hybridfree/eevblog-posts huggingface dataset:
some advice on designing for limited space - Page 1
Forum section: electronics / projects

author: kubuni
author_rank: Newbie
timestamp: September 26, 2017, 03:43:28 pm
content: I'm designing a Smart LED Bulb, which seems to be a pretty simple project so far. I have a nice IC buck LED Driver that accepts Input 40V. It has a pwm pin to change the brightness that I'm driving with a bluetooth chip. The bluetooth chip can be powered by 3.3V; the real range is like 0 to 3.6 then goes through some internal LDO or optionally a DC/DC. Since Space is critical, Would it be possible to get a small transformer with 2 secondary coils then use some resistor -zener divider to supply power to the bluetooth module?I got the idea from this PDF to use the resistor-zener.http://www.newark.com/pdfs/techarticles/microchip/3_3vto5vAnalogTipsnTricksBrchr.pdf

author: Kleinstein
author_rank: Super Contributor
timestamp: September 26, 2017, 04:16:06 pm
content: Normal 50/60 Hz transformers don't work well in small size. Everything below about 1 VA is usually pretty bad (e.g. higher no load loss of around 1 W) so they hardly get smaller even if just 0.1 VA. In theory one can get a little better with expensive custom ones. For low power a capacitive dropper (especially at 110 V) might be more interesting. Switched mode supplies also work reasonable well at low power, especially when starting from 40 V DC.

author: Rerouter
author_rank: Super Contributor
timestamp: September 27, 2017, 12:12:06 pm
content: You left out wattage and voltage on the LED string, knowing these 2 could help,as its a "LED bulb" I am going to guess it will be in the ballpark of 7-15W electrical power used,Are you sure you cannot get by with a mains buck converter, rather than a 40V limited one?In the past i may have just gated a thyristor on the tail end of the waveform to keep the rectified voltage low, but this looks a bit ugly on emissions tests.
Some assistance finding FET replacements - Page 1
Forum section: electronics / projects

author: cybermaus
author_rank: Frequent Contributor
timestamp: March 01, 2025, 07:59:47 pm
content: I cannot find anything on these two FET's with labelFXN30S60FThey drive the primary side of a Lab Supply in a half H bridge, have some gate driving stuff around them, and are fully internally shortedIt happened when I accidentally shorted the outputs, the two leads casually rubbed, there may have been many on/off spikes, and the snubber circuit may not have been enough.The supply *should* be short-protected, and I did purposely short it before while low voltage injecting, but the casual rubbing at 12V it did not like.The number and context likely make likely the FET are IGBT of 30Amps 600VOr so I think, do correct me.Anyone is a better googler then me and can find specs?And if not, should I simply go forany of these?Edit: I think I'll gowith this one

author: moffy
author_rank: Super Contributor
timestamp: March 01, 2025, 08:59:07 pm
content: A quick Google search:https://alltransistors.com/mosfet/transistor.php?transistor=69625
Some Older Chip Images - Page 1
Forum section: electronics / projects

author: mawyatt
author_rank: Super Contributor
timestamp: May 08, 2020, 05:11:44 pm
content: Here's a few more chip images in very low resolution, imaged awhile back.Best,More at Nikon Image Space, be sure to download files for full resolution. Note the last image is a wafer sliver from a old abused wafer, this was test of the S&S system mentioned and is ~28,000 pixels by 22,000 pixels.http://img.gg/taIZ99MMike

author: tggzzz
author_rank: Super Contributor
timestamp: May 08, 2020, 07:31:57 pm
content: Very pretty.Here are some Burr Brown hybrids from the late 70s.https://entertaininghacks.wordpress.com/2015/07/07/images-of-late-70s-burr-brown-thick-film-hybrid-ics/For example

author: mawyatt
author_rank: Super Contributor
timestamp: May 09, 2020, 04:53:47 pm
content: Those old BB hybrids are excellent performers and make nice images as well.I remember we were using a BB hybrid Precision 18 bit DAC way back in 70s, this had few chips, one of which was a CMOS chip, and was a very expensive hybrid. The CMOS chip was prone to latchup if the substrate became only slightly forward biased. We found this out because a few burned up (actually melted a hole in the package top) because during power up a small "glitch" could forward bias the CMOS substrate, which would go into SCR latchup and burn up. A couple protection SB Diodes solved the problem after we had a few fried expensive hybridsBest,
Some chip suggestions? - Page 1
Forum section: electronics / projects

author: JVR
author_rank: Regular Contributor
timestamp: October 22, 2012, 12:45:22 pm
content: I need to build a small (read +-2x2cm) power supply module, it will run off different batteries, depending on what is a available. Max voltage would be ~30V and lowest ~5V, drom this I need to generate 12V @ 500mA.Had a quick squizz at TI's webbench, but would like to get some real world info, so if you've used a chip in this category, give me some feedback please.JVR

author: Kremmen
author_rank: Super Contributor
timestamp: October 22, 2012, 12:51:16 pm
content: TI's MC33063 / 34063 comes to mind... Did exactly that some time ago using this chip.
Some evening toying with class-D amp... doesn't oscillate! - Page 1
Forum section: electronics / projects

