hybridfree/eevblog-posts huggingface dataset:
Differential probes vs insulated channels  - Page 1
Forum section: electronics / projects

author: Miyuki
author_rank: Frequent Contributor
timestamp: April 29, 2016, 02:38:55 pm
content: Hi I'm no sure where to post this questionI want to discuss about pros and cons of this two solutions:Differential probes vs insulated channelsEven DIY probes and triggering two insulated scopesWhat is strong and weak sides of this two ways ?

author: Marco
author_rank: Super Contributor
timestamp: April 29, 2016, 08:17:12 pm
content: There are multiple styles of differential probes.Compared to most high voltage differential probes using a scope with insulated channels will have lower noise, because high voltage differential probes generally have a 100x divider at the differential inputs.Low voltage high speed differential probes often do their differencing near the probes, this allows them to put a much smaller capacitive load into the circuit you are measuring compared to a normal scope probe (insulated channel or not).

author: tautech
author_rank: Super Contributor
timestamp: April 29, 2016, 08:40:54 pm
content: Quote from: Miyuki on April 29, 2016, 02:38:55 pmWhat are your real test requirements?

author: bson
author_rank: Unknown
timestamp: May 01, 2016, 06:25:03 am
content: If you already have a scope, then an inexpensive low-bandwidth (say, 25MHz) HV differential probe will let you freely probe a power supply using your existing scope. A bench scope will likely have a better screen, higher bandwidth, higher sample rate, more channels, digital MSO features, more memory, more compute power, and cost less than a handheld.A high-bandwidth, low-voltage differential FET probe on the other hand is a completely different animal that will be cumbersome to use without a full-featured scope with an intelligent probe interface.
Differential scope probe--with gain - Page 1
Forum section: electronics / projects

author: Wimberleytech
author_rank: Super Contributor
timestamp: April 07, 2019, 02:37:44 pm
content: This weekend, under pressure to get some results, I needed to measure current in a feedback path--a relatively low current--microamps. In this application, I could afford to put a series resistor (suffer the burden voltage that resulted) to get something to measure with my scope using two probes and taking the difference (CH1-CH2). However, there was just not enough sensitivity for a good reading.Some time back, I made an EKG amplifier using an AD624, so I thought, hey why not? I got it out of the "project" bin, modified the gain to 100 and used it to make the measurement. Fortunately, at a gain of 100, the BW was sufficient, and there were no common-mode issues to contend with when powered with +/-15V.It worked. I used a 1k resistor, which seems big, but for this application, not an issue.Showing the schematic is a bit laughable because the AD624 requires almost no external components but here it is anyway.
Differential signal Ground - CAN bus - Page 1
Forum section: electronics / projects

author: mattko
author_rank: Contributor
timestamp: February 01, 2019, 12:38:50 pm
content: Hello,I have some doubts about differential signals and their grounding, mostly CAN bus.If I understand correctly, you do not need a GND wire to go with differential pair wires IF the "Absolute maximum: CANH DC voltage versus GND" is high enough. In other words, to keep common mode voltage on the differential pair in a small range, you need a GND wire. Is that correct? How to ensure that common mode voltage (CANH+CANL/2) will remain inside the specified tolerance?And if you don't have a GND wire, then common mode EMI is not a problem?I read some articles, but my doubt remains.Thanks!

author: capt bullshot
author_rank: Super Contributor
timestamp: February 01, 2019, 12:51:50 pm
content: CAN is designed to work with all transceivers tied to a common GND potential. As RS485 is.This stuff simply won't work reliably without the common GND.If used correctly (including the common GND) the internal circuitry of the transceiver chips "magically" take care of the common mode voltage at the transmitting side. For the receiving side, it's up to you to provide the receiver with the correct GND potential.In some (rare and special) cases CAN (and RS485) will work without a solid GND connection, the common mode level could be restored by some kind of resistive divider or clamping diodes then. But the result will be way more sensitive to all kind of EMC disturbances.Inserting a transformer (to isolate the GND potentials) makes 2-wire (without GND) differential signal transmission work in the real work (like Ethernet).
Differential signalling terminology - Page 1
Forum section: electronics / projects

author: jeremy
author_rank: Super Contributor
timestamp: October 08, 2021, 12:20:46 pm
content: Hi all,What is the correct way to distinguish (in terms of terminology) between pairs of differential signals that- have the positive line swing from 0V to a positive voltage and the negative line swing from 0 to a negative voltage- both positive and negative lines only swing from 0 to a positive voltageIn both cases, signals on the pair are complementary. Is there any standard terminology here?

author: Terry Bites
author_rank: Super Contributor
timestamp: October 08, 2021, 02:10:01 pm
content: There is no one standard. There are loads of standards. Whats your application?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 08, 2021, 04:12:02 pm
content: That is correct, AFAIK there is no one standard. What you do is refer to the signalling technology like thisPECL diff pairLVDS diff pairDDR diff pairetc and it will be that way you identify the specific signalling scheme

