hybridfree/eevblog-posts huggingface dataset:
What is this component? - Page 1
Forum section: electronics / beginners

author: TheGlassesGeek
author_rank: Newbie
timestamp: May 21, 2015, 07:59:13 am
content: I wass working on arduino and found this in a scematic. do any of you know what this is? I searched for it but I got no results.

author: German_EE
author_rank: Super Contributor
timestamp: May 21, 2015, 08:13:44 am
content: I'm guessing that it's an incorrectly drawn FET.

author: Warhawk
author_rank: Frequent Contributor
timestamp: May 21, 2015, 08:28:14 am
content: This is P - MOS (FET). These simplified schematic symbols are usually used in microelectronics designs.There is nothing wrong with it:https://www.intersil.com/en/products/amplifiers-and-buffers/all-amplifiers/amplifiers/ICL7611.html

author: Warhawk
author_rank: Frequent Contributor
timestamp: May 21, 2015, 08:41:24 am
content: The magic formula for google image search is "CMOS" design.http://cmosedu.com/cmos1/bad_design/bad_design7/bad_design_7.htmAnd why there is no marking for a source or drain ? Well, in theory FET structure is symmetric and will work both ways if you take care of substrate (body) bias.http://www.circuitstoday.com/jfet-and-mosfet-comparison

author: mcinque
author_rank: Unknown
timestamp: May 21, 2015, 11:35:33 am
content: Why some would connect a DS18B20 with GND and VDD to ground? What I am missing?

author: Warhawk
author_rank: Frequent Contributor
timestamp: May 21, 2015, 11:47:07 am
content: Quote from: mcinque on May 21, 2015, 11:35:33 amYou eagle eye !

author: PA0PBZ
author_rank: Super Contributor
timestamp: May 21, 2015, 11:56:57 am
content: Quote from: mcinque on May 21, 2015, 11:35:33 amVDD:Optional VDD. VDD must be grounded for operation in parasite power mode.

author: mcinque
author_rank: Unknown
timestamp: May 21, 2015, 11:59:13 am
content: hmm.. parasitic power mode, thank you!
What is this component? 8H or H8 on it, white layered rectangle 2x2mm, 2 pins - Page 1
Forum section: electronics / beginners

author: dusan
author_rank: Regular Contributor
timestamp: November 12, 2024, 09:49:28 am
content: What is this component? 8H or H8 on it, white layered rectangle 2x2mm, 2 pins. I think I see layers inside that white part.

author: u666sa
author_rank: Frequent Contributor
timestamp: November 12, 2024, 11:09:25 am
content: Looks like a fuse

author: Harry_22
author_rank: Frequent Contributor
timestamp: November 12, 2024, 12:30:46 pm
content: Quote from: dusan on November 12, 2024, 09:49:28 amSimilar layers?

author: dusan
author_rank: Regular Contributor
timestamp: November 12, 2024, 08:28:10 pm
content: No, more like 5 opaque white layers.
What is this component? Three leads and a "332" label. Voltage regulator? - Page 1
Forum section: electronics / beginners

author: davidhilsabeck
author_rank: Newbie
timestamp: May 11, 2024, 03:29:35 am
content: I don't know what this device does. The picture tells you everything I know. I have several hundred, so knowing will save them from the trash.

author: Kim Christensen
author_rank: Super Contributor
timestamp: May 11, 2024, 04:00:43 am
content: Case style reminds me of a Hall Effect sensor...

author: pcprogrammer
author_rank: Super Contributor
timestamp: May 11, 2024, 06:42:39 am
content: Quote from: Kim Christensen on May 11, 2024, 04:00:43 amThat is what sprung to my mind too,

author: Gyro
author_rank: Super Contributor
timestamp: May 11, 2024, 09:51:55 am
content: Looking at the number on the die, it might be distant relation of this family...https://uk.farnell.com/tt-electronics-optek-technology/ohs3020u/ic-hall-effect-switch-3020-sil/dp/1202503

author: shapirus
author_rank: Super Contributor
timestamp: May 11, 2024, 10:21:07 am
content: Now, THAT is how you ask a "what is this component" question.Hats off!

author: amyk
author_rank: Super Contributor
timestamp: May 13, 2024, 02:35:41 am
content: My guess is something from Unisonic based on the UT marking.

author: davidhilsabeck
author_rank: Newbie
timestamp: May 13, 2024, 05:00:00 pm
content: Thank you everyone for the input. I will see if I can get one to behave like a hall effect sensor this weekend. I'll keep you posted.

author: srb1954
author_rank: Super Contributor
timestamp: May 13, 2024, 10:31:36 pm
content: The circled 2 logo on the package is from Sprague.It could be one of their early Hall effect sensors.
What is this conector type? - Page 1
Forum section: electronics / beginners

author: 001
author_rank: Super Contributor
timestamp: August 22, 2019, 01:14:04 pm
content: HiI`m gonna buy LCD with ribbon wireWhat type connector on PCB I need?

author: mariush
author_rank: Super Contributor
timestamp: August 22, 2019, 01:18:43 pm
content: Flat flex connectors ... figure out number of traces and pitch (spacing between the wires) and thickness of ribbon cable :https://www.digikey.com/products/en/connectors-interconnects/ffc-fpc-flat-flexible-connectors/399The displays don't have the same ribbon cable... the datasheet would normally say or you can determine from drawings.

author: ledtester
author_rank: Super Contributor
timestamp: August 22, 2019, 01:23:08 pm
content: Have a look at:https://www.aliexpress.com/item/32982483720.htmland:https://www.aliexpress.com/item/32858205410.htmlMake sure you get the right pitch.

