hybridfree/eevblog-posts huggingface dataset:
unknown diode part number - Page 1
Forum section: electronics / projects

author: ksb
author_rank: Contributor
timestamp: September 16, 2019, 02:31:07 pm
content: Please help me to identify the correct part number or replacement for diode marked as motorola K02 06 86 302

author: Zero999
author_rank: Super Contributor
timestamp: September 16, 2019, 04:19:56 pm
content: It looks suspiciously like a zener diode, going by the case and how it's connected in the circuit, with the anode to what looks like a ground plane and the cathode to a resistor.I take it you're trying to repair something? What does the circuit do? How do you know the diode is faulty? There's no physical sign of damage such as charring. Do you have a schematic? It's possible it's a different component which is bad.

author: MagicSmoker
author_rank: Super Contributor
timestamp: September 16, 2019, 04:49:36 pm
content: It's definitely a zener diode, but it looks like it is part of a crowbar type overvoltage protection circuit in a power supply. Does the anode (eventually) connect to the gate (shorter flag terminal) of the stud-mounted thyristor? If so, the zener voltage will likely be a little higher than the output voltage of the supply.

author: Zero999
author_rank: Super Contributor
timestamp: September 16, 2019, 05:47:16 pm
content: Looking more closely, it's not connected to the ground plane, but another pad. I think MagicSmoker is right. It's going to an SCR and is a overvoltage protection crowbar.

author: ksb
author_rank: Contributor
timestamp: September 23, 2019, 06:29:26 am
content: Its a Spectrum Analyzer power supply. The diode has no reading at all. Seems like open circuit.

author: ksb
author_rank: Contributor
timestamp: October 02, 2019, 06:51:34 am
content: How to find the actual part number?

author: MagicSmoker
author_rank: Super Contributor
timestamp: October 02, 2019, 09:58:45 am
content: The power supply should work without the crowbar. If it isn't then it might be because the crowbar fired and then failed short. So, try removing the thyristor if there is no output but it still draws a heavy current from the mains.P.S. - this belongs in Repair; maybe move it there or ask a mod to.

author: 741
author_rank: Frequent Contributor
timestamp: October 02, 2019, 01:25:20 pm
content: That looks like a Motorola "M". It might be worth establishing the case code, maybe DO204.
Unknown EEprom help - Page 1
Forum section: electronics / projects

author: JerryL
author_rank: Newbie
timestamp: April 26, 2019, 02:18:26 pm
content: This chip is from the toner of a Lexmark MX321 printer toner. The numbers I got from it are H1828553 and I am trying to read from it with an Arduino 2560 but haven't a clue where to start. Anyone help I do know the pinout for the connection between the toner and printer and have it connected already but I do not know the commands yet.

author: coromonadalix
author_rank: Super Contributor
timestamp: April 26, 2019, 02:31:54 pm
content: you want to reset the toner ?on alibaba search : Toner-reset-chip-for-Lexmarknormally on 4 pins pcb toners chips you have to find the +vcc and ground supply lines and with the 2 remaining pins you have to fine the data lines, reset pins etc ... and fit your arduino accordingly

author: JerryL
author_rank: Newbie
timestamp: April 27, 2019, 10:51:23 pm
content: Got that done was just curious as what the chip was I know it is an eeprom and have the arduino 2560 connected now I need to lear the commands to read and write to the chip. ANy help is gretaly appreciated

author: PON
author_rank: Newbie
timestamp: January 03, 2020, 04:07:49 pm
content: Hi.Did U find what kind of chip is, and with what do U search? I'm also verry intersting about this eeprom

author: kjr18
author_rank: Regular Contributor
timestamp: January 04, 2020, 10:14:40 am
content: Are you sure it's an eeprom? I skimmed through alibaba search and I see some toner reset chips boards with eeprom on it, some with two chips (one looks like a memory, second one like some uC), or even some that have two many_pin chips.I guess that yours might be a microcontroller of some sort that has eeprom memory inside and communicates with i2c, or something like that.
Unknown IC - Page 1
Forum section: electronics / projects

author: ResR
author_rank: Regular Contributor
timestamp: April 24, 2021, 11:04:20 pm
content: Found this in a parts bin, has no markings as top got damaged long time ago. Does anyone recognize the mark by this function waveform? It's almost like a quad flip-flop until both inputs on one side are used which makes it dual something.V1/V2/V3/V4 are outputs, S1/S2/S3/S4 are inputs._

author: fcb
author_rank: Super Contributor
timestamp: April 25, 2021, 12:24:37 pm
content: 4013?

author: ResR
author_rank: Regular Contributor
timestamp: April 25, 2021, 08:27:37 pm
content: Maybe, the independent switching of 4 outputs throwed me off-course. I have to test it on breadboard again soon.

author: ResR
author_rank: Regular Contributor
timestamp: May 01, 2021, 07:40:38 pm
content: Thanks for help, it turns out to be just a CD4013, quite amazing how much abuse these chips can live through and still be alive decades later.
unknown IC - Page 1
Forum section: electronics / projects

author: Andrew48
author_rank: Newbie
timestamp: November 10, 2016, 03:25:53 pm
content: Hello,need help to find out what kind of component that is. Does anyone know?was about the year 1991. Is there something newer?

author: strawberry
author_rank: Super Contributor
timestamp: November 10, 2016, 05:32:51 pm
content: http://www.jotrin.com/product/parts/GA_9720B

author: Zero999
author_rank: Super Contributor
timestamp: November 10, 2016, 05:46:54 pm
content: Quote from: strawberry on November 10, 2016, 05:32:51 pmIt won't let you access the datasheet though, unless you have/create an account.

