3 Watts, then look at the de-rating graph. The full 3W is acceptable up to 70C and then it's linearly de-rated to zero power at 170C. From this we can conclude that the maximum temperature the resistor can safely handle is 170C and that it will reach that temperature with 3W if the ambient temperature is 70C. 3W therefore causes a 100C temperature rise and 200 mW should be proportionally smaller at 7C.With this type of resistor actual thermal resistance (and hence temperature rise) will depend on how it's mounted. The datasheet is usually written to make the resistor look as good as possible so in absence of other information you should assume it means on an infinite groundplane (in reality one large enough the edges don't get hot). With realistic PCB design expect perhaps double the calculated temperature rise.
Temperature rise in the inductor? - Page 1
Forum section: electronics / projects

author: Gowda1
author_rank: Contributor
timestamp: February 09, 2021, 05:35:02 pm
content: Hey,I have a customized inductor which is of E70 core. I would like to calculate the temperature rise in the inductor considering ambient temperature as 30degree celcius. I have a losses around 80W, core loss=20W, Ac copper loss= 60W. I would like to calculate the maximum temperature in the core with 80W. Please let me know if anyone come across this, any link/literature would be great too. Thank you. Link for the datasheethttps://www.tdk-electronics.tdk.com/inf/80/db/fer/e_70_33_32.pdf

author: EmmanuelFaure
author_rank: Regular Contributor
timestamp: February 09, 2021, 06:03:31 pm
content: Too much! A computer CPU dissipates about 50-100W, and it requieres a heatsink with about ~0.5m² of total fin surface in forced convection to keep it under 70°C.In comparison your inductor will have a total external surface of ~0.011m² (Cf core datasheet). With 80W of losses you'll melt it.
Temperature sensor TC1047A RF susceptibility - Page 1
Forum section: electronics / projects

author: AndersJ
author_rank: Frequent Contributor
timestamp: November 07, 2024, 01:44:39 am
content: I have a Microchip TC1047A, analog out, SOT23 temperature sensor.It fails radiated immunity tests at 430 and 150 MHz, and other frequencies.I have decoupled and filtered it in every possible way.The only working fix is to shield it.I have replaced the sensor with two resistors that generate a suitable output.The susceptibility goes away, so I believe the sensor is RF-sensitive.Any thoughts?
Temperature sensors probes and communication interfaces - Page 1
Forum section: electronics / projects

author: Nikos A.
author_rank: Regular Contributor
timestamp: September 15, 2021, 08:39:02 am
content: Hi everyone,We are in the process of gathering the system requirements and specifications for a design. One of the aspects is that we need to provide two temperature sensors (probably probes) to measure the water pipe surface temperature and maybe the water temperature inside the pipes as well. I am looking for temperature probes but I didn't have had a lot of lack. The most commonly used sensor I found is the DS18B20 that is usually sealed inside a metal probe to provide waterproofing as well.Do you have any suggestions for temperature probes and the communication interface?Thanks

author: rpiloverbd
author_rank: Regular Contributor
timestamp: December 22, 2021, 12:46:34 pm
content: I think using two DS18B20 waterproof sensors will solve your purpose. One for the water surface, another for the inner side of the pipe. DS18B20 supports one-wire communication. It is possible to use and collect data from two DS18B20 simultaneously using an Arduino or suitable microcontroller. You can get some idea from here:https://www.theengineeringprojects.com/2016/03/interfacing-multiple-ds18b20-arduino.html

author: jmelson
author_rank: Super Contributor
timestamp: December 22, 2021, 11:57:13 pm
content: Quote from: Nikos A. on September 15, 2021, 08:39:02 amI used AD590JH sensors. These are current sources that pass current proportional to absolute temperature. I found they can be blown out by local lightning pulses, so glue them to silicone insulating pads that are then glued to the pipes. The external tempweature of copper pipes will be VERY close to the temperature of the water within.Jon

author: Nikos A.
author_rank: Regular Contributor
timestamp: December 30, 2021, 08:45:22 pm
content: Thank you guys!!
Temperature tolerance of an LED regulator? - Page 1
Forum section: electronics / projects

author: Artlav
author_rank: Frequent Contributor
timestamp: August 22, 2014, 08:30:24 pm
content: I made an LED driver, out of ZXLD1360 converter chip, and want to know how much power i can get out of it.Which essentially boils down to how hot can it get safely.Appearance:,Layout:At highest it can go, 0.4A LED current, the driver gets to 90-95*C.And i don't know how to feel about it.On one hand, it sounds hot.Very damn hot.On the other hand, the chip is rated for 150*C junction temperature and 1W dissipation.Which is within limits.If i counted right, it's dissipating no more than 0.4W.At that dissipation the maximum ambient temperature is 85*C.It is mounted within a 60*C LED heatsink.Also within limit.I ran it for a few hours at that rate, and it works just fine.So... Is it ok after all?Being at 95*C appears to be well within spec, but it does not feel right to me.

