hybridfree/eevblog-posts huggingface dataset:
Jumper for 2 independent diodes for SOT-227 - Page 1
Forum section: electronics / beginners

author: mike buba
author_rank: Contributor
timestamp: February 18, 2022, 10:20:12 am
content: Hi, is there a jumper anywhere to buy to connect 2 anodes and 2 cathodes?[ Specified attachment is not available ]I am looking for a single diode, but all SOT-227 configurations are 2 independent. it looks too tight to use a crimp ring terminal and do a wire connection

author: Siwastaja
author_rank: Super Contributor
timestamp: February 18, 2022, 11:57:00 am
content: If you do power electronics, I recommend you get some copper sheet in different thicknesses (0.3mm is good all-around thickness, still cuttable with normal scissors).So you can just cut your own in matter of minutes.Do remember that paralleling diodes is not necessarily straightforward. In such package though they are fairly well thermally coupled so it works out, but still some derating is usually needed.Using two wires with their own lugs, and combining these wires later at their destination is probably the simplest option.

author: langwadt
author_rank: Super Contributor
timestamp: February 18, 2022, 12:17:52 pm
content: Quote from: Siwastaja on February 18, 2022, 11:57:00 amand the wire resistance will help a bit with current sharing

author: Siwastaja
author_rank: Super Contributor
timestamp: February 18, 2022, 03:09:57 pm
content: Quote from: langwadt on February 18, 2022, 12:17:52 pmYes, with the positive tempco of copper helping even more, but you really need to calculate the resistance instead of just relying on "a bit". The effect might be orders of magnitude less than you expect.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 18, 2022, 03:16:05 pm
content: To what end -- is this at high frequency, mains, DC? How is it wired, that there is room for a jumper?Does the datasheet say the dies are matched, so they are okay to wire in parallel? (Dual diodes are often separate dies, so their temperatures won't track as well as could be. As a result, the maximum current rating for two in parallel, will be somewhat less than double the rating of each diode. How much depends on how well matched they are.)Tim

author: mike buba
author_rank: Contributor
timestamp: February 18, 2022, 07:05:53 pm
content: It is for the output diode in a boost converter configuration, fsw > 20 kHz. It will sit on the same heatsink as MOSFET (most like also SOT-227 housing).For the diode,it says: Positive temperature coefficient for safe operation and ease of paralleling.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 18, 2022, 07:34:24 pm
content: Oh, SiC, yeah internal resistance dominates and has a PTC. No problem!Tim
Jumper wire organization ideas...? - Page 1
Forum section: electronics / beginners

author: drcheap
author_rank: Newbie
timestamp: August 17, 2015, 05:27:18 am
content: You know those 100s (1000s?) of little jumper wires you have that are super handy when working up a prototype on a breadboard...?(A small sampling of mine that recently got scattered about by a small furry creature)I have mostly male/male for breadboarding, but also some male/female & female/female that are handy for connecting to/between header pins of various boards. There are also various lengths, and less importantly (for storage purposes) different colors. I have yet to find a good way to store these things so that they are easily/quickly accessible, ideally with separation between gender pairs as well as lengths.I'm interested in seeing what sort of system some of you guys have come up with to store them. I know some people just throw them in a box/bin and create colorful spaghetti, but I'm trying to find something with a lower random seek time. The last thing I want to do in the middle of wiring up a circuit is spend 3 minutes hunting down a suitable jumper wire for the connection-of-the-moment.

author: ataradov
author_rank: Super Contributor
timestamp: August 17, 2015, 05:53:17 am
content: Those plastic storage bins (24 compartments typically) are very handy. They usually have long horizontal compartments molded into the box itself and vertical compartments are created by removable plastic dividers.Possible compartment sizes are very well matched to the length of the typical jumper wires.

