hybridfree/eevblog-posts huggingface dataset:
The Story of the Red Special - The Queen Story Continues - Page 1
Forum section: electronics / projects

author: German_EE
author_rank: Super Contributor
timestamp: June 23, 2017, 02:47:27 pm
content: Some time ago I posted a link to Hackaday that told the story of the 'Deacy' amplifier. Well, now we have the story of the Red Special.http://hackaday.com/2017/06/13/the-red-special-brian-mays-handmade-guitar/Have fun

author: DBecker
author_rank: Frequent Contributor
timestamp: June 23, 2017, 05:09:02 pm
content: Wow, another fascinating story.I initially thought "what could be interesting or unique about a guitar amp?". Then I read the amp story and immediately tied it to the unique sound of of the songs I grew up with. (Queen was my favorite band as a young teen. I had their albums on vinyl at home and 8 track for family trips. It was years before I realized the significance of their name -- I now wonder what my parents thought when I mostly listened to Queen and the Rocky Horror soundtrack.)I didn't think the guitar story could come close, but it was almost as fascinating. I have a new level of respect for a band that made their own instruments, and worked with their 'flaws' to produce innovative, memorable music.

author: German_EE
author_rank: Super Contributor
timestamp: June 23, 2017, 06:29:19 pm
content: Opinions will differ here but I put Brian May at the same level as Clapton and Hendrix. All three of them are Masters of their art

author: rsjsouza
author_rank: Super Contributor
timestamp: June 24, 2017, 11:40:35 am
content: Excellent story! This reminded me that Eddie Van Halen also made his own guitars.http://www.popularmechanics.com/technology/a15615/how-eddie-van-halen-hacks-a-guitar/
The SynthiMuse - shameless self-promotion. - Page 1
Forum section: electronics / projects

author: ninthlamp
author_rank: Newbie
timestamp: February 27, 2017, 01:55:07 am
content: Hi AllMy first post with a request for comments on my nearly completed product.www.synthimuse.comIt's a MIDI composer that has an 'analog' user interface modelled on the venerable synths of the 1970'sIt has :A built-in microphoneAn audio inputFilters to discriminate the pitch of the audioAn analog white noise generator for genuine randomness.Standard MIDI Input/OutputUSB MIDIA couple of microcontrollers. One dedicated to USB MIDI, the other handling the main functions.A later variant will have an analog output to be able to drive 1V/Octave analog synthesizers.Your observations and comments welcomed.Many thanks.

author: mubes
author_rank: Regular Contributor
timestamp: February 27, 2017, 08:44:46 am
content: Hi,I like the design of your panel - how did you realise that? Front panels and casings in general are a perennial problem for me...DAVE

author: ninthlamp
author_rank: Newbie
timestamp: February 27, 2017, 03:02:37 pm
content: Hi DaveThanks for the compliment.The panel design was done in 'Inkscape' before being imported in to Adobe Illustrator because it was the format needed by the enclosures manufacturer.I highly recommend 'Inkscape'. It does so much and it's open source.
"The Thing": Homemade FPGA + STM32 board, "Multicomp" compatible - Page 1
Forum section: electronics / projects

author: Just4Fun
author_rank: Contributor
timestamp: February 03, 2019, 05:52:06 pm
content: Hi all,this is "The Thing", an homemade FPGA board with an Arduino STM32. It is also "Multicomp" compatible ("Multicomp" is a modular VHDL design to "run" some famous retro 8 bit CPUs made by Grant Searle) giving the option to "run" easily a VHDL SOC with a Z80/6809/6502 CPU and I/O, including HD (on SD) and a color VDU. Just to start to play with HDL languages and softcores...Here The Thing in action "running" a Multicomp Z80 with CP/M 2.2 as OS:https://youtu.be/j8qfqlEfJm8More infohere.Regards.J4F

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 03, 2019, 06:14:01 pm
content: Thanks for sharing.Just a thought, but do I see a Cyclone II? It's a 14-year old device...I don't really know how much longer Intel is willing to maintain this series, now that it's Intel.Any reason you didn't select something a tad more recent? I don't know the Altera line well, but something that seems roughly equivalent but already significantly more recent at an equivalent price would be the EP4CE6E22C8LN (Cyclone IV). The Cyclone V seems more expensive. Maybe the new MAX10, but it would probably be a bit more expensive too although I don't know how they would compare to a Cyclone II.Or maybe it's part of the retro thing, in which case don't mind me.

author: tsman
author_rank: Frequent Contributor
timestamp: February 03, 2019, 06:29:25 pm
content: Looks to be becauseMulticompuses a cheap EP2C5T144C8N board from China. The Thing is using the same Cyclone II for compatibility.

author: Just4Fun
author_rank: Contributor
timestamp: February 03, 2019, 06:31:42 pm
content: Quote from: SiliconWizard on February 03, 2019, 06:14:01 pmRight. You "must" use no more than Quartus II v13sp1 for that.I have chosen that because it is cheap and you can find it easily "around". More, it has only two supply voltages, so it is easier to route for a 2-layer PCB.I have already some Cyclone IV on my bench, and I'll use them in a next version for sure......but before some VHDL fun...

author: Just4Fun
author_rank: Contributor
timestamp: February 03, 2019, 06:36:43 pm
content: Quote from: tsman on February 03, 2019, 06:29:25 pmYep. Anyway I've found some Cyclone IV Multicomp enhanced versions. So I'll use those in the next Cyclone IV version...