author: Wolfram
author_rank: Frequent Contributor
timestamp: October 08, 2021, 04:23:11 pm
content: The difference between the two cases you mention would be called the "common-mode voltage" of the signals. The first case would have zero common mode voltage, provided the voltage swing is symmetrical.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 08, 2021, 04:37:56 pm
content: Bipolar vs. unipolar, I suppose. RZ/NRZ may also be relevant but that's usually in terms of pulse coding where the line returns to zero for each bit, not in terms of what the logic levels are.The logic levels can be absolutely anything, what counts as '1' or '0' or "zero" or "open" is entirely free.CAN, and RS-485 to the extent that it uses an open-line condition*, are examples of such a signaling method as you propose. CAN is driven H/L or left open, much as I2C and other single-ended, open-collector buses are driven L or left open (and, indeed, you can get differential I2C extenders, which use the same logic on a differential bus -- alas, mind that they still aren't as noise-immune as CAN).*CAN was originally implemented using RS-485 transmitters strapped to transmit '1', and wiring data to the enable input. RS-485 normally reads open-line as inactive or '0', not distinguishing between driven-low and open-line.Most differential drivers are bipolar, like Alex's examples. The transmitter is only slightly more complicated than otherwise (typically some manner of H-bridge looking thing, typically plain logic output pins, with LVDS and CML being more complicated, or exceptional**), and the differential swing is doubled, a nice step up on noise immunity.**Hmm, I suppose CML is another unipolar example, unless there are also examples where it's bipolar, I'm not sure. As I recall, offhand, these are usually open-collector/drain (so, push-pull), like 10/100 Ethernet PHYs, HDMI, and on a somewhat less digital basis, a number of signal generator and RF transmitter ICs.Tim
Differing Response in Transient vs AC Analysis in LTSpice - Page 1
Forum section: electronics / projects

author: TeddyPython
author_rank: Contributor
timestamp: May 31, 2020, 08:01:53 pm
content: I'm trying to design a HV differential probe as a project which should teach me more about op amps (so far I've only covered just simple 10's kHz amps). After some background reading, I settled on trying to achieve the following specs:+-500V input (AC+DC)20MHz bandwidth (-3dB)+-5V output (100:1 attenuation)And I've created the following circuit as a starting attempt:With some op amps I have chosen for their high input Z, high bandwidth, and relatively low cost. When I perform an AC analysis the circuit seems to have a very flat gain with <1dB of ripple - the following says I should expect values very close to 5V up to just over 20MHz.However, when I perform a transient simulation at 20 MHz I see the output is much smaller when compared to 5 MHz.20MHz:5MHz:Why am I seeing this difference between simulation types in LTSpice? Or rather, how should I be interpreting these two different simulations? Presumably I'm not understanding the output of the AC analysis.I've also included the schematic file for LTSpice if anyone would like them.

author: Someone
author_rank: Super Contributor
timestamp: May 31, 2020, 10:45:11 pm
content: Depends on the opamp models, try switching them to "ideal" infinite speed devices and see if the results match.GBW != slew rate

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: May 31, 2020, 11:24:53 pm
content: TeddyPython,Quote from: Someone on May 31, 2020, 10:45:11 pm+1Here is a slightly different model:I placed the AD817 on the schematic and used the symbol for a generic op-amp. Doing it this way it is portable.I am stepping the Frequency so that I can both results on the same graph.If I test at 100V peak I get a result consistent with the AC analysis.At 500V peak it is amplitude limited. This indicates a slew rate limitation.eevblogprobe_JDB.asc(7.36 kB - downloaded 33 times.)Regards,Jay_Diddy_B

author: TeddyPython
author_rank: Contributor
timestamp: May 31, 2020, 11:36:10 pm
content: I see, thanks both for the information.Also thanks Jay for the tip making the schematic more portable.I will look for a faster slew rate op amp tomorrow and report back.

author: TeddyPython
author_rank: Contributor
timestamp: June 01, 2020, 06:18:11 pm
content: I've done some tests with a THS4631 and the result is much better, indeed gain is acceptable (to me) up to almost 25MHz at +-500V, or +-700V at 20 MHz. This did need some small capacitances though, but I was thinking these might occur from parasitics anyway, or could be added with some wires bodged over components. Alternatively, is there a better way to get a decent response without resorting to such small capacitances?Also included another version of the spice schematic.
Difficult to find datasheet, LTC939CS - Page 1
Forum section: electronics / projects

author: ehobby
author_rank: Contributor
timestamp: March 25, 2022, 04:47:43 am
content: I am looking for the datasheet for the LTC939CS voltage regulator IC, which seems to be near impossible to find. Been hunting this for quite a while. Have looked in Linear databooks from around 2000 (based on the date codes of the chips I have) and all over the web, including the Linear/Analog website. I also could not find it in the IC Master books I have. I suspect if anyone has one it is probably in paper form or part of a application note from Linear.Thanks

author: Terry Bites
author_rank: Super Contributor
timestamp: March 25, 2022, 12:43:05 pm
content: Drop the CS part and prepare for awe!

author: magic
author_rank: Super Contributor
timestamp: March 25, 2022, 05:12:13 pm
content: Nope, all you get is a DigiKey page (obsolete item, no docs) and some spam.This is literally the only remotely relevant document I found.https://www.analog.com/media/en/technical-documentation/reliability-data/r245.pdfAt least it confirms that the part really existed.

author: amyk
author_rank: Super Contributor
timestamp: March 26, 2022, 12:26:05 am
content: Have you tried asking Linear/Analog directly?
Difficulty finding suitable DC-DC - Page 1
Forum section: electronics / projects

author: RoG
author_rank: Newbie
timestamp: July 04, 2025, 03:08:01 pm
content: I have been struggling to find a high efficiency (95%+) buck or buck boost (ideally) DC-DC converter with the following specs:Input 40V to 60VDC (minimum) 11V to 60VDC (desired)Output 27VDC (minimum) 32VDC (desired)Output current 40 amps (minimum)Closest thing I have found is a board mount module that does have enticing specs of 9-60VDC input, 0-60VDC output and 50 amp output current.It seems to be unobtainium though. This is the product: H60SB0A050NRDC by Deltahttps://www.digikey.com/en/products/detail/delta-electronics/H60SB0A050NRDC/9598973?s=N4IgjCBcoLQCxVAYygMwIYBsDOBTANCAG4B2aWehA9lANogBsDYAHAOwgC6hADgC5QQIAL6igA

author: coromonadalix
author_rank: Super Contributor
timestamp: July 04, 2025, 04:02:52 pm
content: unless you go for thing like theses, your delta dc-dc has a very long lead time, and 0 qty on all major sites ...https://www.aliexpress.com/item/1005009213877532.html?but 25 amps ?https://www.icstation.com/1200w-high-power-boost-converter-step-transformer-adjustable-charging-power-supply-electric-vehicles-solar-power-p-16135.html20 ampsor put them in parallel if your output voltage and or current are fixed ?https://www.aliexpress.com/item/1005007345671169.html?40 amps ?as for reliability ?