author: Cliff Matthews
author_rank: Unknown
timestamp: November 10, 2016, 11:32:53 pm
content: I get Google results on Gamma Rays and co-incidentally, 9720keV. Maybe it's a bogus marking? This is certainly not like the gold "rad-pack" stuff I saw ages ago at Litton's.

author: Andrew48
author_rank: Newbie
timestamp: November 11, 2016, 09:59:47 am
content: Thanks.Do I have to create an account for the pdf..mmmthere are more two parts I don't know yet. If I could find out these 3 components I could finish my project to renew this circuit in smd 0805gamma 9720 /18pinsga 772 /3pin853 NO8 /3pincould be a voltage regulators or something like that..

author: Gyro
author_rank: Super Contributor
timestamp: November 11, 2016, 10:29:11 am
content: It would be really helpful to have some context - what the board is, where is it used, what does it look like etc. Otherwise it's a but like trying to identify bits of an elephant in a blindfold. Btw, that resistor in the foreground of your second picture looks as if it has been damaged by scraping against something.

author: Andrew48
author_rank: Newbie
timestamp: November 11, 2016, 01:11:02 pm
content: Ok..It's a wireless headphone in very good quality (transmitter)It should be as small as possible on a single board with a squelch.It has no squelch. The reason why I wanted to make a new one

author: tatus1969
author_rank: Super Contributor
timestamp: November 11, 2016, 01:23:08 pm
content: the two 3-pinners are very likely NPN or PNP  BJTs. You can easily test it with a multimeter that has a diode testing mode. I would choose an alternative with enough voltage rating, and good bandwidth (which operating frequency?), and solder them into the original circuit for a test.

author: Andrew48
author_rank: Newbie
timestamp: November 13, 2016, 09:19:41 am
content: Quote from: Andrew48 on November 10, 2016, 03:25:53 pmGA- 9720=BA1404 ?What do you think?

author: MatthewEveritt
author_rank: Unknown
timestamp: November 13, 2016, 10:03:30 am
content: Quote from: Andrew48 on November 11, 2016, 09:59:47 amNope, you need an account to find out that they don't actually have the pdf.(I looked usingbugmenot)
Unknown nixie tube - Page 1
Forum section: electronics / projects

author: lamello
author_rank: Contributor
timestamp: August 15, 2018, 06:11:56 pm
content: Hello,I have bought some nixie tubes, but i can't find some technical information of those nixies.They have 2 lines of codes:MBT109GTTHas someone any information obout these nixies? (Technical info or compatibility with another nixie)?TIA lamelloVerstuurd vanaf mijn GT-I9515 met Tapatalk

author: marshallh
author_rank: Unknown
timestamp: August 15, 2018, 06:16:25 pm
content: Looks like it could be a ZM1000 derivative.In any case, they are all basically the same. Find your 1-2 anode pins, avoid the getter pin, then all the others will be cathodes. Apply 150-180V at 2mA, done.You can probably even find the pinout just from looking through the glass.

author: james_s
author_rank: Super Contributor
timestamp: August 16, 2018, 04:08:35 am
content: Definitely looks like a ZM1000.http://www.tube-tester.com/sites/nixie/dat_arch/ZM1000_ZM1000R.pdf

author: lamello
author_rank: Contributor
timestamp: August 17, 2018, 12:49:24 pm
content: Many thanksNow i can search for some schema's for those pixies.Lamello
unknown old Moto chip GSCR38102PG05 - Page 1
Forum section: electronics / projects

author: uwezi
author_rank: Unknown
timestamp: December 18, 2015, 11:13:15 pm
content: Just out of curiosity...I got a small bag of PLCC-68 chips from a colleague who is cleaning out his office. He did not remember what these were planned for, the chips are obviously unused.Manufacturer: MotorolaDate code: 1987 week 01RYT3050012GSCR38102PG05Google gave me the usual suppliers with old stock and one link claiming it to be an 8Mbit SRAM, which seems unlikely, since we just barely had 1 Mbit DRAM chips on the market back in 1987...Does anyone have a clue to what these chips might have been used for?
Unknown part from a running LED light display - Page 1
Forum section: electronics / projects

author: DMartens
author_rank: Contributor
timestamp: July 27, 2021, 08:32:37 am
content: Have an old (1980's) LED display sign, made by Text Lite, model MM300, typically used in shops windows to display promo messages etc.Modified the unit and replaced the original microcontroller, RAM etc. by an Arduino. All is working fine but it has an unknown component in it that mystifies me and that I would like to identify.It is 30mmx30mm square and 16 mm high. No text on top. Text on bottom has pin numbers 1 through 10 around the perimeter but only pins 1, 5 and 8 are physically present. It also has the text "29-1" and "bfi". Couldn't find anything on google text search, nor on google image search.Anyone got any ideas what this is? Pictures of component and MM300 attached.

author: capt bullshot
author_rank: Super Contributor
timestamp: July 27, 2021, 09:32:17 am
content: My guess:A potted toroidal inductor - not sure what the third pin is, maybe just electrically not connected and used for mechanical stability only.

author: Terry Bites
author_rank: Super Contributor
timestamp: July 27, 2021, 01:04:22 pm
content: Could be an evil autotransformer..

