hybridfree/eevblog-posts huggingface dataset:
Eagle blind via drill layer - Page 1
Forum section: electronics / projects

author: itdontgo
author_rank: Regular Contributor
timestamp: October 15, 2016, 05:48:56 pm
content: Hi,Does anyone know what the drill layer for a buried via is in eagle? For example, when going to CAM, how do you add drill holes for route 2-3 to your gerber without ending up with a hole from top to bottom.I hope that makes sense!Thanks

author: Jeroen3
author_rank: Super Contributor
timestamp: October 19, 2016, 09:55:31 am
content: You'll need an additional drill layer. Doesn't it create such layer automatically when you set your board setup?
Eagle cad and sketch up 3d models - Page 1
Forum section: electronics / projects

author: Rickpercy87
author_rank: Contributor
timestamp: February 26, 2016, 05:08:12 pm
content: So I want to play around with the 3d models. Is there anywhere I can download a mass of components in one zip file and drop it into my models folder? Only really looking at simple components for now. A mix of smd and through hole.In addition, I've downloaded a couple of parts but they don't appear to be to scale. They components are generated but they are tiny in comparison to the board.CheersSent from my SM-N9005 using Tapatalk

author: ajb
author_rank: Super Contributor
timestamp: February 26, 2016, 06:45:18 pm
content: Do they have to be sketchup models? 3dcontentcentral.com is a great resource, but it doesn't look like sketchup files are an option. Many other CAD formats (including STEP, which is pretty common) are available, so maybe something will work. tracepartsonline.net is another good resource, a number of manufacturers make their CAD models available there. Just be aware that a lot of the models on both sites are user-provided, so for things where dimensions really matter (IE, connectors that will need to match up to a housing) it's worth verifying their accuracy yourself. Actually, for that matter, I've found discrepancies in manufacturer-provided models, so. . .verify any critical dimensions, really.

author: Rickpercy87
author_rank: Contributor
timestamp: February 26, 2016, 08:54:03 pm
content: In it sure if the have to be sketch up models. I'll have a look at the file extension and if there is any converter if there is.I'm just looking for a simple zip file containing. Resistors, capacitors transistors etc of most packages.Does anyone know why the 3d components are not placed on the board correctly? And why they are relatively tiny compared to the PCB?Sent from my SM-N9005 using Tapatalk

author: ajb
author_rank: Super Contributor
timestamp: February 26, 2016, 10:24:00 pm
content: I don't know much about sketchup, is it possible that the parts were created in inches but imported in millimeters?

author: Rickpercy87
author_rank: Contributor
timestamp: February 27, 2016, 03:19:24 pm
content: That sounds like it could be the problem. I didn't know how to create the correct template size. I'll have a look at this tonightSent from my SM-N9005 using Tapatalk

author: Josephine85
author_rank: Contributor
timestamp: March 29, 2016, 12:57:36 pm
content: Couldnßt find anything in the manual or FAQ, maybe you should consult the support:Technical Support: support@cadsoftusa.comSales/ License Management: sales@cadsoftusa.comPhone: +1 954-237-0932http://www.cadsoftusa.com/
Eagle CAD print pdf generation issue - Page 1
Forum section: electronics / projects

author: Dhanushka
author_rank: Regular Contributor
timestamp: June 25, 2019, 03:01:28 pm
content: When I generate a pdf file in Eagle, the output is a colored image like i have attached. Please anyone can tell me that how generate a pdf file with black traces on white background for toner transfer method. Only I need to go through pdf print way.Thank You

author: Dhanushka
author_rank: Regular Contributor
timestamp: June 26, 2019, 04:54:37 am
content: However, I solved this problem. There is a check box to select the black color in the print options.
Eagle Newbee - Page 1
Forum section: electronics / projects

author: danadak
author_rank: Super Contributor
timestamp: June 28, 2016, 08:35:41 pm
content: I have a schematic and have some issues -1) After doing ERC and clearing up several errors there remains 2 errors, "only one pin on net".I did everything from move/rubber band to see connections made, to deleting and redrawing.Cannot get rid of the two warning errors.2) Just having warnings I try to trial autoroute, get this "The light edition of eagle cant perform the requested action".Trolling the net seems like light edition does contain autorouting feature, so not sure whats going on.Any help greatly appreciated.Regards, Dana.

author: MagicSmoker
author_rank: Super Contributor
timestamp: June 28, 2016, 09:06:58 pm
content: I can't help you with autoroute, but looking at your schematic you've made a common mistake with your drafting: there should not be connection dots on components.The specific ERC issue you are having is the diode in between IC1a and R1 is not a completely characterized "device". That means that the library entry has a symbol - what is shown on the schematic - and one or more packages - shown on the PCB. A "device" in EAGLE is a library entity that associates the pins on a symbol to pins on one or more packages.So fix your diode library device and that should solve the ERC problem.

author: Josephine85
author_rank: Contributor
timestamp: June 30, 2016, 09:04:15 am
content: If you still have some issues, you can contact the free support:http://www.cadsoftusa.com/training-service/support/Regrads

author: con-f-use
author_rank: Unknown
timestamp: July 01, 2016, 09:41:08 am
content: UseKiCadits free and better than eagle... I know this is controversial but now that you haven't invested much time, use KiCad!