author: mtwieg
author_rank: Frequent Contributor
timestamp: July 04, 2025, 04:37:31 pm
content: Even your minimum requirements are pretty specialized (>1kW out, with a peculiar output voltage), not something I would expect to find regularly stocked at digikey/mouser.Are you looking for a one-off, or do you intend to use it in a product? If the latter I would reach out to Delta/TDK/Vicor/Artesyn/etc.
Diffusion grid pin on VFD display - Page 1
Forum section: electronics / projects

author: Rolo
author_rank: Regular Contributor
timestamp: July 20, 2018, 01:08:20 pm
content: I'm exprimenting with a VFD display, I thought I knew the VFD principles but this model has a "Diffusion grid" pin. I have not seen that before. I suspect it has something to do with the size of the display, the digits are 15 mm high and it has only three filament wires.It's the second pin from the left and it goes to the top glass with a little metal spring.I have a section of the datasheet but that does not mention this pin, google does not help alot.Anyone knows what the the function of this pin is and how to connect it? So far I have the best results if I connect it to the high voltage rail.Thanks.

author: Ian.M
author_rank: Super Contributor
timestamp: July 20, 2018, 01:20:19 pm
content: http://www.futabahk.com.hk/fts/-%20FTP_DataBase/Docs_05TechDocs/VFD/AN-1103A-EN%20%20VFD%20Characteristics%20and%20Operation%20Guide%20(EN).pdfPage 13, section 6.5.Tie it to the cathode bias voltage. If that results in luminosity striping it may need to be taken positive via a resistor.

author: Rolo
author_rank: Regular Contributor
timestamp: July 20, 2018, 01:32:57 pm
content: Thanks!
dig your way into rubber podding ? - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: November 29, 2022, 09:19:46 am
content: omg it is not always fun to dig your way into poddingsome is made of stone hard epoxyother times it is soft and funny to cut in,what is your tricks ?here a video of a fun nighthttps://youtu.be/c3ouyDKOLFs

author: Terry Bites
author_rank: Super Contributor
timestamp: November 29, 2022, 03:46:56 pm
content: You can make epoxy fall to bits just by boiling your thing for 10 min untill the whole thing gets to 100 real degrees.For silicone use Dichloromethane (DCM), this makes the rubber crumbly.Some people say that an overnight soak in transmission fluid kills silcone. Never tired it myself.

author: themadhippy
author_rank: Super Contributor
timestamp: November 29, 2022, 05:57:02 pm
content: QuoteMake sure its old school acetone based,loads of the stuff is now "eco friendly" and wont be any good

author: xmris
author_rank: Contributor
timestamp: November 30, 2022, 10:03:23 am
content: Quote from: oz2cpu on November 29, 2022, 09:19:46 amargh...the PSU of my C64 is like this.

author: SeanB
author_rank: Super Contributor
timestamp: November 30, 2022, 02:15:37 pm
content: Had some of the rock epoxy, so dropped the whole lot into a bottle of MEK, and left it there for 3 months, till the epoxy was soft enough to pick off. The little PCB in the middle did not survive, but at least I was able to see what it was, which was a simple JFET buffer module for some chart recorder, of which I only had the buffer. Resistors all I had to measure as they also lost the paint. The capacitors, metal film, were dissolved.
DigiKey Fetch Tool (BOM helper) - Page 1
Forum section: electronics / projects

author: ColdKeyboard
author_rank: Contributor
timestamp: April 17, 2020, 06:23:38 am
content: Hey guys,Just wanted to share this tool that I made a while back for myself and been using it daily ever since.You provide URL to DigiKey component, and the script fetches all relevant information (MFG, MFG PN, DK PN etc)and you can use shortcuts i.e. CTRL+1/2/3/4/5... to paste/type that information into currently selected field.Shortcuts are global so it's really nice not having to do Alt+TAB `bajilion` times while working on a BOM.Here it is in actionhttps://www.youtube.com/channel/UChfv7Rkm2hvAxlqKvjzFcUAAnd here is the link to the GitHub repository where you can give it a try.Note there are two branches, one copies information to your clipboard while other types information via keyboard key-press emulation.https://github.com/SasaKaranovic/DigiKeyFetchLet me know what do you think and if you find it useful.

author: ColdKeyboard
author_rank: Contributor
timestamp: April 18, 2020, 12:58:56 am
content: No love for BoM tools?Would love to hear some feedback and if you guys find this useful. Also tips and tricks are always welcomed.
DigiKey MA1026 clock module - Page 1
Forum section: electronics / projects

author: muephonic
author_rank: Newbie
timestamp: March 28, 2020, 01:34:26 pm
content: I am looking for schematics and instructions for a vintage 1980s DigiKey digital clock module - MA1026. Anyone out there have this one?

author: rvalente
author_rank: Frequent Contributor
timestamp: March 28, 2020, 05:13:53 pm
content: Found on google....