author: Yansi
author_rank: Super Contributor
timestamp: December 07, 2015, 12:17:31 am
content: Hello guys,today evening I started toying and breadboarding with some "oldschool" class D technology based on LM311 self oscillating comparator. I have successively built the circuit (on a piece of veroboard), starting from the power circuitry, gatedriver, small voltage supply, level shifter and comparator. Each building block was tested separately and seems working well. Until the last block was added: The comparator. (detailed description of the circuit see below)I have a problem that the circuit cannot start oscillation without external help. The problem was traced to this point: After power-up, the comparator tries (always) with output positive (i.e. wants the highside mosfet to switch on first) - but this is impossible with discharged bootstrap. If I take an external PSU and give the bootstrap cap a shot, it starts and runs freely and very stable after removing the external bootstrap supply. (That means there is no problem with feedback polarity - for those who may want to ask that one)The problem is only starting the oscillation by always turning on the high side mosfet.What do you guys think might be the solution for this problem? Do you have any ideas?Here is a more detailed description of my circuit. I have based my on this one (see attachments). I have made only some minor modifications. All component values were calculated by me. I also do not have the original values for the schematic.The main changes I have made: IRFB4019 mosfets (much better!), 3x2N5401+BC557C in the diff. stage / current source, the comparator is running at +-9V (have had such zeners available). The most important change is near the base of Q4. The base is supplied from a voltage divider, slight positive voltage (~0,9V) to be sure the comparator saturation voltage is low enough to flip the differential pair reliably. The divider is supplied from base of Q2 (colletor of Q1). The current source is always ON, therefore R6 is omitted.Do you have any ideas how to define in the circuit so that the oscillation always starts by switching on the lowside fet?The only reasonable I can think of now is to purposely increase the comparator offset to a such polarity, it will always start with low pulse...Thank you for suggestions.If needed I will draw the exact schematic as I have built it.//EDIT: Have drawn the exact schematic.

author: Cyberdragon
author_rank: Super Contributor
timestamp: December 07, 2015, 05:09:57 am
content: You could use an RC circuit across the power rail that biases a transistor to off when the capacitor is charged. This would be used to hold the circuit low for an instant on power up then let it free run.
Some PLL help if you please - Page 1
Forum section: electronics / projects

author: JVR
author_rank: Regular Contributor
timestamp: August 25, 2014, 11:48:49 am
content: Hi Gents, so leading on fromthistopic, I now need a PLL that will take a sub 100KHz input at a ~7% duty cycle, and give me an output north of 5Mhz with a 50% duty preferred.I've looked at the old school 4046, but it can output a max of 1Mhz, I'm also looking at the SN74LS297, but I'm unsure what it will think of the low DC input signal. I cant seem to find any modern PLL chips that will take a <1Mhz input signal, and I'd much prefer not to have to cascade the chips.So please, ye gods of high speed circuity, help a brother out.Thanks!JVR

author: fcb
author_rank: Super Contributor
timestamp: August 25, 2014, 12:41:04 pm
content: Use a 74HC4046 - good for over 10MHz

author: David Hess
author_rank: Super Contributor
timestamp: August 25, 2014, 05:39:15 pm
content: Or use the 4046 with an external VCO.
Some Projects take a look ! - Page 1
Forum section: electronics / projects

author: c_francof
author_rank: Newbie
timestamp: December 21, 2012, 10:03:41 pm
content: Well, this is my second post here ! i have done different projects all about related to FPGA, artificial vision, robotics and hardware stuff...Here are some old links i would like to share with you.1.Touch demo of my development kit SDKTFTV1.0 HCS08GB32, this time making a touch Paint DEMO, excuse for the low resolution of the cam, i will try to do it on HD cam next time. 8 bits microcontroller running at 4Mhz good challenge to paint on a 320*240 res TFT.2.Same kit, but this time doing a demo of the Radio transceiver module CC1101 with an accelerometer(all made in home ^^)3. Small osciloscope with a Nokia 6100 LCD screen, running on a 8 bits microcontroller.4. Using the 6100 LCD Screen ,Radio transceiver and a FPGA receiving and playing from a SD Card mp3 songs ... Touch controller etc5. Some artificial Vision of my old Robot using the Spartan 3E starter kit and a 15 dollars cheap camaraThere are more projects, hope you enjoy and comment . Cya

author: Mechatrommer
author_rank: Super Contributor
timestamp: December 21, 2012, 10:40:59 pm
content: ok the robot vision is cool.
Some questions! - Page 1
Forum section: electronics / projects

author: facumedica
author_rank: Contributor
timestamp: April 11, 2014, 01:59:21 am
content: Hey guys! I have some questions, I want to hear your thoughts, opinions...1. What kind of ADC a top of the range oscilloscope uses? Especific examples? (Part numbers?)2. How difficult is to design a computer like the RaspPi? Someone put it into a custom PCB already?Maybe you realised what I want to design...Thanks!

author: BravoV
author_rank: Super Contributor
timestamp: April 11, 2014, 02:02:51 am
content: Quote from: facumedica on April 11, 2014, 01:59:21 amI have a question too, what is your skill or experience in electronics ?No need lengthy explanation, just a short & brief on example projects you've done in the past is enough.Your easy answer here may help others in helping to answer your questions.

author: w2aew
author_rank: Super Contributor
timestamp: April 11, 2014, 02:07:31 am
content: Quote from: facumedica on April 11, 2014, 01:59:21 amAs for your first question, the premier manufacturers like Tektronix and Agilent, design their own custom ADCs. I can't speak to what the other manufacturers use.If your thinking of designing your own oscilloscope, just remember there's a lot more to it, such as a low noise preamp/attenuator front end for each channel, precise timing/sampling control, comprehensive triggering control, fast sample memory demuxing and display processing - to name a few.

author: Monkeh
author_rank: Super Contributor
timestamp: April 11, 2014, 04:00:00 am
content: Quote from: facumedica on April 11, 2014, 01:59:21 amTry it and see.