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 03, 2019, 06:38:51 pm
content: Alright then!
The third hand - Page 1
Forum section: electronics / projects

author: KedasProbe
author_rank: Frequent Contributor
timestamp: July 18, 2014, 07:00:05 am
content: The third hand you need during soldering.This is not it, but it's a start

author: Artlav
author_rank: Frequent Contributor
timestamp: July 18, 2014, 10:12:12 am
content: Interesting.However, the motion of the fingers look quite chaotic.I wonder how real-world useful that would be.

author: con-f-use
author_rank: Unknown
timestamp: July 18, 2014, 11:39:20 am
content: And how real-world expensive.

author: alanb
author_rank: Frequent Contributor
timestamp: July 18, 2014, 11:44:49 am
content: Something related by Ben Heckhttp://youtu.be/S_J2_uI8kyEhttp://youtu.be/tSWzYG6eigA

author: zapta
author_rank: Super Contributor
timestamp: July 18, 2014, 02:29:19 pm
content: Quote from: KedasProbe on July 18, 2014, 07:00:05 amYou need to be careful with these extra attachments ;-)

author: jay
author_rank: Regular Contributor
timestamp: July 19, 2014, 05:57:59 am
content: I already have 3 or 4 hands when needed.. I simply ask my wife to lend a hand
v!OtQ54%9aQ274Nb^O@!h*Rs153X2!eEDo4K3!Sg - Page 1
Forum section: electronics / projects

author: APTechnologies
author_rank: Newbie
timestamp: July 25, 2020, 11:21:34 am
content: -

author: RJSV
author_rank: Super Contributor
timestamp: August 01, 2020, 01:01:10 am
content: Hi, Nice to see that, but need a couple days before have much time.First helpful thought goes to the LED power consumption, if always ON it matters more: Wanted to mention the 'white emitting' LEDs salvaged from a Christmas snow related twinkle lights or icecycles (sic) and measured current was exceptionally low!Something approximately 30 uA. Voltage of system is not directly relevant. Many LEDs tend to operate higher, say approaching one mA, or greater. That's 30 times less, but might be hard to get all RGB where you'd like.How about use the most efficient (color) and just have an RGB set-up for a background disk. Plus, adaptive or set-able brightness, for better looks, softer or brighter, as you please... More comments later, thanks

author: OM222O
author_rank: Frequent Contributor
timestamp: August 01, 2020, 08:36:30 am
content: One major improvement I can think of:The screws look ugly, you can avoid them by moving the lip which the PCB sitst on, to the top side rather than the bottom side. if you're worried about touching it which rotates it around, the simply add a bit of glue to the lip (very small amount!) and put the PCB in place, let the glue dry and bam. resin epoxy usually works well for this application (not the UV curable ones!).You can also add a second lip above the PCB which will house a glass for a more professional look. I'm not sure about standard sizes of watch glass, but I'm sure you can easily google it.I spent 2 minutes in CAD (cardboard aided design) to make a cross section of what I mean. the black part is the main housing with the 2 lips, blue is the glass which sits on top of the upper lip, green is the PCB which sits on the bottom lip and the grey part is the backing which is usually screwed in place but I'm not sure how well 3D printed threads work, you can experiment with different things.

author: Renate
author_rank: Super Contributor
timestamp: August 01, 2020, 12:15:20 pm
content: I would have preferred the LEDs in a strict 4x4 (without the gap).If you have to have screws, rotate them 45 degrees so they visually have more clearance.I would have hours on top, 8 on the left, 1 on the right.Single color would be fine for many and make a smaller watch possible.But this is besides the point, I'd never wear a watch.I did build a 4x4 clock 40 years ago.
The ULTIMATE Electrical Engineers Toolkit - Analog Designer's Edition - Page 1
Forum section: electronics / projects

author: w2aew
author_rank: Super Contributor
timestamp: April 01, 2022, 12:34:02 pm
content: Enjoy!

author: moffy
author_rank: Super Contributor
timestamp: April 01, 2022, 12:45:20 pm
content: Wish it was true.

author: rstofer
author_rank: Super Contributor
timestamp: April 01, 2022, 01:35:37 pm
content: That's a cool video, thanks for making it.

author: Terry Bites
author_rank: Super Contributor
timestamp: April 01, 2022, 02:01:11 pm
content: Can you create a negative under unity device that drives a brown light bulb?I'm still trying!

author: rsjsouza
author_rank: Super Contributor
timestamp: April 01, 2022, 02:54:07 pm
content: That is a nice bit of toolkit! Worth every penny!

author: MK14
author_rank: Super Contributor
timestamp: May 12, 2022, 11:24:49 pm
content: Great Video!
The ultimate SMD marking codes database - Page 1
Forum section: electronics / projects

author: isometrik
author_rank: Regular Contributor
timestamp: October 06, 2021, 10:07:30 pm
content: The folks at Hackaday posted an article today that provides a link to "The ultimate SMD marking codes database". I haven't yet had the time to check every entry for completeness, but I will definitely bookmark the database's URL.I hope it will prove to be useful to the community.Hackaday article:https://hackaday.com/2021/10/06/decoding-smd-part-markings/The ultimate SMD marking codes database:https://smd.yooneed.one/

author: mayor
author_rank: Regular Contributor
timestamp: October 07, 2021, 11:04:28 am
content: Very cool, thanks.
The VCO's input goes up but the output is stable. - Page 1
Forum section: electronics / projects

author: misad
author_rank: Newbie
timestamp: December 02, 2018, 08:44:20 pm
content: Hello, I try to design a DPLL and its output successfully locked at 500Mhz. But the PFD's up signal always there and the charge pump works all the time. The very strange thing is that, the output keeps 500Mhz. I think it's because the Divde-by-10 out is always lag than the input signal. Can I do something eliminate the UP signal and make VCOin stable?