author: ajb
author_rank: Super Contributor
timestamp: July 27, 2021, 03:11:40 pm
content: What was it connected to in circuit?These days that's a common form factor for things like DC-DC converter modules, a little plastic box that a PCB etc gets dropped into and then filled with potting compound. But at that age, you couldn't fit all that much complexity in there just due to the components that were available. Could be just about anything, but only having three pins limits the options a fair bit. The potting boxes are generic and can be bought off the shelf, hence ten pin positions with only three loaded.

author: StillTrying
author_rank: Super Contributor
timestamp: July 27, 2021, 04:30:51 pm
content: I don't know what it is, it does look like one of these early attempts at a DC-DC converter.https://www.acalbfi.com/uk/Power-supplies/DC-DC/PCB-mounted/c/CAT-13-03-05

author: DMartens
author_rank: Contributor
timestamp: January 03, 2022, 11:05:13 am
content: Thank you all for your replies and sorry for my late response ... initially I also thought it was a DC-DC converter but the number of pins does not seem to make sense as I would expect there to be at least 4: 2 for input and 2 for output ... but the component has only 3 pins populate so a toroidal inductor as suggested by Capt Bullshot is the most likely.
Unknown part from AliExpress - Page 1
Forum section: electronics / projects

author: Merlin_Shaw
author_rank: Newbie
timestamp: June 30, 2021, 11:54:20 pm
content: I ordered SN74LVC1G125 C255 from AliExpress but got something different.It looks to be the same size, but has 6 pins instead of the needed 5 pins.The markings show R6 76t which I googled and couldn't find anything.Any help would be appreciated, I have contacted the AliExpress seller but was curious.

author: amyk
author_rank: Super Contributor
timestamp: July 01, 2021, 12:20:18 am
content: BCM847DSYou can find those on Ali too... so see if you got more or less than what you paid for:https://www.aliexpress.com/item/32868729616.html
Unknown Schematic Symbol - Page 1
Forum section: electronics / projects

author: Gibborim
author_rank: Newbie
timestamp: July 28, 2016, 02:16:29 am
content: I'm looking over a schematic and I don't know what this symbol means. It seems to be the voltage clamp on a USB data line. Can anyone tell me what it is?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: July 28, 2016, 02:48:49 am
content: https://en.wikipedia.org/wiki/Varistor

author: jonovid
author_rank: Super Contributor
timestamp: August 25, 2016, 02:59:06 am
content: thermal fuse , maybe need to see more of the circuit.

author: Pjotr
author_rank: Frequent Contributor
timestamp: August 25, 2016, 07:13:38 am
content: It is simply a VDR, a voltage dependant resistor. De dependence can be positive or negative, usually indicated bij a "+" or "-" sign near the diagonal line. In general a depndant resistor is represented by a diagonal line through the resitor symbol. What the dependence is can differ, can be voltage: V, temperature: T, light: L etc.The example given has a wrong symbol. De numbers given actually specifies a zener diode or a "Transzorb" of 5V. Although its behaviour is voltage dependant it is not the same thing as a VDR.
Unknown secundary peaks in motor control PWM signal. - Page 1
Forum section: electronics / projects

author: E
author_rank: Contributor
timestamp: May 11, 2013, 05:12:50 pm
content: Hey guys,I'm currently working on a diy motor controller for brushless motors for fun. I'm trying to use Jianwen Shao's method (http://scholar.lib.vt.edu/theses/available/etd-09152003-171904/unrestricted/T.pdf) of measuring the rotor position on the third coil while the driving PWM signal is low.I'm sending a PWM signal to the FAN7888 motor driver (http://www.fairchildsemi.com/ds/FA/FAN7888.pdf) and measure the voltage of the floating coil behind a 10kOhm resistor with an Atmel microcontroller.It's working rather neat so far, but I ran into something weird that I can't explain: shortly before the PWM on the high MOSFET of the active coil rises, I get an unexpected edge going up about 2V before the PWM going up to 20V. It's a rather sharp edge modulated onto the voltage induced by the stators permanent magnets. (see pictures) These secondary peaks mess up my measurements of the rotor position.The measured point is the floating coil directly, connected to the lower side of the motor drivers charge pump, the drain of the lower MOSFET, the source of the higher MOSFET and to the microcontroller via a 10k resistor. (And obviously the other two coils in the motor.)Is this caused by the charge pump or am I not getting something? As you can see from the images, the width of those secondary peaks varies. Also with (much) higher RPM they luckily disappear.Thanks for any help,E

author: Paul Price
author_rank: Super Contributor
timestamp: May 15, 2013, 07:20:13 pm
content: No, the waveform is correct, you are simply seeing the voltage across the diode float up to the output voltage level after the catch diode has completely discharged the inductor.

author: Paul Price
author_rank: Super Contributor
timestamp: May 15, 2013, 09:48:43 pm
content: Also be aware of the very poor recovery time of the vertical digitizing circuitry to overrange signals, and thus any waveform you see that in peak amplitudes exceeds the top or bottom graticule line, will be severely distorted, unlike the correct pulse shapes and amplitudes shown a cheap old analog oscilloscope.
Unknown SOT-23 devices, lost cause? - Page 1
Forum section: electronics / projects

author: PeterFW
author_rank: Frequent Contributor
timestamp: March 18, 2015, 01:21:37 am
content: Hello!Most likely this is futile but i will try, google dit not help me, i got a couple of SOT-23 parts:The only things to measure i have are a multimeter and a DSO,my meter says:GHMH9: 2 <> 3 shortedH9LF4: 2 <> 3 shortedS7W5: 2 <> 3 shorted and anode on pin 1, kathode pin 2 with 0,51V UFThe others do not show annything, before i try to determine by try and error what they might be, i thought i ask here.Annyone seen one of these before, i can not remember what they are.They were in an order from a local supplyer, years ago.They must be different types of FETs, two of em may be JFETs.Greetings,Peter