author: FreddyVictor
author_rank: Regular Contributor
timestamp: July 01, 2016, 03:14:48 pm
content: Quote from: danadak on June 28, 2016, 08:35:41 pmOK, Eagle is OK, but does have some quirks ...appears D1 is not actually connected - seems there is something wrong with that part (maybe its pins are slightly out ?)If you pick it up & move it, the net wires don't follow, so try using a different diodeThe message mentioned net N$15, so I just did cmd in the line above the schematic: 'show n$15' to highlight where the error wasps: you only need to use the junction marker where net (wires) cross and need to be joined rather than on each pin
Eagle PCB Labeling Traces - Page 1
Forum section: electronics / projects

author: SethGI
author_rank: Regular Contributor
timestamp: January 31, 2017, 02:45:26 am
content: Hi,I just updated to the latest version of Eagle. All of a sudden it's doing this weird thing and labeling all my traces. I've never seen this, and can't figure out how to turn it off without deleting each label in the schematic. Any advice?Thanks,Seth

author: H.O
author_rank: Frequent Contributor
timestamp: January 31, 2017, 06:29:06 am
content: (Wrong forum section)It's a highly requested feature that users have been waiting for for years...I suspect there's a setting somewhere to turn them on/off but I don't have EAGLE available at the moment. If you don't want to see them, just turn off the layer which they're on (guessing on 104).

author: KE5FX
author_rank: Super Contributor
timestamp: January 31, 2017, 06:41:21 am
content: It would have been a useful feature, too, if they had limited it to user-assigned names.Who wants to see a forest of "N$xxx" labels?Here's how to turn it off on the Options->Set->Misc page:
Eagle PCB Layout question - Page 1
Forum section: electronics / projects

author: MCPorche
author_rank: Contributor
timestamp: January 07, 2015, 07:34:49 pm
content: I'm pretty new to Eagle, and I would like to lay out some LEDs in the shape of a logo.Is there a way to import an image into Eagle and use it as a template for placing parts?

author: Wilksey
author_rank: Super Contributor
timestamp: January 08, 2015, 12:18:34 am
content: There is a BMP import script / ULP within Eagle, the Cadsoft website might have an other format importer. Just change the layer to Drawing and add your parts.

author: MCPorche
author_rank: Contributor
timestamp: January 08, 2015, 03:49:43 am
content: Thanks so much, I'll give that a try.
Eagle PCB - Page 1
Forum section: electronics / projects

author: crusader66
author_rank: Contributor
timestamp: January 23, 2011, 04:59:26 am
content: Hey all. I've recently been attempting to use Eagle PCB. Anyone happen to use this software? If so, do you have a library for a MC68HC16Z1CEH25 or something that comes in same package? If I could just get the package, I'd be happy as hell. Nothing I hate worse than drawing the package.

author: OhmEye
author_rank: Contributor
timestamp: January 23, 2011, 05:40:03 am
content: If you have the 144 TQFP pin package, perhaps one of the footprints in the lattice library will work, or at least make it easier to create one. I don't see any 132 pin PQFP packages at all in a search of my libraries, so sorry, no I don't seem to have a library for it either.Best of luck to you! I hope somebody else here can help

author: tyblu
author_rank: Frequent Contributor
timestamp: January 23, 2011, 06:08:56 am
content: You have to make your own parts in every design you make. Stock libraries are sparse, restrict you to old parts, and may have the wrong or outdated footprints.

author: crusader66
author_rank: Contributor
timestamp: January 23, 2011, 07:10:36 pm
content: I usually draw my own symbols and packages but thought I might try to cheat a little on this one. Thanks to OhmEye and tyblu for responding. It was worth a shot.

author: Chasm
author_rank: Regular Contributor
timestamp: January 23, 2011, 09:40:26 pm
content: Take a look at the ref-packages.lbr and ref-packages-longpad.lbr libraries.

author: crusader66
author_rank: Contributor
timestamp: January 25, 2011, 03:19:08 am
content: This is one of those moments where I realize that many times along the way and always after the project is finished, I feel more stupid than when it started."Why didn't I see that?" is rapidly becoming the phrase I repeat the most.Thanks, Chasm.

author: zijo
author_rank: Newbie
timestamp: January 27, 2011, 01:05:37 am
content: I useAutoTRAX EDAhttp://www.kov.com/Cheap (up to 200 pins is free) easy to use, make components, 3d view, prepare for manufacturing…etc.
Eagle power trace on 2 layers with vias - Page 1
Forum section: electronics / projects

author: cosminnci
author_rank: Regular Contributor
timestamp: October 30, 2013, 05:57:06 am
content: I am making a pcb which needs more trace width and want to place the power traces on both layers overlapping and vias connecting the 2 from place to place.1 layer routing works ok but for the 2 nd layer eagle won`t allow routing the same trace only if I disconnect from the schematic and put wire.is there a workaround for this?

author: Kjelt
author_rank: Super Contributor
timestamp: October 30, 2013, 07:50:10 am
content: I am a hobbyist so perhaps some more professional can help you better but what i usually do:You can manually place a "wire" on the pcb wherever you want on which layer you want, you just have to "name" it the same labelname as the power trace and then you can manually place as many via's as you want. But it is totally seperated from the normal "route" way of doing.

author: cosminnci
author_rank: Regular Contributor
timestamp: October 30, 2013, 09:11:10 am
content: This works but when placing a wire it says can`t backannotate this operation. please do this on the schematic.if I close the schematic it severs the connection and I can`t add any other parts/traces.

author: Kjelt
author_rank: Super Contributor
timestamp: October 30, 2013, 10:02:38 am
content: But there is nothing to backannotate because you don't alter the schematic, you alter the pcb design, if you rename the wire to the powerlabel it should all be fine. If you place a wire eagle gives it a new netname but that should be altered by you to the exact same name as the trace on the other side.