author: facumedica
author_rank: Contributor
timestamp: April 11, 2014, 09:49:52 am
content: Quote from: Monkeh on April 11, 2014, 04:00:00 amI like that answer!I am not talking about making it right now, maybe make it a long term project, so I can learn while designing. (Maybe it won't reach even the prototype stage, just designing it for fun!)

author: SL4P
author_rank: Super Contributor
timestamp: April 12, 2014, 04:14:54 am
content: That's exactly the way we all started!It's how you fill your parts box - with all those good bits that were going to be a ...!

author: KerryW
author_rank: Regular Contributor
timestamp: April 12, 2014, 04:32:11 am
content: The youth gets together his materials to build a bridge to the moon, or, perchance, a palace or temple on the earth, and, at length, the middle-aged man concludes to build a woodshed with them.Henry David Thoreau

author: facumedica
author_rank: Contributor
timestamp: April 12, 2014, 04:52:29 pm
content: KerryW look at my signature! That quote is very descriptive! I've never read that one until nowThanks for all your replies, I think I will continue with my research!Cheers!
Some questions for my project - Page 1
Forum section: electronics / projects

author: Ax_6
author_rank: Contributor
timestamp: April 27, 2013, 11:19:37 am
content: Hello! I'm working on a project which became a real challenge for me. What I want to do is create an array of 128 RGB LEDs so that I can make a sort of display. The basic control at the moment is done, so I'm able to run the LEDs with some commands sent to the controller: for that I'm using a PIC18F4450 plus some other chips. At the moment I have two main questions (one isn't that much electronic...oh well):1.What I want to do now is adding another pic microcontroller that handles the entire control of the system. This micro has to:Send commands to the display controller through a 9bit bus.Send a signal with a PCM modulation to two speakers (obviously there is the amp in between).Read a micro SD (already have a good library that I've made some time ago for it).Do the FFT on the samples, so I can make some cool effects.Finally it needs some KB of RAM since I wanted also to implement a sort of layer structure for the images printed on the screen.Could you advice me a PIC that can easily do all this stuff?2.The other question It's about the screen itself, it's a bit more "physical". What I'm trying to find is a good light diffuser for the LEDs. Until now I found a really good diffuser in a samsung LCD, unfortunately it's too small for the final project and just enough for the prototype. Here some pictures with and without the magic diffuser:pic1pic2pic3pic4Do you know where I could find something like this? (and.. no, I can't go to my local dump they do not allow anyone to take anything...) It has to be at least 97x49 cm.Thanks!!

author: MacAttak
author_rank: Unknown
timestamp: April 27, 2013, 10:58:52 pm
content: For the diffuser, you could probably use that flimsy plastic diffusion cover material that is used in overhead fluorescent lighting. I think it's pretty cheap stuff and easily obtained from your local home maintenance store.I think that's what was used in this project:http://www.kickstarter.com/projects/2113011562/programmable-intelligent-led-development-system-pi

author: Ax_6
author_rank: Contributor
timestamp: April 28, 2013, 05:15:59 pm
content: Thanks, I was able to find justthis... seems good but too small. I don't think that the acrylic used in that project is really what i'm looking for...it isn't smooth at allAnyone got other suggestions? Also on the PIC to use? =D

author: glatocha
author_rank: Regular Contributor
timestamp: May 06, 2013, 04:28:51 am
content: about the PIC.In my opinion the selection table on the microchip page:http://www.microchip.com/ParamChartSearch/Chart.aspx?branchID=1012is one of the best I've seen.You can find on your own what you really need.Just don't open this new "Advanced selector tool" this really sucks
Some Si5351 spectrum measurements - Page 1
Forum section: electronics / projects

author: dcarr
author_rank: Regular Contributor
timestamp: July 10, 2015, 05:37:48 am
content: Hi eevblog,I recently had a Si5351 hooked up to my spectrum analyzer and took a few measurements. My particular application needs a VHF LO and I was curious how clean the Si5351 is.Here's a shot centered at 146.72MHz with 25MHz span:You can see a fairly large spur (-46dBc) offset 3.26MHz on both sides along with a fair number of other signals.Here's a shot of the first few harmonics:The second harmonic is -16.1dBc and the third is -11.7dBc.Lastly, the harmonics out to 3GHz. Still a respectable -36dBm signal way out there at 2.7GHz!I also took some measurements near 12.2MHz and 5.1MHz and found the situation to be much better. No screenshots unfortunately but there were minimal/no visible spurs at those frequencies.Hopefully interesting information for some.David

author: mvdswaluw
author_rank: Contributor
timestamp: July 10, 2015, 08:29:30 am
content: Not really surprising as the SI5351 outputs a square wave...
Some tweaks on DS2072A, backlight and noise.  - Page 1
Forum section: electronics / projects

author: Emi
author_rank: Contributor
timestamp: March 10, 2016, 06:42:01 am
content: Hi. .I'm very happy to be an owner of this great scope ( full option hacked) but I'd like some improvements. .-Im a bit disappointed can't dim panel backlight. .it's too bright for me ! trace and grid dims but bl not? Why?is there a way to mod this? ( even opening/cutting/ soldering something)-Can i improve input noise shielding cables or chips?Its always about 2mV pp..really too much !i think psu wires could be the cause...Should i put ferrite cores everywhere?Can You give me some hints?