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: August 26, 2019, 08:58:59 am
content: How about looking into the datasheet for the Display you intend to buy? Most probably they tell you exactly which mating connector should be used.
what is this configuration of opamp ? - Page 1
Forum section: electronics / beginners

author: haseeb zaib
author_rank: Contributor
timestamp: November 22, 2021, 11:34:56 am
content: Hi, I am confused in the configuration of this op-amp. I did this simulation but results are not clear to me, when dc voltage given it is simply acting as a comparator and when AC given I directly get 9V. I don't think this is an integrator because there is no resistor. Can someone explain to me ?

author: oPossum
author_rank: Super Contributor
timestamp: November 22, 2021, 11:48:30 am
content: A resistor is required when the input is a voltage source. Without the resistor the input must be a current source.There will often also be a resistor in parallel with the capacitor to prevent saturation from small DC input offsets. That is know as a leaky integrator.

author: Ian.M
author_rank: Super Contributor
timestamp: November 22, 2021, 12:06:58 pm
content: Assuming a true rail-to-rail OPAMP (i.e. no input common mode range restrictions within its supply rails and an output that can swing to a negligible voltage difference from each rail), the OPAMP has no effect in the circuit!The first parameter of V3 SINE(0 2 100 0), specifies 0V offset and the second specifies peaks of +/-2V. Thus OPAMP In- is always less than the 5.1V bias voltage from V3 on In+, and the OPAMP output is therefore railed at its positive supply voltage (10.6V from V2). Zc ~ 1.6K @100Hz, so the AC current through the capacitor is small compared to a typical OPAMP's output current capability, therefore the circuit is equivalent to simply connecting the capacitor between V3 and V2 with no OPAMP.
What is this connector and where can I buy them? - Page 1
Forum section: electronics / beginners

author: spencer2004
author_rank: Contributor
timestamp: September 25, 2014, 08:09:22 am
content: Hello all.I need a specific connector for a project but I can't find out what it is called or where to buy them. Could someone help me out please?The connector is roughly 5mm wide and the pins are roughly 2mm apart.Sorry for the low quality image.

author: Simon
author_rank: Unknown
timestamp: September 25, 2014, 08:10:24 am
content: I think it is a JST = Japan Solderless Tag

author: Mr.B
author_rank: Unknown
timestamp: September 25, 2014, 08:11:23 am
content: looks like a standard 2mm JST connector to me... Google is your friend.Edit: Simon got in first... LOL...

author: Simon
author_rank: Unknown
timestamp: September 25, 2014, 08:12:31 am
content: Quote from: Mr.B on September 25, 2014, 08:11:23 amGoogle works on the basis that you know what to call it......

author: Dago
author_rank: Frequent Contributor
timestamp: September 25, 2014, 08:14:58 am
content: JST is just a manufacturer not a connector type... I think that is a PH-series connectorhttp://www.jst-mfg.com/product/detail_e.php?series=199

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 25, 2014, 08:16:45 am
content: Quote from: Simon on September 25, 2014, 08:12:31 amGoogle image search is useful for finding connectors - even a vague description wil often get you something close on the first search.Yes, it's a JST PH connector

author: Mr.B
author_rank: Unknown
timestamp: September 25, 2014, 08:19:21 am
content: Sorry Simon, i had intended that now that "we" had identified the likely general classification of JST, that Google would be able to help from there.@mike... Yes, sometimes very useful.

author: nitro2k01
author_rank: Frequent Contributor
timestamp: September 25, 2014, 08:20:12 am
content: In this case though... Yum, now I'm hungry. What was I looking for again?

author: Mr.B
author_rank: Unknown
timestamp: September 25, 2014, 08:23:36 am
content: That's a deliberate ploy by Google to make me turn off my PC and go help the family with dinner...Or prop up some local food manufacturer.

author: spencer2004
author_rank: Contributor
timestamp: September 25, 2014, 08:26:05 am
content: Thanks so much for the very quick replies. I was able to find what I needed now that I know what they are called.
What is this connector called / where could I get more? - Page 1
Forum section: electronics / beginners

author: michaeliv
author_rank: Frequent Contributor
timestamp: September 10, 2015, 07:47:52 am
content: Hi,I have the following connector. Origin unknown. Where would I be able to get more / what should I search for ?Do these type of connectors have a specific name ?It's basically a 4mm cylinder that is part 3mm nut.Thanks!

author: Jesset1996.5
author_rank: Regular Contributor
timestamp: September 10, 2015, 08:54:26 am
content: Could be some sort of rf connector! It looks like Something you would use for a radio antenna connection or even a wifi antenna extention cable. It is attached to coax cable after all so i would look for something similar on the Internet under rf connectors. It could also be a headphone jack of some sort

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: September 10, 2015, 09:12:33 am
content: Looks like an SMB connector although the pictures are not very clear
What is this device in a little 1970's bench power supply? - Page 1
Forum section: electronics / beginners

author: jakeisprobably
author_rank: Regular Contributor
timestamp: June 08, 2019, 07:44:14 pm
content: I took apart a little 12v power supply I picked up from a local thrift store. Inside it's very simple but I've never seen a device before like this little bulb in the pictures. It looks like a bimetallic strip based current limiter. It was in series with the output positive voltage terminal. What are these devices called, and why are they not used (much/if at all) today?

author: ciccio
author_rank: Frequent Contributor
timestamp: June 08, 2019, 07:47:51 pm
content: You are correct: it's a self resetting fuse.Last time I've seen one I was much younger..It is very similar to the bimetallic fuses that are placed inside motor's windings.An example:http://www.miottisrl.com/en/prodotto/sw1/They are current and temperature sensitive (for motor or transformer protection).The glass body make it less temperature sensitive, so it is in effect a simple current limiter.Best regards

author: Towger
author_rank: Super Contributor
timestamp: June 08, 2019, 07:57:47 pm
content: I have also seen them used as a flasher, in ET (phone home) toys!

author: floobydust
author_rank: Super Contributor
timestamp: June 09, 2019, 01:38:42 am
content: It's a self-resetting thermal circuit breaker.They are kind of neat, they trip at say 5A and take almost a minute to reset (cool off).

