hybridfree/eevblog-posts huggingface dataset:
Texas Instruments TO-5 part Identification - Page 1
Forum section: electronics / projects

author: slim
author_rank: Contributor
timestamp: May 22, 2017, 06:36:26 pm
content: Hello All,I am trying to identify a older TI part I have in my stock.Please excuse the poor photo.ThanksSlim

author: Zero999
author_rank: Super Contributor
timestamp: May 22, 2017, 10:36:32 pm
content: My gut instinct tells me it's a JFET.Have you performed any tests with a multimeter?

author: DaJMasta
author_rank: Super Contributor
timestamp: May 22, 2017, 10:43:05 pm
content: +1 to jfet, the J and a three digit number is still a common way for them to be marked. I've seen a few marked with a U and a number, but U391 seems to be a no-go as well.

author: Zero999
author_rank: Super Contributor
timestamp: May 23, 2017, 08:02:59 am
content: The middle pin is usually the gate and the outer pins drain/source. J-FETs are normally symmetrical: the are drain/source pins reversible. A multimeter can be used to check that it's a J-FET and whether it's P or N-channel.Use the diode check on the multimeter to test for a 0.6V drop between the middle pin and either of the outer pins. If it's N-channel, the inner pin will show up as an anode and the outer pins cathode and there will be no current flow when an outer pin is made positive, with respect to the middle. A P-channel J-FET will be the reverse of the aforementioned: middle pin cathode and outer pins anode.Connect the gate (middle pin) to one of the outer pins. The resistance between the outer pins should be under 1k. The resistance may be higher in one direction than the other, which will be because the bias on the gate will change. If the gate is connected to the other pin, the resistance will swap round.If the above doesn't work, then it could have a different/non-standard pin out, in which case test it again assuming one of the outer pins is the gate. Failing that it's faulty or isn't a J-FET.
Text render engine - Page 1
Forum section: electronics / projects

author: blueskull
author_rank: Unknown
timestamp: April 13, 2015, 01:43:24 am
content: Hi.I recently got an Intel Edison board, and I want to some interesting things on it. What I want to do is to make a music player on it which supports international languages (file name font).Since Edison doesn't come with any display function, there is no way to use traditional Gtk/Pango solution. To add graphics, I need to add a SPI LCD.The problem is how to render file names and display it on the LCD. I only need to render simple scripts, specifically Latin and CJK. Complex scripts such as Arabic and Hindi is not on my list now.Theoretically I can do this with Freetype, and it can support Latin and CJK. What I don't know is how to detect language, and use proper font?Is there a "global language" font out there now?

author: Lukas
author_rank: Frequent Contributor
timestamp: April 13, 2015, 07:51:35 am
content: So you only need to display text? Why not use Cairo/Pango and let it render to memory? (Image surface) Then send that to the LCD.

author: rs20
author_rank: Super Contributor
timestamp: April 13, 2015, 08:02:50 am
content: Quote from: blueskull on April 13, 2015, 01:43:24 amThat's almost any half-decent font, as long as you use Unicode.

author: Stupid Beard
author_rank: Regular Contributor
timestamp: April 13, 2015, 08:14:22 am
content: Quote from: blueskull on April 13, 2015, 01:43:24 amAs long as you use Unicode, this is easy.http://dejavu-fonts.org/wiki/Main_Pageis one set of fonts with a liberal license that should cover most of it.You don't need to have every font covering every Unicode codepoint. Any halfway decent modern text renderer will fallback to alternative fonts if the codepoint it is trying to render does not exist in the font it's trying to use. The asian, arabic, etc glyphs should be easy to support this way provided you have some way of rendering the text right to left.

author: dom0
author_rank: Super Contributor
timestamp: April 13, 2015, 09:01:11 am
content: Quote from: Lukas on April 13, 2015, 07:51:35 amAbsolutely. Qt has some support for this built-in, catchword qvfb in the Qt docs.Oh, and, there are a bunch of framebuffer drivers floating around. So you can actually have "real" displays (kernel-provided framebuffers) for your SPI displays.

author: LaserSteve
author_rank: Super Contributor
timestamp: April 13, 2015, 05:54:18 pm
content: There are also " Hershey Vector" fonts in the freeware domain, Courtesy of the U.S. Government.Steve
TFP401 power decoupling + gnd plane woes - Page 1
Forum section: electronics / projects

author: Zinglish
author_rank: Newbie
timestamp: February 04, 2017, 03:41:45 pm
content: I am currently designing an HDMI to 24bit TFT board with the TFP401 decoding the DVI signal and have some woes with power and planes.So my first issue with power is decoupling caps. ThePower Supply Recommendationsdon't match up with thePower Supply Layout. Which one should I go with?Second issue I have is how do I go about separating the different power and ground planes? Could someone post a good and bad example of separation between different signal ground and power planes? For example I know that analogue and digital planes should be 'separate' but at what point do I join them and how do I route them without affecting the speed of the signal lines? Is this a good resource:https://www.maximintegrated.com/en/app-notes/index.mvp/id/5450?