author: ElektronikLabor
author_rank: Regular Contributor
timestamp: March 10, 2016, 09:53:18 am
content: Quote from: Emi on March 10, 2016, 06:42:01 amYou could use an 555 timer as an pwm; the circuit would be quite simple and small. Then you could control the backlight by a potentiometer; but you have to drill a hole for the potIt would be cool, if the scope automatically dims the screen in dependence on the ambient light, like any mobile phones already doesFor that you need some kind of photosensor which is mounted on the outside of the scope and a circuitry which convert the signal of the sensor to a PWM.If you don't need the option for adjusting the brightness after modding, it's even simpler.1st possibility: The LEDs are driven by a voltage source with current limmiting resitsor(s); change the reistor(s) to a higher value.2nd possibility (more unlikely): the LEDs are driven by a current source; change the sense resistor which adjusts the current value to a bigger one.Quote from: Emi on March 10, 2016, 06:42:01 amYes it could be possible, but for that you must know the source of the noise. If it would be easy I think Rigol did it already by themselvesIf you think it'ss the wires, then you could check it by adding some noise on the wires (e.g. via a transformer) and watch if something changes.

author: Emi
author_rank: Contributor
timestamp: March 10, 2016, 10:26:36 am
content: ThanksBut let me know. ..I thought BL was lamps. .not ledsAnyway your suggestions for 555 are cool (i've just put on a breadboard a similar circuit..with a fotoresistor sweeps the DC...) but i wouldn't add more noise inside. ..Is panel directly feed from psu?In this case a resistor o strong pot on the right wire could be perfect for me...but ..which wire?If only electric schemes of this stuff were avaiable
Some weird results in precompliance - Page 1
Forum section: electronics / projects

author: pisoiu
author_rank: Regular Contributor
timestamp: November 17, 2022, 10:19:55 am
content: Hi,I am doing some precompliance tests for a DC powered device, using MCP16301 SMPS at 27 volts. I am measuring conducted emissions with 2x lisn and R3131A spectrum analyzer.My smps have a pi filter with 2.2uF+4.7uH+2.2uF. Coil is from wurth, WE-LQ series, part # 744045004.Here are 2 captures, one with the coil placed in one way, the other with the coil reversed. Why are there differences in attenuation level depending on coil mounting direction, I don't get it?I tried with other close inductor values, same effect, all other conditions are identical.

author: jonpaul
author_rank: Super Contributor
timestamp: November 17, 2022, 10:48:54 am
content: schematic? Pinout, symbol of indr? CM choke or NM choke?j

author: pisoiu
author_rank: Regular Contributor
timestamp: November 17, 2022, 11:44:06 am
content: L2 is the inductor, it's an unshielded 1812 inductor.https://www.we-online.com/catalog/en/WE-LQ#/articles/WE-LQ-1812

author: mag_therm
author_rank: Frequent Contributor
timestamp: November 17, 2022, 07:24:46 pm
content: If I understand your query,that might be because the coil has a start inside on the coil, inner layer, and a finish on surface of the coil, outer layer.The capacitance to other components will be higher on the finish terminal. From the drawing, the finish winding should be visibleUse it in the orientation that gives best results.

author: Kleinstein
author_rank: Super Contributor
timestamp: November 17, 2022, 10:50:22 pm
content: With 2.2 µF on both sides of the inductor, parasitic capacitance should be less of an issue. Chances are the inductor will have quite some magnetic stray field and copper traces or other metal close to the inductor can effect the inductance. For the given coil the field should be relatively symmetric and a large effect is surprising. There could be an magnetic interaction with the near by ferrite bead. Getting quite some effect from small changes can happen if there is a resonance involved. Getting to close to a resonance can be a problem and also cause more random variations between different units. Chances are the 2.2 µF are MLCC and thus susceptable to a reduction in capacitance from DC bias. So it is hard to calculate the actual capacitance and resonces.Soldering could also effect the MLCC, by resetting aging effects.With the rather sharp peaks there can also be an effect of the exact postion of the frequency bins. The peak values can show some variations depending on whether the actual maximum exactly hits a frequency bin or the power is split equally on 2 bins. The actual SMPS frequency can drift during the measurement and between the 2 test. So there can be some variations from the way the measurement is done. Peak values are naturally scattering a bit.
Somebody please explain what I'm doing wrong - Page 1
Forum section: electronics / projects

author: alexwhittemore
author_rank: Frequent Contributor
timestamp: January 08, 2012, 06:04:03 pm
content: If you could, take a look at the picture I've attached.Yesterday I found a microwave being thrown out, so I immediately harvested its transformer. HV win! I was playing around with it today to see what it could do, so I hooked a function generator to the primary and scoped that vs the secondary. The function generator is on scope channel 1 via aligator leads (so 1x, 1Mohm input), the secondary is on channel 2 via a 10x probe, and another 10x probe is metering the secondary on the multimeter.Here's my confusion. If you'll notice, the secondary is reading 20Vpp on the scope = 200Vpp. The meter, via the 10x probe, is reading 5.5Vrms = 55Vrms. But last I checked, 100V / 1.414 = 70.72Vrms. So assuming the secondary output is, in fact, a good sine wave (and it looks so), one of those two measurements is wrong. I trust the scope, but I also trust the meter, which leads me to ask if my measurement setup is somehow flawed.

author: IanB
author_rank: Super Contributor
timestamp: January 08, 2012, 06:37:13 pm
content: Quote from: alexwhittemore on January 08, 2012, 06:04:03 pmIs the 10x probe on the multimeter specifically designed for that meter, or is it a scope probe? It is highly unlikely that a scope probe will correctly couple to a normal multimeter. The multimeter input arrangements (resistance, capacitance) are different.