author: strawberry
author_rank: Super Contributor
timestamp: June 09, 2019, 06:02:16 am
content: old scool cristmass lightscontacts in vacuum can hold more current
What is this diodes function?  - Page 1
Forum section: electronics / beginners

author: BlueSmokedAgain
author_rank: Contributor
timestamp: August 04, 2022, 02:44:04 pm
content: Hi all,Newbie here so sorry if it’s obvious 😜 What is the function of the diode circled in red? I’m guessing it has to do with reverse voltage protection, but I would expect it more in the position of the other diode 1N5401.Many thanks!

author: TimFox
author_rank: Super Contributor
timestamp: August 04, 2022, 02:57:29 pm
content: D5 and D4 protect the rest of the circuit against an accidental reversal of polarity at the DC input plug.The series diode will have a finite leakage current when reverse-biased, and the shunt diode keeps that current from producing a high negative voltage.Belt and suspenders.

author: harerod
author_rank: Frequent Contributor
timestamp: August 04, 2022, 04:10:41 pm
content: Quote from: TimFox on August 04, 2022, 02:57:29 pmJawoll, zis iz how ve do German engineering.Optimal implementation depends, among other things, on the power supply and the device. I like positioning a fuse (melting or PTC) before the normally reverse biased diode to GND. This avoids the diode-drop during normal operation (while adding the fuse's resistance).

author: BlueSmokedAgain
author_rank: Contributor
timestamp: August 04, 2022, 10:22:42 pm
content: Amazing! Thank you! I understand nowI won’t just delete that part from the design then 😂

author: David Hess
author_rank: Super Contributor
timestamp: August 04, 2022, 11:15:18 pm
content: D4 will block the leakage if it is a schottky diode, however U4 is not going to be affected by such a low value of leakage. I suspect someone saw two different protection methods and used them both when that was not necessary.The common pin the 7805 connects to its substrate, which is why it is the middle pin and tab. The junction isolation substrate diode goes to the collector of every transistor, which includes the input. So leakage will forward bias that diode, but it is not going to affect operation.I do not see any reason to include D4.

author: BlueSmokedAgain
author_rank: Contributor
timestamp: August 05, 2022, 09:19:51 am
content: Thank you for the further information. So either I can loose that diode, or if I do keep it, it would be best to change from the current rectifier diode to a schottky equivalent? Is that correct?Thank you for your help with this!

author: David Hess
author_rank: Super Contributor
timestamp: August 05, 2022, 03:10:18 pm
content: Quote from: BlueSmokedAgain on August 05, 2022, 09:19:51 amThat is right; the diode should be a schottky diode to protect an IC from a negative voltage injecting current into the substrate which can cause all kinds of problem, but I do not think that protection is needed here.

author: BlueSmokedAgain
author_rank: Contributor
timestamp: August 05, 2022, 03:29:29 pm
content: Excellent! Thank you!
What is this electronic symbol ? - Page 1
Forum section: electronics / beginners

author: pedroteck
author_rank: Contributor
timestamp: January 12, 2015, 05:18:48 pm
content: Any one familiar with this PCB marking " SG " , i am confused weather its a cap or an oscillator , its connected directly to voltage test probe input of a bench DMM btw.

author: c4757p
author_rank: Super Contributor
timestamp: January 12, 2015, 05:24:14 pm
content: Spark gap, for high voltage overload protection.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 12, 2015, 05:35:18 pm
content: FWIW, the symbol (two plates in a circle) is also sometimes used for normally-open relay contacts on ladder diagrams, or, I suppose, a capacitor that's special in some way (perhaps sealed in a vacuum, hence the circle emphasizing the envelope). There's usually a solid dot inside the circle, denoting a gas filling (gas discharge tubes (GDTs), neon lights, etc.). Alternatives to the straight lines include round, triangle/arrow, or 'D' shaped electrodes, emphasizing the nature or intent of the discharge (from neon glow discharge to high current spark gaps).The "SG" designation and use definitely suggest at least an air type spark gap, in your case.Tim

author: pedroteck
author_rank: Contributor
timestamp: January 12, 2015, 05:55:21 pm
content: Thanks a lot .I see now why its near the voltage input , it acts kind of like a MOV .

author: Dr. Frank
author_rank: Super Contributor
timestamp: January 12, 2015, 09:49:50 pm
content: The symbol origins from a neon discharge bulb, which also ignited on a pre-determined voltage. Can be found in old FLUKE DCV calibrators, or in HP neon bulb choppers.Same effect as a SG, maybe more precise, but for sure more expensive today.Frank

author: pedroteck
author_rank: Contributor
timestamp: January 17, 2015, 02:11:09 am
content: Quote from: Dr. Frank on January 12, 2015, 09:49:50 pmMaybe you have a point Dr.frank since this component belongs to an old bench dmm near the AC/DC voltage input .The problem is that i have lost it and need to replace it with something but not quite sure with what , if it was acting like a MOV i wold replace it with that but i need to be sure .I remember that the component was in a plastic package ( like a small sized polyster cap) with black colour and a encircled T marking on top of it .Like that but a little bigger ( i hope this will help more) :

author: pedroteck
author_rank: Contributor
timestamp: January 18, 2015, 09:24:37 pm
content: Here is a close up view of the inside of the component case :
(resolved) What is this EQ op amp arrangement? Servo amp - Page 1
Forum section: electronics / beginners