author: Kremmen
author_rank: Super Contributor
timestamp: October 30, 2013, 12:27:22 pm
content: You may have missed it but there is a separate area for Eagle. Maybe you should take this where it rightly belongs?

author: kizzap
author_rank: Unknown
timestamp: October 30, 2013, 12:53:27 pm
content: If I need to do something like this, I usually just rip-up a trace near where I want to connect to, and run the second trace, then reconnect the ripped up trace.Then just hit vias on the trace as needed. No need to name them if you place them on the centre of the trace.-kizzap

author: cosminnci
author_rank: Regular Contributor
timestamp: October 31, 2013, 06:40:58 am
content: @Kjelt it works and it is simple enough.thank you.Cosmin
EAGLE - preventing vias from connecting to a layer - Page 1
Forum section: electronics / projects

author: tree
author_rank: Regular Contributor
timestamp: June 11, 2014, 10:13:50 pm
content: I am working on a 6 layer board and here is the layer stack up:AnalogGround (plane)Dig/PowDig/PowGround (plane)AnalogOne ground will be used for shielding while the other will be used for return currents. They both will be connected in a star ground fashion at the power supply. The problem if you can't see yet is the possibility of ground loops. If I place a via from a bypass capacitor to ground (return) the via will connect to both grounds and create a ground loop. How do I place vias such that they will only make electrical contact with only one ground layer?Thanks.

author: theatrus
author_rank: Frequent Contributor
timestamp: June 11, 2014, 10:17:02 pm
content: Without having each ground be a unique net, or using blind vias, this doesn't sound possible in Eagle.

author: tree
author_rank: Regular Contributor
timestamp: June 11, 2014, 10:27:47 pm
content: Quote from: theatrus on June 11, 2014, 10:17:02 pmThat's what I was afraid of. Looks like I'll have to use a 0-ohm resistor for renaming the net!

author: Lunasix
author_rank: Regular Contributor
timestamp: June 12, 2014, 08:11:42 am
content: It's possible to create a special component with 2 pads with a net (in library) between them. You will have a warning in the drc, but you can ignore it. So, no need to solder a 0 ohm resistor. There is possibly a better idea...

author: larry42
author_rank: Regular Contributor
timestamp: June 12, 2014, 08:42:12 am
content: Quote from: tree on June 11, 2014, 10:13:50 pmAlthough I've run into problems with multiple ground planes before - none of those problems were due to capacitors connecting grounds together. The stackup you show *requires* good ground coupling (if the grounds are poorly coupled - what happens to the return currents of the digital tracks)?

author: zapta
author_rank: Super Contributor
timestamp: June 12, 2014, 02:09:46 pm
content: Quote from: Lunasix on June 12, 2014, 08:11:42 amA nc solder jumper is one example.
Earphone repair - Page 1
Forum section: electronics / projects

author: Vintage1873
author_rank: Newbie
timestamp: October 17, 2016, 11:37:14 pm
content: Hello Everyone

author: Vintage1873
author_rank: Newbie
timestamp: October 17, 2016, 11:40:04 pm
content: I just realized I posted this in the wrong section. My apologies, could a moderator please move this to the repair board? Thank you!
Earth Bond Check Box - Page 1
Forum section: electronics / projects

author: mendip_discovery
author_rank: Super Contributor
timestamp: December 11, 2023, 07:48:04 pm
content: I was at a customer's place today and I have failed a few Seward HAL104 Flash Testers as the Earth Bond has gone wrong.The issue the customer has is when the earth bond part of the tester breaks it means that it could pass stuff that is actually a fail. Which isn't great.What I am thinking is a Box with either the wires or a mains plug on the end, they make lighting so most of use a break out thing that accepts the wires. Then a Zero, 0.1 Ω, 0.5 Ω and 1 Ω resistor for checking Earth Bond.I am guessing some nice chassis mount resistors are capable of putting up with 10A at 6V AC (Spec Sheet says 6V AC) so let us say 100W just to give some space for error. Now would it be best to connect 2 in a parallel configuration to help keep the heat down but also to help keep the ppm/C from impacting the readings?Also, I wondered about adding a 200 kΩ resistor to the neutral > earth (with a jumper lead) so that they can check the leakage current at 1 kV which should be 5 mA. Swappable to a 10 MΩ and 100 MΩ for testing DC Insulation. But I am not sure what resistors to look for.All this so they can do some sanity checks with the QC department from time to time. I was thinking of making one for myself as a backup for the bit of kit I already have. Seward does sell a Y160 Fault simulator with just a few fixed points at £130 last time I checked (https://www.seaward.com/gb/products/manufacturing/accessories/fault-simulators/y160h-fault-simulator/)
Earth line inductor? - Page 1
Forum section: electronics / projects

author: oxcart
author_rank: Contributor
timestamp: August 10, 2015, 11:29:12 am
content: Still playing with EMC/EMI filters, and I've noticed that some have an "Earth line choke", ashttp://schaffner.com/en/products/datasheet-low-res/product/fn-9244e-excellent-performance-iec-inlet-filter-with-earth-line-choke.pdf.The supposed benefit is more attenuation of noise passing in the ground line, but are there safety issues?