author: Benta
author_rank: Super Contributor
timestamp: December 02, 2018, 09:28:00 pm
content: Disclaimer: I've only worked with analog PLLs, not DPLLs. But the mathematics are the same.First, congratulations on a stable lock.But it does look odd, I agree.Normally, I'd expect the counter output (lowest trace) to align with the reference input (top trace), so divider delay shouldn't play a role in the loop.Also, the "UP" and "DN" pulses would be aligned with the rising/falling edges of the reference input.Is there some kind of "filter leakage" in the loop?A block/system diagram of the PLL would help.

author: misad
author_rank: Newbie
timestamp: December 02, 2018, 09:44:24 pm
content: This is the block diagram of my DPLL. I don't know what's the filter leakage...

author: Benta
author_rank: Super Contributor
timestamp: December 02, 2018, 09:59:25 pm
content: We need a bit of clarification: when you say "DPLL", do you mean digital PLL, as in implemented with an MCU or DSP?

author: misad
author_rank: Newbie
timestamp: December 02, 2018, 10:28:14 pm
content: I mean the PLL build by MOS transistors.. The Cap or the Res are all implemented by MOS transistors.

author: Benta
author_rank: Super Contributor
timestamp: December 02, 2018, 10:39:13 pm
content: So it's not a DPLL, it's an analog PLL.I suspect your HF_LoopFilter cap has a leakage to ground, which would explain your results. Try modeling with an ideal cap.

author: misad
author_rank: Newbie
timestamp: December 03, 2018, 04:49:50 am
content: I use the analog Cap, but VCOin still goes up... I zoom in the output frequency waveform and see it's not exact 500Mhz. Is it possible this is because the VCO, since I use the ring oscillator, it's hard to generate a stable 2ns(period), 50% duty cycle wave...
There should be a smarter way to drive 9 PWM LED with only 1or3 PWMs available.. - Page 1
Forum section: electronics / projects

author: Houseman
author_rank: Regular Contributor
timestamp: November 24, 2016, 10:56:23 pm
content: Dear all.For my school project I need to simply drive with Arduino 9 PWM strip LED (maximum 500 mA per strip) that goes on and off independently and has a sort of dimming effect on each channel.Internet is full of PWM driving MOSFET schematics that optocuples the single output and drives the LED strip through an IRF 540; this should not be a problem..But now the question: my arduino uno has only 3PWM outputs available, and it should, I think, be very pity or better a waste of resources to use an arduino MEGA only because has 14 PWMs.So I was thinking of using 2 demultiplexer chips (HEF4051B) using only 4 digital pins (yes, 111+001…sigh), making a 4x4 cross matrix and use only 9 of them in order to enable the 9 different outputs.But now… how to connect the PWM outputs? should all the optocoupler be enabled by the chip? each LED brightness should be controlled individually. How to use the Persistence of Vision in order to allude they are all on?Any help would be very appreciated. Just give me a hint, one direction, and I will try it by myself.Best regardsThank You

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 24, 2016, 11:41:43 pm
content: Have never tried it myself but Google immediately spits out some results:http://www.instructables.com/id/Multiplexing-with-Arduino-and-the-74HC595/http://electronics.stackexchange.com/questions/73087/multiplexing-avr-atmega328-pwm-within-interrupts

author: VoidsWarranties
author_rank: Contributor
timestamp: November 25, 2016, 02:14:45 pm
content: The tlc5940 has 16 hi res pwm outputs but uses the arduino's to drive it. I have used it for driving 7 segment led displays since it has built in current limiting. There is already an arduino library for it.Note that the tlc5940 does not multiplex the outputs.Sent from my iPhone using Tapatalk

author: Fungus
author_rank: Super Contributor
timestamp: November 25, 2016, 04:00:42 pm
content: Quote from: Houseman on November 24, 2016, 10:56:23 pmAn Arduino Uno has six hardware PWM outputs - the pins with a '~' drawn next to them.If you're handy at programming you can do software PWM on any pin. Just just turn on the pin, count down, turn it off again.

author: SL4P
author_rank: Super Contributor
timestamp: November 25, 2016, 07:34:36 pm
content: If your code has enough spare cycles, i've built a 72 channel 'SOFTWARE' PWM driver using TPIC595 drivers (4 pins), but depending on how smooth you want the PWM 'glides' to be, you may want drop to a lower number.This worked great for RGB chaser and pulse/flash/comet-trail effects.Other shift registers equally relevant.
Thermal analysis - Page 1
Forum section: electronics / projects