author: Siwastaja
author_rank: Super Contributor
timestamp: February 04, 2017, 04:18:25 pm
content: Quote from: Zinglish on February 04, 2017, 03:41:45 pmAlmost never. Even less so with digital-only design.If you need to ask, you want to use one ground plane only.Search the forum, you'll find a lot of discussions and a lot of good reference material on this.
TFT LCD interface type - Page 1
Forum section: electronics / projects

author: hendrix
author_rank: Contributor
timestamp: March 26, 2013, 10:34:32 pm
content: Hi ppl,I like to figure out the TFT interface protocol that I am giving below from a site that I found (http://www.electricstuff.co.uk/ipodlcd.html) I tried contacting the site admin but, no luck. I need to learn the protocol to substitute the LCD for another smaller size. Here is the pin outs, as figured by the original author:Pin Function1 Not Used2 3.1V Supply3 1.8V Presumably I/O supply. All I/Os run at 1.8v levels4 0V5 /Reset.6 /CS Chip select7 /WR write strobe8 RS Selects command/data register ( called CD in some datasheets)9 /RD read strobeData bus Colour10 D0 Blue 011 D1 Blue 112 D2 Blue 213 D3 Blue 314 D4 Blue 415 D5 Green 016 D6 Green 117 D7 Green 218 0V19 D8 Green 320 D9 Green 421 D10 Green 522 D11 Red 023 D12 Red 124 D13 Red 225 D14 Red 326 D15 Red 427 0V28 Vsync out. Goes high for 84.5us at frame rate of 47Hz29 0V30 Backlight -31 Backlight + Vf is 13.7V ( 4 white LEDs in series)32 Not usedCan anyone help?Thanks.

author: marshallh
author_rank: Unknown
timestamp: March 26, 2013, 10:43:26 pm
content: There's nothing really unique about this particular screen, it's a typical single-ended (as opposed to LVDS used in larger screens with higher pixel clocks) LVCMOS interface with parallel RGB.You can open up Digikey and check out datasheets for a similar screen. Optrex has one.

author: mariush
author_rank: Super Contributor
timestamp: March 26, 2013, 10:48:36 pm
content: Do what that guy did.Search for color LCDs and check the ones which have similar connectors:http://www.digikey.com/product-search/en/optoelectronics/display-modules-lcd-oled-graphic/524918For example, here's this one:http://www.digikey.com/product-detail/en/NHD-2.4-240320SF-CTXI%23-1/NHD-2.4-240320SF-CTXI%23-1-ND/2626410The datasheet shows the pinout somewhat similar to your pinout:http://www.newhavendisplay.com/specs/NHD-2.4-240320SF-CTXI-1.pdfAnd the same datasheet says :Driver InformationBuilt?in ILI9340 controller.See specification athttp://www.newhavendisplay.com/app_notes/ILI9340.pdfGo to that link and see how that driver works. Your screen may have the same functions as that ILI9340 ...
TFT LCD voltages and sequencing - Page 1
Forum section: electronics / projects

author: dansky
author_rank: Newbie
timestamp: April 07, 2023, 11:12:06 am
content: Hello guys, that's my first post here so nice to meet you all. In the recent project I am working on I want to connect a TFT LCD to ESP32-S3. I would be using the LCD hardware interface of ESP32, so I only need to take proper care of display power management. The model I have currently, is ZJ050NA-08C by Innolux.I have already figured out the way of generating all the needed voltages (DVDD, AVDD, VGH, VGL, VCOM) using boost converters and charge pumps (quite a common topology). But I have some doubts regarding the needed power-up and power-down sequence.So first, the official datasheet mentions the following sentence:QuoteThis gives me a hint already, about the correct sequence of events at start-up. There is also a timing diagram provided though (attached).Here we can see that after applying VDD (and I am assuming it's DVDD here, right?) I should apply AVDD asap, and introduce some small delay for VGL and VGH lines. This should be easy enough with some transistors and RC-based delay circuits on the VGL and VGH lines. What really is a mystery for me is a shut-down sequence (also attached).Can you guys please help me understand that sequence? I have a few questions:1. I can see that I should keep the VGH and VGL lines for at least 20ms after the backlight turns off. This should be quite easy with some RC circuits again, as both VGL and VGH are said to consume only as little as 0.2mA of current. But do you happen to know where might that requirement come from?2. The sequence shows the AVDD and VCOM lines to go down after the VGH/VGL but without giving any specific timings. Does that mean I can turn these off whenever I want, as long as it's after VGH and VGL? This might be a bit tricky as AVDD line is said to consume around 10mA or current, so keeping it active might be a bit harder. Do you have any ideas how I can achieve this?3. We can see that I should release the data lines and shut down DVDD line at least 50+ms after VGH/VGL. That seems doable as long as I still have power supplied for the whole board. What if it's not a soft shut-down, triggered by the ESP but it's a result of cutting off the power for the whole board? For example if I unplug the power supply cable. I can maintain some power for the VGH and VGL lines, but doing this for AVDD and DVDD lines, which both can consume lots of current is not really doable for 50+ms (unless I have some battery). So how should I handle this case? Should I just ignore the 'full power loss' scenario, as it's generally a problem for the LCDs and I can't do anything about this?Thanks in advance
TFT/LED displays: min DCLK freq - Page 1
Forum section: electronics / projects

author: whyami
author_rank: Newbie
timestamp: July 01, 2021, 12:09:21 pm
content: I'm sure I'm not the first person to consider leaving out the RA8875 or similar and driving a AT070TN94 7" TFT 800 x 480 or similar direct from a uC such as ESP32 using latches yet I can't find any examples of anybody even trying this. Looking at the spec sheet it all looks doable with one serious caveat: DCLK frequency. The AT070TN94 spec sheet lists the minimum DCLK frequency as 26.4 MHz but this speed wouldn't be possible to achieve with bitbanging on a simple uC.Is the high clock frequency really a recommendation so display updates will happen quickly or is that minimum frequency really required to make the display show any images at all? My application is to show only one image continually so as long as the image doesn't flicker or dim I don't need a high display update rate. I don't know if, like CRTs, there is a display refresh rate and the image will dim/flicker unless constantly updated, in which case a min DCLK freq in the 10s of MHz then makes sense.https://cdn-shop.adafruit.com/datasheets/AT070TN94.pdf
TG315 Signal generator amplitude doesn't go to zero - Page 1
Forum section: electronics / projects