author: Rufus
author_rank: Super Contributor
timestamp: January 08, 2012, 06:42:53 pm
content: A x10 probe is only x10 when feeding a 1M ohm input and, at moderate frequencies up, when compensated to match the capacitance across the 1M.Your meter is about 10M ohm and 100pF which would make a x10 probe about x2 at dc, and probably about x100 at high frequency. You seem to be running at 14kHz (way high for a big iron cored transformer) and it looks like the probe is about x13 there.

author: alexwhittemore
author_rank: Frequent Contributor
timestamp: January 08, 2012, 07:12:37 pm
content: You guys were right, I hadn't considered that the probe is only 10x driving a 1Mohm load. When I pulled the probe out and used a clip lead, everything looks as expected.As for the frequency, it's actually half that. Note that the cursors are set up to get a peak to peak voltage measurement, which is actually a half cycle. So the 1/T measurement is high by a factor of two.You're right, the transformer is meant for 60hz, but it happens that the system is resonant at that frequency of almost exactly 7khz.
Someone help me understand how this circuit works please - Page 1
Forum section: electronics / projects

author: angelothewolf
author_rank: Contributor
timestamp: April 19, 2014, 03:05:16 am
content: It is a 3-band equalizer circuit, with sweepable mid ranging from 350 hz to 5 khz. the low cut is fixed at 100hzSo the idea is to add a switch to change the bass freq, from 100hz to 80hz or something like that.Im requesting a little help to mod this Eq, im not quite understanding the circuit. Are that 2 33nf caps responsible for the low freq cut?thanks

author: angelothewolf
author_rank: Contributor
timestamp: April 19, 2014, 03:11:45 am
content: actualy its a vintage YAMAHA 2408M, if someone want to know.btw im replacing this jrc4558 with OP275 and recaping too!

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: April 19, 2014, 03:14:51 am
content: Hi,The Hi and Low controls resembles the famous Baxandall circuit.See this link:http://headwize.com/?page_id=741The circuit has been modified to add the MID control.Jay_Diddy_B

author: angelothewolf
author_rank: Contributor
timestamp: April 19, 2014, 03:52:17 am
content: ohhh! god bless you

author: w2aew
author_rank: Super Contributor
timestamp: April 19, 2014, 04:14:23 am
content: Quote from: Jay_Diddy_B on April 19, 2014, 03:14:51 amIt's also the same basic bass/treble control circuit (without the midrange addition) that I used in my little microphone preamp/eq that I built for use with an old crystal mic and my ham radio. See this video for a little demo on how the circuit works:

author: angelothewolf
author_rank: Contributor
timestamp: April 20, 2014, 01:49:10 pm
content: Ok thanks everyone for the answers! now i know what a baxandall circuit is!So i put a dpdt switch to change the two 33n caps to 100n, now i got two options for the low freq control of this console
Someone knows the type of those PCB headers? - Page 1
Forum section: electronics / projects

author: davorin
author_rank: Unknown
timestamp: March 01, 2025, 09:30:38 am
content: Good morning (o;Does someone know what kind of PCB headers those are below?The pitch is 4mm, but Digikey nor Mouser have anything like that, nor does Google image search come up with any results that would match.

author: David_AVD
author_rank: Super Contributor
timestamp: March 01, 2025, 09:53:57 am
content: They look like the JST 3.96mm ones. The header shell is a VHR-2N-BK for the 2 pin type. You should be able to find the male pcb header from there.

author: davorin
author_rank: Unknown
timestamp: March 01, 2025, 10:06:56 am
content: Perfect, thanks :-)My fault I was searching for 4mm pitch and not 3.96mm (o;
something I made on tuesday - Page 1
Forum section: electronics / projects

author: firehopper
author_rank: Frequent Contributor
timestamp: March 22, 2013, 10:46:35 am
content: http://www.flickr.com/photos/firehopper/8571797873/#in/photostream

author: 4to20Milliamps
author_rank: Regular Contributor
timestamp: March 22, 2013, 10:54:30 am
content: I bought my oldest son a Pi for christmas because they are using them in a class at school, I wish I would have had cool stuff like that in school.what you can with 50 bucks nowadays is pretty amazing.I would be interested in seeing your project as it progresses.

author: firehopper
author_rank: Frequent Contributor
timestamp: March 22, 2013, 10:42:28 pm
content: yeah I wish, we had atari 800xl's and base 8088'sI have to add cooling, and a touch screen to that lcd yet.

author: americanhacker1
author_rank: Newbie
timestamp: March 29, 2013, 08:27:06 pm
content: Looks great i had a similar idea for the pi but i wanted it to just be on a laptop and all be one portable unit
Something with the GreenPak3 - Page 1
Forum section: electronics / projects

author: asgard
author_rank: Regular Contributor
timestamp: February 11, 2016, 09:43:55 am
content: Hi, Dave.Thought you should have a look at this. It is a Launchpad MSP430 daughter board for implementing a complete reflow controller. It uses one of the GreenPak 3 chips you got recently as a quadrature to SPI bus converter (plus ambient temp sensor and variable-speed fan controller). The .GP3 file can be downloaded from my site,http://www.bifrost-group.com. It also marks the first somewhat significant and useful project using Altium CircuitMaker instead of Eagle. The timing diagrams and other material on the converter is available in the documents section of the web site.CheersJ.R. Stoner
Sometimes it is that easy! - Page 1
Forum section: electronics / projects

author: itdontgo
author_rank: Regular Contributor
timestamp: June 18, 2014, 11:10:23 am
content: The guy in the cafe showed me his stuttering TV flicking on and off. I knew what that would be!