author: RobEE
author_rank: Contributor
timestamp: May 12, 2017, 11:38:12 am
content: I am looking for a way to do a thermal analysis of an electronic system to determine if the heat dissipated by the electronics will be enough to require additional cooling to prevent the electronics from going above their max rated temperature. If I have a rack (not a 19" rack, but custom racks/shelving) filled with electronics, and I know the power requirements for each electronic box and data on each boxes internal fan (if it has one), and the rack is exposed to ambient air; is there a way to determine the temperature rise around the boxes from the heat they dissipate? How would this change if the rack was enclosed? Or only partially enclosed?I work for a small company so we can't afford any expensive thermal analysis software, or a full-time thermal engineer. We are looking for a way to at least do a ball-park thermal analysis. Any help will be greatly appreciated.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: May 12, 2017, 03:44:04 pm
content: You might try the free student edition of Quickfield. There have been some thermal analysis articles in EDN and other places over the years, with the earlier ones having some programs and formulas. Probably impossible to find now was the March 1985 issue of Electronic Packaging & Production, pg. 80-84 by Paul R. Conigliari. It had an error, but I have the corrected basic code that could easily be ported to VB or something. PM me if you want it.
Thermal Camera Analog Video Output - Page 1
Forum section: electronics / projects

author: Trex
author_rank: Newbie
timestamp: January 05, 2016, 01:48:58 am
content: Hi all,I have been working on a project which is a heads-up display for firemen which displays various useful data such as temperature, time, and biometrics to each firefighter via a near eye display. Eventually the goal is to have an option for a thermal video feed to be displayed however this is giving me some troubles because of the price of even the worst cameras.The near-eye display was pulled from a pair of video glasses found herehttps://www.adafruit.com/product/1452The display only takes an analog video input (PAL/NTSC). What I want to do is be able to simply switch between the data display feed from my micocontroller and the thermal video feed but in order to do this I need a camera with an analog video output.After much searching I have found a breakout with just what I want. It uses a Flir Lepton camera and then a couple of passives and several chips to create the analog video output from the Lepton's SPI video interface. Link is belowhttp://www.flytron.com/thermal-cameras/303-dronethermal-micro-uav-thermal-camera.htmlThe only problem with this board is that it costs a whopping $450 which just isn't in the budget so I want to either reverse engineer this board and make a clone or just create a new one from scratch.The Flir Lepton module can be found on digikey for only around $183 which is in the budget and I know I can easily get the board and other periphery parts for under $50.So now here is my dilemma. I have tried to find the parts based off of the part codes I can see from the pictures on the board's shop page but have had no luck at all. If any of you know what these chips are or how to find out your help would be much appreciated.And on to plan B... If any of you would know where to start with the design of the electronics that would convert from the camera's SPI interface to the analog signal that I need. I would imagine that a microcontroller would not suffice but could easily be mistaken. My gut tells me that I need some kind of dedicated video driver chip but I don't have much experience with analog video generation past using some hacky Arduino libraries.So in short if you can look at the link I posted to the existing thermal breakout board and maybe help me out with some tips as to what the chips are on the board are that would be great. Also if you have any tips on a chip to start designing around if I were to whip up my own circuit to drive the video that would also be great.Thanks for your help!Tyler
Thermal Camera Cooled to -196C! Cryogenic HgCdTe (MCT) Detector Teardown - Page 1
Forum section: electronics / projects

author: Hugoneus
author_rank: Frequent Contributor
timestamp: August 23, 2025, 04:35:10 pm
content: You can watch the video here:TSP #256 - Thermal Camera Cooled to -196C! Cryogenic HgCdTe (MCT) Long-Wave Infrared Detector Magichttps://youtu.be/WyHYInjbMIM

author: Manul
author_rank: Super Contributor
timestamp: August 23, 2025, 07:23:41 pm
content: Excellent video, really enjoyed. It is impressive that it achieves such high picture quality and frame rate while using galvanometer scanning. The sensor has to have a really fast response time. Some cameras with 2D arrays exhibit a bit of motion blur when panning and this one is scanning pixel by pixel at high speed and the image stays sharp. And also seems to get decent sensitivity! I once repaired a FLIR HRC-X camera which also used Stirling cryocooling, but it is a much more "boring" camera, cause it uses traditional 2D sensor. Well, perhaps size of main lens (edit: messed up with mm, not sure now) and zoom optics were not boring, otherwise quite straightforward design.

author: Hugoneus
author_rank: Frequent Contributor
timestamp: August 23, 2025, 09:19:42 pm
content: Interesting!

author: mawyatt
author_rank: Super Contributor
timestamp: August 23, 2025, 11:29:40 pm
content: Nice interesting video as usualWay back in 80 at Honeywell we worked on the development of the XM-21 Remote Sensing Chemical Agent Detector based upon "controversial" Passive Spectral Radiometry. Honeywell was also the source for the HgCdTe detectors, and were for most military suppliers. The detectors they created back then were measuring better than theoretical and the USG declared the division in Lexington Mass a national asset and blocked the division sale to a foreign company. Later an "arrangement" allowed the sale to Loral. Never understood why Honeywell wanted and did eventually sell that division!!Here's some links about the XM-21 if interested.https://www.eevblog.com/forum/chat/recalling-an-amazing-electro-optic-instrument-interferometer/https://www.eevblog.com/forum/thermal-imaging/germanium-or-znse-lens-for-diy-hobbiyist-projects/msg3524760/#msg3524760https://www.eevblog.com/forum/chat/more-fun-stories-physicists-and-engineering-nomenclature/Best

author: Hugoneus
author_rank: Frequent Contributor
timestamp: August 24, 2025, 04:03:05 pm
content: Thanks for sharing this.
Thermal camera on Labview  - Page 1
Forum section: electronics / projects

author: DanielPulg
author_rank: Newbie
timestamp: October 29, 2024, 08:18:11 am
content: Hi, I'm trying to get the video the Infiray P2 PRO thermal camera is recording on Labview and get the temperature as well. The problem is that I get the video in greyscale and I think I need it in raw data but I don't know how to get it. I can share a photo with you, if you can help me with this I'll be so grateful
Thermal camera that can see the heat of glossy and matte surface? - Page 1
Forum section: electronics / projects

author: daslolo
author_rank: Regular Contributor
timestamp: April 28, 2019, 01:56:20 am
content: I am using a seek compact pro which has glossy setting, it only multiplies temperature though so I cannot evaluate the heat movement of matte and glossy components in the same picture.Is there a system that can?