author: MatteoGaria
author_rank: Newbie
timestamp: February 04, 2023, 10:20:37 pm
content: Hi all,I'm in the process of repairing and calibrating a TTi TG315 function generator and I noticed that the amplitude control doesn't allow to go to full 0V output. This is by design, because the amplitude potentiometer is wired like a volume control but the leg that goes to ground has in series a 75 ohm resistor.The minimum output is 1V rms (sine) unless attenuator switches are used.I was just wondering if other signal generators are like this one, and if there's a precise reason to do this. User manual doesn't say nothing about.Thanks in advance

author: moffy
author_rank: Super Contributor
timestamp: February 04, 2023, 10:46:19 pm
content: All of the general purpose test signal generators I have used will go down to 0V output.
ThaiKit Curve Tracer Physical Placements - Page 1
Forum section: electronics / projects

author: watchmaker
author_rank: Unknown
timestamp: February 12, 2024, 01:34:36 pm
content: For giggles I bought the kit and a Jameco two output PSU since it comes with the xformer. Had to laugh at myself,by the time we are done with the box, PSU, connectors and switches, the bargain kit results in almost 3 times the money.I remember from my tube days that we had to be very careful about wire routing and shielding. So the xformer is at the opposite corner of the box.I installed the PSU and I have plenty of room for the CT board. Given some of the noise complaints, would a copper shield be useful?I never really understood ground loops other than they were undersirable. If I tie the output grounds and the PSU ground to the one point in the case along with the earth, is that appropriate? Jameco designed the PSU to float but I used a 3 prong power connector and plan to tie the case and output grounds to that.THANKS!!

author: Vovk_Z
author_rank: Super Contributor
timestamp: February 12, 2024, 02:37:04 pm
content: Quote from: watchmaker on February 12, 2024, 01:34:36 pmYes, that's a usual thing. That's why I tend to bye ready-made tools if they exist despite I am a DIYer.

author: bostonman
author_rank: Super Contributor
timestamp: February 12, 2024, 02:45:49 pm
content: QuoteIs it worth the money or do you feel a better unit exists for the same amount?

author: watchmaker
author_rank: Unknown
timestamp: February 12, 2024, 04:50:24 pm
content: Quote from: bostonman on February 12, 2024, 02:45:49 pmThe Jameco PSU cost $35. The metal box was another $20. The line cord input (fused and lighted) was $8 for 2. Add banana jacks, two on/off switches (W/ color coded toggle covers), bnc bulkheads and you are close to $100 for everything.Is it worth it? I have a BK curve tracer which is too big for the bench. This is 1/2 the size of a DMM. I like that it uses op amps which I am just learning about. All the components are stock items. I figure there are $10 worth of DigiKey parts? It is the board that matters.I just finished doing my placements I am putting the CT board vertical on the side farthest from the PSU. Scope outputs will be in the upper back right corner where the leads will be out of the way. Switches and ECB jacks will be on the front right. All of these make for 2 inch runs at most. Could go 1/2 inch. I will use disconnects for the front panel stuff; I gotta figure out a nice disconnect for the scope outputs.The box I am using is nice. The front and back panels can be removed and the top comes off exposing the other two sides.I have used plastic parts boxes for some things, but I figure this might as well be "nice" rather than utilitarian. Hint: paint the INSIDE of the parts boxes.Also a front panel power on LED in the upper left.Gotta figure out nice labeling, but it is fun. I likely will install a shield between the PSU and CT since I have so much room.
THAT 1583 LTSpice Model - Page 1
Forum section: electronics / projects

author: electrovanga
author_rank: Contributor
timestamp: June 23, 2024, 08:47:06 pm
content: Hi,I would like to do a LTSpice simulation using the THAT 1583 IC. However, I couldn't find its model on the internet. Could someone please help me find it?

author: magic
author_rank: Super Contributor
timestamp: June 23, 2024, 08:59:37 pm
content: Google says:https://thatcorp.com/device-models/

author: electrovanga
author_rank: Contributor
timestamp: June 23, 2024, 09:56:17 pm
content: Hi,Many thanks. Google really doesn't show this to me.

author: SiliconWizard
author_rank: Super Contributor
timestamp: June 23, 2024, 11:15:29 pm
content: Quote from: electrovanga on June 23, 2024, 09:56:17 pmJust tried - "interestingly", with the search phrase "THAT 1583 LTSpice Model" or even "THAT 1583 Spice Model", Google doesn't show this page either, at least not in the first page of results.But if you look for "THAT Spice Model", the link appears as the first result. Yeah, search engines are not that smart. (Note that "AI" is not that smart either, as the results can vary widely depending on how you ask, hipsters call that "prompt engineering" these days. Yeah. But I digress slightly.)Note that search results for you, magic or I on Google may not be exactly the same for identical keywords. So.

author: magic
author_rank: Super Contributor
timestamp: June 24, 2024, 05:08:36 am
content: I think I used "site:thatcorp.com spice" after getting no useful results from the obvious queries, because I was starting to wonder if THAT releases any models at all.

author: ArdWar
author_rank: Frequent Contributor
timestamp: June 24, 2024, 05:24:55 am
content: Quote from: SiliconWizard on June 23, 2024, 11:15:29 pmGoogle do optimize out your search result based on your previous searches, browsing habit, location, etc. So yes, different people searching the exact same keyword will almost guaranteed to get different results.It doesn't help that "THAT" keyword is so generic and the brand is not that popular (heh) it often ignored or completely misunderstood by search engines.