author: DanielS
author_rank: Frequent Contributor
timestamp: August 22, 2014, 09:02:22 pm
content: If the chip's surface temperature is 95C and the chip has a 40C/W junction-air thermal resistance (the junction-case thermal resistance is only something like 1C/W, which is effectively negligible), the junction temperature would be around 111C.If you want to reduce the chip's temperature, you might want to put a thermal interface pad between the PCB and heatsink behind the chip, and do some via-stitching between the top-layer's ground plane and the bottom-layer to help heat through to the heatsink.
Tempo - an stm32 based temperature logger  - Page 1
Forum section: electronics / projects

author: maor
author_rank: Contributor
timestamp: September 30, 2018, 03:34:28 pm
content: hey,first serious post here,glad to share my first hobbyist project, tempo.enjoy.https://youtu.be/xEt-9RTFhMY

author: t1d
author_rank: Super Contributor
timestamp: October 01, 2018, 09:58:03 am
content: Nice job.

author: martinjaymckee
author_rank: Contributor
timestamp: October 02, 2018, 07:24:50 am
content: Very well done on developing the Tempo. The functionality you managed to fit into it seems very well thought out. I especially liked the overview of the development process you gave. It's important to for people to see how an idea evolves and grows. You presented it very well.Cheers,Martin Jay McKee

author: Rerouter
author_rank: Super Contributor
timestamp: October 02, 2018, 12:48:49 pm
content: In order to reduce power consumption further, I've many times pulled tricks like using an external SPI RTC to wake my device from power-down with a 1 second interrupt, this way everything is off until that pulse, and the RTC chews through less than 1uA to accomplish it.Then my device wakes up, does all its magic in under 1ms, including writing to memory, then going back to sleep, and for sensors that have a longer conversion time, well that interrupt pulse has 2 edges, spaced 1/64 of a second after, So you set up your conversion, go to sleep, wake on the other edge of the interrupt and store the value before shutting things down for the rest of the second,2mA idle current seems wrong, Is that the display chewing that??

author: maor
author_rank: Contributor
timestamp: October 02, 2018, 06:37:33 pm
content: Quote from: Rerouter on October 02, 2018, 12:48:49 pmHey,The current is mostly pulled by the micro, I turn off the lcd when low power mode is on...I might be able to reduce the idle current even further.I set a timer and put the micro in wait for interrupt mode (WFI) so that means I can turn off all of the APB clocks and lower the power even more.I'll test that and get back to you.
TENS circuit problem - Page 1
Forum section: electronics / projects

author: Kakashi
author_rank: Contributor
timestamp: February 26, 2017, 09:34:08 pm
content: Several years ago I decided to build a TENS circuit, but sadly failed and the circuit bit the dust in the drawer. Recently found it and want to give it a shot at "repairing"(never really did work for me, though...)The problem is that at the output I only get ~10-20 volts, nothing more. And I should get the full 80V.I have tried different IR2155/53 but to no avail.I get 0-80V after D1, no problems there.I just can't get the IR chip to pump the correct voltage at the output, it's somehow locking the MOSFET's.Changed the 100nF cap at pin 6 to a higher capacitance but still no change.Here is the website, also it was mentioned in the silicon chip magazine.http://kisu.tripod.com/Here is the schematic from that site+SC:

author: Benta
author_rank: Super Contributor
timestamp: February 26, 2017, 10:10:37 pm
content: QuoteWith what are you measuring? Only an oscilloscope will provide a sensible result. With a DMM you won't measure anything, the output is pulsed.The schematic looks OK and should work.

author: Kakashi
author_rank: Contributor
timestamp: February 26, 2017, 11:03:14 pm
content: Quote from: Benta on February 26, 2017, 10:10:37 pmTrms DMM and Oscilloscope. I think I need to rebuild it from scratch.