author: itdontgo
author_rank: Regular Contributor
timestamp: June 18, 2014, 11:12:14 am
content: They were paralleled up on the 5v rail so both were knackered.
Sometimes you need more power on the bench - Page 1
Forum section: electronics / projects

author: Rolo
author_rank: Regular Contributor
timestamp: October 11, 2015, 03:58:06 pm
content: Just showing my newest PSU. I'm not going to win any beauty contests with it but it has the power ! I have a linear 0-30V/3A PSU for normal use, but sometimes you just need more. I found this Delta Elektronika S28-10 switching PSU for a low price and I knew it had the option to regulate it with external potmeters and it has an 0-5V output linear to the current drawn. So I made a front end for it using parts that I already had, except one 10 turn potentiometer and the transformer for the meter that I had to buy. The meter is my own design, it's an modified version of the one I made for my Delta E030-3 PSU. Works great, two ten turn pots to regulate the Amps and Voltage. This one gives a real 10 amps and is happy to do that continuously, no fans so it's quiet. It gives 0 - 10 A / 0- 28 V.

author: xReM1x
author_rank: Regular Contributor
timestamp: October 11, 2015, 05:17:30 pm
content: the voltage & current regulation is all inside the psu?

author: SeanB
author_rank: Super Contributor
timestamp: October 11, 2015, 05:31:55 pm
content: Good use of an existing supply. Not going to win any safety awards, and not meant for use by the general public, but still a good solution to a need you had.If you opened it up you would have found internally a 12V supply for driving the LCD side on a secondary supply, used by the control circuitry, but the external one is still quite nice there.

author: Rolo
author_rank: Regular Contributor
timestamp: October 12, 2015, 02:36:07 pm
content: Quote from: xReM1x on October 11, 2015, 05:17:30 pmYes al inside the unit. I did not open the PSU for modifications.Verstuurd vanaf mijn SM-G903F met Tapatalk

author: bitseeker
author_rank: Super Contributor
timestamp: October 13, 2015, 02:00:41 am
content: Nice job, Rolo. I especially like the bar graph you added to the LCD character display. Great idea. How much resolution do you get?

author: Rolo
author_rank: Regular Contributor
timestamp: October 14, 2015, 04:58:08 pm
content: Quote from: bitseeker on October 13, 2015, 02:00:41 amThe top one is 1 bar = 1 Volt, the end bar is at 30V.The bottom one is 1 bar = 0,25 A, end bar is at 10A.It did this using user defined characters.The graph updates much faster as the digital readout and helps to see trends in current or voltage. Also very usefull to see it you reach the CV/CC toggle point.Works very nice in practice.I have one minor issue, the amp meter is a bit unaccurate in the lower range, say under 0.5 Amp. Not sure why, when I attach my DMM to the Imon output it's spot on, so must be the ADC in the ATmega328 or the software. It's no big deal, I won't be using this PSU in the low amps range a lot.

author: bitseeker
author_rank: Super Contributor
timestamp: October 14, 2015, 05:14:25 pm
content: I like it. Cool feature implemented economically. The higher update rate for the graphs is very much like the handheld DMMs.
SONAR - Rouge signal and Filter issues  - Page 1
Forum section: electronics / projects

author: paltanuoto
author_rank: Newbie
timestamp: July 07, 2025, 09:18:12 am
content: Hi guys, I need your help! It's my first time building electronic circuits and I'm really struggling as I'm a total noob when it comes to electronics.I'm building a SONAR and I'm using an Arduino Due (mainly due to its higher ADC speed, as the sonar works at 25kHz). I've checked the entire transmission line and I'm sure that everything there works fine.Analyzing the receiving line, though, I noticed a couple of strange things. Since I don't have an oscilloscope, I'm using the analog pin of my Arduino to check the signal. I transmit a continuous 25 kHz wave for the debugging. When I read the raw input from the receiver (detaching all the circuit that follows the receiver), I see a signal that decreases in steps, and I don't understand why (could also be that the transducer produces a small current that the Arduino analog reader cannot properly read).Furthermore, after filtering it with a Sallen-Key filter (high-pass with cut -off frequency at 20 kHz), I still see a linearly decaying trend in the output while ideally i expect a signal centered in 0 and filtered. Could it be a stability related problem?My question is: do you have any clue why I don't simply receive a 25kHz wave (with some noise, obviously) and why my filter doesn't seem to work?I'd be really grateful for any help!!!
sonoff RM433 Protocol - Page 1
Forum section: electronics / projects

author: rvalente
author_rank: Frequent Contributor
timestamp: October 28, 2022, 12:41:32 pm
content: Hello Mates,I may reuse the RM433 remote as a garage door opener, before spending money to decode the protocol, does anyone knows what it uses?I've found a few teardown pictures but the resolution is to low to read properly. I imagine is a 4 bit learning code (fixed SN, no encrypto) key fob IC (similar to old HT6P20), anyway, does anyone know?https://1technophile.blogspot.com/2019/06/sonoff-rm433-remote-control-with-8.htmlGreetings
deleted - Page 1
Forum section: electronics / projects

author: legacy
author_rank: Super Contributor
timestamp: February 27, 2019, 05:52:36 pm
content: deleted

author: 001
author_rank: Super Contributor
timestamp: March 01, 2019, 07:18:00 am
content: sorrywhat is Your purposes?