author: electrovanga
author_rank: Contributor
timestamp: June 24, 2024, 09:05:12 am
content: Many thanks all the people commented on this post here. I got very good tips.
THD Measurement - Page 1
Forum section: electronics / projects

author: cncjerry
author_rank: Unknown
timestamp: December 28, 2015, 01:20:54 am
content: What is the generally accepted way to calculate THD?I've seen it using the fundamental only as the denominator and also the summation of the fundamental plus the harmonics as the denominator.I'm currently using THD = (sqrt((P2+P3+P4+P5+P6+P7+P8+P9)/P1) x 100) Where the number equals the harmonic with 1 being the fundamental. Another way to state it is the square root of the summation of the powers of the harmonics divided by the power of the fundamental. I have a program the measures the fundamental and up to 9th harmonic on a spectrum analyzer in dBm then I convert it to power in watts. I've been comparing some signal generators I have for spectral purity and alignment if needed.The alternate way I've seen it is the square root of the summation of the harmonics divided by the summation of the harmonics and fundamental. This calculation would result in a much lower number. In all cases the resulting fraction is multiplied by 100 to get percent.Thanks

author: dom0
author_rank: Super Contributor
timestamp: December 28, 2015, 01:29:37 am
content: Almost everyone uses the first definition. Although it doesn't really matter below maybe -40 dB THD.

author: DanielS
author_rank: Frequent Contributor
timestamp: December 28, 2015, 04:55:03 pm
content: I agree with the first definition too.If you want THD+N instead, since THD+N is everything that isn't the fundamental, you can calculate it by subtracting P1's RMS value from P's RMS value: THD+N = sqrt(PRMS^2-P1RMS^2)/P1RMS
THD vs frequency - Page 1
Forum section: electronics / projects

author: Lucky-Luka
author_rank: Unknown
timestamp: December 28, 2019, 08:21:40 pm
content: Hi allI've found this link:http://www.audio-perfection.com/audio/audio-total-harmonic-distortion-analyzer-for-ltspice-making-thd-vs-amplitude-and-frequency-sweeps-in-ltspice.htmlI'm trying to understand how to use this script properly.Can someone tell me how I can plot the THD vs freq graph?After I've simulated the given example , I went to the error log (CTRL-L) and than I right clicked the log window.THD vs output amplide graph appear after I select "plot selected meas data"I have even changed the analyzer_controls.txt commenting the amplitude sweep and uncommenting the freq sweep but the result doesn't change: I cannot display the THD vs freq graph I'm looking for.If there is another method to achieve a thd vs freq graph using LTSpice it's ok for me.Cheers

author: Calvin
author_rank: Regular Contributor
timestamp: December 29, 2019, 05:03:41 pm
content: Hi,here´s one I found quite simple and useful.Open the .txt File with a editor and configure the analyzer parameters after your fashion (basically its just commenting/uncommenting lines and setting a fixed parameter)You can choose either THD over Frequency at a fixed Amplitude, or THD over Amplitude at a fixed Frequency.The analyzer runs multiple transient runs, which means that calculation time becomes long and raw-File size can become very large.Plotting results: View --> Spice error Log and then Plot .step'ed .meas dataregardsCalvin

author: Lucky-Luka
author_rank: Unknown
timestamp: December 29, 2019, 10:04:42 pm
content: HiI attach 2 pics.The first one shows the configuration text file.Is it ok to comment it like that to obtain THD vs freq?The second pic is the error log after the simulation has finished.An error and several warnings...What do you think about it?Cheers
THD+N measurement from WAV file with GNU Octave - Page 1
Forum section: electronics / projects

author: truzz
author_rank: Newbie
timestamp: July 02, 2016, 11:16:35 am
content: Hi folks,I have a pre-recorded mono .WAV file of a 1k sine, recorded from my DUT.Is there a function similar tothdto use in GNU Octave?Googling, I've found this matlabtutorialabout measuring THD.Is it possible to implement a similar code into Octave?Has anyone written a'simple solution'code for this task?Thanks.

author: MK
author_rank: Regular Contributor
timestamp: July 02, 2016, 07:54:32 pm
content: By design Octave has a similar command set to Matlab, but as it is free it avoids being a total copy, so run the code in octave and tweak till it runs.

author: truzz
author_rank: Newbie
timestamp: July 03, 2016, 10:26:32 am
content: Thanks!When I try to run into Octave I get the following:warning: the 'thd' function belongs to the signal package from Octave Forge buthas not yet been implemented.Please read <http://www.octave.org/missing.html> to learn how you cancontribute missing functionality.warning: called from__unimplemented__ at line 524 column 5error: 'thd' undefined near line 1 column 28It seems that I can use the code in the exemple only in Matlab.Has anyone done this implementation in GNU Octave? I hope to find a solution.TIA.
The ADAU1467 audio DSP in my Active+ amplifier project - Page 1
Forum section: electronics / projects

author: FXtreme-Electronics
author_rank: Newbie
timestamp: September 24, 2025, 12:06:23 pm
content: I’ve been working on a high-end audio amplifier system as part of my Active+ project and thought I’d share a section of the PCB hereThe heart of the design is the ADAU1467 audio DSP from Analog Devices. I went with this chip because it strikes a nice balance between power and integration.It’s advanced enough for serious audio processing, yet still efficient enough for portable battery-powered systems like this. It has become my go-to DSP for compact high-performance audio systems.Pictures below show the Mainboard and DSP section.Has anyone here used the ADAU1467 (or its smaller siblings) in audio projects before? I’d be interested to hear your experiences!Any feedback is also welcome of course
The ARRL Handbook 2015 - Page 1
Forum section: electronics / projects

author: joeqsmith
author_rank: Super Contributor
timestamp: April 02, 2015, 01:26:01 am
content: I picked up a copy of the latest ARRL Handbook.http://www.amazon.com/ARRL-Handbook-Radio-Communictions-Communications/dp/1625950195/ref=sr_1_1?ie=UTF8&qid=1427937156&sr=8-1&keywords=arrl+handbook+2015I have had a few versions of this book over the years. My last copy was from 1985 and my oldest copy is from 1954. While a lot of the basics never go out of style, it's interesting to see how the book has changed to reflect changes in technology. It seems they focus less on home projects now and more on the theory. Still a good reference book.
The Art of Electronics 3rd Ed. Full of proofreading symbols?! - Page 1
Forum section: electronics / projects

author: 74HC04
author_rank: Contributor
timestamp: April 13, 2015, 01:03:15 pm
content: My shiny new copy of TAoE 3rd edition arrived today. However it is *full* of proofreading symbols in many of the chapters (e.g. ¶ and §). Does anyone else have a copy like this?