author: floobydust
author_rank: Super Contributor
timestamp: March 29, 2020, 03:38:28 am
content: Did you know the early National Semiconductor COB clock modules literally made Digikey:"Digi-Key Corporation founder and Chairman Ron Stordahl officially began purchasing components from National Semiconductor for his new distribution business in 1973.Although many of National's parts sold well, it was the sale of thousands of National Semiconductor clock modules that played the most significant role in terms of both sales and profits that fueled Digi-Key's growth during its early, critical years of business."MA1002 4-digit, 0.5" LED (main LSI MM5385/12hr or MM5386/24hr)MA1003 VFD automotive clock module (LSI is MM5377)MA1010 4-digit, 0.84" LED (main LSI MM4391/12hr or MM4392/24hr)MA1012 4-digit, 0.5" LED (main LSI MM4391/12hr or MM4392/24hr)MA1013 4-digit, 0.7" LED (upgrade from MA1012)I ran a MA1010 for many years, it's PMOS and sensitive to ESD and one winter it died from a zap on the buttons.The modules need a dual winding power transformer (one for LEDS and one for IC).I'm not sure why they were not a commercial success.First job I used to repair clock radios in a repair shop in the 1980's, we got $5 for every unit fixed flat rate. They were all 40-pin DIP clock IC's and Taiwan builds, pretty cheap inside.

author: w9gb
author_rank: Contributor
timestamp: April 15, 2025, 07:03:39 pm
content: National Semiconductor MA1026 Clock Modulehttps://www.wass.net/othermanuals/MA1026.pdf

author: Benta
author_rank: Super Contributor
timestamp: April 15, 2025, 07:40:14 pm
content: Wow. Worst soldering I've seen.

author: floobydust
author_rank: Super Contributor
timestamp: April 15, 2025, 08:11:38 pm
content: Same as modern china- ain't nobody got time to heat a joint enough for flow to the other side of the PCB. Works fine as long as the solder gets on a pad or plated through tunnel etc. but makes me cringe so much too.National Semiconductor invested many millions and was way ahead with the chip-on-board and LED on board technology. Early 80's Philippines, Indonesia. But you see it still needed hand-soldering. COB with through-hole is a bad idea. Something happened and NS kibosh'd the entire technology sold it all. I think it did not pay off, was done too expensive, or got copied by Asian manufacturers.I worked in an electronics repair shop in the early 80's and you never saw these NS modules in consumer products. It was the usual DIP-40 clock chip and the LED display was LED die-on-board.MA1026 had the LM334 temperature display feature, totally novel, as well as the usual alarm clock.
Digikey or Mouser part for 20 pin JTAG connector? - Page 1
Forum section: electronics / projects

author: FrankBuss
author_rank: Unknown
timestamp: July 25, 2018, 01:25:40 pm
content: I'm searching this connector for building an adapter for my Segger J-Link programmer:20 positions, 2 rows, 2.54 mm pitch, female pin header connector, right angle, through hole. After some search I found this:https://www.digikey.de/short/j5vdnbI could use it, but it would be perfect, if it would have this small bump in the middle to prevent connecting it the wrong way. Does someone know a part number for this for Digikey or Mouser?

author: timpattinson
author_rank: Contributor
timestamp: July 25, 2018, 01:53:07 pm
content: Try some of these:https://www.digikey.de/products/en/connectors-interconnects/rectangular-connectors-headers-receptacles-female-sockets/315?keywords=&sort=&pv88=34&pv1790=1&pv2172=i2&pv5=4123The keyword (haha!) is "polarising key"Sent from my SM-G930F using Tapatalk

author: bson
author_rank: Unknown
timestamp: July 25, 2018, 02:01:08 pm
content: Molex 70247-2054 for the male counterpart

author: FrankBuss
author_rank: Unknown
timestamp: July 25, 2018, 02:11:24 pm
content: Thanks!https://www.digikey.de/short/j5vvw3looks perfect. The German word was "Kodierstift", slightly better than polarising key

author: carljrb
author_rank: Contributor
timestamp: July 25, 2018, 04:27:24 pm
content: Quote from: FrankBuss on July 25, 2018, 02:11:24 pmThat's theexactmodel I use on my J-Link to CortexM adapters. I can confirm it works perfectly!

author: FrankBuss
author_rank: Unknown
timestamp: August 09, 2018, 09:41:51 pm
content: Boards arrived, looks nearly like one of these overpriced original Segger adapters, except for my bad soldering skillsPS: good idea that I placed the connector near the edge. It is slightly more difficult to solder, but if there were parts of the PCB underneath, it wouldn't fit in the J-Link.
Digikey/Mouser for socket pins? - Page 1
Forum section: electronics / projects

author: robertbaruch
author_rank: Regular Contributor
timestamp: December 24, 2016, 11:35:52 pm
content: I'm looking for pins like this [ebay search] (1mm pin sockets) except on Digikey, Mouser, Element14, or whatever.I can't seem to find the right category or combination of parameters. I keep coming up with crimped connectors, even when I specify solder tail. Where can I find these things?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 25, 2016, 06:02:49 am
content: Are you looking for "Rectangular - Board to Board Connectors - Headers, Receptacles, Female Sockets" (as Digikey calls them)?Tim

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: December 25, 2016, 05:00:40 pm
content: Those look like some kind of PC mount version. I'd try looking through the AMP or similar catalog for connector pins, and what options they offer. Then try a search on that part number with the usual suspects like Digikey. You might have to try somebody like Allied, as it's a bit odd.

author: robertbaruch
author_rank: Regular Contributor
timestamp: December 25, 2016, 06:22:54 pm
content: I'm pretty sure these are PCB-mount pins for female D-sub connectors. However, I haven't had any luck finding them except on ebay. I would probably have more luck finding surplus PCB-mount female D-sub connectors and pulling the pins!

author: cdev
author_rank: Super Contributor
timestamp: December 25, 2016, 06:59:14 pm
content: They might be pins for some larger older (Amphenol?) interconnect assembly. Just a wild guess based on them looking quite like the pins for a multi-conductor plug and socket assembly that I have a bunch of parts for.
DigiKey/Newark-type of online store for Pneumatic components?  - Page 1
Forum section: electronics / projects

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: July 17, 2017, 10:03:36 pm
content: Hi,I am wondering if anyone know what is a good online distributor like Digikey for but Pneumatic components? I need an AND gate and integrator, vacuum switch, pipes, mufflers and adapters and ... bunch of small things. Google returned billion sites. Where do you guys buy all your pneumatic parts?Thanks in advance!