author: OM222O
author_rank: Frequent Contributor
timestamp: April 28, 2019, 02:25:16 am
content: I believe some of the FLIR ones allow you to add an "emisivity map" so you can use it across multiple surfaces, but you have to somehow generate that map for your specific object which is really painful.

author: DaJMasta
author_rank: Super Contributor
timestamp: April 28, 2019, 03:50:46 am
content: The usual simple approach is to paint it, matte black spray, even in a less than complete coat, does great. You could also try masking tape or similar, all provided that the temperatures involved aren't too high to allow it.

author: Someone
author_rank: Super Contributor
timestamp: April 29, 2019, 04:58:30 am
content: Just modify the surface:https://www.flir.com.au/discover/rd-science/use-low-cost-materials-to-increase-target-emissivity/

author: daslolo
author_rank: Regular Contributor
timestamp: April 30, 2019, 01:07:48 am
content: Thanks folks,I'd like to apply something temporary on these dedicate PGS ribbons, does anyone knows of a paint that crumples after some time?

author: Heartbreaker
author_rank: Unknown
timestamp: April 30, 2019, 03:09:13 pm
content: Quote from: DaJMasta on April 28, 2019, 03:50:46 amMasking tape or plastic tape are my normal go-to materials because they work resonable well and are cheap.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: April 30, 2019, 05:10:39 pm
content: There are India inks that aren't very waterproof. Maybe airbrush with one of those, then clean in ultrasonic cleaner with a bit of ammonia afterwards. Or maybe make your own- you need a pigment and a lousy binder.I do a lot of IR temp measurement and IMHO paint is the easiest solution.

author: daslolo
author_rank: Regular Contributor
timestamp: May 05, 2019, 05:13:20 am
content: I painted the PGS with china ink, it shows heat much better but also insulates the PGS so heat dissipates less.Apparently you can't see heat without changing the conditions.
Thermal Chamber Control Protocol? - Page 1
Forum section: electronics / projects

author: fourfathom
author_rank: Super Contributor
timestamp: September 16, 2020, 01:37:20 am
content: I want to build a thermal chamber for characterizing oscillators and for general product testing. So far I have modified my toaster-oven reflow controller to give me low-duty-cycle control, and feedback over a USB/serial link, and am using a simple ASCII command set. This gives me a temperature range from ambient up to whatever I set as the high end. It's no good for thermal-shock testing, but slow ramps up and down are good enough for now. (actually, the ramp-up can be pretty fast)Now, I want to modify one of those "reptile incubators" that Dave featured, to give me similar remote control and monitoring with the ability to cool down to perhaps 10 C, and heat to about 50 C.So is there a standard control language I should be looking at as I develop the controller interface? I've glanced at documents from Tenny, Thermotron, etc, and it doesn't appear that they are particularly compatible. I don't plan to include all the features of these pro controllers, but wouldn't mind finding a useful subset, rather than inventing my own non-standard control language.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 16, 2020, 01:56:43 am
content: Just implement SCPI. You don't need super low latency or high bandwidth for a thermal controller.

author: fourfathom
author_rank: Super Contributor
timestamp: September 16, 2020, 05:22:50 am
content: Thanks! I was unaware of SCPI, but see that it is quite wide-ranging, and has a section in the spec for environmental chamber control. Is this commonly used such that if I implemented a minimal set of SCPI my chamber or interface software would likely be compatible with commercial equipment?Here's the document I'm looking at:https://www.ivifoundation.org/docs/scpi-99.pdf
Thermal Coefficients and stability and such.  - Page 1
Forum section: electronics / projects

author: magnus0re
author_rank: Contributor
timestamp: January 04, 2014, 12:08:12 pm
content: Hi. I need some help finding a book or a good source to learn about thermal coefficients, thermal stability and how circuits behave when temperature changes.Why: because I'm designing circuits that I cannot predict how will act without simulations, because I am afraid that thermal effects will skew voltages.this design is analog, with discrete components and opamps, but I would not mind reading books about IC design if they cover the thermal stuff.thanks a lot.

author: Jon86
author_rank: Frequent Contributor
timestamp: January 04, 2014, 12:28:42 pm
content: Just googling and reading up on various specific things is going to be a good start. I don't know if you'll be able to find a book on just this topic, but if you do, please post it here

author: dannyf
author_rank: Super Contributor
timestamp: January 04, 2014, 02:15:22 pm
content: QuoteThose terms can mean vastly different things to different people in different context so it is unwise and unhelpful unless you provide more details.Having said that, it is unlikely it has anything to do with what you are trying to do.

author: SArepairman
author_rank: Frequent Contributor
timestamp: January 04, 2014, 03:35:33 pm
content: dave jones has a video about using a egg incubator (available for 90$ ) in order to get a good idea of how your circuit will behave under various conditions.nothing will substitute building a prototype and putting it in a thermal chamber.the only thing I could think of is maybe hooking it into a linear supply or putting extra filtering on the power supply there as it was probably made by the lowest bidder, but if you put your electronics in a shield box it should not matter (and it probably wont matter anyway I am just a stickler), maybe throwing some ferrite on it might be a good idea though.