author: SeanB
author_rank: Super Contributor
timestamp: August 10, 2015, 12:08:35 pm
content: No, the earth line choke is rated to fail after the line leads have blown apart from overload. The line choke wiring will survive 15A and the earth line will do the same. The wiring is the same size as the line side, it just provides lower common mode leakage out via the cable.
Easiest method to connect pcb to a lcd module with a single row style connection - Page 1
Forum section: electronics / projects

author: alank2
author_rank: Super Contributor
timestamp: August 19, 2014, 05:26:24 pm
content: I've been using LCD's that have a 2x8 header on them with a 2x8 female header on my pcb, but I may have to redesign and the price of the 16x2 or 40x2 lcd modules on eBay are a bit attractive except that they don't have the 2x8 configuration, but the 1x16 configuration. I only run 4 bit mode so four of the wires can be left out, so instead of 1x16 it could be a 1x6 (pins 1-6) and a 1x6 (pins 11-16).What ideas do you guys have for the easiest (least work) and cheapest connection between a module and pcb given 2 situations:1-module is stacked over pcb.2-module is not stacked over pcb.I was looking at some 6 conductor 0.1" ribbon cable over at digikey, but it wasn't cheap and also how would you strip the end of it consistently?I thought about some male header on the pcb and just mounting the lcd on top of that which would be easy, but be a permanent connection...Thanks,Alan

author: bobcat
author_rank: Regular Contributor
timestamp: August 19, 2014, 05:49:52 pm
content: You can get 2 row breakaway headers, and make them 8 positions wide. IDC connectors for flat cable are easy to use, just carefully squeeze them shut over the wire.

author: sacherjj
author_rank: Frequent Contributor
timestamp: August 19, 2014, 06:00:28 pm
content: Get an old IDE cable. Cut, strip and solder it in place. These things are pretty much free now. You can double up connectors if the pitch is too fine.

author: gxti
author_rank: Frequent Contributor
timestamp: August 19, 2014, 06:11:55 pm
content: I used a 1x16 breakaway header socket on the PCB, along with 1x16 header pins on the LCD module. Not the cheapest solution but it was for a one-off project where being able to remove the LCD to poke at the PCB underneath was important.

author: mariush
author_rank: Super Contributor
timestamp: August 19, 2014, 06:15:16 pm
content: I've bought 1x5 and 2x5 plastic headers, they're very cheap. The actual metal contacts are also cheap (2$ for 100 pins or something like that).The crimping tool is a bit more expensive at about 20-30$ but it's a one time purchase. Worth it.

author: sacherjj
author_rank: Frequent Contributor
timestamp: August 26, 2014, 08:23:07 pm
content: Quote from: mariush on August 19, 2014, 06:15:16 pmAnd if you are too cheap for the tool, I've used two small pieces of metal and a C-clamp. But I have a cheap tool now and it was totally worth the $20.
Easiest way to add WPA2 Entreprise support ?? - Page 1
Forum section: electronics / projects

author: jemangedeslolos
author_rank: Frequent Contributor
timestamp: May 01, 2020, 03:39:55 pm
content: Hello,I have a custom board with sensors that transmit datas to online IoT plateform (Thingspeak ) with onboard wifi ( ESP8266 + AT commands ).All is working great...except that now I need to connect my board to a Wifi that only accepts WPA2 enterprise authentication.Does anyone have experience using wifi module who supports WPA2 Entreprise authentification ? ( ESP8266 if possible)In the ESP8266 AT Instruction Set PDF, it is clearly indicated that AT can NOT connect to WPA2 Enterprise AP.Thank you for your help

author: nuclearcat
author_rank: Unknown
timestamp: May 06, 2020, 09:54:14 am
content: ESP8266 RTOS SDK does support WPA2 enterprise, but i guess you need to write firmware to have necessary functionality, or hire someone.Here is example:https://github.com/espressif/ESP8266_RTOS_SDK/blob/8456b7450e06c67d434323c5b41185f878c8945f/examples/wifi/wpa2_enterprise/main/wpa2_enterprise_main.c
Easiest way to connect the BOOTSEL test metal terminal and the GND terminal.... - Page 1
Forum section: electronics / projects

author: ziomario
author_rank: Contributor
timestamp: April 06, 2025, 07:10:23 pm
content: Hello.What I want to do is to ask to a pcb maker to create the BBQ20_USB_Keyboard for me (because it is sold out,but I need this nice keyboard for building my DIY phone)The BBQ20_USB_Keyboard comes equipped with a blank RP2040 with nothing written to it.I will need to write firmware to it.It's not difficult, though. The Raspberry Pi Pico RP2040 uses an excellent and simple method for writing firmware.When I connect it to your PC via USB while holding down the BOOTSEL button, it will be recognised as a USB memory stick. All I have to do is place this file there.However, there is a major challenge for me.The BBQ20_USB_Keyboard board does not have a BOOTSEL button...https://ibb.co/HLSgL3RhWith a regular Raspberry Pi Pico, I simply press this button...https://ibb.co/nN5J3dc7With the BBQ20_USB_Keyboard l need to connect those two round metal terminals on the back of the board. But ZitaoTech (the creator of the keyboard) didn't include that button.I would like to know if I can use a tool like this one :https://www.sparkfun.com/alligator-clip.htmlto electrically connect the BOOTSEL test metal terminal and the GND terminal while I connect the USB memory stick.Thanks.

author: negativ3
author_rank: Regular Contributor
timestamp: April 07, 2025, 10:01:30 pm
content: "to electrically connect the BOOTSEL test metal terminal and the GND terminal while I connect the USB memory stick."You mean plug it into your PC, right?Switch side 1 > GND > Diode Anode, Cathode > Bootsel > Switch side 2.Shorts GND to bootsel for as long as you need to enter UF2.1N4148 diode is a jellybean good for this.A momentary switch, it's the only way I can see of doing it.I asked this very question in another thread.

author: ziomario
author_rank: Contributor
timestamp: April 07, 2025, 10:06:30 pm
content: The usage of that diod requires the usage of a welder ?