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: July 17, 2017, 10:26:27 pm
content: Quote from: evb149 on July 17, 2017, 10:08:30 pmYes, I was checking the "usual" places. These guys are not exactly good sources for components I am looking for. This company, for example, has good supply of solenoid valves:https://www.stcvalve.com/Solenoid_Valve.htmbut they only sell their own, made in China stuff and everything else I need to get elsewhere, meaning a shipping cost for every small piece of pipe etc. Ordering Is complicated thing too. So I wonder if There is Digikey for electronic components, Edmunds Optics for optics then should be one for pneumatics ...

author: Wolfram
author_rank: Frequent Contributor
timestamp: July 17, 2017, 10:45:27 pm
content: RS electronics have some pneumatic components listed. Alliedelec seems to be the north-American department of the same company, and they also have some pneumatics listed:https://www.alliedelec.com/pneumatics/

author: jpanhalt
author_rank: Super Contributor
timestamp: July 17, 2017, 10:53:26 pm
content: Grainger and McMaster, while having a large selection, will be expensive. Grainger seems to have bought into the"discount" marketing scam (like everyone gets 20% off or more). Think of Harbor Freight. McMaster is high, but not too bad.For pneumatics per se, I don't have anything else to suggest, except Google For hydraulics, I go tohttp://pressureconnections.com/default.aspx?page=item+detail&itemcode=1404R-04-04-.032,which is in Columbus, OH. Their prices have been quite reasonable and service is good (I am in Clevelan, OH). Don't know about export to Canada.John

author: Nusa
author_rank: Super Contributor
timestamp: July 17, 2017, 11:03:25 pm
content: Mitsumi may carry what you need -- link to pneumatics section:https://us.misumi-ec.com/vona2/mech/M1900000000/Pneumatics isn't my thing, but I've ordered extrusions and hardware from them before.

author: garboui
author_rank: Regular Contributor
timestamp: July 17, 2017, 11:59:47 pm
content: Automationdirect.com will have some but not exhaustive. (on a side note their hook up wire is a good deal)www.thepneumaticstore.com/
Digilent Analog Discovery 1Gen with LabVIEW(with English language updated)  - Page 1
Forum section: electronics / projects

author: ewb_topic
author_rank: Newbie
timestamp: March 05, 2016, 02:03:55 am
content: Anyone can use Digilent Analog Discovery 1Gen with LabVIEW build .exe fileswe have update this free project with english language(2016.1.7)Demo Videohttps://www.youtube.com/watch?v=C7PB4OiY0ko&feature=youtu.beUpdate2016.1.25————————————————————————If you have a digilent Digilent Analog Discovery 1gen,and you want use a LabVIEW sytle program with Digilent Analog Discovery 1Gen.Great Now,you can download a LabVIEW build .exe file, Please flow me~~~——————————Step 2: Install Digilent Waveform 2.7.5install Digilent Waveform 2.7.5https://www.digilentinc.com/Data/Products/WAVEFORMS/digilent.waveforms_v2.7.5.exe——————————Step 3: Install LabVIEW 2015 Run-timeDownload LabVIEW 2015 Run-time blewhttp://ftp.ni.com/support/softlib/labview/labview_...——————————Step 4: Download HLS.exe (AD_UN)Use HLS to measure your Lab.Have a great dayDownload HLS.exelink:release updated 2016.1.7?https://drive.google.com/file/d/0B4qLG-ef0x1mamMtYUNjN1JPTFE/view?usp=sharing——————————ok?make pin connect like that?* this .exe file is a free project?but user must submit your device?Analog Discovery 1? sn tosupport.tla@foxmail.comif anyone has any error message about this .exe Project ?you can send email to support.tla@foxmail.comThanks AllSupport.TLA@foxmail.comwww.sh-chengtec.com

author: ewb_topic
author_rank: Newbie
timestamp: March 25, 2016, 12:39:59 am
content: some friends Outside China cant download this zip filenow we put this zip file on google driverplease download belowhttps://drive.google.com/file/d/0B4qLG-ef0x1mamMtYUNjN1JPTFE/view?usp=sharing

author: ewb_topic
author_rank: Newbie
timestamp: August 31, 2016, 04:09:13 am
content: new upload vedio in youtubehttps://www.youtube.com/watch?v=C7PB4OiY0ko&feature=youtu.be

author: Evi
author_rank: Regular Contributor
timestamp: March 09, 2017, 04:00:53 pm
content: Device connected but, not work
Digital 2 channel super-het receiver installation - Page 1
Forum section: electronics / projects

author: Dahlander
author_rank: Newbie
timestamp: February 12, 2021, 12:43:50 pm
content: Hello, I recenlty build a new horizontal sliding garage door. I installed the mechanism with no problem following the manual, some parts were hard but i finally managed it. So, the door i want to talk about is the second door there is at my property, so i asked at the store if it's possible to open both doors with the same controller (with different buttons of course). For this purpose they gave me an electronic device that i am supposed to patch into the PCB of the second (old) door i want to use it for.I opened the old mechanism, here i have to mention that i was not able to find any manual about the electronics of this door, and i see two PCB that get the job done. The guy at the store told me that the device have to get power from the low voltage input and next find the input for the button (the button that comes wired to open the door) and patch the relay one there.Opening the mechanism i faced two PCB, i can recognise the low input connector strips, but i cant tell where the input for the button i am supposed to connect the relay one is.The best practise problably is to call an electrician, but i have taken this personally.Below there are the photos of the pcb's and the patch device:The device:https://imgshare.io/image/pwXLld1st pcb:https://imgshare.io/image/pwXuhp2nd pcb:https://imgshare.io/image/pwXGVHThe device manual:https://www.sfkshop.gr/wp-content/uploads/2020/06/dektis-rec3003pico-2ch.pdfThe mechanism is an old italic aprimaticAny help is more than welcome.Thank you.