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: August 17, 2023, 07:18:16 am
content: What is that arrangement called with the lower op amp?[ Attachment Invalid Or Does Not Exist ]

author: Terry Bites
author_rank: Super Contributor
timestamp: August 17, 2023, 07:54:26 am
content: There is servo action that tends to cancel the DC offsets of the upper amp circuit.If you had a Vos of 4mV and gain of 100 you'd end up with 0.4V DC at the output.Audio opamps tend to have substantial bias currents adding to your offset woes.That's going to create a problem for the next stage.The lower amp is a non inverting integrator.This set up emulates AC coupling without putting big caps in the signal path.You'd usually want a big cap between the inverting terminal resistor and ground, so that cap is eliminated as well.The integrator sets the high pass corner of the LF response too. I cant read the values so it not exactly clear what the response would be.You might want to use a precsion amp for the servo and a high offset voltage but good audio amp for the main signal path.That gives you the best of both worlds, but its probably a bit of a BS circuit from a phile.

author: TimFox
author_rank: Super Contributor
timestamp: August 22, 2023, 03:59:23 pm
content: This circuit is used to combine a high-speed op amp (with mediocre offset drift) with a low-drift op amp (with low speed) toautomaticallyremove the DC offset drift while obtaining high speed.Years ago, a mechanical chopper was used to obtain the low-drift amplifier channel.

author: Terry Bites
author_rank: Super Contributor
timestamp: August 22, 2023, 05:05:53 pm
content: Exactly sir.
What is this for ? - Page 1
Forum section: electronics / beginners

author: Hextejas
author_rank: Frequent Contributor
timestamp: June 25, 2018, 06:39:55 pm
content: This came in a box along with a PCB. My 1st printed circuit board.. It writes a dark brown line.

author: tooki
author_rank: Super Contributor
timestamp: June 25, 2018, 07:29:47 pm
content: It’s a pen. For writing. Looks like it might still have the protective rubber drop on the tip. (Those are on new ballpoint pens to stop them from drying out before use.)

author: bd139
author_rank: Super Contributor
timestamp: June 25, 2018, 09:11:34 pm
content: I got one of those with my last order from them. It is indeed a pen. Take the rubber bit off.Incidentally if you’re a pyromaniac like me, yes it is flammable

author: innkeeper
author_rank: Unknown
timestamp: June 26, 2018, 01:25:08 am
content: same here...looks like it was made with some kind of recycled paper product.unique though.

author: bd139
author_rank: Super Contributor
timestamp: June 26, 2018, 06:50:58 am
content: Oh nice. That stuff spontaneously combusts. Ive been engulfed in a couple of fireballs before and it didn’t put me off. You’re clearly more intelligent than me

author: innkeeper
author_rank: Unknown
timestamp: June 27, 2018, 02:27:35 am
content: it is a manual analog mono printer / plotter. Complete with the storage cover. some were highly prized in the 20th century.
what is this IC - Page 1
Forum section: electronics / beginners

author: Sambh
author_rank: Newbie
timestamp: March 25, 2024, 04:53:09 pm
content: Hi all,Can anyone tell me what does the attached chip do? Is it a timer or a A/D converter? I am unable to find this info by doing a Google search. Any help is appreciated.

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: March 25, 2024, 05:17:16 pm
content: What's the pinout of the chip? Which pins go to ground? VCC? Are any pins tied together?

author: Sambh
author_rank: Newbie
timestamp: March 25, 2024, 05:59:15 pm
content: I do not have these info. All I have are the numbers on the chip. Generally it is pretty straightforward to find the details of an IC from the web with those numbers. But I am having hard luck with this one.

author: ppTRN
author_rank: Regular Contributor
timestamp: March 25, 2024, 06:22:22 pm
content: That's why he was asking for the connections. They will almost immediately tell if it is an op-amp, DCDC converter, power mos ecc...The code on the component is useless in this case unfortunately, we will not find anything on google

author: Vovk_Z
author_rank: Super Contributor
timestamp: March 25, 2024, 06:47:53 pm
content: More info can help us. Like, what a device is? A photo of a whole PCB? Etc, etc.

author: Jwillis
author_rank: Super Contributor
timestamp: March 25, 2024, 06:51:26 pm
content: Zoom out with the picture so people can see the traces and other components that may be connected to it. Even if the power pins can be determined it can narrow down plausible identifications.

author: the Chris
author_rank: Regular Contributor
timestamp: March 25, 2024, 07:20:00 pm
content: Is a hall effect current sensor a plausible identification? 1100 + that TI logo + what could be am SOIC8 package =https://www.ti.com/lit/ds/symlink/tmcs1100.pdf

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 07:26:06 pm
content: Quote from: Sambh on March 25, 2024, 05:59:15 pmThen get said information.It's normally pretty easy to figure out which pins are for the power supply. Look at the traces. The power supply normally has a fairly decent sized capacitor across it. The 0V usually goes to many other components on the board. If you know the part numbers for other ICs, you can figure out which pins are their power supply and use a multimeter to test for continuity between them and your unknown IC.

author: Sambh
author_rank: Newbie
timestamp: March 26, 2024, 07:52:41 pm
content: Thanks to everyone for your reply. Here is a new image. I think it is a current monitor.

author: DavidAlfa
author_rank: Super Contributor
timestamp: March 26, 2024, 08:14:03 pm
content: Q1 label + all the joined legs in the footprint highly suggests this is aTPS1100mosfet, the datasheet marking matches "1100".Ti has a marking search page:https://www.ti.com/packaging/en/docs/partlookup.tsp

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: March 27, 2024, 06:49:58 pm
content: Quote from: DavidAlfa on March 26, 2024, 08:14:03 pmThis will be my vote as well, as the "gate" pin is also in the same location.
What is this IC / component? - Page 1
Forum section: electronics / beginners

author: brandon.arnold
author_rank: Contributor
timestamp: November 16, 2024, 10:53:32 pm
content: May I ask if anyone can take a look at the image and help me understand what this component does?I have circled 4 of them, there, labeled "103" on the IC, with mask label prefix "RB...". There are 9 contacts, which are 8 pins + a large contact that has continuity with +5V (VCC). Each of the 8 pins are connected to different TTL digital bus data wire.Maybe they are pull-up resistors. Or something to do with static / safety protection, using 8 capacitors, for example.Thank you!