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 18, 2015, 03:47:13 am
content: E4L = BAT54http://www.s-manuals.com/pdf/datasheet/b/a/bat54_utc.pdfS7W = maybe BF511? Something by Rohm? Not sure.SA = but, that doesn't look like an "A"... not sure what that is.Can't find anything on the HMHS or H9LF4.I probably shouldn't transcribe these numbers because now this thread will be the only thing that ever shows up in searches for those parts.http://xkcd.com/979/Tim

author: Macbeth
author_rank: Super Contributor
timestamp: March 18, 2015, 03:50:19 am
content: SA could beBSS123 MOSFET
unknown transistor ? - Page 1
Forum section: electronics / projects

author: spetros
author_rank: Contributor
timestamp: November 19, 2024, 10:45:21 am
content: Hello .I am trying to identify the transistor? at the picture ( AEW ,6GA).I haven't found any details for it yet.Can you help me about it ?Thank you

author: bostonman
author_rank: Super Contributor
timestamp: November 19, 2024, 02:25:15 pm
content: Try this site for your search:https://smd.yooneed.one/

author: jpanhalt
author_rank: Super Contributor
timestamp: November 19, 2024, 03:13:15 pm
content: I did that earlier and came up with a 2N7636GA, which is a silicon carbide, high-voltage N-JFET (obsolete) in a TO-276 leadless package.Link:https://alltransistors.com/mosfet/transistor.php?transistor=45402Years ago, I marked that as my best SMD site. Today, it is infested with ads and pop-up links. Be careful. I did not find a datasheet on Mouser or Digikey, but it is on the link. The circuit should help decide whether that is correct.EDIT: Here's the package from Microchip. Those dimensions should help:https://ww1.microchip.com/downloads/aemDocuments/documents/package-outline-drawings/c04-25534a.pdf

author: bostonman
author_rank: Super Contributor
timestamp: November 19, 2024, 03:33:00 pm
content: QuoteYou searched on the site I suggested (which I got from someone on here in another post)?When I did the search, I found regulators. I'm just curious, what did you search for?

author: jpanhalt
author_rank: Super Contributor
timestamp: November 19, 2024, 04:07:01 pm
content: The site you posted is also in my list of standard SMD sites. I searched on the linked to site first. After I saw that transistor's ratings, I searched other sites to cross check. They all indicated voltage regulators. Since the last digit of the 2N and GA aligned ("6GA"), I decided to wait and to see if more information came forth.Here is my standard SMD code search list:1)http://www.marsport.org.uk/smd/mainframe.htm2)https://alltransistors.com/smd-search.php?search=y1(labeled "best")3)https://www.sos.sk/pdf/SMD_Catalog.pdf4)https://smd.yooneed.one/5)http://caxapa.ru/thumbs/588912/smd-codes.pdfI also have the "SMD Codebook" but no link to it. As mentioned, the all transistors site has gone a bit too commercial. I also assumed there would not be 2 voltage regulators with Q# identifiers, and two transistors made more sense.

author: bostonman
author_rank: Super Contributor
timestamp: November 20, 2024, 02:46:25 am
content: QuoteDo you mean an actual book or a website? One link you provided, and I also found through Google when I searched for "SMD Codebook" was titled as such.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 20, 2024, 05:06:08 am
content: It was a old link I downloaded as a pdf and didn't save its URL. My version is 80 pages. This link appears to be to an updated site with the same thing. It is now 85 pages with advertising:https://www.sos.sk/pdf/SMD_Catalog.pdf
Unloading/selling ADAU1451 DSP's - where? - Page 1
Forum section: electronics / projects

author: jrs45
author_rank: Regular Contributor
timestamp: March 01, 2022, 03:24:31 pm
content: We have around 1000 of these parts that we purchased for a new design, but because we can't expect to get more anytime soon, we've shelved it. Brand new, still factory sealed.We'd like to sell them, clearly they are in demand. Where should this be done? I'm not crazy about ebay but I don't know of other places to do this.
Unlock a box remotely? - Page 1
Forum section: electronics / projects

author: Aerobyrd93
author_rank: Contributor
timestamp: November 29, 2015, 10:15:49 pm
content: Okay, so my friend and I have a game we are making. The game calls for a box which could be at his house in one state, and be unlocked by me in my house in another state at will. Once finished, the box would then be closed again at my friend's house, who would then be unable to open it until unlocked by me again. Can anyone offer guidance as to how one would go about doing this?I hope this is clear, really it just comes down to being able to provide a 1/0 input to a device at a distance as frugally and reliably as possible. Both locations will have both wifi and router access, whichever is easiest to deal with.Thanks!

author: Muttley Snickers
author_rank: Unknown
timestamp: November 29, 2015, 10:24:45 pm
content: If the remote site has a telephone then DTMF is a valid option and if there is an existing security alarm system at the premises then this could be utilised easily depending on the particular system, on most systems an output can be turned on or off by a remote connection via the telephone network including PSTN, GSM and GPRS.Radio CTCSS tones could also be used again depending on the distance involved and as mentioned below a particular tone could enable or disable an output, plenty of options including WAN.

author: SpidersWeb
author_rank: Unknown
timestamp: November 29, 2015, 10:49:53 pm
content: I was thinking Arduino with Wifi shield or similar.I can't offer much more than that, would just be the first thing I'd google.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 29, 2015, 10:57:23 pm
content: What about a tone detector and just play the tone over the phone? Not very secure but as it's just a game, I don't think security is particularly high on the list.