author: m k
author_rank: Super Contributor
timestamp: February 13, 2021, 02:17:43 pm
content: Yes,better call an electrician.The device is a simple connector.Possibly supposed to be used as a door motor switch, but it can't act alone.It can select a direction but something else must be an enabler, something like a limit switch for cutting the motor off.It can also start an operation but something else must do the rest.NO = normally openNC = normally closedThe used part at left is closed when antenna signal is received.Center can be eighter way.If connections in the picture are what are currently in use with one door and other door is similar then you connect the other door switch to COM and NO.Pcb pictures are missing too many things.
Digital adjustable brick wall low pass filter - Page 1
Forum section: electronics / projects

author: OgreVorbis
author_rank: Newbie
timestamp: August 22, 2019, 11:46:51 pm
content: Hi,I am in need of an adjustable brick wall filter. I'd actually prefer a studio style rack mount unit, but it looks like this is going to have to be something I build myself because I can't find anything.I plan to use this chip:https://www.digikey.com/product-detail/en/maxim-integrated/MAX294CPA/MAX294CPA-ND/1512387And to generate a clock signal for it using Si5351A to adjust the corner frequency.Is this a good way to go about doing this? Will there be noise from the clock signal? Is it stable enough?Maybe there is already a directly programmable filter out there, so I eliminate the need for the clock?

author: ledtester
author_rank: Super Contributor
timestamp: August 23, 2019, 02:53:06 am
content: I would just try it. The chip is advertised as "easy to use", and "no external resistors or capacitors required" so there shouldn't be a lot of complications.Be sure to read page 7 of the datasheet especially the section "Uncommitted Op-Amp" - it can help with clock noise filtering among other things.A google book search for "max293 circuit" got some hits in "Analog Circuits Cookbook" by Ian Hickman, so checking that out might help.

author: ledtester
author_rank: Super Contributor
timestamp: August 23, 2019, 03:09:01 am
content: For more discussion on aliasing, have a look at the section "SAMPLED DATA SYSTEM CONSIDERATIONS" from the MF-10 datasheet (p. 26):https://www.ti.com/lit/ds/symlink/mf10-n.pdf

author: coppercone2
author_rank: Super Contributor
timestamp: August 23, 2019, 03:58:48 am
content: those digital smfilter chips usually have a clock noise spec some where.I want to say LT used to sell the same chip or something based on the same die, so you can find the LT equivalent to see if its not thereit says clock feed through 5mVppthey have continous time filters too, but the impedances tend to be high.
digital buffer delay components  - Page 1
Forum section: electronics / projects

author: john23
author_rank: Frequent Contributor
timestamp: July 01, 2024, 04:07:21 pm
content: Hello,I am using 74ABT04 HEX inverter to create a good high quality delay and pulse rise and fall.However when i cascade 4 of them i get only 6ns delay from the input and output as shown below.Is there some digital buffer component which will create a delay of 50ns for example?Thanks.

author: TimFox
author_rank: Super Contributor
timestamp: July 01, 2024, 04:15:45 pm
content: There are packaged devices that use an L-C delay line between buffers.There are also programmable and tapped delay lines.https://www.mouser.com/c/semiconductors/integrated-circuits-ics/clock-timer-ics/delay-lines-timing-elements/

author: ajb
author_rank: Super Contributor
timestamp: July 01, 2024, 07:23:34 pm
content: How accurate does the delay need to be?You could add an RC delay between your existing buffers, but that might not be practical for a very precise/stable delay in a real circuit. You'd also want to use schmitt-trigger inverters (74x14) rather than 74x04.

author: edavid
author_rank: Super Contributor
timestamp: July 01, 2024, 07:34:57 pm
content: First of all, don't expect a simulation (or solderless breadboard prototype) to be accurate here.Second, 74ABT is just too fast for this.Use a slower logic family - 74HC is probably best. Build a dead bug prototype.A bonus is that you can tune the delay by adjusting the supply voltage.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: July 01, 2024, 08:17:48 pm
content: Quote from: john23 on July 01, 2024, 04:07:21 pmLOGIC delays are spec'd at some load capacitance, and they have large spreads from MIN to MAX.How accurate do you need the 50ns and does it need to track CMOS temperature variations ?You can get 50ns with schmitt and RC elements, with some caveats.It needs a clean drive pulse, so may need the RC element between schmitt gates.A simple RC delay needs a settling time before being reused, otherwise the off time can modulate the on time.It would need calibrate in circuit, as PCB and stray C will be important.It should use the same vendor part in production
digital buffer/switch - Page 1
Forum section: electronics / projects

author: Simon
author_rank: Unknown
timestamp: June 26, 2014, 11:52:02 am
content: I'm having trouble finding what I want probably because I don't know what to call it.I'm looking for a digital buffer, preferably so that I can connect two outputs together so that the signal can come from one or the other input and of course the buffers need to have an enable pin. What do I need ? what is available ?

author: onlooker
author_rank: Frequent Contributor
timestamp: June 26, 2014, 12:07:21 pm
content: Multiplexer, or input selector ic assuming you need only pass the current logic level, not really buffering/storing multi bit data stream.