author: helius
author_rank: Super Contributor
timestamp: March 01, 2019, 08:49:36 am
content: Where were you able to find the expansions for the RB532? It went out of production over a decade ago.
Sony Betacam SP broadcast camera - microphone type - Page 1
Forum section: electronics / projects

author: shianne
author_rank: Contributor
timestamp: October 08, 2022, 02:14:37 pm
content: Hello,I have a microphone which seems to be from an Sony Betacam SP broadcast camera.I am interested in how the contruction of this microphone works and what is the benefit in comparison to an classical shotgun microphone.From a first view it seems to be a clasic shotgun mic (mic.jpg).Even the directional sensitivity "feels" like a shotgun mic (I did not measure it, only trying it with a recorder).If I look inside, it is not the classical construction.Inside the outer slottet tube is another tube mounted with a shock mount rubber part (front_view.jpg).The inner tube has a slot along one side. One end shows into the direction of the sound source,the other end is directly coupled to the electret capsule. The slot itself is covered with thin felt to prevent wind noise (inner_tube.jpg)The electret capsule is back vented and so it must be a pressure gradient receiver based on the construction.The idea behind seems to be to make the capsule longer and so have a longer travel time for the sound pressure wave from the front side to the back side of the membrane.The slot on the inner tube helps to prevent a sound like an "microphone inside a watering can", which I guess coming from the resonances indise a tube.But why did the designers prefer this instead of a classic shotgun?Is there a special name for this contruction?Best regards,shianne

author: AndyBeez
author_rank: Frequent Contributor
timestamp: October 08, 2022, 02:31:57 pm
content: It's a cardioid microphone design. Which isa type of sensitive uni directional microphone. For broadcast use it records general ambient sound ahead of the camera. However most live sound is recorded on seperate mics plugged into the XLR socket on the back of the cam; including the highly directional shotgun mics maintained by the sound operator.http://www.learningaboutelectronics.com/Articles/What-are-cardioid-microphones

author: shianne
author_rank: Contributor
timestamp: October 09, 2022, 07:56:30 am
content: Thank you for your reply.I find it odd that the design principle doesn't seem to be described anywhere.The classic interference tube design, on the other hand, is described everywhere.If I compare it this design to the classic shotgun mic, the cardioid seems to be the better one if it comes to audio quality from off-position-sounds.Well, I didn't think of the use for ambient sound.I tried the microphone and wondered why they put a mic like that on the camera.My only thought was: You can't film that close, can you?
Sony Bravia KDL-46W4500 46'' TV Issue - Page 1
Forum section: electronics / projects

author: LeWidget
author_rank: Regular Contributor
timestamp: October 02, 2013, 01:27:47 pm
content: Hi guys,New to electronics so hoping for a little feedback from the expertsI have a Sony Bravia KDL-46W4500 46'' TV nothing will appear on the screen. Instead it looks like it just slowly heats up. If I use the remote, I start to get odd lines on the screen too. Here's a short video I made showing the issue.I haven't opened the screen up yet (currently making space) but was hoping I could get some suggestions on what it may be or where to start looking.Regards,

author: madsci
author_rank: Regular Contributor
timestamp: October 03, 2013, 07:02:10 am
content: My first suspects are the timing control board or a loose LVDS cable from the mainboard to the T-con board.Feed it another source and see if the lines change. It may also be a bad mainboard.

author: LeWidget
author_rank: Regular Contributor
timestamp: October 03, 2013, 03:19:27 pm
content: Quote from: madsci on October 03, 2013, 07:02:10 amThanks for the feedbackIll hook up another device & see if anything changes.Regards,
Sony XDR-S3HD Radio Battery Backup - Page 1
Forum section: electronics / projects

author: don.r
author_rank: Frequent Contributor
timestamp: September 23, 2019, 04:06:48 am
content: I recently acquired an HD radio since stations have started appearing in my area. Its a vintage 2007 Sony XDR-S3HD and is a spectacular FM receiver. One of its shortcomings is a lack of battery backup for the presets, configs, etc. so that when the power goes down or I unplug it, I lose everything. I was thinking of re-purposing an 18650 cell to act as a backup. The micro uses a 3.3V line fed by IC902. My plan was to use a diode from the 4.9V rail that feeds IC902 and add a 100ohm current limiting resistor. This should feed the cell a maximum of 4.2V. From there I would add another diode and another 100ohm resistor (just in case!) giving 3.5V and tap into the 3.3V line after D907 on the 3.3V regulator's output. The CPU has a 2.7V to 5.5V input range. Thoughts?
Sony DVD Player thwarted by single dog hair - Page 1
Forum section: electronics / projects

author: Stonent
author_rank: Super Contributor
timestamp: February 22, 2014, 06:56:19 pm
content: My Mom has a Sony DVD player that we got in the 90s that was probably one of the first consumer DVD players on the market.It had all the bells and whistles at the time, Dolby digital and DTS decoding built in, individual 5.1 channel outputs, component out, Svideo out etc.A few weeks ago it just stopped powering on, the standby light was just red all the time and it wouldn't respond to power button presses or remote. I swapped in one of my wife's old DVD players but my Mom didn't really like it because the motor was very noisy and the head movement sounded like scraping and she asked that I please try to fix her DVD player.So I got it and focused on the power supply and at first saw a large transistor with what I thought was a slightly discolored base pin and the plastic looked slightly discolored in one part.I plugged the DVD player in and could hear a faint buzzing from the power supply board. I couldn't exactly trace it down but from previous experience remembered that transformers will buzz if shorted sometimes.I saw a single dog hair (see red line in picture) laying across one of the terminals of the transformer and on top of D105 and L102. And I took a deep breath and blew it out of the way. To my surprise the buzzing stopped and immediately the motor started spinning and the laser started reading the movie that was stuck in side. It was fixed!So a single dog hair took down the whole unit. Amazing.