author: u666sa
author_rank: Frequent Contributor
timestamp: November 16, 2024, 11:00:09 pm
content: Resistor network. Yes, pull up resistors, only inside one package, instead of individual resistors.

author: brandon.arnold
author_rank: Contributor
timestamp: November 16, 2024, 11:03:33 pm
content: Thank you so much, u666sa.
What is this measurement in a datasheet? - Page 1
Forum section: electronics / beginners

author: rea5245
author_rank: Frequent Contributor
timestamp: July 13, 2021, 06:46:21 pm
content: Hi,I've come across a notation in a datasheet I don't understand.What do "2-0.9" and "3-1" mean in this diagram (units are mm)?Thank you,Bob

author: Benta
author_rank: Super Contributor
timestamp: July 13, 2021, 07:20:55 pm
content: From what I see, they don't mean anything. I suspect a PDF creation error from the manufacturer."2-" might be a substitute for ø (diameter). "3-" no idea.

author: elekorsi
author_rank: Regular Contributor
timestamp: July 13, 2021, 07:37:37 pm
content: I agree, it must be an error in the pdf... I would say that the pin is 0.9 x 0.4 and the specified hole is dia. 1mm with +0.1 tolerance

author: HwAoRrDk
author_rank: Super Contributor
timestamp: July 13, 2021, 07:50:56 pm
content: If they both said "2-", then I would say they mean that there are two holes/pins of the given dimension. Maybe the "3-" is a typo.

author: drvtech
author_rank: Regular Contributor
timestamp: July 13, 2021, 10:27:28 pm
content: I suspect that the reply above is correct and that the 3 is the result of someone copying and pasting from the drawing for the spdt switch, which would indeed have 3 holes

author: timenutgoblin
author_rank: Regular Contributor
timestamp: July 14, 2021, 01:08:32 am
content: Quote from: rea5245 on July 13, 2021, 06:46:21 pmThe "2-0.9" refers to the fact that there are 2 pins that are 10.16mm apart measured between their centres.The "3-1" refers to the fact that there are 3 - not 2 - collinear PCB mounting holes that are 5.08mm apart measured between their centres. The drawing only shows 2 of the 3 collinear holes that are required. The distance measured between the 2 outer PCB mounting holes would measure 10.16mm to accommodate the 2 pins of the switch.There is no typo or error - it is intentional.

author: elekorsi
author_rank: Regular Contributor
timestamp: July 14, 2021, 05:46:24 am
content: I have never seen it written like that, for me it's an error. And beleive me, i have seen some mechanical drawings...If you want to specify multiple dimension, you write 2x or 3x, for our example it means 2x 0.9 and 3x 1 and not some confusing minuses
What is this part? (photo included) - Page 1
Forum section: electronics / beginners

author: Dan Moos
author_rank: Frequent Contributor
timestamp: July 04, 2023, 10:37:38 pm
content: Reads like 4 pF. I'm not convinced its a cap though. No other markings other than what are shown.

author: Benta
author_rank: Super Contributor
timestamp: July 05, 2023, 12:53:03 am
content: Ceramic cap in the pF range. Looks like an old Philips type.1 pF could be right, but unusual.

author: ArdWar
author_rank: Frequent Contributor
timestamp: July 05, 2023, 03:35:26 am
content: I was wondering when the last time anyone see color-coded capacitor until I realize the color don't exactly make sense.Maybe the base is supposed to be white/gold, which means it should be 2.7pF

author: srb1954
author_rank: Super Contributor
timestamp: July 05, 2023, 06:17:54 am
content: Quote from: Dan Moos on July 04, 2023, 10:37:38 pmPhilips 2222 680 series ceramic cap 1pF, probably 100V rated.This series of capacitors is intended for temperature compensation applications and the red/violet coding is for the temperature coefficient; in this case +100ppm/℃ (P100)Other temperature coefficient colour codes:Black NP0Red -75ppm/℃ (N75)Orange -150ppm/℃ (N150)Yellow -220ppm/℃ (N220)Green -330ppm/℃ (N330)Blue -470ppm/℃ (N470)Violet -750ppm/℃ (N750)The extra 3pF you are measuring is probably stray capacitance. You need to zero out your meter or test fixture before measuring such small capacitors.
What is this part called? (Requesting search terms) - Page 1
Forum section: electronics / beginners

author: TannerFrisby
author_rank: Newbie
timestamp: September 28, 2020, 11:50:30 pm
content: Quick description of the project:I am trying to create a low current device (battery-powered) that listens for an RF signal and then performs a task. Both current consumption and cost are major factors.Present implementation:For the prototype, I am using an esp-32 (nominal 10ua deep sleep, enough io pins, Arduino IDE) and a HopeRF RFM83C (measured 5ma on, assumed nominal 3ua shutdown, acceptable RF sensitivity). Currently, the RF receiver is always on and the first 433mHz signal it hears will interrupt the esp-32 from deep sleep. While it should be possible for the esp-32 to interpret the remainder of the received signal and parse the instruction at the end, it is above my current programming level and I'll save it for future development. Instead, the esp-32 waits for the second sending, which requires the user to continue holding down the RF remote's button (less than ideal, but not really an inconvenience). As the first transmission from the RF receiver to the ESP-32 is lost (due to wake-up), I would like to lower the RF receiver's duty cycle to the point where it will wake up within the transmission window of one message (~35ms I think) "listen" for a few cycles of ~285us 1's and 0's and then be latched "on" by the ESP-32 for the next message if and only if it "heard" something causing an interrupt to wake up the ESP-32.My request:I don't know what an IC like this would be called? Wake-up timer IC? PWM timer IC? I would like the device to oscillate with a square wave of some duty cycle between high (active shutdown of RF receiver) and low (allowing the receiver to listen for a few cycles). Duty cycle and period adjustability would be ideal to help with tuning. Sub-milliamp current would be great. If it takes more than 3ma or so, then it's not even worth it.Search results:I found "wake-up" ICs, but they appear to be just a pulse (i.e. adjustable period, but near zero percent duty cycle). I looked at a 555 timer but the example I saw had 10ma draw and a handful of suport passives. Ideally the IC I'm looking for wouldn't require any support peripherals and would have very low current draw.Thank you to all who have taken the time to read this and help me out,Tanner Frisby