author: Simon
author_rank: Unknown
timestamp: June 26, 2014, 12:19:38 pm
content: ok, infact I suppose the 7400 range has something

author: kizzap
author_rank: Unknown
timestamp: June 26, 2014, 01:51:15 pm
content: 4051?

author: TheGreatGooglyMoogly
author_rank: Contributor
timestamp: June 26, 2014, 04:25:38 pm
content: Couple ideas from things we use at my work:CMOS Switch - PI3C3125 type -http://www.pericom.com/assets/Datasheets/PI3C3125.pdfProp delay is 0.25 ns and the enable is like 1.5 ns.Tri-state buffers:http://www.nxp.com/documents/data_sheet/74HC_HCT125.pdfWe use the Pericom chip to switch a 27 MHz and a 74.25 MHz clock to a video chip.

author: jlmoon
author_rank: Unknown
timestamp: June 26, 2014, 05:25:28 pm
content: Quote from: Simon on June 26, 2014, 11:52:02 amI'm questioning your last part of your requirements.. "connect two outputs together so that the signal can come from one or the other input"? Are you requesting a input multiplexer or a output mixer?if a switch or multiplexer .. how fast?

author: rob77
author_rank: Super Contributor
timestamp: June 26, 2014, 05:55:11 pm
content: you need a buffer/line driver or transparent latch with high-impedance output.for example :74HC244 - buffer74HC373 / 74HC573 - transparent latchboth examples are with high-Z outputs - you can wire the outputs of multiple drivers/latches together and activate the output enable on ONE driver/latch at a time.

author: Simon
author_rank: Unknown
timestamp: June 27, 2014, 06:12:26 am
content: Quote from: jlmoon on June 26, 2014, 05:25:28 pmWell i suppose I'm asking the things to do what they are meant to, connect more than one signal to the same "bus" but in my case I've only got one wire and two inputs to it and want to have one or the other pass so as long as they can tri-state I'm fine
Digital Clock - Page 1
Forum section: electronics / projects

author: Sangharsh Sharma
author_rank: Contributor
timestamp: September 29, 2018, 01:56:21 pm
content: Hello Guys....I'm planning to make a digital clock for my project without using microcontroller..The first thought that popped onto my mind was using a 4026 ic as I wouldn't have to use a decoder driver in that case...But I have to display the time in 12 hour format (AM/PM). Is it possible to display the hour format in that way using this ic...or should I use any other option? I needed your hep...Hope you got the question..Thank you

author: SeanB
author_rank: Super Contributor
timestamp: September 29, 2018, 02:10:52 pm
content: Look up Dave's clock on the YT channel ,where he used the same chip and did the decoding as well for it.

author: Sangharsh Sharma
author_rank: Contributor
timestamp: September 29, 2018, 06:09:21 pm
content: Yes, I looked at it...But in it, he has used 24 hr format..So, the clock resets to 00 when the counter reaches 24...I have to display in 12 hr format..which means after 12, I gotta display 1.....So, is it possible using this same ic and method?

author: DaJMasta
author_rank: Super Contributor
timestamp: September 29, 2018, 06:28:50 pm
content: There are counters that can be set to a specific value when reset, you could also create a second pulse from the reset to reset and increment a first time.I don't remember if Dave's does, but I always thought it was neat to use the mains frequency as your counter reference to keep things accurate. A nice little addition to consider.
Digital Clock - Page 1
Forum section: electronics / projects

author: Sangharsh Sharma
author_rank: Contributor
timestamp: December 08, 2018, 09:38:33 am
content: Hello guys...I'm making a digital clock using ics 7490, 7447 and seven segment display. It's for my college project.I'm confused actually on how to take a input clock signal in 7490 ic. I've completed the seconds counter portion. But I'm confused about the minutes portion regarding how to take input clock on 7490 ic from output of previous 7490(seconds counter). Could you help me with this? I wanted to know how each output pin of 7490 ic functions and how do we differentiate which output pin is to be used for sending clock to another 7490? Hope you got the question...I've attached the schematic for two second counters and a minute counter below...would appreciate your help..

author: StillTrying
author_rank: Super Contributor
timestamp: December 08, 2018, 12:08:04 pm
content: U2's Q2, (10s of the seconds) clocks U5 (1s of the minutes).

author: johnkenyon
author_rank: Regular Contributor
timestamp: December 08, 2018, 03:37:59 pm
content: Hint: You want the minutes counter to increment when the seconds count gets to 60.Look at the function of the AND gate U4A in your 00-59 seconds counter.Think about what happens when the count is at "5" (0101) and when it goes to "6" (0110).When the output of the AND gate goes to "1" what does it indicate, and what effect does it have on the "tens" counter?

author: Sangharsh Sharma
author_rank: Contributor
timestamp: December 09, 2018, 05:57:50 am
content: Yes, I have done that part...actually in the seconds portion, we gotta take the clock input from 11 pin...but in minute portion we take it from pin 8...why??

author: StillTrying
author_rank: Super Contributor
timestamp: December 09, 2018, 12:08:00 pm
content: "actually in the seconds portion, we gotta take the clock input from 11 pin...but in minute portion we take it from pin 8...why??"Q3 represents the decimal value '8'. The 10s of seconds and 10s of minutes never count up to the value '8' because they're reset to 0 when they reach the value '6', so you have use the previous output Q2, for acounter that only goes 0 to 5, obvious surely!http://genderi.org/tutorial-of-frequency-division.html#Decade_Counter_Timing_Diagram