author: dom0
author_rank: Super Contributor
timestamp: April 13, 2015, 01:18:49 pm
content: Like in the review part of all chapters? Maybe it's meant as a somewhat ... odd enumeration symbol?

author: 74HC04
author_rank: Contributor
timestamp: April 13, 2015, 01:25:59 pm
content: D'oh! Thanks, I think you might be onto something there dom0.Example 1 - page 24 "use a heftysolid-state relay(SSR, §12.7)"... I have read that § means 'section' so perhaps that was intentional?Example 2 - page 126 (Chapter review) "¶A. Pin-Labeling Conventions."Is yours the same?

author: Stupid Beard
author_rank: Regular Contributor
timestamp: April 13, 2015, 01:32:55 pm
content: Quote from: 74HC04 on April 13, 2015, 01:25:59 pm§ = section, ¶ = paragraph. They are using them to refer you to specific parts of the text. Nothing weird going on here.

author: 74HC04
author_rank: Contributor
timestamp: April 13, 2015, 01:39:41 pm
content: Quote from: Stupid Beard on April 13, 2015, 01:32:55 pmThanks for that. Methinks my initial flick through the book was a bit too brief! This must be the most embarrassing forum thread I have ever authored.To add to my embarrassment, I was once a trained typist!FWIW, these managed to confuse the heck of my colleagues too!

author: Stupid Beard
author_rank: Regular Contributor
timestamp: April 13, 2015, 01:47:57 pm
content: Quote from: 74HC04 on April 13, 2015, 01:39:41 pmIn fairness, this falls under the category of stuff that's easily forgotten through disuse.Still a bit funny though

author: tggzzz
author_rank: Super Contributor
timestamp: April 13, 2015, 02:04:49 pm
content: Quote from: 74HC04 on April 13, 2015, 01:39:41 pmI've never embarassed myself like that. Oh no. perish the thought. Never never never ever.(But the trick is to simply admit it and move on. Obviouslyyourealise that, but not everybody does!)

author: German_EE
author_rank: Super Contributor
timestamp: April 13, 2015, 08:51:17 pm
content: Nothing to worry about, I've just learned what § and ¶ mean from this thread and I've been seeing them for decades.

author: radioFlash
author_rank: Regular Contributor
timestamp: April 14, 2015, 02:03:56 am
content: The paragraph symbol is called a pilcrow. Now you can read all about it on Wikipedia!

author: Fred27
author_rank: Unknown
timestamp: April 14, 2015, 07:54:33 am
content: @radioFlash Thanks. That's exactly what I've just done, with some more sidetracking into other unusual typography and punctuation.
guitar amplifier with FV-1 DSP - project log - Page 1
Forum section: electronics / projects

author: kile
author_rank: Contributor
timestamp: June 11, 2020, 07:59:27 am
content: I am building a modular audio system. I want to use it mostly as a guitar effect pedal with an integrated power amp, but since the thing is going to be modular, I plan to add bluetooth audio in the future as well.Currently I have 5 modules:- guitar pre-amp with treble/mid/bass tone control- DSP audio processing chip FV-1 with an EEPROM (24LC32) for external programs- class D power amp; currently TPA3136D2 (2x10W)- mixer board which mixes the output of the DSP chip and the output of the guitar pre-amp- system power with an ATMega32 controller for switching DSP programs and displaying selected programEach module is on a 10x5cm PCB with a bus connecting them all together. They are stacked one on top of another and connected with spacers. The completed system will almost look like a beehive where the wax frames are the individual PCBs. I wanted to call it The Beekeeper, but that name is already taken, so I will have to come up with another beehive themed name. Any ideas?Except for the chips (power amp, DSP and op-amps) I want to make the PCBs as through-hole as possible. I have space, and I want to make it as easy to assemble as possible, so there is no need to go SMD. The power amp has a large cooling pad which sits on the bottom of the chip, and I have worked out a way to solder it to the board and have the PCB act as a cooler. More on that later.This is my current progresshttps://raw.githubusercontent.com/nodep/myAmp/master/docs/the_beekeper.pngThe project can be found here:https://github.com/nodep/myAmpThanks for reading!

author: kile
author_rank: Contributor
timestamp: June 23, 2020, 02:03:00 pm
content: I've finished routing the PCBs, ordered them, and now they are on the on their way from China. Yay!
The best way - Page 1
Forum section: electronics / projects

author: nucleopolymere
author_rank: Contributor
timestamp: December 11, 2016, 06:22:00 pm
content: Hi guys ,I am in my first year of electrical engineering now and I wanted to know what is the best way to build a high power signal generator like something aroung 30 to 50 khz and it could deliver around 100 W, Its is for building a ultrasonic cleaner with 2 50 W transducers. I just want the name of the circuit(s) so i can do my researches.Thanks

author: Benta
author_rank: Super Contributor
timestamp: December 11, 2016, 08:41:33 pm
content: For the power stage, LM3886 could be a choice.An oscillator for a signal source shouldn't be a problem to find.