author: negativ3
author_rank: Regular Contributor
timestamp: April 07, 2025, 10:10:30 pm
content: A soldering iron.

author: ziomario
author_rank: Contributor
timestamp: April 07, 2025, 10:32:56 pm
content: I can't. I would like to avoid any kind of soldering. Why the alligator clip does not work ?

author: moffy
author_rank: Super Contributor
timestamp: April 07, 2025, 10:39:40 pm
content: Quote from: ziomario on April 07, 2025, 10:32:56 pmAligator clip is probably too large to work.

author: ziomario
author_rank: Contributor
timestamp: April 07, 2025, 10:41:10 pm
content: Nice hint. At least now I know that a narrower one could work...if it exists.

author: moffy
author_rank: Super Contributor
timestamp: April 07, 2025, 11:13:12 pm
content: Perhaps something more like this, but I can't be sure:https://www.adafruit.com/product/4322

author: ziomario
author_rank: Contributor
timestamp: April 07, 2025, 11:17:41 pm
content: So nice !
Easiest way to convert oscilloscopoe waveform to binary data table - Page 1
Forum section: electronics / projects

author: DaveHardy
author_rank: Regular Contributor
timestamp: February 12, 2013, 05:53:41 pm
content: I'm interested in capturing a waveform on an oscilloscope, normalizing it, and then down sampling one period of the waveform into roughly one thousand samples. Any ideas? I'm sure that there are some fancy oscilloscopes out there that can do this but I've never used one. Is there software somewhere that can do this?I found a website that created a sine wave for me here but I want other common mathematical waveforms:http://www.daycounter.com/Calculators/Sine-Generator-Calculator.phtml

author: DaveHardy
author_rank: Regular Contributor
timestamp: February 12, 2013, 06:58:16 pm
content: Matlab?

author: Smokey
author_rank: Super Contributor
timestamp: February 12, 2013, 09:01:22 pm
content: Python?

author: Nirios
author_rank: Regular Contributor
timestamp: February 12, 2013, 09:11:45 pm
content: +1 for Python. Also look into the python libraries: NumPy and SciPy; matplotlib for visual graphing.

author: Unknown
author_rank: Unknown
timestamp: February 12, 2013, 11:27:54 pm
content: Export the signal from your scope as CSV. You can import this CSV in almost any mathematics package (eg. MATLAB) or programming language (eg. Python). The learning curve for both will be quite steep if you've never used them before. If you're into NI products, you could probably do this in SignalExpress. Including capturing it from the scope and down sampling. You could even import it into the abomination called Excel.You could skip samples or do some averaging to sample it down to the desired sampling rate. Fancier algorithms might first reconstruct the signal and resample this reconstructed signal. It depends on the ratio between original sampling rate and desired sampling rate, and the desired fidelity.

author: DaveHardy
author_rank: Regular Contributor
timestamp: February 13, 2013, 12:22:30 am
content: Hey thanks guys. Python looks really tough. Do all digital scopes have CSV output capability?

author: DaveHardy
author_rank: Regular Contributor
timestamp: February 13, 2013, 12:35:02 am
content: NI Labview looks the most promising. How long do you think that it would take me to learn it? I'm a complete novice.If I give detailed instructions, would anybody be interested in processing the data that I provided them from a simple scope like a Rigol 1052?
Easiest way to create 1A constant current, for 4 lead ohm memsurement - Page 1
Forum section: electronics / projects

author: jase_31
author_rank: Newbie
timestamp: September 11, 2020, 09:45:39 pm
content: What is the easiest way to get a 1A constant current (using a battery) so i can measure the resistance of a long length of cable using a 4 lead method and my existing multimeter.I need to put 1 1A constant current (like a bench supply) - but fed from a battery (18560) or USB battery packI have seen Youtube videos that provide it with a LM314 and a resister. There are a number of power modules on ebay (usually based on the LM2577Can I use something like a Step-down-Power-Supply-Module-5-32V board, that is designed to as a charging circuit.https://www.ebay.co.uk/itm/DC-DC-CC-CV-Lithium-Converter-Step-down-Power-Supply-Module-5-32V-to-0-8-30/353167381042?hash=item523a6a9232:g:GOIAAOSwK2hfMlPS

author: bob91343
author_rank: Super Contributor
timestamp: September 11, 2020, 09:48:44 pm
content: To measure resistance, a constant current source needs to be stable and accurate. I don't think there is an easy or cheap way to do that.Why do you want to reinvent the wheel? There are many 4 wire Ohmmeters available, some at very low cost.Alternatively, you can pour some current through and use the voltmeter-ammeter method to determine resistance.

author: Gyro
author_rank: Super Contributor
timestamp: September 11, 2020, 10:00:42 pm
content: Welcome to the forum.This Maxim battery operated App note circuit works well and has very long battery life (as long as you don't hold the button down more than is necessary to make the measurements). You can, of course, substitute the reference and opamp of your choice. It can be as accurate as your choice of reference and resistors.http://www.wentztech.com/radio/resources/Projects/AN106.pdf

author: ledtester
author_rank: Super Contributor
timestamp: September 11, 2020, 11:29:52 pm
content: This is a good video of what considerations go into the design of a milliohm meter:https://youtu.be/anE0jDeBuxo