author: magnus0re
author_rank: Contributor
timestamp: January 06, 2014, 12:49:49 am
content: Quote from: dannyf on January 04, 2014, 02:15:22 pmYeah. my language skills deterioate exponentially with the time of day. sorry about that. I think I meant "how will act no matter what simulations I do, because I am afraid of thermal drift."Quote from: SArepairman on January 04, 2014, 03:35:33 pmI concur.Thanks a lot for the video link, I had not seen that one before. (and here I am thinking that I've seen every eevblog video).So. I did some searching. "Troubleshooting analog circuits" and "Analog circuits - World class designs" had some stuff about tempco scattered around in it, but nothing that really informs you about the topic. Maybe this is nor really that big of a problem. oh well. Thanks.
Thermal Compounds - Page 1
Forum section: electronics / projects

author: Pat Pending
author_rank: Regular Contributor
timestamp: September 19, 2012, 08:18:30 pm
content: The HP DV6 laptops are well known for loud fan noise, but lately my DV6 went into thermal shutdown.Once the heat pipe was removed, it revealed grey heat sink compound caked solid around the processor.I cleaned off the old solidified compound and applied some white no name Si grease - good enough for now.So my questions are,Will it (white Si) also dry out and how long till that happens.And if the average metal loaded pastes perform say 5 times better (W/mK), well what does that mean, when the thickness of the layer is 3mil thick?I tried reading the lit but some like imperial units and others metric while some quote the inverse ratio - marketing spin Tssh!How would the temperature increase across the junction compare for a 40W processor.I figured metal loaded pastes might show a 0.15 degrees junction increase whereas the white Si variety might be one whole degree. Yes/No?

author: Rerouter
author_rank: Super Contributor
timestamp: September 19, 2012, 08:25:35 pm
content: 1, it will though being a no name paste it is hard to say in how long, even the jaycar stuff i use is only now starting to degrade 8 years in,2. 5 times better generally means nearly nothing in this application as its rarely the paste that is limiting the dissipation in a laptop3. the layer should be as thin as possible! 0.3mm to a few microns, its purpose is only to fill in the irrgularities of the surfaces,

author: M. András
author_rank: Super Contributor
timestamp: September 21, 2012, 01:13:53 pm
content: tighten the screw with feel, the excess will come out from the side if the stuffs is conductive large amount of excess can be a problem. this method works for me on computers for 10 years now

author: ptricks
author_rank: Frequent Contributor
timestamp: September 21, 2012, 02:17:53 pm
content: It doesn't matter if the paste appears dried up as the liquid nature of the compound when it is fresh isn't what does the heat transfer. The liquid they put into paste is used to make the ingredients in the paste easier to apply. What matters most is an even thin coat. I have seen equipment 30+ years old working fine with plain silicon paste, the paste is so hard it seems like cement.You can use anything you like to replace the old compound. Some recommend the arctic silver stuff, but it isn't the easiest thing to apply. I still use the old white heatsink compound, it works and it is cheap.

author: SeanB
author_rank: Super Contributor
timestamp: September 21, 2012, 03:17:19 pm
content: I used to make my own, using Zinc oxide powder and Dow Silicone grease, blending them together with acetone to improve mixability then stirring for a half hour before leaving it in a warm spot outdoors to flash off the solvent. Worked well for all applications, most of the time was to fix heat spreaders onto the chassis to get the heat out and into the big casting. Did many a 2N3773 with this as well.
Thermal Cooling SOT-223 - Page 1
Forum section: electronics / projects

author: sacherjj
author_rank: Frequent Contributor
timestamp: February 10, 2012, 06:46:36 pm
content: I'm looking at making a slightly simpler version of Dave's PSU in the future. I'm thinking about going all/mostly SMD, to keep size down, so it is easier to have two isolated to make +/- supply in a fairly small box.This got me thinking about TO-220 vs SOT-223 packages. TO-220 cooling is easy. I've got tons of heatsinks lying around. Are there SOT-223 heatsinks? I understand that a common method is just pure copper board surface, but that really wouldn't do for an SOT-223 LT3080 in a heavily loaded PST. I'm not really seeing anything on Digikey, but I may be searching wrong.This is still currently academic, as I will most likely go with TO-220. But may try SOT-223 for the learning experience, if possible.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: February 10, 2012, 08:07:57 pm
content: There's not much you can do with SOT223. The only usable thermal path is via the pins, particulary the thick pin on one side. So the amount of heat that can be extracted is limited to the thermal conductivy of the copper pad, which isn't that great. Coincidentaly, I was looking into such data this afternoon, and saw that the improvement in cooling practically stops after less than 10mm. Small SMD heatsinks (http://ca.digikey.com/1/5/aavid-thermalloy-va) exist which can be soldered over the device, but actual improvement is not that great, again due to the thermal resistance of the thin copper layer of the PCB.

author: amspire
author_rank: Super Contributor
timestamp: February 10, 2012, 11:34:11 pm
content: Even with perfect heatsinking, the SOT223 just cannot handle much power. With perfect heatsinking , you are looking at about 4 watts at best, so that means a 10V 300mA power supply.With real-world heatsinks, you would probably do extremely well to make a 10V 150mA supply.