author: Someone
author_rank: Super Contributor
timestamp: December 12, 2016, 12:45:56 am
content: There is no name of the circuit, you're asking for a very complex system.https://www.eevblog.com/forum/projects/signal-generator-for-ultrasonic-welding/Many parts are needed to deliver high powers to transducers.
The bloody datasheet stole my baby dingo!!!! - Page 1
Forum section: electronics / projects

author: TheRevva
author_rank: Regular Contributor
timestamp: October 16, 2015, 07:46:18 am
content: How many others out there get frustrated by the crappy info in _some_ datasheets (all too damned many IMNSHO)?Take for example something as SIMPLE as the LM2734 switching regulator.Here's a link to the TI datasheet:www.ti.com/lit/ds/symlink/lm2734.pdfIt's pretty obvious that this beast will do 'whatever it takes' in order to get the feedback pin (FB) to equal 0.8V or so.However, there's a WEE issue with the absolute max ratings table...The FB pin must be within -0.5V to 0.3V...Soooo, if the chip is doing EXACTLY what it's supposed to be doing, then BY DEFINITION, the FB pin must be somewhere near 0.8V which is about 0.5V above it's absolute maximum!Perhaps this is just the TI way to cover their butts from any potential customer problems?I can just imagine the phone call...Yes sir, we understand that you're having problems with our LM2734 in your PSU. Are you certain you've not exceeded any of the absolute maximum values?No? OK, please take a voltage reading on the FB pin...What's that you say? 0.8V? Sir, that's 0.5V above the specified 0.3V absolute maximum value on the FB pin for this chip. We cannot warranty our devices when you use them outside their specified absolute maximum values..Have a nice day!

author: amyk
author_rank: Super Contributor
timestamp: October 16, 2015, 08:36:14 am
content: I think they forgot the "Vin + ".

author: tszaboo
author_rank: Super Contributor
timestamp: October 16, 2015, 08:53:43 am
content: Bottom of every page: Submit documentation feedbackThis is a typo, it is not like other companies, which are lying or too optimistic in their datasheet.
The case of the annihilated cap!  -   Panasonic KX-T123210  - Page 1
Forum section: electronics / projects

author: hgg
author_rank: Frequent Contributor
timestamp: November 09, 2016, 03:37:25 pm
content: Hi guys,A friend of mine brought me his Panasonic kx-t123210 telephone exchange which stoppedworking after 16 years. I opened the power supply and this is what I found :After some cleaning with the garden hose... :Damage report: A broken diode, two wire-wound resistors broken off their pads and a broken transformerwhich I removed to check for damage.At first I thought that the transformer caused this damage but it checked ok (I think) and we werethinking of what else could have caused it until we noticed two leads sticking out of C106...This capacitor was annihilated during its explosion leaving no trace except for collateral damage and smoke.I was wondering if anybody with PSU experience could deduct from the surrounding componentsthe type and approximate value of the annihilated capacitor. I cannot find any service manual for this unit.Thanks!p.s. The huge power mosfet's heatsink was held on the PCB only with the mosfet's soldered leadsand two small dabs of glue... Solder pads were broken as expected. Good design Panasonic!

author: Assafl
author_rank: Frequent Contributor
timestamp: November 10, 2016, 02:03:41 pm
content: From the schematics here:http://elektrotanya.com/panasonic_kx-t123210_sch.pdf/download.htmlIt looks like C106 is a 10uF capacitor.There may be a better schematic somewhere else online (Elektrotanya happened to be open....). They also have a djvu version (which may or may not be different).Good luck!

author: hgg
author_rank: Frequent Contributor
timestamp: November 10, 2016, 03:20:38 pm
content: Indeed!From the schematic it looks like that it should have a 200V+ rating.I think that a 10uF 400V capacitor will be ok.Thank you very much !
The cautionary tale of chinverter - Page 1
Forum section: electronics / projects

author: Wartex
author_rank: Frequent Contributor
timestamp: November 14, 2011, 02:13:48 am
content: http://ludens.cl/Electron/chinverter/chinverter.html

author: EEVblog
author_rank: Unknown
timestamp: November 14, 2011, 03:06:46 am
content: Wow, what a shockerThanks for sharing.Dave.

author: IanB
author_rank: Super Contributor
timestamp: November 14, 2011, 03:32:00 am
content: When people buy cheaper mechanical tools from China like lathes or milling machines they usually expect that what they get is only a starting point, and that it will require extensive rebuilding to become a trustworthy tool. It sounds like the same is true of electronics...(And reading all the things you found wrong with it, and the the things you had to do to fix it, there is no way a device like that could successfully be designed by young inexperienced engineers. It would certainly take wise old heads to get that right, working in an environment where there was sufficient time to test and debug before going into production. The real cost of such a device is not in the parts, but in the time and salaries of the designers.)
The cheapest way to get 24V from 15 - 30V input - Page 1
Forum section: electronics / projects

author: bn
author_rank: Newbie
timestamp: September 18, 2020, 12:20:19 pm
content: I am looking for the easiest and/or cheapest way to get 24 V with input voltage 15 - 30 V. Maximum output current is 0.5 A max (though 0.2-0.3 A will be acceptable too). After quick browse through TI/AD website it seems that 4-switch buck - boost with discrete switches or SEPIC is the way to go. Although I've already used 4-switch controllers with success (LM5175/LM5176) I feel like it is a overkill for such application. SEPIC seems like the way to go. Is there a easier solution to what I'm trying to acheive? I don't care too much about board space, simplicity and cost are major factors.Thanks in advance

author: tooki
author_rank: Super Contributor
timestamp: September 18, 2020, 03:12:30 pm
content: Quote from: bn on September 18, 2020, 12:20:19 pmDid you try TI’sWebench Power Designer? You put in your key parameters and it spits out a list of circuits, which you can then modify, simulate, and output a PCB layout for. I used it for a number of designs recently and it worked great.