author: mtdoc
author_rank: Super Contributor
timestamp: November 30, 2015, 01:19:06 am
content: ESP 8266 and a small servo motor for the lock. I think Dave had an item on a recent mailbag that used a small servo to lock a box.Or instead of the servo to do the locking - you could use one ofthese small push-pull solenoids

author: boffin
author_rank: Unknown
timestamp: November 30, 2015, 08:19:19 am
content: Electric Imp. Dead easy to set up. Simple web request from one side to unlock

author: Delta
author_rank: Super Contributor
timestamp: November 30, 2015, 12:25:10 pm
content: This all sounds very kinky...!

author: Jeroen3
author_rank: Super Contributor
timestamp: November 30, 2015, 12:56:01 pm
content: You can use two standard cellular controlled relay boxes. These you can program to act on inputs to text the other box.Or diy with a Particle Electron (former spark core).
Unlocking cheap GPS tracking device FMT200  - Page 1
Forum section: electronics / projects

author: Jackster
author_rank: Frequent Contributor
timestamp: April 27, 2025, 10:18:16 pm
content: Picked up this cheap GPS tracking unit from Amazon.https://www.amazon.co.uk/dp/B0CY5QQBYZ?tag=a002ee-21Looks to be an upgraded version of the FMT100 by Teltonika but there is no mention of the FMT200 on their website.It also states 9-90V input on the FMT100 while all of Teltonika's devices are 10-30v? I am wondering if this is a Chinese clone.I have inserted my own IoT SIM into it and it still reports back to the seller's tracking server, so there is no locking down of what SIM cards you can use.I have tried to send it commands as per the documentation but I do not get a reply from the device.https://wiki.teltonika-gps.com/view/FMT100_SMS/GPRS_CommandsAnyone here got any ideas?There looks to be USB pints on the PCB. I might give those a go and see if it will come up as a device.But other than that, I am out of ideas.
Unobtainium "Wirefy" crimp dies actually made by Hsun Wang. Where to buy? - Page 1
Forum section: electronics / projects

author: incf
author_rank: Frequent Contributor
timestamp: April 13, 2025, 06:21:12 pm
content: I recently bought a "Wirefy" quick change crimp kit (it included rare die for miniature/small gauge crimp terminals). It worked well, price was right, but there were a few models of die that the kit didn't come with and were out of stock or not listed for individual sale.Some searching yielded source . Apparently Wirefy is actual made by Hsun Wang. It mentioned the existence of a compatible RJ45 crimp die  and linked to the manufacturers catalog .I would like help identifying where I can buy the following models of Wifefy/Hsun Wang crimp die (maybe there is a German brand [or some other country] that is just an imported Hsun Wang or compatible)Crimp Die "D" for metal ferrules(Generic?) Crimp die for RJ45I've searched Aliexpress, Amazon, and Ebay. But perhaps with the wrong terms.Australian retailer Jaycar appears to sell the RJ45 version. Not sure they would ship to the US.I have not found any retailers/brands that sell ferrule die model "D".https://www.hsunwang.com/product/category/jawshttps://www.reddit.com/r/HomeNetworking/comments/11vecw5/comment/jvf2e0d/https://www.jaycar.com.au/quick-change-crimp-tool-die-rj45-8p/p/TH2002edit: I did find a sketchy "wozobuy" brand listing on Aliexpress. Not sure I trust it.

author: ajb
author_rank: Super Contributor
timestamp: April 13, 2025, 08:25:10 pm
content: Those look like the tools sold as "Snap-n-Crimp" here:https://www.ferrulesdirect.com/collections/snap-n-crimp-tools, and they do have dies for RJ45/8P8C connectors.I'm sure neither of these are the originator of that specific design. Just doing an image search for "quick change crimp tool" brings up a ton of results in that style of die under a bunch of different brand names.EDIT: actually on closer inspection, the dies on Ferrules Direct appear to have the same letter/number designations as your image, so that may be exactly what they're selling.

author: incf
author_rank: Frequent Contributor
timestamp: April 13, 2025, 08:51:07 pm
content: Perfect!

author: incf
author_rank: Frequent Contributor
timestamp: April 13, 2025, 09:11:31 pm
content: Since this thread has been so fruitful I'll post a followup question.Where can I locate either of the following models:10" of crimp tool?*edit: ferrules direct also has the 10" (missed it when I posted)9" parallel action crimp tool?**made by Hsun Wang and rebrandedIt's not clear to me that there really is much different between the 8.7" and the 10".It is also not clear to me what advantage the parallel action "pro" crimp tool has. Are there specific dies for this series of tools that benefit from parallel movement?
Unofficial OSHPark Turnaround Times for 4 layer boards - Page 1
Forum section: electronics / projects

author: ShaunAndFRED
author_rank: Contributor
timestamp: October 29, 2013, 11:46:36 pm
content: After listening to Amp Hour #149 Laen from OSHpark.com, it sounded like the delivery time was starting to speed up as more and more people used the service. I was just wondering what people were seeing for delivery times.

author: marshallh
author_rank: Unknown
timestamp: October 30, 2013, 02:23:19 am
content: About 2 weeks usually, generally he does 2 batches per month.The problem as it stands is he rotates between 3-4 different fabs, and I along with some others keep getting plating problems, drill mishaps, etc...Laen is pretty good at responding but nonetheless we keep having problems. I'm trialling another fab because of it.This is all for 4layer of course.