author: ledtester
author_rank: Super Contributor
timestamp: September 29, 2020, 03:00:14 pm
content: I think what you are describing is a multivibrator which can be "gated".Have a look at this page:https://www.allaboutcircuits.com/technical-articles/how-to-design-schmitt-trigger-oscillators/and, in particular, where you see this graphic:This article on Schmitt triggers might also be helpful:https://www.allaboutcircuits.com/technical-articles/exactly-how-schmitt-trigger-oscillators-work/The CD4093 is an extremely low power chip - itself only consuming in the single microamps. The power consumption of the RC timer will largely depend on the capacitor you use -- smaller will use less current.
what is this part called - Page 1
Forum section: electronics / beginners

author: CoopedUp
author_rank: Regular Contributor
timestamp: June 15, 2019, 12:16:12 am
content: I have this "rotary" selector switch thing. From what I gather is you get some sort of binary output for whatever number it's on I just don't know what it's called or who made it. Thanks

author: thm_w
author_rank: Super Contributor
timestamp: June 15, 2019, 12:26:28 am
content: Pushwheel or thumbwheel switch.They make them with decimal or binary coded outputs on the back, depending on what you want to hook up.https://www.aliexpress.com/item/2026646090.html(this is pushwheel style, with buttons)https://www.digikey.ca/product-detail/en/c-k/332100000/CKN11145-ND/3855234(thumbwheel style like yours)https://www.digikey.ca/product-detail/en/c-k/302119N00/CKN1866-ND/1012172

author: Andy Watson
author_rank: Super Contributor
timestamp: June 15, 2019, 12:43:30 am
content: Another vote for "thumb-wheel"

author: CoopedUp
author_rank: Regular Contributor
timestamp: June 15, 2019, 12:48:04 am
content: Thanks, I knew what it did just no clue what it's name was.
What is this part called? - Page 1
Forum section: electronics / beginners

author: DudeGibbs
author_rank: Contributor
timestamp: March 20, 2017, 07:23:16 pm
content: Please see attached image. What is the name of this part? Its flexable metal with rubber that has a washer at one end. Used for cable management. I would like to order more of these but dont know what they're called or how to find them.

author: JRosario
author_rank: Contributor
timestamp: March 20, 2017, 08:15:09 pm
content: I have this problem a lot.There is no resource that I know about for the names of some of these smaller parts.Along with an answer, if anyone could provide me a resource for this type of information, that would be greatly appreciated.

author: alm
author_rank: Super Contributor
timestamp: March 20, 2017, 08:27:50 pm
content: I find paper catalogs sometimes useful for this. You can quickly flick through the relevant section and look for a matching picture.

author: tecman
author_rank: Frequent Contributor
timestamp: March 20, 2017, 08:30:27 pm
content: I am not sure it has a proper name. If you need some, just get some solder lugs and solid copper wire Solder the wire to the lug and cober with some insulating sleeving or heat shrink.Paul

author: bitwelder
author_rank: Super Contributor
timestamp: March 20, 2017, 08:34:40 pm
content: Quote from: DudeGibbs on March 20, 2017, 07:23:16 pm"Cable clip bendable fastener" perhaps?http://www.digikey.com/product-detail/en/essentra-components/VCC-83540/RPC1454-ND/395796I was just opening Digikey page and browsing through all their category "Cable support and fasteners"BTW, I stopped searching at the 2nd page. There might be something else in the other 11 after.

author: Mickster
author_rank: Contributor
timestamp: March 20, 2017, 09:04:07 pm
content: Cushioned cable routing clip?http://www.efc-intl.com/products/half-loop-screw-mount-flexible-clips-wvinyl-coating.htm

author: grifftech
author_rank: Frequent Contributor
timestamp: March 21, 2017, 08:58:09 pm
content: Quote from: tecman on March 20, 2017, 08:30:27 pmTypo found

author: Mickster
author_rank: Contributor
timestamp: March 21, 2017, 09:46:19 pm
content: Quote from: grifftech on March 21, 2017, 08:58:09 pmB is beside v on the keyboard, not that difficult to interpret what was intended.P.S. Period missing.

author: james_s
author_rank: Super Contributor
timestamp: March 21, 2017, 09:59:53 pm
content: I have that problem a lot with connectors, and yes, a paper catalog can be very helpful for that.

author: lowimpedance
author_rank: Super Contributor
timestamp: March 21, 2017, 11:18:06 pm
content: Quote from: alm on March 20, 2017, 08:27:50 pmThis is the very reason I keep the old paper catalogues.Since each supplier likes to call categories of parts by different names making it damn impossible to use the same search terms between them. For example I recently went looking for "class X suppression capacitor" on RS.And this pain in the butt exercise pervades many areas of the on line searching.So I will NOT be recycling my 'well worn' paper cat's any time soon.
What is this part on a CRT board?  - Page 1
Forum section: electronics / beginners

author: RyanG
author_rank: Regular Contributor
timestamp: October 15, 2017, 01:29:26 am
content: https://imgur.com/gallery/o0WuHWhat is that part? I was guessing some sort of spark gap because it's connected across the mains input.