author: sacherjj
author_rank: Frequent Contributor
timestamp: February 11, 2012, 01:53:16 am
content: Thanks for the info both of you. Looks like I wasn't missing something special from my analysis. TO-220 it is!
Thermal Cycler - Graphite Sheet With Pattern - What is it? - Page 1
Forum section: electronics / projects

author: crmarcos88
author_rank: Newbie
timestamp: August 18, 2023, 06:46:46 pm
content: Hello all!I want to know what function is performing the graphite sheet pattern I have in a Thermal Cycler that works with some Peltier Cells.Thanks in advance for any bibliographical sugestions.Regards,Marcos.

author: Uunoctium
author_rank: Frequent Contributor
timestamp: August 18, 2023, 07:25:28 pm
content: thermal conductivity!https://www.cfccarbon.com/news/thermal-properties-of-graphite-thermal-conductivity.html

author: thm_w
author_rank: Super Contributor
timestamp: August 18, 2023, 10:06:04 pm
content: The pattern looks to be to form a serpentine connection to get a reasonable amount of resistance, so it can act as a heater coil.
Thermal EMF of lead free solders? - Page 1
Forum section: electronics / projects

author: splin
author_rank: Frequent Contributor
timestamp: August 13, 2015, 09:54:38 am
content: Does anyone have any figures for the most common lead free solders against copper and kovar? I did spend some time looking around but couldn't find any numbers.

author: helius
author_rank: Super Contributor
timestamp: August 13, 2015, 11:16:12 am
content: "Unfortunately, the thermal EMF coefficient of Kovar against copper is one of the highest among the alloys used in electronics (-35µV/°C).""the thermal EMF value for copper vs. platinum (7.6µV/°C)"(http://www.vishaypg.com/docs/49871/theremf.pdf)The Seebeck coefficient is determined by the composition of a single material. There is no thermoelectric effect caused by "different materials against one another". Nevertheless, the figures are quoted relative to a common alloy because that is the way they are measured. By subtracting the contribution from the common alloy (which is determined using a chemical method) you can find the Absolute Thermoelectric Power of the alloy under test.The ATP of copper is +1.94 µV/K, which makes the ATP of Fernico I -33 µV/K, and the ATP of platinum -5.7µV/K.I've seen papers that place the ATP of SAC407 at -1.2 µV/K, but that isn't a common lead free solder. In any case it seems to be lower in magnitude than the ATP of Sn63Pb37 at -4.8 µV/K.One reason that the Seebeck coefficients of solders are rarely printed may be that they are irrelevant to properly designed circuits.
Thermal gum style gab fill type identification ? - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: November 02, 2023, 09:15:52 pm
content: in this video at 18:33https://youtu.be/6ULZ13Yivhosee this orange-pink type, I also got a unit with light gray type,same sticky gum type of paste,it is crasy how heawy it is, and it is very impressive how well it conduct heat.they use it to fill 2-4 mm gabs with, and tey simply apply it using a 3D machine dispenser,the board and its parts, will press it into perfect shape, and it stay like this, it also stay nice and fresh,hard and sticky, but not dry and brittle, i did score as much as i could for my own design prototypes,BUTI like to order more, but I can't find this type anywhere,any one of you got an idea ? where to get it, what can it be called ?I can only find the transistor / cpu type of heattransfer compound, it is far from this matarial

author: temperance
author_rank: Super Contributor
timestamp: November 04, 2023, 12:02:43 am
content: I think a very good one is this:https://www.tglobaltechnology.com/products/Up to 7 W/mk for the putty type stuff and and 10 W/mk for thermal PAD's. (Used those not so long ago. They do what they advertise and custom PAD shapes are no problem.)But if anyone knows of something similar with similar specifications (not conductive) I'm interested in hearing about those.
Thermal heat dissipation through PCB copper plane (Shape variants) - Page 1
Forum section: electronics / projects

author: anishkgt
author_rank: Frequent Contributor
timestamp: January 03, 2021, 11:46:58 pm
content: Hello All,In the midst of designing a Buck Converter i am looking at ways to dissipate heat from a buck converter using the PCB copper. Would be interested to know how everyone does it. Interestingly variants of shapes used. TI (https://youtu.be/Y-hzwMEBd6A) suggests using hexagonal for better dissipation. Was wondering if round shapes would dissipate more than hexagon, pentagon or square. Maybe @eevblog dave could do a video on it and see which shape dissipates more heat.Regards,George

author: S. Petrukhin
author_rank: Super Contributor
timestamp: January 04, 2021, 12:08:25 am
content: The guys at TI are nice, but sometimes they scare me like shamans...
Thermal Heatsink Tape - Page 1
Forum section: electronics / projects

author: BleedBlue
author_rank: Newbie
timestamp: April 02, 2021, 06:23:07 pm
content: I have a controller with multiple driver boards for stepper motors. They are mounted on an aluminum heatsink. They are using Kaptone tape as an insulator from the heatsink. Is there a better way to do this, than to use Kaptone tape? If you replace a driver board you have to be very careful not to damage the tape, I just think that there could be a better solution than using Kaptone tape.