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 09, 2018, 09:16:18 pm
content: Wow, this takes me back. I designed one and built two of them back in 1975. Here are the schematics.
Digital Clock - Page 1
Forum section: electronics / projects

author: Sangharsh Sharma
author_rank: Contributor
timestamp: December 13, 2018, 05:17:46 pm
content: Hello everyone...I'm trying to build a digital clock as I've mentioned in my earlier posts. I'm building a 12 hr format digital clock..I've completed the seconds and minutes portion..but I couldn't figure out the hour one...(because after 12, i gotta bring 1 in the hour counter)...so how do I figure this out? Also, how can I make the clock to set as I desire...Is it possible to simulate in a way that I can see what the clock shows in suppose 12 hours after now? Because only then, I can know my total circuit is working properly...Could you help me in any of this?? Thank you

author: metrologist
author_rank: Super Contributor
timestamp: December 13, 2018, 05:22:48 pm
content: Need more info like how are you building the clock circuit. Are you using a microcontroller?

author: JuanGg
author_rank: Regular Contributor
timestamp: December 13, 2018, 07:39:18 pm
content: I assume you are doing it with digital ICs rather than a micro.Dave has an interesting video covering the subject that may be of interest:https://youtu.be/5kGhoRuhlxM.You can hook the function gen to your circuit to make time go by "faster".Juan

author: wilfred
author_rank: Super Contributor
timestamp: December 14, 2018, 12:02:04 am
content: In the latest mailbaghttps://www.eevblog.com/forum/blog/eevblog-1154-mailbag/msg2032555/#msg2032555Dave mentions another YT channel and provides a link. "Playing with Junk"The current latest video contains a discussion on making a clock using some displays salvaged from an aircraft instrument. Even without the displays there is an interesting discussion on designing a circuit and it also shows using Logisim to simulate the circuit.Maybe you will find something useful to you there.PWJ is a channel I would recommend. It is one of my favourites.
Digital Clock with an alarm - Page 1
Forum section: electronics / projects

author: Sangharsh Sharma
author_rank: Contributor
timestamp: April 07, 2019, 05:30:44 pm
content: Hello everyone.I'm working on a digital clock circuit for my hobby project. I completed the circuit but I couldn't figure out how to add an alarm to the circuit. A little help would be appreciated. Thanks.(I've made the digital clock circuit using 7490 ic, 7447 ic and logic circuits). The simulation pic is attached below:

author: Zero999
author_rank: Super Contributor
timestamp: April 07, 2019, 06:26:02 pm
content: The easiest way would be to use a binary comparator, which would set its output high, once the numbers exceed the set value, which could be determined by BCD rotary switches.Of course it would be even easier to use a microcontroller, but this is probably an educational project to learn about logic gates, so that would defeat the purpose.
Digital control of a comparator and amplifier - Page 1
Forum section: electronics / projects

author: PeterFW
author_rank: Frequent Contributor
timestamp: March 13, 2015, 11:00:21 pm
content: Hello!I cobbled together a little circuit to detect very loud noises to trigger a interrupt on a µC.It is pretty straight forward, it works and i had a small board made.This is the schematic, R2 is currently not populated on the picture above.http://shiosai.de/gallery3/var/albums/Electronics/schematic-887181533.png?m=1426287177And here is the but...I allready use a RC filtered PWM signal to set the comparator (far right OPA) trigger level.But i would like to have digital control of the amplifier (far left OPA) ratio.This is just a single unit and maybe a few more in the future for myself but i would like to keep this very simple.The next best idea i had was just replaceing the RC Filter (C5, R15) and the gain set resistors (R5, R6) with a dual digital potentiometer.That sounds like the best solution, i could not think of a simpler xor cheaper one.Anny thoughts?Greetings,Peter

author: void_error
author_rank: Frequent Contributor
timestamp: March 14, 2015, 11:04:13 am
content: If you don't need fine gain control and rather coarse steps you could use an analog multiplexer to switch between gain-setting resistors. I think it's cheaper than a digital potentiometer.
Digital counter - Page 1
Forum section: electronics / projects

author: Ben sage
author_rank: Contributor
timestamp: December 22, 2019, 11:34:53 pm
content: Hey guys I’m wandering if my counting circuit works if any one could test it in a circuit simulator that wud be great or if any one noticed any thing that’s not right the please leave a comment whats not right think’s everyone

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 22, 2019, 11:47:44 pm
content: Quote from: Ben sage on December 22, 2019, 11:34:53 pmHere you go Ben. This is an easy tool to use. You can have the satisfaction of proving this yourself!!https://logisim.en.uptodown.com/windows

author: Ben sage
author_rank: Contributor
timestamp: December 23, 2019, 12:23:45 am
content: Sorry I guess I should have told all of you at I am only 15 years old and I don’t have a computer that’s why I wanted some one else to simulate the circuit or for some one to tell me if the think at the circuit wud work

author: jhpadjustable
author_rank: Frequent Contributor
timestamp: December 23, 2019, 12:42:20 am
content: But you apparently have a web browser, so you can use this.http://www.falstad.com/circuit/circuitjs.html

author: Ben sage
author_rank: Contributor
timestamp: December 23, 2019, 01:07:19 am
content: Think you vary much

author: Renate
author_rank: Super Contributor
timestamp: December 23, 2019, 01:49:17 pm
content: That schematic shows quite a bit of effort.It looks to be master/slave flip flops, but it's not quite there, I don't think.The set of one flip flop feeding the reset of the previous flip flop makes it seem like you were aiming for a "traveling bit" divide-by-four counter.The cascaded ANDs makes it seem like you were aiming for a binary divide-by-sixteen counter.I tried that web editor on a cell phone, that would drive me insane.You can make master/slave flip flops out of NORs and ANDs.Still, with NANDs being the cultural favorite, using just NANDs seems more recognizable to most people.Here's a toggle flip flop using NANDs.