author: drcheap
author_rank: Newbie
timestamp: August 17, 2015, 06:19:34 am
content: Yeah, I tried that, it was not exactly an efficient use of the container (and thus many containers would be needed). Maybe I need to find better size/shaped containers

author: ataradov
author_rank: Super Contributor
timestamp: August 17, 2015, 06:29:44 am
content: Yeah, you need to find a bigger box. Here is one of mine. As you can see, those 2x1 compartments fit the shorter wires perfectly.
Junk! - Page 1
Forum section: electronics / beginners

author: nick.sek
author_rank: Regular Contributor
timestamp: May 21, 2012, 02:40:23 am
content: Hey everybody, last week my friend was cleaning out his garage and we found an old tube amp! Which I was so excited about, it comes from a time without any PCBs. I had it up and running in a couple of hours, after I cleaned it and got a setup going for my guitar. And the point of this is asking where do you find things to tinker with.I got some cool outlets, we have a recycling bin at my school were people can throw stuff out that relate to electronics but I was wondering if you guys have any tips for finding interesting "junk".Nick

author: Psi
author_rank: Super Contributor
timestamp: May 21, 2012, 03:05:39 am
content: Some countries have an yearly in-organic rubbish collection where people put objects (to large for the regular rubbish collection) outside the house on the grass verge for special collection.Things like TVs, Fridges, Radios, and lots of other stuff.It's always a free for all when it happens here.You never leave you lawnmower outside to go get more petrol when it's happening

author: vk6zgo
author_rank: Super Contributor
timestamp: May 21, 2012, 04:49:26 am
content: Look around for "Hamfests".Things aren't free,but if you are looking for odd bits you will be able to pick them up cheaply.At one time,various companies which use Electronics would give away obsolete stuff to Electronics enthusiasts,as it cost more to dump them or sell them.The "Health & Safety" freaks have pretty much put paid to that,though!Sometimes you can find stuff at ordinary swapmeets,but,again,not as much as in earlier times,as people are wary of being sued if some halfwit buys Electrical equipment & blows himself up!

author: amyk
author_rank: Super Contributor
timestamp: May 21, 2012, 07:35:54 am
content: If you're into digital logic and computers, you can often get tons of them for free (or almost) from the recycling centers. Old motherboards are a good source of MOSFETs and also make for nice SMD practice boards. You can get power transistors and rectifiers from discarded PSUs.
Just a quick one: Grounding the DAC chip (LTC1450) - Page 1
Forum section: electronics / beginners

author: Chris_PL
author_rank: Contributor
timestamp: April 03, 2014, 06:55:57 pm
content: Hi all, just a quick one. All of the integrated DAC'a I've been working with had separate AGND and DGND connections - no problem whatsoever. Then there is this LTC1450 from Linear I have to use and it appears it has only one GND pin.I have separate analog and digital ground planes connected only in one point, in the power supply section, and the question is : Should I connect this DAC to analog or digital ground? The datasheet doesn't say a thing about it, and I just don't want to end up with a huuuuge ground loop + second AGND-DGND connection point...

author: gxti
author_rank: Frequent Contributor
timestamp: April 03, 2014, 11:05:01 pm
content: In that case (and probably other cases) the planes should connect at the ADC instead of at the power supply.
Just an idea ?????? - Page 1
Forum section: electronics / beginners

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: January 09, 2013, 05:42:41 pm
content: I was soldering and had a thought and wanted to see what you guys think of it ... What would happen if I took the elements out of my soldering iron and coated it with thermal compound and put it all back together and tried using it like that???

author: Monkeh
author_rank: Super Contributor
timestamp: January 09, 2013, 05:55:38 pm
content: You'd make a disgusting stinky mess, because it's not meant to operate at those temperatures.

author: IanB
author_rank: Super Contributor
timestamp: January 09, 2013, 05:56:41 pm
content: The thermal compound will bake, decompose, make a horrible mess and ruin your soldering iron. Don't even think about it.

author: SeanB
author_rank: Super Contributor
timestamp: January 09, 2013, 07:52:15 pm
content: Use Copaslip instead, it will work at high temperatures.

author: robrenz
author_rank: Super Contributor
timestamp: January 09, 2013, 08:02:14 pm
content: If the heater shell ismetal and electrically isolatedand you really want good thermal transfer and you can remove the tip while still hot. Separately tin the heater and tip where they contact and put a short length solder between them. assemble with the heater on and let the solder melt forming a liquid metal heat transfer medium. That will definitely improve the thermal transfer to the tip.But I don't suggest actually doing this

author: jeroen74
author_rank: Frequent Contributor
timestamp: January 09, 2013, 08:20:18 pm
content: Copaslip will probably ruin your clothes if you accidentally get it on them.