author: Siwastaja
author_rank: Super Contributor
timestamp: April 02, 2021, 06:40:13 pm
content: Yes, there are better ways. Thin Kapton tape is indeed easily damaged by any metal dust, burrs, or substandard mounting of components at angle. Thick Kapton tape is safer, but the thermal conductivity is significantly worse compared to proper Thermal Interface Materials, so when used thick, it doesn't typically conduct heat enough to be usable as thermal interface material.The typical solution is a so-called Silpad, typically 0.5mm to 2mm thick, may be glass fiber reinforced. It "squeezes out" a tiny bit when compressed giving good contact. Thermal conductivity still kinda sucks, but this is the typically workable tradeoff between the ease of installation, acceptable thermal conductivity, and safety against damage when insulation matters.

author: coppercone2
author_rank: Super Contributor
timestamp: April 02, 2021, 07:34:33 pm
content: just keep in mind that silpads age

author: wizard69
author_rank: Super Contributor
timestamp: April 02, 2021, 08:32:32 pm
content: Well if this is a design you have control over, it might be best to ground the driver electronics to the heat sink (if that is electrically possible). The idea being that no insulation is a better choice. This is workable for small heat sinks that can be electrically isolated. On some designs the heat sinks literally clip on.There is no right answer here, working on industrial electronics I've seen designers take almost every approach that can be imagined. This includes some sort of glue or cement compound bonding everything to a heat sink. I'm not sure what the compound was but it made the controller throw away only.In the end it depends upon what you are trying to isolate. IF you look down the road to when the item will be repaired, it is a different story again and you should choose an easily sourced and repaired isolation method.

author: coppercone2
author_rank: Super Contributor
timestamp: April 02, 2021, 09:08:14 pm
content: I personally hate live heat sinks, as I hate live non insulated stuff on the edge of a chassis, those are the 2 things that can get you real easy.A live heat sink if its HV turns into a gigantic hazard, and uninsulated stuff near a chassis edge makes it easy to shock yourself when you lean over.But if it is HV, and you do isolate it, you should scribe into the heat sink that it can be possibly live, because it does create a false sense of security.
Thermal imaging camera Microbolometer design detail - Page 1
Forum section: electronics / projects

author: Fraser
author_rank: Super Contributor
timestamp: October 18, 2013, 01:52:05 pm
content: I have found an interesting document that was written by a student with input from knowledgeable sources, including Inframetrics (now part of FLIR)It may be of interest to others who wish to understand modern TICs internal workings.The document contains some interesting detail and pictures, including the physical aspects of the microbolometer on page 40.I was interested in the peltier temperature stabilisation implimentation and this is clearly detailed here. It would appear that one of my faulty TICs has a fault in the peltier control loop but at at least it is unlikely to be a physical defect inside the detector capsule.http://archives.njit.edu/vol01/etd/1990s/1997/njit-etd1997-027/njit-etd1997-027.pdfI also attach an Indigo data sheet from 2006 detailing a TIC that does not use a Thermoelectric temperature stabiliser.To fellow 'Thermal Geeks' ENJOYFraser

author: Fraser
author_rank: Super Contributor
timestamp: October 18, 2013, 05:17:43 pm
content: Interesting patent from Honeywell.http://www.google.co.uk/patents/US5420419

author: madshaman
author_rank: Frequent Contributor
timestamp: November 04, 2013, 12:41:47 pm
content: Sweet! I wasn't looking for TIC info but *was* looking for sources on Peltier temperature stabilisation; much obliged!

author: Fraser
author_rank: Super Contributor
timestamp: November 04, 2013, 12:47:09 pm
content: You are most welcome

author: pomonabill221
author_rank: Frequent Contributor
timestamp: December 30, 2013, 10:48:49 pm
content: just looked at this thread.... VERY interesting! Thanks for the links!
Thermal insulation material - Page 1
Forum section: electronics / projects

author: ceoxrad
author_rank: Regular Contributor
timestamp: June 01, 2020, 11:39:55 am
content: Hello everyone. This question is somewhat related to a problem I'm facing with my laptop (link to that thread down below), but since this is more related to electronics and may be of use to other people I open a thread here.Does anyone know a thermal insulation material available in thin sheets (<=1mm) that can be used to shield an hot PCB (50-60 *C) from a plastic enclosure?I'd like to insert a layer of the stuff between the metal rollcage of a laptop and the outside plastic bezel. I've looked into rubber insulation tape used in HVAC but it's far too thick.Any help is appreciated, Thank you allOriginal thread in computing:https://www.eevblog.com/forum/general-computing/thinkpad-w540-and-ubuntu/

author: Gyro
author_rank: Super Contributor
timestamp: June 01, 2020, 11:57:27 am
content: This doesn't sound advisable. The only reason that the PCB is maintaining 50-60'C is that it is losing heat through the case. If you start adding thermal insulation, then the temperature of the PCB is going to run hotter, possibly to the point of failure.EDIT: Sorry, for some reason I read this as laptop adapter.

author: ceoxrad
author_rank: Regular Contributor
timestamp: June 01, 2020, 12:10:16 pm
content: Thank you for the input.I understand the problem, but I don't want to insulate the whole area, just a tiny spot under the palmrest.The PCB is located inside a metal rollcage that heats up when the device is in use.I attached a picture with the area I intend to insulate, directly below the palmrest. Mainly is that thin flap of metal over the expresscard slot.I should have explained better in the first post (sorry!). The pcb is not directly underneath the palmrest.Do you think that is feasible in this case?

author: Marco
author_rank: Super Contributor
timestamp: June 01, 2020, 01:00:40 pm
content: With that little space you won't do better than an airgap and limiting radiation (well, except for vacuum and limiting radiation).Spray both surfaces with reflective paint and use standoffs to maintain an airgap for most of the area.