author: SeanB
author_rank: Super Contributor
timestamp: February 22, 2014, 07:30:28 pm
content: Hair can be quite hygroscopic, and picks up a lot of moisture.

author: Zbig
author_rank: Frequent Contributor
timestamp: February 22, 2014, 10:14:25 pm
content: You blew it (see what I did here?) by giving it away right in the subject line. You should have build the suspense slowly before revealing it. It felt like someone told you that "the dog did it" right when you're waiting in the queue for a movie ticket.

author: kizzap
author_rank: Unknown
timestamp: February 23, 2014, 03:27:57 am
content: Quote from: Zbig on February 22, 2014, 10:14:25 pmSnape klls Dumbledore
Sony KDL-40HX700 Overvoltage Error APS-254 - Page 1
Forum section: electronics / projects

author: Noah
author_rank: Newbie
timestamp: November 10, 2013, 10:11:52 am
content: Hi guys!My Sony LCD TV KDL-40HX700 has broken!If I turn it on, it works fine for about 10 minutes or so but then it goes to standby. The red standby light flashes 7 times and the pauses and then again 7 flash and so on... After a bit of googling i figured out that 7 times flashing is ainternal overvoltage error.I opened the sucker up and checked the caps for shorts but it seems that all are good. The power supply board is theAPS-254.Does anybody ever had the same issue? I couldn't find any service manual or schematics. My next steps would be to check all voltage rails, but before that i wanted to ask, if anybody had the issue before.Thanks!!

author: SeanB
author_rank: Super Contributor
timestamp: November 10, 2013, 11:11:45 am
content: How old is the unit, the CCFL lamps could be at end of life and thus needing higher voltage to light, which trips the overvoltage circuit in the inverter.Check supply voltages from the power supply, and look at the backlight and see which driver they use and find the datasheet and find the overvoltage output and measure that as well.

author: Noah
author_rank: Newbie
timestamp: November 10, 2013, 11:16:54 am
content: Thanks for your reply! The TV is about 4 years old I think this isn't too long now..? I'll now check the voltages for the mainboard and the unregulated 24V for the Backlight. If they are good i have to tear it down a bit more...

author: Noah
author_rank: Newbie
timestamp: November 10, 2013, 12:40:08 pm
content: Okay i checked the voltage rayls and they are all good.There are 3 wires comming from the mainboard to the power supply and forwarded to the backlight board:BL-ONDimmerBL-Errand the BL-Err is constant on 3.3V when i turn it on and then it goes straight into stby so i think the error IS comming from the Backlight board. This is the Board:http://www.shopjimmy.com/samsung-lj97-02541a-backlight-inverter.htmLJ97-02541Aand the controller on it is labeled SSI091ASN i couldn't find a datasheet for it.I think my repair ends here or i buy the replacement...
Sony Lanc Protocol Master/Slave - Page 1
Forum section: electronics / projects

author: DaddyShizzle
author_rank: Newbie
timestamp: October 18, 2024, 01:33:21 pm
content: Hello,I have a problem with the Sony Lanc Protocol. Usually, a camcorder or even a broadcast 4K camera will be the Lanc Master and the Rec/Stop Lanc remote will be a Lanc slave. My problem is that the Atomos Shogun external video recorder acts like a slave, and a standard Lanc remote will not work with it, because it is also a slave. I need to find documentation or get help with writing code for the Master Lanc side of the protocol. There are tons of standard slave Lanc projects online, but nothing about the Master(camera) side of the protocol. I need to make a Lanc remote that acts like a camera(master) so the Atomos Shogun will trigger record.Any help will be much appreciated, thanks.

author: aeg
author_rank: Regular Contributor
timestamp: October 18, 2024, 11:49:06 pm
content: LANC, that's a blast from the past. My recollection is that coincident with every frame of video, the camera sends a LANC frame on the bus, with certain bytes (such as timecode) filled in. Other bytes in the frame, the remote is supposed to "fill in" with its commands during the camera's transmission. Sony had a manual "Protocol of Control L/Lf" (P/N 9-972-453-11 or *PROTOLF), but it is not very illuminating.

author: scottapotamas
author_rank: Regular Contributor
timestamp: October 19, 2024, 03:59:04 am
content: I guess the difficulty depends on your familiarity with working with embedded peripherals and how you're electrically interfacing with the LANC bus from your micro.LANC isn't necessarily per-frame as aeg mentions, the Panasonic cameras I've worked emit their frames on a 10ms interval for example.In the simplest/easiest case while relying on loose timings being OK:Separate RX and TX UART capable IO pins connected to sense and 'drive' circuits should be enoughThe master is responsible for providing the start-bit, so you can just 'send' 8x 0x00 bytes at 9600 baud 8N1 to achieve this without much work.The camera's I've interacted with typically use a slightly longer (than normal UART) stop-bit/gap after each byte of approximately one bit duration, so if the peripheral supports that you should use it, or you might need a timer to coordinate the UART TX for each byte. You'll probably be fine without it though.Keep track of the byte 'index' you're sending and service the UART RX for the first 4 bytes to catch slave commands.You're already sending 0x00 bytes, but for the last 4 bytes you send your status etc. Flush/disable/ignore the UART RX when you're doing this.Remember that you need to send/read some number of repeated sequential frames to consider a command valid (typically 4).
Sony M600i tear down - Page 1
Forum section: electronics / projects

author: ric96
author_rank: Newbie
timestamp: September 18, 2015, 10:45:56 am
content: I very much like David's Style of tearing thing down on the eevblog videos so i decided to do one myself in a similar fashion, of cource its not anywhere near as awesome but i had a lot of fun...thnx