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 12, 2020, 12:55:53 am
content: Make a sufficiently accurate constant current load and you basically have your answer.
Easiest way to read if low voltage AC on line using microcontroller? - Page 1
Forum section: electronics / projects

author: cbc02009
author_rank: Regular Contributor
timestamp: March 09, 2021, 09:32:01 pm
content: I'd like to use an MCU to detect if a home thermostat is calling for the heat to turn on in order to integrate my dumb thermostats with my home automation system. In the US thermostats essentially just close a 24V AC loop to turn on heat and open it back up to disable it. I mostly write firmware now, so I'm really out of practice with the analog stuff and I was hoping for some input/guidance.basically I want true if AC signal detected on wire, false if not. Don't need to do any measurement or anything.I *think* I can just use a bridge rectifier and then maybe a voltage dropper (or maybe a buck converter? Could be more efficient) to drop it down to ~3V to read in to an MCU. But then what would I reference the signal to in order to keep it from floating?Maybe a sense resistor into an ADC would work better? That wouldn't need to be referenced at all, and if I chose the value for the sense resistor correctly I could keep it within the limits for the ADC. There's not much current on these lines though (20 mA or so) so I worry about dropping the voltage by so much that it no longer triggers the thermostat to turn on.Any thoughts?

author: mariush
author_rank: Super Contributor
timestamp: March 09, 2021, 09:45:15 pm
content: Maybe an optocoupler ?rectify AC with a diode and maybe add a tiny capacitor , add a resistor to limit current going through optocoupler and you can then just read the other side of the optocoupler with your micro.

author: nightfire
author_rank: Frequent Contributor
timestamp: March 09, 2021, 09:45:32 pm
content: How much of a voltage drop is ok for that circuit?Usage of a coupling relay with 24V AC coil voltage is also an option, so that the circuits are isolated against each other.

author: ajb
author_rank: Super Contributor
timestamp: March 09, 2021, 10:48:34 pm
content: Just put an optocoupler with a suitable resistor across the two lines, either an AC input opto (which has two LEDs in antiparallel) or put an external diode antiparallel with the LED to protect it from excessive reverse voltage. That's all you really need. Ideally you'd have a TVS in the mix to protect the opto from transients but it's probably something you can skip for a hobby project. You don't particularly need the opto to turn on for much of the cycle, just enough for the MCU to detect it on each cycle or half cycle.
easy 'Noise' Differential scope measurements - 1996 WK/Farnell PDD3010  manual. - Page 1
Forum section: electronics / projects

author: Freelander
author_rank: Regular Contributor
timestamp: November 06, 2017, 09:22:17 pm
content: I love the old stuff. My WK Instruments / Farnell PDD3010 Bench Lab PSU has a nice little section in the service manual regarding output noise measurement using a differential scope approach without any fancy equipment.Just thought I would share it and would appreciate any observations / comments. I always liked this PSU as well, one of early switching supplies (it still has a linear section for ancillaries) Dual 30V up to 10A. Nice unit. Wayne Kerr / Farnell.Makes interesting reading and I like the approach to differential measurement without spending a fortune.

author: macboy
author_rank: Super Contributor
timestamp: November 07, 2017, 03:54:10 pm
content: This is my favorite and most used bench supply. I have been desperately searching for the PDD3010 service manual for ages. Would you be so kind as to share it with me? I'll send you a PM.This measurement technique can work well for anything with low output impedance. It loads the DUT with 50 ohms per side. You can do something similar with two identical and well matched probes. That will have the benefit of less loading (e.g. 10 M // 10 pF or so) but also attenuates the signal by 20 dB (1/10). That can be a big deal when you are looking at mV level noise.

author: Freelander
author_rank: Regular Contributor
timestamp: November 07, 2017, 04:16:34 pm
content: Quote from: macboy on November 07, 2017, 03:54:10 pmAgreed, a lovely piece of kitService manual and full schematics etc sent. ! - enjoy.I also searched everywhere for the service manual for this and found people selling it for ridiculous prices. The original manufacturer (and I believe designers) were 'Wayne Kerr' using Farnell branding.WKmake some of the most amazing test gear around. I emailed them and got an immediate response with the complete service manual / schematics and data attached (completely free of charge). Even had the name of one of the original designers copied in !!. You won't find many companies offering THAT kind of service these days. (unfortunately)A veritable 'doll' of a piece of kit. I love it.Joe

author: Freelander
author_rank: Regular Contributor
timestamp: November 07, 2017, 04:47:17 pm
content: I have also added the Zipped service manual here for anyone else who may need it now or in the future. Anybody that can find one of these lovely Power Supplies at the right price should grab it.-Farnell / WK / Wayne Kerr PDD3010 PDD3010A Full Service Manual and Schematics(Had to upload in 2 parts due to size limit)Remove the .doc from the pdd3010a Manual.z01 and then run PDD3010A Manual.zip
Easy charging of 2 cell lipo? - Page 1
Forum section: electronics / projects

author: smackaay
author_rank: Regular Contributor
timestamp: April 25, 2013, 08:14:55 pm
content: I have a project that I'm working on and even though the project is finished the customer wants a charging port instead removing the batteries and charging them externally. I'm running 2 18650 lithium ion batteries and while I see lots of solutions for a single cell, I don't see much in the way for 2 cell charging. I was thinking that I could try using two single cell charging IC's but I have no idea how they're going to behave if I split the ground between the batteries, has anyone done this?I've never used charging IC's so I have no idea what to expect. Any help would be greatly appreciated.

author: richcj10
author_rank: Unknown
timestamp: April 25, 2013, 08:23:07 pm
content: Works really well:http://www.digikey.com/product-detail/en/MCP73213-A6SI%2FMF/MCP73213-A6SI%2FMF-ND/2125537I don't remember what cells I actually used this on but they where LG 26650 Li-Ion's and it did a good job.I would make sure your cells are at the same voltage prior to installing into product. The cells should stay nicely balanced.