author: PA0PBZ
author_rank: Super Contributor
timestamp: January 09, 2013, 08:24:19 pm
content: Quote from: robrenz on January 09, 2013, 08:02:14 pmIt will probably drip out at the most unconvenient moment and burn your sock

author: vortexnl
author_rank: Contributor
timestamp: January 09, 2013, 11:21:12 pm
content: I think tinkering with something that is not a circuit board is always a bad idea!
Just another Cap Question - Page 1
Forum section: electronics / beginners

author: tdoubht
author_rank: Newbie
timestamp: July 14, 2015, 02:47:59 pm
content: Hello, first post.I searched but couldn't find the specific answer for my questions.I watched the Dave's capacitor post and remind me of an old project I was trying to build, but I couldn't find the correct answer in that time, so I is frozen.1)The main idea is to build a High-voltage discharge pulse current for Neodymium magnet magnetizer.I am able to size everything, except the right capacitor (not value, but the type - maybe film?) able to withstand high pulse discharge. Which one I should use and why?2)I need to build a signal conditioner for a piezo accelerometer. Normally, they use a bias capacitor for DC filtering. Where can I found more information about sizing that capacitor with the correct type?

author: tdoubht
author_rank: Newbie
timestamp: July 16, 2015, 03:35:52 am
content: No one?

author: Mr.B
author_rank: Unknown
timestamp: July 16, 2015, 03:41:35 am
content: Welcome to the forum.In order to tap the incredible knowledge resource of this forum and to benefit from the help of other people you need to ask the questions and provide as much supporting data as you can.Schematics are a good start...Datasheet reference for your accelerometer...etc.

author: tdoubht
author_rank: Newbie
timestamp: July 16, 2015, 04:19:29 pm
content: Thanks Mr.B,Regarding the datasheet, both applications are almost standard. But I have attached my accelerometer datasheet.Mainly, it should have 12Vdc Bias Voltage with a 24Vdc power. The other infos is what I am trying to get. Just put a circuit "dummy load" like will work?! I really don't know. It relies on the sensor it self. I have no idea and I was hopping someone did something nearly like and if can give me some infos.Any way, the standard circuit is shown above:About the capacitor and high-voltage, there are no datasheets, I just need high capacitor values able to withstand high and real fast current draw. There are plenty of circuits able to generate high-voltage, but I suspect they are related to which capacitor I will use.Exemple:

author: tdoubht
author_rank: Newbie
timestamp: July 19, 2015, 03:05:16 am
content: Any suggestion?

author: leblanc
author_rank: Regular Contributor
timestamp: July 19, 2015, 12:41:10 pm
content: Take a look at motor start capacitors.If you are looking to demagnitize, how are you going to ensure that you don't remagnitize in the opposite direction?

author: tdoubht
author_rank: Newbie
timestamp: July 19, 2015, 10:50:11 pm
content: Film capacitorsJust what I expected.The magnetization direction is not a problem since my magnet is round shaped.I have a lot of electrolytic capacitors. Do you think I can give it a try?

author: leblanc
author_rank: Regular Contributor
timestamp: July 20, 2015, 11:41:39 pm
content: I would certainly enclose the caps in a solid box, in case they blow up, which can do some serious damage.
just burnt my first potentiometer 😢. - Page 1
Forum section: electronics / beginners

author: renzoms
author_rank: Regular Contributor
timestamp: December 09, 2021, 08:28:56 pm
content: wanted to share. didnt find a channel for it.

author: emece67
author_rank: Frequent Contributor
timestamp: December 09, 2021, 09:03:57 pm
content: .

author: WattsThat
author_rank: Frequent Contributor
timestamp: December 10, 2021, 04:26:22 am
content: Generating smoke is easy. Just wait until things start to explode. The life long journey of learning is just full of surprises.

author: xavier60
author_rank: Super Contributor
timestamp: December 10, 2021, 04:38:17 am
content: For Potentiometers that I use for experimenting, I insert a 1KΩ resistor in series with the wiper's fly lead.