author: RyanG
author_rank: Regular Contributor
timestamp: October 15, 2017, 01:37:01 am
content: Found the answer. It had a patent number on the back side.http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=4438365.PN.&OS=PN/4438365&RS=PN/4438365
What is this part? Sprague Low/High pass filter? - Page 1
Forum section: electronics / beginners

author: denimdragon
author_rank: Regular Contributor
timestamp: May 22, 2022, 11:05:43 pm
content: So I have a few of these Sprague mystery components. I am assuming it is a filter in one package. The "Paktron" partnext to it has the resistor and capacitor symbols shown and it seems to be a filter as well. Am I correct?

author: TimFox
author_rank: Super Contributor
timestamp: May 22, 2022, 11:07:31 pm
content: They are series resistor-capacitor combinations, but not filters.The values are printed clearly on both parts.Could be used as snubbers or other shunt protection circuits.
What is this part? - Page 1
Forum section: electronics / beginners

author: paul_allsopp
author_rank: Newbie
timestamp: March 03, 2017, 09:44:14 pm
content: Can someone tell me what this SMD component is (R56)? I assume it is a fuse, but not sure.https://drive.google.com/file/d/0B1uriJhzSGi-bzRqQ284SFQ4ajlPS3NoNi04NS1mbnhiWVdR/view?usp=sharingIt's part of this circuit I am trying to figure out (part is bottom left):https://drive.google.com/file/d/0B1uriJhzSGi-WUF2MXNoMXhFOE9Zb05EZ0QwaWsxUHdGQ0dr/view?usp=sharingThis is the board:https://drive.google.com/file/d/0B1uriJhzSGi-Yk9jQnNzZWk5WEk/view?usp=sharingI have a 3D printer (DaVinci 2 Duo) and suddenly both extruders stopped heating. I remove them, put them on my bench PSU at 12v and 2.4A and they both heat up just fine. So I put a meter on the thermistor to make sure that was not faulty, but they both work. So I started looking at the board, and noticed that if I put a meter from ground on the PSU for the printer and the power pin on one of the extruder sockets, one socket reads zero. So I shorted one of those components to bypass it and the extruder is getting the required 12v@2.4A. This leads me to believe this component is a fuse that has blown.Replacing it is just the tip of the iceberg though, as with the bypass in place, turning on the printer, the extruder starts to heat without any instruction to. Then the other extruder also has an issue whereby the component is not compromised, but I still get no power to the extruder...this could be a bad heating element in the extruder though, so I will replace that and test it again.I'm loath to just replace the board because they cost $200USD, and I may be able to fix it for a few bucks.ANY help at all is very appreciated. Talking to the DaVinci community, it seems that just about everyone is having similar issues, with some members on their 5th board within the 1-year warranty. Unfortunately I am outside my warranty.Thanks all.Paul

author: Benta
author_rank: Super Contributor
timestamp: March 03, 2017, 10:03:35 pm
content: Your "Google Drive" links don't work.

author: bktemp
author_rank: Super Contributor
timestamp: March 03, 2017, 10:04:00 pm
content: Looks like a fuse.According to this it could be 5A, but is hard to guess without knowing the manufacturer and its marking code system.http://www.farnell.com/datasheets/1716418.pdf

author: sleemanj
author_rank: Super Contributor
timestamp: March 03, 2017, 10:06:55 pm
content: I expect you have already read these, but just in case...https://www.3dprintingforum.org/forum/hardware/manufacturers/xyzprinting/3384-extruders-not-heating-on-da-vinci-2-0-duohttps://forum.voltivo.com/showthread.php?tid=8517

author: coyote20000
author_rank: Newbie
timestamp: March 05, 2017, 06:26:17 pm
content: Designation is 'R'. Most likely a resistor. Odd that it has no numbers. Could be a 0 ohm.bktemp might have it right, but why would the label be R?Take it off and measure it..
what is this piercing insulation connector called? - Page 1
Forum section: electronics / beginners

author: ledtester
author_rank: Super Contributor
timestamp: May 16, 2018, 07:22:59 pm
content: I'm wondering what these connectors are called (see attachments).They seem similar to the Molex KK series connectors, but instead of crimping the ends of the wires you can just push them down into the housing and the wire's insulation is pierced to make contact.Are the housings still available? Do you need a special tool to insert the wires?

author: fourtytwo42
author_rank: Super Contributor
timestamp: May 16, 2018, 07:24:35 pm
content: IDC (Insulation Displacement Connector) and yes they love to sell you special tools but a flat bladed screwdriver of an apropriate size usually works for those (dont strip the wire).

author: wraper
author_rank: Unknown
timestamp: May 16, 2018, 07:53:16 pm
content: I don't advise using this type of connector if you care about reliability. Seen too many with wire loosing connection or even falling out. Special tool is needed. You can sort of use a flat screwdriver to push the wire in but reliability will be atrocious.http://www.te.com/global-en/products/connectors/pcb-connectors/intersection/mta-100-mta-156-connectors.html?tab=pgp-story
What is this power meter reading in dB and Watts please? - Page 1
Forum section: electronics / beginners

author: Chris Wilson
author_rank: Super Contributor
timestamp: April 06, 2023, 11:37:55 am
content: I am both a newcomer to power measurement and have a Marconi power meter which is also new to me. I am measuring at 2.4 GHz to a POTY antenna on a satellite dish.The directional coupler is -20dB and in the feed from the coupler to the Marconi meter power head is a -30dB attenuator.I am struggling to work out in both dB and Watts how much power is shown going to the antenna, would anyone be kind enough to help me out please? Thanks, the photo of the meter reading is athttp://www.chriswilson.tv/power-reading.jpg--

author: wasedadoc
author_rank: Super Contributor
timestamp: April 06, 2023, 11:49:41 am
content: The meter is reading 132 microwatts. You have 50 dB attenuation. 100,000. So 13.2 Watts to the dish.Why 2.4GHz? It is absorbed by water - rain, mist fog, clouds. That is why microwave ovens run at 2.4GHz

author: Chris Wilson
author_rank: Super Contributor
timestamp: April 06, 2023, 12:18:36 pm
content: Thanks for showing me the way to read it, I see now the 1 to 3 and 1 to 10 scales are uW and the bottom one is dB... Duh!The Oscar 100 satellite carries a transponder for amateur communications, both narrow band SSB and CW and wide band digital amateur TV. It receives around 2,4 GHz and transmits around 10GHz. I use it for both. My main amp is a max 20W so given the drive I used your calculations are good to see and what I hoped for. I can easily overload the transponder even with 20W and a big dish.Thanks again, appreciated.