author: smackaay
author_rank: Regular Contributor
timestamp: April 25, 2013, 08:48:16 pm
content: Wow, that's perfect, thanks!

author: Donziboy2
author_rank: Contributor
timestamp: April 30, 2013, 10:49:34 am
content: I dont see any balancing on that IC at all?

author: richcj10
author_rank: Unknown
timestamp: May 02, 2013, 08:22:59 am
content: Your right, there is none. hence:Quote from: richcj10 on April 25, 2013, 08:23:07 pmThe cells when discharged at a low rate would require no balancing.

author: Unknown
author_rank: Unknown
timestamp: May 02, 2013, 09:43:32 pm
content: Lipo lithium ion batteries, are they that safe ! from what I have seen; or is the media hype causing concern.

author: richcj10
author_rank: Unknown
timestamp: May 03, 2013, 12:27:32 am
content: It depends on how you use it. If you use it in a combat bot, then yes, you will need to balance. The current draw is so great that you need to make sure the cells are at the same potential or boom. I did how ever make a 24v pack with A123 cells and never balanced them and they where fine in a 120lb combat. If you have the cells close to each other and will not be pulling less then let's say 500mA then I can't say that it would be a problem. I know someone from NASA that knows about battery's and I will talk to him.
easy job for all - Page 1
Forum section: electronics / projects

author: damzam12
author_rank: Newbie
timestamp: January 01, 2025, 02:15:02 pm
content: Admin Edit: Video removed, user is just spamming the video to drive up views.referring to this video id like 1k or 5k or these circuit's made and combined to power a usbc pd board with all or the protection features and a battery connected. how much would this be?and how much energy can we expect to get from this configuration.?

author: inse
author_rank: Super Contributor
timestamp: January 01, 2025, 02:31:50 pm
content: uW unless you place it close to a powerful transmitter.Do a rough estimation on how long it took to charge the electrolytic capacitors.Edit: I calculated 25uW

author: SteveThackery
author_rank: Super Contributor
timestamp: January 01, 2025, 03:02:25 pm
content: Can anyone explain step-by-step how that circuit works? I'm having trouble getting my head around it.

author: janoc
author_rank: Super Contributor
timestamp: January 01, 2025, 03:42:13 pm
content: Quote from: SteveThackery on January 01, 2025, 03:02:25 pmWhat is there to explain? It is a bog standard bridge rectifier with an antenna capacitively coupled into it. Diodes rectify the RF from the antenna and charge the capacitors. That's all there is to it. But unless you are sitting right next to a powerful transmitting antenna you won't get anything at all from it because the RF voltage from the antenna will not reach even the forward voltage of the diodes, despite using germanium ones.Youtube is full of junk projects like this.

author: damzam12
author_rank: Newbie
timestamp: January 01, 2025, 04:02:02 pm
content: i wanted to make 5k of them and combine them

author: damzam12
author_rank: Newbie
timestamp: January 01, 2025, 04:06:15 pm
content: im very close.

author: damzam12
author_rank: Newbie
timestamp: January 01, 2025, 04:11:34 pm
content: 25 in how long

author: inse
author_rank: Super Contributor
timestamp: January 01, 2025, 04:18:33 pm
content: Maybe

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: January 01, 2025, 04:25:06 pm
content: Do they still make back diodes?

author: bson
author_rank: Unknown
timestamp: January 01, 2025, 09:12:25 pm
content: You probably get more power from a toy solar panel in moonlight...

author: Whales
author_rank: Super Contributor
timestamp: January 01, 2025, 10:30:14 pm
content: Quote from: SteveThackery on January 01, 2025, 03:02:25 pmThe easy bit are the diodes and the capacitors on the right. The diodes are a bridge rectifier (converts AC from the radio signals into DC) and the capacitors store this DC.The left side, with the two capacitors and the antenna, is quite more complex. Technically it's wrong too (they only show half the antenna, unless you're supposed to connect the negative output to earth?). The capacitors might be acting as some sort of 2x boost when combined with the diodes; or they might be for impedance matching the antenna to the circuit (complex topic), or both.
Using a cheap ebay shell for a 1-20v DC bench power supply. - Page 1
Forum section: electronics / projects

author: kallisti5
author_rank: Contributor
timestamp: October 28, 2014, 08:39:48 pm
content: I've been using a home-built switched mode power supply for a while now, but I really want to move to one with an isolation transformer to help guard against me doing something stupid with my oscilloscope :-) (the 24v switching power supply I used references earth to ground... so I let it unsafely float or attach ground.. eh)I got a el-cheepo lab power supply off of ebay (http://www.ebay.com/itm/331342398526?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)I don't trust it for my daily driver given the price point, but thinking I could replace the transformer as it looks like a simple lm338 design.I may even be able to get 4-5 amps out of it if I redo the electronics.Fuse, transformer, fuse, rectify, caps, LM338 current, LM338 voltage, small caps what could go wrong?Thoughts? Am i throwing money away using the el-cheapo PS-1501s as a base / shell?EDIT:Only thing that sucks is the lack of a earth ground binding post.Scratch that.. there are 3 binding posts there that could be replaced with something higher quality.