author: bn
author_rank: Newbie
timestamp: September 18, 2020, 04:19:08 pm
content: Quote from: MasterTech on September 18, 2020, 02:22:15 pmNot sure if it will work in this case since it is only boost type controller and I need to be able to step voltage down.Quote from: tooki on September 18, 2020, 03:12:30 pmJust did that and it spits out non-isolated flyback and indeed SEPIC. I guess I'll stick with the latter.I was hoping maybe someone would be familiar with IC similar to TPS55160 but with higher output voltage capability, because otherwise it would be ideal choice.

author: Benta
author_rank: Super Contributor
timestamp: September 18, 2020, 05:56:54 pm
content: SEPIC is a very good solution, especially when conducted EMI could be an issue.You should check ON Semiconductor as well for suitable ICs.
The correct way to have typical cheap DMM read AC V hert - Page 1
Forum section: electronics / projects

author: abdulbadii
author_rank: Frequent Contributor
timestamp: February 13, 2023, 05:09:23 am
content: How the correct way to have typical cheap DMM read AC V hertz as it'll display 000 as long as the either/both probe connected and a frequency, here in kilohertz, if it's disconnected, so what is the correct time length of the probe being connected before DMM gives a read frequency ?Problem is it seems the frequency given is inconsistent, varies on that time length of the probe being connected and problem too it's shown in short time while the "max/min" feature cannot be applied in this Hertz selectionPlease sincerely help of which the correct guide is really appreciated

author: tooki
author_rank: Super Contributor
timestamp: February 13, 2023, 08:08:02 am
content: It depends on the frequency, unfortunately. The meter basically counts the time of a few cycles, then displays the inverse of one period. So if the frequency is high, it’ll show the value very quickly, if it’s very slow it can take a long time.
The Cybertek's CK100 Injection transformer demo video. - Page 1
Forum section: electronics / projects

author: rbola35618
author_rank: Frequent Contributor
timestamp: November 19, 2024, 09:57:15 pm
content: This video was inspired by some of the post here in EEVBLOG. This is a start of a series of injection videos demonstration. In this video, I tested the CK100 injection transformer by Cybertek. I show a demostration of the CK100 taking a bode plot of my loop of my power supply. I also measured the input impedance of the injection transformer and finally measured the transmission loss to find the upper and lower bandwidth. The following demonstration videos series will include injection transformers from Omicron, Picotest, Tekbox and Ridley Engineering. Question or comments can be sent to rbola35618@aol.com

author: electron_plumber
author_rank: Regular Contributor
timestamp: January 16, 2025, 01:05:56 pm
content: Do you have a load connected when you do the s21 response? The presence or absence of the 5-10 ohm resistor commonly used for loop injection will change the result pretty drastically. E.g., the Blue Dot datasheet attached shows the response with and without it.
The DMM can measure high frequency transformer output can't? - Page 1
Forum section: electronics / projects

author: abdulbadii
author_rank: Frequent Contributor
timestamp: January 20, 2023, 03:42:06 am
content: Why can’t this cheap DMM measure the high frequency voltage transformer output inside a switching power supply?Is it just me or just "the money never lie" does evince?

author: xrunner
author_rank: Super Contributor
timestamp: January 20, 2023, 03:46:00 am
content: Quote from: abdulbadii on January 20, 2023, 03:42:06 amWhat cheap DMM are you referring to?

author: Brianf
author_rank: Regular Contributor
timestamp: January 20, 2023, 09:14:37 am
content: What does your meter's manual say about the upper limit of frequency for AC voltage measurement?

author: jonpaul
author_rank: Super Contributor
timestamp: January 20, 2023, 10:34:19 am
content: SMPS freq20khz ?50?100?1 MHz 10mhz?For a 120/240 mains the SMPS switches have 360V peak.most DVM are for mains frequency 50/60hz, the detection is designed to work to perhaps 1 kHz.Finally making any test, debugging an off-line SMPS requires scope, isolation transformers, current probes.Your post suggests that your experience is not sufficient for this kind of work.Jon
The electrically best solution for a stabilised 5V and 12V low current rail - Page 1
Forum section: electronics / projects

author: SK_Caterpilar_SK
author_rank: Regular Contributor
timestamp: March 18, 2019, 08:59:57 pm
content: So here I have a dillema about using a 7805 or 12 or to use just a shunt regulator. Since the current is not really that critical, I mainly want the input voltage range to be as wide as possible. THe purpose will be of powering two MCP602 one as a triangle oscilator and the other as a error amplifier and and PWM comparator. I also use a TC4420P to drive a IGBT on the output. The worst I expect it to pull 100mA (and thats with quite the headroom from the absolute maximum). Im not really concerned about the efficiency because its really negligible. But heres the question, do I go with a 7805 and a 7812 or just a simple shunt regulator. Also keep in mind that the whole thing works at 56kHz so I think the zenner would work best, I think. I made sure there 10nF bipassing caps undeneath all of the chips so should really matter that much.This is the most analog I could get with a PWM and the reason why? Well I built a 450V high power boost converter for a school project titled as "20W AB class vacuum tube amplifier".So far the biggest problem was to get it actually pump out some power and when I got it working now it just goes scarry to about 50W no problems with that small flyback tranformer not even bothering that much. The other reason why I did not go with a TL494 is that it is trying to hold the output voltage very tight which is mostly good but not in my case. It creates all sorts of weird duty cycle artefacts and actual audiable noise so its not ideal, so I wanted to make a relatively "soft" supply. It has been tested works like a treat so far only noise issues (not audiably but electrically, what I did not count for is that the high gain stage basically picks up this noise and amplifies it loading the output tubes and creating weird stuff but I also solved that).If someone wants to see the completed thing I can send a pic.Apologies for the crappy grammar, im slovakian please dont judge meThanks.