author: Capernicus
author_rank: Frequent Contributor
timestamp: December 10, 2021, 05:34:16 am
content: I bet carbon printed pots take more amps than wire wound ones, with wire wound pots the wire is only a hair thickness, cant take much power at all. and it always frizzles at the beginning, makes u think possibly there is a direction to electric current.

author: rpiloverbd
author_rank: Regular Contributor
timestamp: December 10, 2021, 12:57:55 pm
content: Owww, feeling sad or happy?

author: rsjsouza
author_rank: Super Contributor
timestamp: December 10, 2021, 01:40:48 pm
content: Welcome to the club!

author: Terry Bites
author_rank: Super Contributor
timestamp: December 10, 2021, 06:08:42 pm
content: Keep the homefires burning.

author: coppercone2
author_rank: Super Contributor
timestamp: December 10, 2021, 06:10:20 pm
content: buy yourself a big rheostat and tell us when you manage to burn out a 1kW circuit
Just finished the DSO 138 from JYETECH - Page 1
Forum section: electronics / beginners

author: Renegade
author_rank: Regular Contributor
timestamp: March 06, 2016, 04:44:57 am
content: Newb here - please be gentle.I just finished assembling theDSO 138 oscilloscope from JYETECH, and I'm pretty happy about it. I have the "K" model where you need to solder on all the SMDs.A few things have scared me off of using my Rigol DS1054Z with circuits that I power with my DIY benchtop power supply, and the DSO 138 is pretty much disposable, so it's given me a bit more confidence. I can use the DSO 138 first, and then use my Rigol without fear.Anyways... just wanted to share that.

author: Nomsot
author_rank: Contributor
timestamp: March 06, 2016, 01:29:12 pm
content: I want to see it) can you to show?

author: ledtester
author_rank: Super Contributor
timestamp: March 07, 2016, 05:59:52 am
content: What does your DIY power supply look like - pics / schematic?

author: RobertBG
author_rank: Regular Contributor
timestamp: March 07, 2016, 07:58:58 am
content: How did you like it?I thought it was a fun little kit myself.I'm waiting a few little things to finish it but I hacked mine into a old gameboy case.The screen was the perfect size and it fits really nice and it also made it into something I can carry and might actually use
Just found a good oscilloscope tutorial for Beginners! - Page 1
Forum section: electronics / beginners

author: jacklee
author_rank: Regular Contributor
timestamp: March 12, 2020, 02:59:46 am
content: I just got a message from youtube that Micsig just uploaded a few videos, it turns out a very good oscilloscope tutorial videos for beginners, so I recommend it as I also have a scope from them.Micsig Smart Oscilloscope Tutorial

author: StillTrying
author_rank: Super Contributor
timestamp: March 12, 2020, 06:47:55 pm
content: I think you'd have to be quite an expert with oscilloscopes to follow that.http://youtube.com/watch?v=GXbHnwIDQc8&list=PL4DPesFcepHs7DhG1IhxYm33MQGeeFHnw

author: rstofer
author_rank: Super Contributor
timestamp: March 12, 2020, 09:01:16 pm
content: There's a long video re: using an oscilloscope created by w2aew linked in the stickies at the top of this forumhttps://www.eevblog.com/forum/beginners/oscilloscope-training-class-(long)/

author: jacklee
author_rank: Regular Contributor
timestamp: March 17, 2020, 08:58:35 am
content: Just finished watching this video, not bad
just found this youtube chan on electronics and more. beginer and progresses. - Page 1
Forum section: electronics / beginners

author: whitevamp
author_rank: Regular Contributor
timestamp: June 19, 2017, 06:26:07 am
content: I was surfing around on youtube and came across this little gem of a chan and thought I would post it for all to look at.https://www.youtube.com/user/bigbadtechhe was or still is a teacher at CGCC : Columbia Gorge Community College.not affiliated with or anything like that.