author: Laen
author_rank: Newbie
timestamp: November 06, 2013, 07:53:21 am
content: I have actual data on this!The tempo I'm going for right now is two panels a month, with a 2 week turn time on them. That should mean that if you order at any random moment, you should expect your boards to ship in about 21 days. If you time it really well, it can be as low as 8 days, but that's difficult. Especially since panels can fill up and go to the fab early.Anyway, the stats!Over the past 9 months:Minimum time from ordering to shipping: 8.00 days. That's pretty much the minimum possible time. Only 2% of orders got this, and only 5% hit 9 days.25% of orders were shipped within 14.00 days of ordering.Median time from ordering to shipping: 17 days.Mean time from ordering to shipping: 18.14 days.75% of orders shipped by 21.75 days. 95th percentile was 29 days.Not great, but as it grows in popularity, I'll be able to order panels more often, which will drive that time down.In fact... If I only run the query on the last 4 four layer panels, the mean drops to 16.86 days. So it's getting there slowly.As marshall said, there were definitely some quality issues on the 4 layer panels when I first switched to FR408. Mostly things like poor drill registration, and hole sizes being slightly out of spec. I worked with the fab to make sure our expectations matched and found a couple of mismatches (they thought they were allowed a 3.5 mil hole size variance instead of 2.5 mils, and a 3 mil registration tolerance instead of a 2 mil) which have been taken care of. My test boards from the past 3 panels has been clean so I _think_ we're now pretty good.-Laen
Unpowered USB esd protection - Page 1
Forum section: electronics / projects

author: zitt
author_rank: Regular Contributor
timestamp: August 22, 2019, 03:17:11 am
content: My computer desk is a mess... I'm always loosing USB memory sticks because I don't really have a way to storing them. They tend to migrate everywhere.. multiply... get lost... fall to the floor - get kicked under the desk... repeat... rinse. You get the idea.I want to make a perm home for these little buggers so:1) I can easily find them.2) organize them3) store themBut I don't want to just throw them in a drawer - because drawers tend to collect other things.YEARs ago; I designed my owncomputer caseandstand out of square tubing:I've decided I want to mount the USB stick in vertical USB-A connectors to a PCB made at OSHPark. IE have them mount just like they would be in a usb port. It would be attached used a 3DPrinted bracket at a 45degree angle to the front of the computer stand.Now obviously; I can just mount the connector as is with no electrical connections... but where's the fun in that?I'm thinking I want to at least connect the grounds of the USB ports to a ground point on the nickel plated stand. I obviously don't want to run power to the +5V line of the connector; but should I consider ESD protection diodes? What about on the D+/D- lines?I'm specifically looking at TI's app note:http://www.ti.com/lit/sg/sszb130c/sszb130c.pdfon page 13 as a reference.Obviously - anything I do is way over kill at this point; but was wondering what you guys thought about ESD protection? Do it? if so; why? if not; other than costs - why not?Should I put a large-ish resistor from +V to ground to bleed off any charged caps in the devices?

author: wraper
author_rank: Unknown
timestamp: August 22, 2019, 03:24:49 am
content: QuoteWorst idea you could come up with. Grounding them won't make things better, only worse because with it appears path for significant capacitance/ discharge current. Like discharge path from human holding USB stick, through it and to ground. Also data pins are recessed, so there is little reason to bother about them during storage. Plugging them into connectors will increase connector wear. And if you do so, either leave all pins floating or just connect all of them together (within single connector) but don't connect to anything else.QuoteWhy would you use diodes when there is no voltage/signal to pass?
Unregulated lm2596 - Page 1
Forum section: electronics / projects

author: conducteur
author_rank: Regular Contributor
timestamp: August 20, 2019, 02:32:25 pm
content: I have troubles with my lm2596 power supply. I have this circuit on a pcb and it doesn’t work. Tried different inductors, two types of diodes,... I soldered the components together with a few wires to know if there’s a problem with my pcb... but the output voltage is also just below the supply voltage...Output C = 680uF en load =39 OHM

author: thinkfat
author_rank: Unknown
timestamp: August 20, 2019, 03:55:25 pm
content: You mixed up pin 1 and 2.EDIT: but it's really hard to see with the tangled mess you have created there.

author: mariush
author_rank: Super Contributor
timestamp: August 20, 2019, 04:26:03 pm
content: you're dealing with a switching power supply IC, running at 50-100kHz ... at the very least put it on a prototyping board.It won't work right with wires floating like that.

author: conducteur
author_rank: Regular Contributor
timestamp: August 20, 2019, 05:46:12 pm
content: Thank you very much thinkfat! I made that mistake when creating the symbol for this part in EAGLE and used my schematic as a reference (bad idea when you're troubleshooting such problems).... Could search this circuit for hours to find that one!Now I have to find out if I can mod the PCB...
Unsolder a webcam-sensor to extend connection to board - Page 1
Forum section: electronics / projects

author: andreasso
author_rank: Newbie
timestamp: May 01, 2020, 09:15:36 am
content: Hello everybody,i would like to make a webcam that is so small (6x6 mm) that i can attach it on a larger screen (e.g. with a removable adhesive) in the picture without it interfering greatly with e.g. 1to1 video conferencing. Since every webcam I have found so far is quite big, including the electronics, at a usable resolution of 2 MP, I had the idea to take the webcam from an old laptop, which has a small sensor. My idea is to unsolder the sensor from the board and to provide it with a thin cable that doesn't disturb in a bigger picture. That way i get a really small thing i can put on the screen and the rest of the hardware I can attach to the edge of the screen.I can then control the webcam via USB (description e.g. here)Can it work like this? Is it feasible to unsolder a mini-cam and then to "extend" it form the minipins with a cable to reconnect it to the board? Does anyone have an assessment of whether this can work? Interference with the new connection?I would be very thankfull for suggestions and asessments.In case you are wondering what this is all about: I work a lot with 1to1 videoconf and it would be very helpful for my work if I could look into people's eyes in a way that they can perceive it and I can see their face at the same time.Best regards, Andreas