author: Seekonk
author_rank: Super Contributor
timestamp: February 26, 2017, 11:33:42 pm
content: I would measure the voltage between 6 & 8. It sounds like you don't have enough high side drive. Since you changed the cap, leaky diode? That could be hard to measure. Replace diode would be the easiest thing. Do you actually have voltage going to the chip? 10V sounds very low. Many of these chips shutoff at about that voltage. Raise up voltage zd2 with a couple of diodes.Checked data sheet. Low voltage is likely your problem, raise to 12V minimum.

author: Kakashi
author_rank: Contributor
timestamp: February 28, 2017, 09:01:28 pm
content: Quote from: Seekonk on February 26, 2017, 11:33:42 pmIt seems that's the case. In the original schematic on that website(page4), there isn't any 10V zener diode on the other hand Silicon Chip's has it.
Tented via under ground pad - Page 1
Forum section: electronics / projects

author: tiborsimon
author_rank: Contributor
timestamp: August 07, 2014, 10:09:44 pm
content: Hi!Is it a good idea - in case of not enough pcb room - to shrink the ground pad of a QFN footprint, and use tented vias to route tracks in the generated free space? Furthermore, I am going to route Vcc in this way.https://www.dropbox.com/s/ze6bzsvacwluw7h/Screenshot%202014-08-08%2000.01.32.png

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 08, 2014, 12:47:45 am
content: No.

author: suicidaleggroll
author_rank: Super Contributor
timestamp: August 08, 2014, 02:16:54 am
content: Solder mask should be used to aid soldering, not as a last resort to prevent fire-inducing short circuits when your components are placed.If your board can't possibly work without solder mask, you need to re-think the layout.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 08, 2014, 08:09:55 am
content: I wouldn't recommend counting on soldermask...I've actually seen the stuff hold off a solid 700V before. I've also seen it arc through on the same point.Vias occasionally seem to get partially or fully plugged, or remain open in such a way that the mask either comes right up to the edge, or looks like it flowed by capillary action in such a way that the thickness goes from nominal over most of the via pad, to nearly zero at the very corner (the copper is nearly shining through on the inside rim).I do expect it would be acceptable to do if you have plugged vias. This requires an extra step and is probably a "custom" run ($$), by a capable board house. I have an example on an old laptop motherboard: all vias are coated and plugged, so that the entire board looks shiny and uniformly green. If you look closely, there's actually a little bit more goo over every via, which feels flat but doesn't quite look flat. Copper is not visible (no edge problems), except where they wanted it to be (which is odd, as this particular board is not gold plated or tinned; a number of mounting holes have bare copper pads/plating, no idea why they chose that).Tim

author: tiborsimon
author_rank: Contributor
timestamp: August 08, 2014, 07:46:09 pm
content: Thank you guys for the answers. I am going to redesign my circuit
Tenting Vias to Reduce Thermal Pad Solder Starvation - Page 1
Forum section: electronics / projects

author: HenryM
author_rank: Newbie
timestamp: February 15, 2020, 12:58:36 pm
content: A board we recently sent out for production had some tented vias in a thermal pad under two separate ICs. One of the IC's had 10mil hole vias and the other had 30 mil hole vias. They asked for clarification basically saying that surely we didn't want any of those tented as we had a fab note indicating that the tented vias did not need to be plugged, so why even tent them?The 30 mil holes I understand, those can't really be tented reliably. I asked them to use a 10 mil drill there instead and leave the tenting in place in all vias where specified in the gerbers.So, my question is, does tenting a 10mil hole via found in a thermal pad underneath an IC accomplish anything? Or would the solder just bridge across the hole and go no where.
Terminal assignments of 4wire resistance measurement on bench DMMs - Page 1
Forum section: electronics / projects

author: leonerd
author_rank: Regular Contributor
timestamp: April 02, 2018, 03:27:17 pm
content: Almost every bench DMM I've seen that does 4wire resistance measurement, puts the current source on the terminals are used for volt measurement in DCV mode, and sense on some separate ones. This suggests that the meter has internal switching to be able to connect the ADC measurement system to either pair of terminals, and multiplex that with the current source on the first set of terminals.Does anyone know why that is? I'd have imagined it would be easier to reuse the main voltage-sensing terminals as the sense input, and put the source on its own dedicated second pair. That way there's no multiplexing; you simply have to enable a current source on the second pair and continue to measure voltage on the first pair.

author: ejeffrey
author_rank: Super Contributor
timestamp: April 03, 2018, 03:30:02 am
content: You still need multiplexing if you want to support 2-wire and 4-wire ohms.