author: mikerj
author_rank: Super Contributor
timestamp: April 06, 2023, 09:47:36 pm
content: Quote from: wasedadoc on April 06, 2023, 11:49:41 amThis is often quoted but isn't true. Water has a very broad absorption spectrum at microwave frequencies and 2.4GHz is nowhere near the peak (which is very temperature sensitive, ~180 GHz at 0C down to around 10 GHz at 100C). The apparently sub-optimal frequency of 2.4GHz is used because it penetrates further into the item being cooked, helping it to heat more evenly. If operated around the absorption peak only the surface would get heated.
What Is This Press On The End Of Lead? - Page 1
Forum section: electronics / beginners

author: Boris_yo
author_rank: Frequent Contributor
timestamp: November 24, 2011, 10:36:53 am
content: I have seen this tiny thing when i was a kid several times but in recent years i don't remember seeing anything like this and i did not use this:If i understand correctly, this little (aluminium?) part is for pressing leads that have a lot of tiny wires in them so the will not escape and remain tied together?

author: LEECH666
author_rank: Frequent Contributor
timestamp: November 24, 2011, 11:55:41 am
content: I think those metal fittings are called ferrule or wire end sleeves in English.I also came across the word core cable ends, but that seems to be less common of a term.It's a very essential means to make braid wires (flexible wires) connect to a screw terminal type connector.Cheers,Florian

author: LEECH666
author_rank: Frequent Contributor
timestamp: November 24, 2011, 11:57:28 am
content: From Wikipedia:A Ferrule is:Quote

author: mobbarley
author_rank: Regular Contributor
timestamp: November 26, 2011, 09:13:06 am
content: Also called bootlace ferrule or bootlace crimp

author: Boris_yo
author_rank: Frequent Contributor
timestamp: November 26, 2011, 12:25:47 pm
content: Thanks guys. All the picture i posted on this forum, i took with 5MP smartphone. Can't imagine myself without it when it comes to stuff like that. And ferrule picture i shot with attached $2 plastic lens which came out not bad considering the price of lens and quality.
what is this resistor? - Page 1
Forum section: electronics / beginners

author: electricenthusiast
author_rank: Contributor
timestamp: December 18, 2022, 11:11:11 am
content: what is this kind of resistor? i couldn't find it anywhere. Im sure its not a variable resistor

author: CountChocula
author_rank: Unknown
timestamp: December 18, 2022, 12:24:25 pm
content: The image is really low res, so it’s somewhat hard to tell, but that looks like a varistor. Cheers!

author: jonpaul
author_rank: Super Contributor
timestamp: December 18, 2022, 12:28:02 pm
content: Symbol for varistor or thermal sensor.Please Send a phot of the device and much better res of schematic, your image is very low resj

author: electricenthusiast
author_rank: Contributor
timestamp: December 19, 2022, 07:50:34 am
content: here it is (see image)

author: tooki
author_rank: Super Contributor
timestamp: December 19, 2022, 08:05:25 am
content: From the part number — which you easily could have googled yourself — it’s a Polyfuse, a self-resetting fuse. (They work through thermal expansion: they’re made from polymer filled with metal particles. As it heats up from overcurrent, the polymer expands, separating the metal particles enough that continuity is broken. As it cools off, it shrinks and continuity is reestablished.)

author: Terry Bites
author_rank: Super Contributor
timestamp: December 21, 2022, 05:50:09 pm
content: Swelling?

author: Vovk_Z
author_rank: Super Contributor
timestamp: December 24, 2022, 07:37:29 am
content: Zigzag sine means 'variable'. It has to have letter 'T' to express termal-dependent device 'Thermistor'.If there were a 'V' letter then it is voltage-dependent device - varistor.Etc.

author: tooki
author_rank: Super Contributor
timestamp: December 24, 2022, 10:31:07 am
content: Zigzag is simply the ANSI (American) symbol for a resistor — any resistor. It’s the overlaid symbol that makes it a varistor, and T to indicate that it’s temperature dependent.
What is this RF connector? - Page 1
Forum section: electronics / beginners

author: sonnytiger
author_rank: Frequent Contributor
timestamp: September 13, 2015, 03:14:48 am
content: I think it's an N type? I have compared it with images of many connectors but I can't be sure.Thanks!

author: xrunner
author_rank: Super Contributor
timestamp: September 13, 2015, 03:17:25 am
content: TNC maybe.

author: sonnytiger
author_rank: Frequent Contributor
timestamp: September 13, 2015, 03:21:26 am
content: Yes! I think it is a TNC, I just looked another picture that popped up on google, looks identical to the one in the picture.Thanks!

author: AF6LJ
author_rank: Unknown
timestamp: September 13, 2015, 03:27:36 am
content: Looks like a TNC normal polarity.Yes they do make them with a male pin in the center of the connector.We use to use them all the time at Loral Corp. My paperweight has a TNC connector on it.

author: sonnytiger
author_rank: Frequent Contributor
timestamp: September 13, 2015, 05:45:29 am
content: That's awesome, thank youThe connector in question is on a audiovox car phone.I wish I could find a use for it...

author: AF6LJ
author_rank: Unknown
timestamp: September 13, 2015, 12:51:54 pm
content: Quote from: sonnytiger on September 13, 2015, 05:45:29 amThen it is a TNC.Like an N and BNC connector it is a constant impedance. connector.The picture above shows one being used on a 2.2GHZ FM telemetry transmitter.