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 01, 2020, 01:23:37 pm
content: Look up "borescope camera" for really small cameras on the end of a USB cable.

author: andreasso
author_rank: Newbie
timestamp: May 02, 2020, 10:55:46 am
content: Thanks, I have looked at this option too, but while the diameter of such cams would be sufficiently small, their length is still to much.The camera module without the circuit board would be a good fit, about 5x5x4 mm. Ideally I would have the board somewhere at the edge of the screen and the camera module would be connected with very thin cables to the it.Could that work?Thanks in advance for your ideas!
Unstable current limiting - Page 1
Forum section: electronics / projects

author: jtruc34
author_rank: Regular Contributor
timestamp: March 06, 2023, 06:05:54 pm
content: Hi,Attached below is a schematic of a kind of regulated 15V power supply (don't mind the use of the LM2931, it only serves as a low drop-out voltage reference and as a overtemperature limit). I added a current limiting circuit for overcurrent protection (mainly for Q5 and Q7).If C7 is not present, it works as intended, but I want to allow for short current spikes which wouldn't damage Q5 and Q7. I thus thought of slowing down the feedback loop by adding R22 and C7. If I do that, the circuit becomes unstable (current oscillates between 3 and 10A for a load of 1.5 Ohms).Before I do the full small signal loop analysis to see where the unstability is coming from and where to put R22/C7 instead, is there an obvious way to do what I'm trying to do while staying stable?Thanks

author: Vovk_Z
author_rank: Super Contributor
timestamp: March 06, 2023, 06:40:24 pm
content: Is there really a need to pass current spikes through? What if they will be smoothed by a current limiting circuit?

author: Benta
author_rank: Super Contributor
timestamp: March 06, 2023, 08:00:15 pm
content: R12 seems very high to me, 10k...22k would be closer to the mark.C7 adds a pole to your current feedback loop. What that does to stability is anyone's guess. I strongly suggest a simulation run.

author: jtruc34
author_rank: Regular Contributor
timestamp: March 06, 2023, 08:40:43 pm
content: Quote from: Vovk_Z on March 06, 2023, 06:40:24 pmIt will serve for audio, and it may require big current spikes. They could be bypassed by C2 anyway, but I'd prefer to not rely on it.Quote from: Benta on March 06, 2023, 08:00:15 pmWhy do you think so? 220k is sufficiently low to fully saturate Q6. BC546B's have a minimum current gain of 200. Do you suggest lowering it to discharge Q8 gate capacitance more quickly? I don't particularly need a fast response, quite the opposite. Plus decreasing R12 would mean higher loop gain and potentially less stability.Quote from: Benta on March 06, 2023, 08:00:15 pmAdding that pole is kind of the goal, but maybe in a more controled manner. What do you suggest to look at in the simulation?Thank you both for your help
Unuseable mobile phone screens - Page 1
Forum section: electronics / projects

author: moffy
author_rank: Super Contributor
timestamp: May 21, 2024, 09:23:37 am
content: I am replacing the screen on an older Motorola One Macro phone, and for $17 I get this fantastic display which unfortunately can't be used in any projects because there is no information available. It seems such a pity that such screens are inaccessible, such a lost resource and perhaps opportunity. There are a couple of older projects, one for the Iphone 4 but that's about all, a pity.

author: amyk
author_rank: Super Contributor
timestamp: May 22, 2024, 12:39:22 am
content: They are almost all MIPI.

author: moffy
author_rank: Super Contributor
timestamp: May 22, 2024, 02:13:25 am
content: Quote from: amyk on May 22, 2024, 12:39:22 amYeah, from what little I know of LCDs, they require specific programming instructions/sequences that are unique to each screen and covered by NDAs, the lack of that data makes them unusable without significant reverse engineering effort. Please correct me if I am wrong I would love for them to be usable.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 22, 2024, 03:44:25 am
content: Cheapest way to reuse one is to reuse the entire phone. Learn a bit of app development and connect it to your project over USB.
Unusual 74HC595 circuit design - Page 1
Forum section: electronics / projects

author: karan279
author_rank: Newbie
timestamp: October 07, 2013, 06:29:02 pm
content: Hi all ,here is a circuit i traced from a machine spare part for Looming , so it has this 74hc595 with its 2 pins the storage clock and shift clock connected via a resistor and cap , and all i can think of is maybe its done to save a pin , but could anyone tell who may have worked on such a design and how i could probably test it .

author: dannyf
author_rank: Super Contributor
timestamp: October 07, 2013, 06:50:11 pm
content: QuoteYou are right. It is one of the oldest tricks in the book: short pulses will trigger one pin and low pulses another.In the extreme, you could trigger a shift register like HC595/164 with one single pin.