author: void_error
author_rank: Frequent Contributor
timestamp: October 28, 2014, 11:45:27 pm
content: If I remember correctly there's a review+teardown of one of those cheap PSUs on youtube. They kinda suck.EDIT: Found it:

author: Macbeth
author_rank: Super Contributor
timestamp: October 29, 2014, 12:17:32 am
content: There is quite a glut of amazingly fantastic HP/Agilent 2 quadrant power supplies on the market since Nokia closed their factories, real cheap. These are ideal for 20V 5A and can act as a perfect linear PSU and a load as well, something other PSU's don't do. Do a search for HP6632A or HP6632B. Dave scored a pile of the 'A' model recently, they seem to go for around £85 each. The 'B' model has RS232 and is still sold by Farnell new for around £2400 inc VAT. You can get an ex-Nokia one for not much more than £100.Only a fool would buy a crappy chinese 20V SMPS for near the same price!.However, these are serious beasts, they weigh around 12kg each. Not portable!

author: kallisti5
author_rank: Contributor
timestamp: October 29, 2014, 01:33:17 am
content: Quote from: Macbeth on October 29, 2014, 12:17:32 amHeh. That is my issue. Small work bench, no room for a monster vintage lab supply. Anyway, also looking for a new project I can work on for 15 minutes at a time with a new baby in the house :-)
Easy stepper motor driver - Page 1
Forum section: electronics / projects

author: Isad
author_rank: Frequent Contributor
timestamp: August 07, 2014, 11:36:59 am
content: Hi allI thought i would make a stepepr motor beacuz evrything i wasfinding online was easydrive and uln2003 so i mad my self a drive that can do up to 8A ofstepper driver but i am only driving a 2A stepperhttp://eisad.blogspot.com/2014/08/transitor-unipolar-stepper-motor-driver.html

author: void_error
author_rank: Frequent Contributor
timestamp: August 07, 2014, 12:47:36 pm
content: You mean stepper motordriver.Remove the base resistors and replace the bipolar transistors with logic-level N-channel MOSFETs or any N-channel MOSFET which has reasonably low RDSat a VGSof 4-5V.

author: poorchava
author_rank: Super Contributor
timestamp: August 07, 2014, 01:05:21 pm
content: It's not a stepper motor driver, this is only 4 low-side switches and nothing more. This circuit isn't any better than ULN2003 one. Unipolar driving doesn't make sense, because you can get inegrated bipolar current-mode drivers for anything up to 3A/phase without problem, and you get microstepping for free (which you can't do on arduino at any reasonable rpm).Making a discrete atepper driver for such low current doesn't make sense and for more power you can use integrated bridge controller like A4989. Only reason to make it discrete would be to improve even further, work at extremly high rpm or something like that, but that would call for a DSP or FPGA, not an arduino.Unless you want this stepper to do something completly imprecise and unimportant, then your driver is fine. For something like 3d printer or cnc mill - forget it.

author: Isad
author_rank: Frequent Contributor
timestamp: August 07, 2014, 03:22:15 pm
content: Quote from: poorchava on August 07, 2014, 01:05:21 pmWell 3d printin and cnc i would love to but nah to have the roomi have STK6713BMK4 fixed current stepper motor driver but i burned one so i thought i would test it on this onei know it wont do anything great but its just for testin so i am not trying to make it perfect drive it just it just for funi know i cant do anything with it but it has some torque.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 08, 2014, 01:22:57 am
content: http://www.ebay.com/itm/Stepper-Motor-Driver-Controller-Board-Speed-Adjustable-with-Remote-Control-/281211769231?pt=LH_DefaultDomain_0&hash=item417987118f

author: Isad
author_rank: Frequent Contributor
timestamp: August 08, 2014, 09:45:56 am
content: Quote from: Alex Eisenhut on August 08, 2014, 01:22:57 amYeah but it dosnt ship to Albania
Easy way to get dual 8-12V +/- supply from 5V - Page 1
Forum section: electronics / projects

author: janengelbrecht
author_rank: Regular Contributor
timestamp: November 09, 2015, 04:33:06 am
content: I need to make a dual supply to opamps from +5V : range : +/-8 to 12VMy first idea was to use a MAX232 (charge pump). The OPAMP is OPA4342.Voltage Output Swing : min -8V to +8V : 16VThe system is powered from USB: 5VI realise that i cant get more than a few milli amps from a MAX232.Any other ideas for implementing this supply if noise levels also has to be minimal and component count has to be kept at a minimum?

author: Ste
author_rank: Newbie
timestamp: November 09, 2015, 05:43:16 am
content: Sounds like you need a boost regulator and an inverting regulator. Linear Tech has a couple duals which can handle this for you:http://www.linear.com/product/LT3463http://www.linear.com/product/LT3471Another option is just using a single boost and using single supply opamp biasing techniques. However, the design might be more complicated and could net you more components than you would save from not using the 2nd regulator.

author: Ian.M
author_rank: Super Contributor
timestamp: November 09, 2015, 06:40:29 am
content: Murata CMR0512S3C 0.75W DC-DC converter, 5V in +/-12V out. Good for about 30mA out at a bit under 200mA in, with 8mV worst case output ripple.http://uk.rs-online.com/web/p/isolated-dc-dc-converters/8163465/

author: janengelbrecht
author_rank: Regular Contributor
timestamp: November 10, 2015, 01:06:55 am
content: Thx good inputs...something to work on

author: obiwanjacobi
author_rank: Super Contributor
timestamp: November 10, 2015, 07:20:20 am
content: http://www.ebay.com/itm/DC-Boost-Step-Up-Voltage-Converter-Positive-Negative-Dual-output-3-6V-to-5-32V-/390967074930
EasyDDM questions - Page 1
Forum section: electronics / projects

author: Toro_Kun
author_rank: Newbie
timestamp: April 20, 2023, 05:43:57 pm
content: So recently I picked up a Siglent bench multimeter. I ran the software executable from the official site through the virus total website and hybrid analysis. Both times came back with it being reported as malicious. I was wondering if this is a false positive or what