author: chemelec
author_rank: Contributor
timestamp: March 18, 2019, 09:15:33 pm
content: Either a 7805 or a 7812 should work OK.

author: SK_Caterpilar_SK
author_rank: Regular Contributor
timestamp: March 18, 2019, 09:39:06 pm
content: Quote from: chemelec on March 18, 2019, 09:15:33 pmI kind of want the best of the best instead of should work ok. I want the signals to be 100% clean and clear because this is a demonstration piece and who knows maybe even a production model lol.

author: jaycee
author_rank: Regular Contributor
timestamp: March 18, 2019, 11:28:31 pm
content: LM317 will have higher quality regulation of the output, especially if you use a 10-22uF capacitor on the ADJ pin.If you want to go overboard stick an R-C filter before it.http://www.tnt-audio.com/clinica/regulators_noise2_e.html
-The elegance of the dynamics of electronics - Page 1
Forum section: electronics / projects

author: John Heath
author_rank: Frequent Contributor
timestamp: October 07, 2018, 08:55:31 pm
content: I was watching a video on wave theory from the 1950s. This video always puts a smile on my face. I wanted to share this smile with others in this group. This guy really understands the great contribution of Oliver Heaviside's book " telegraphers hand book" from 1890. Enjoy.

author: Wolfgang
author_rank: Super Contributor
timestamp: October 07, 2018, 11:38:58 pm
content: Very nice film !

author: John Heath
author_rank: Frequent Contributor
timestamp: October 08, 2018, 08:27:45 am
content: I like the part where a sudden impedance change in the middle will cause an expected reflection but the gradual impedance change that is as long as the wave length acts like an impedance matching transformer with no reflection. I wonder if that technique for impedance matching has ever been used in electronics. I can not think of an example of it.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 08, 2018, 10:14:45 am
content: Quote from: John Heath on October 08, 2018, 08:27:45 amEasily found,https://www.microwaves101.com/encyclopedias/tapered-transformershttps://en.wikipedia.org/wiki/Horn_antennahttps://en.wikipedia.org/wiki/Vivaldi_antennaetc.Tim

author: Wolfgang
author_rank: Super Contributor
timestamp: October 08, 2018, 10:52:20 am
content: Of course it exists. Is called tapered transformer. Can be used for striplines or waveguides.

author: John Heath
author_rank: Frequent Contributor
timestamp: October 09, 2018, 12:29:52 am
content: The best analogy I can think of for the tapered type micro wave impedance matching would be a bull whip. As a wave travels down the bull whip the whip diameter is becoming smaller therefore inertia is less , less inductance , which will increase wave velocity. By the time the wave reaches the end of the whip the velocity is really fast causing the snapping sound at the end where the whip stops.
The endless connector hunt -40/105C IP rated 1-5A - Page 1
Forum section: electronics / projects

author: Simon
author_rank: Unknown
timestamp: April 03, 2014, 09:32:09 am
content: We normally use Deutsch DT series connectors but these are big and made to take power stuff as they are rated up to 13A. What I not need is something similar but smaller to carry low power and signals.Deutsch (TE) did release a mini series of connectors (series 369) but they are even more expensive than the original DT series and we care little for their aerospace credentials.Any suggestions ?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 03, 2014, 09:52:54 am
content: Quote from: Simon on April 03, 2014, 09:32:09 am"IP rated" means nothing - IP what?Bulgin mini/micro buccanneer are quite good but fiddly to assemble.Another option I recently discovered are M12 connectors for industrial sensors etc. Nice thing about these is you can buy ready-made cables with moulded plugs fairly cheaply.

author: Simon
author_rank: Unknown
timestamp: April 03, 2014, 10:22:53 am
content: Well something like IP67 but let's start with actually having a seal, I just spoke to one cable supplier we use and he uses a lot of superseal from TE which I'm going to investigate.

author: DaveW
author_rank: Frequent Contributor
timestamp: April 03, 2014, 12:08:03 pm
content: Mighty mouse connectors from Glenair are fantastic-not as big as they look in the pictures and fantastic quality, proper mil-spec connectors,http://www.glenair.com/mightymouse/size_8_contacts/index.htm

author: Simon
author_rank: Unknown
timestamp: April 03, 2014, 12:22:28 pm
content: Hm to be honest they look like they could be expensive. I've been looking at superseal which look good and cheap and TE have just emailed me back with some information on their new slimseal SSL connectors that look quite good. SSL is supposed to stand for Solid State Lighting, I think their marketing office need a kicking - if it carry's current who cares what it goes into providing it will work in the environment.
the fabled 'horoclamp' - Page 1
Forum section: electronics / projects

author: zumdar
author_rank: Newbie
timestamp: October 19, 2021, 05:44:27 am
content: hello ee heads!while trying to find the perfect overvoltage clamping circuit for my project i was reading the art of electronics (as you do)... and in section 9.13.1 they mention a wonderful solution to all my problems, a low voltage clamp-crowbar. Alas! exactly what i need. it clamps.. and it throws in the crowbar if things get really bad?? yesss! but it was a tease.. it is too advanced for this 1000+ page tome and is relegated to AoE x chapters...but then doing a quick search i come across this beauty:http://seti.harvard.edu/unusual_stuff/misc/crowbar.htmand it even has a big honking relay just like the sucker i am trying to protect my circuit from.does anyone have the schematic for this magical clamper?!?thank you!!