author: karan279
author_rank: Newbie
timestamp: October 07, 2013, 07:14:59 pm
content: so i guess short pulses should trigger both the clocks

author: dannyf
author_rank: Super Contributor
timestamp: October 07, 2013, 07:21:45 pm
content: Short pulses will trigger the one it is directly connected to. Long pulses will trigger both.It relies on the rc constant of the r/c network: quick pulses doesn't change the voltage on the capacitor.
Unusual capacitor symbol - Page 1
Forum section: electronics / projects

author: DMartens
author_rank: Contributor
timestamp: July 31, 2024, 01:26:09 pm
content: What kind of capacitors are those highlighted in the attachment? They are 220pF but have different-from-usual symbol? Are they a special kind? How many leads would I expect them to have? BTW ... schematic is from a satellite receiving front-end from the 1980's.

author: selcuk
author_rank: Frequent Contributor
timestamp: July 31, 2024, 01:31:06 pm
content: Feed through capacitors. A special kind for filtering noise for example.https://www.digikey.com/en/products/filter/feed-through-capacitors/845

author: RoGeorge
author_rank: Super Contributor
timestamp: July 31, 2024, 01:35:13 pm
content: Those are feed-through capacitors, they are used to pass wires through enclosure walls and/or through the metal shielding cans of a circuit.https://en.wikipedia.org/wiki/Feedthroughhttps://www.utmel.com/blog/categories/capacitors/what-is-feedthrough-capacitor
Unusual Li-ion cell size - Page 1
Forum section: electronics / projects

author: Tangent_Tracker
author_rank: Regular Contributor
timestamp: June 13, 2022, 08:01:34 am
content: So I found sound Li-ion cells in a laptop battery that measure 16.7mm x 42.3mm. They are all dead, and I would like some in those dimensions for a project, but I am not able to find any.Has anyone got any ideas as to what to look for? If you round the numbers up you get something like 17420...I guess these are probably OEM with little demand..
Unusual photodiode amplifier - Page 1
Forum section: electronics / projects

author: JimRemington
author_rank: Regular Contributor
timestamp: November 26, 2022, 06:58:42 pm
content: Hi, All:I was reverse-engineering a photodiode amplifier circuit in a consumer appliance and came across a circuit that I had not seen before. The device measures grey levels using a pulsed (25 kHz) IR LED for illumination of the surface, and a reverse biased IR photodiode with a 100K load as the input to the amplifier. The op amp is an LM2902.I've triple checked the circuit and all the values, and am wondering about several features of the design: the 10K load on the op amp, why the photodiode is capacitively coupled, etc. This design would never have occurred to me, so insight would be appreciated! LTSpice .asc file appended, where I have simulated the photodiode output & load resistor with a pulsed voltage source in series with 50K.

author: MasterT
author_rank: Frequent Contributor
timestamp: November 26, 2022, 09:39:25 pm
content: No bias current path, check circuits - there is a mistake.

author: Andy Watson
author_rank: Super Contributor
timestamp: November 26, 2022, 10:27:45 pm
content: Quote from: JimRemington on November 26, 2022, 06:58:42 pmEasy stuff first - it is AC coupled such that it can ignore the ambient light level. It should just respond to the 25kHz IR illumination.Are you sure that you have all the connections? I think the junction of R2 and C2 will be connected to ground, or another reference. If that is the case, then the 10k resistor on the output is to isolate op-amp from the capacitive loading of C2, and also forms a first order low-pass filter.

author: TimFox
author_rank: Super Contributor
timestamp: November 26, 2022, 11:15:22 pm
content: You still need somewhere for the DC value of the photocurrent to go, even though you don't want your circuit to respond to it.For example, you could complete the biased or unbiased diode circuit with a resistor and couple the voltage across that resistor through a capacitor to your amplifier.

author: JimRemington
author_rank: Regular Contributor
timestamp: November 26, 2022, 11:21:06 pm
content: Good catch on the missing R2/C2 ground connection. Now the circuit makes perfect sense, thanks!
Unusual wire connection on USB-3 Type-C plug.  - Page 1
Forum section: electronics / projects

author: ra.hulk
author_rank: Newbie
timestamp: October 13, 2025, 01:46:10 pm
content: I have done a teardown of usb C plug of a usb to ethernet adapter just out of curiosity and found that USB-SS connections are done in a unusual manner. They have used TX+/- and D+/- from one row/side and RX+/- from other side. From what I have gathered by watching teardowns online that RX and TX diff pairs used are always from one row/side (attachment 3). I have designed with USB-3.1 SS signals before with usb C connector and there I had to use a multiplexer to route the signal to the host. MUX decides the orientation based on CC pins and routes the SS signal through it to the host. Now in this condition with SS signals used from either side, how to signals go to the host and vice-versa? MUX will not do switching based on traffic, i guess. This is not from a USB-C cables with type-C on both ends, it has RJ-45 on one end and USB 3.0 Type-C on other(attachment 4). I have worked with some Qualcomm SOMs and they breakout all 4 pairs of USB-3.x data pairs outside, maybe this is not meant to be used with MUXs on USB type-C connectors?

author: wraper
author_rank: Unknown
timestamp: October 13, 2025, 02:03:22 pm
content: TX and RX are on the opposide sides. Thunderbolt cable uses all of the differential pairs available.

author: Chalcogenide
author_rank: Regular Contributor
timestamp: October 13, 2025, 02:09:36 pm
content: For a "male" device using USB 3.0 you only need to use one pair each of SS TX/RX lines, which are either the TX1+-/RX1+- or TX2+-/RX2+-. On a type-c port, the TX1 and RX1 pairs are "on top of each other", i.e. on directly opposing pins; the same, symmetrically, RX2/TX2. Thus, the routing on the ethernet adapter looks correct.Your counter-example of a thunderbolt cable is not a good one, because Thunderbolt generally uses all 4 SS pairs.