author: Shock
author_rank: Super Contributor
timestamp: June 19, 2017, 10:31:22 am
content: Already been mentioned here:https://www.eevblog.com/forum/beginners/electronics-primers-course-material-and-books/There is also a list of other youtube channels here (it will be added whenez24gets around to it):https://www.eevblog.com/forum/other-blog-specific/dd/

author: Cliff Matthews
author_rank: Unknown
timestamp: June 19, 2017, 11:28:15 am
content: That channel has been on our pending list a while, but someone should gently tell Mr. professor his ugly green monotonous banner is one of the worst ever seen on YouTube. Actually, Brumby is working diligently on a program so we are not tripping over our shoe-laces repeating ourselves. Other issues are maximum post limits and automating the update of subscriber counts.

author: whitevamp
author_rank: Regular Contributor
timestamp: June 19, 2017, 01:34:25 pm
content: i thought that there was a youtube list of chans, but couldn't find it, in search.

author: Cliff Matthews
author_rank: Unknown
timestamp: June 19, 2017, 02:30:42 pm
content: Shock just gave it above.https://www.eevblog.com/forum/other-blog-specific/dd/. For channels not on the list, sorry but you'll have to skim-through subsequent submit postings in that thread.
just got an Agilent DSOX!  - Page 1
Forum section: electronics / beginners

author: awallin
author_rank: Frequent Contributor
timestamp: December 09, 2014, 05:42:12 pm
content: DSOX3034A arrived today. yay! US$ 3200 including delivery to Europe - figured that was reasonable - you only live once and all thatAre there any more Easter eggs than these?TREK screen-saver'matrix' style name-list under Utility / Options / 6-6-6-6etch-a-scope under Utility / Options / 5-5-5-5LOST countdown enabled by 16-23-42. Seems very boring from looking at Dave's video.Mine came with apparently original firmware, version 01.21.2011072803. There seemed to be a "dead" pixel (always blue) a bit down and left of center.After upgrading to the newest from the Keysight website (02.37.2014052001) this blue pixel is gone. Either it's a bug that is fixed, or they somehow detect bad pixels and turn them off?The hardware self test runs OK.On the front-panel self test, what is the "CAL" button - indicated between the soft-keys and CH1 input? I can't find it and I get 72 out of 73 keys tested.Any tips for hacking the scope? (I know there's a thread on that - just haven't had time to read it...)Any other tips?

author: awallin
author_rank: Frequent Contributor
timestamp: December 09, 2014, 06:11:32 pm
content: With prices like these for *software* upgrades methinks Agilent/Keysight deserves to be hacked...

author: DavidDLC
author_rank: Frequent Contributor
timestamp: December 09, 2014, 07:05:26 pm
content: Congratulations on your purchaseThe smoke on the icon is because now you realized the price on the licenses O0David.
Just learning - Page 1
Forum section: electronics / beginners

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: May 17, 2013, 12:29:04 am
content: I am going to order the book Make Electronics: Learn by Discovery by Charles Platt and I am starting to relearn everything I forgot and have not played with in a while ... I already have a bread board with wires and alot more ... But I was going to pick up up a couple 555 timer chips off ebay and is there anything else I should getOh by the way I am not going to buy the already built kits for those ridiculous prices when I can buy it for alot less on ebay

author: Falcon69
author_rank: Super Contributor
timestamp: May 17, 2013, 01:44:04 am
content: I learned my lesson about buying IC chips or anything especially static sensitive from eBay. most of the stuff you find on eBay or stuff that the manufactures has deemed out of spec and sold off for cheap. I ordered 100x ULN2003 chips off ebay, and over half of them were bad.Spend the little extra and save yourself a headache. buy from Digikey, Mouser, Newark, etc. when it comes to electronic components. You'll thank yourself later.

author: pickle9000
author_rank: Super Contributor
timestamp: May 17, 2013, 01:51:36 am
content: Tayda is a good place parts, get 40-50 bucks worth at a time if you can afford it. Better than Ebay at least>http://www.taydaelectronics.com/

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: May 20, 2013, 11:09:51 am
content: I am starting to put the kits for the projects and found I need a bunch of resistors but was thinking about buying a resistor kit from ebay but I am not sure whether to buy the 64 value metal film at 1% tolerance or to buy the 86 value carbon film resistors at 5%tolerance or just stick with mouser? Also I know I am going to have to put resistor together in order to make the right ohm rating..

author: minibutmany
author_rank: Regular Contributor
timestamp: May 20, 2013, 08:18:41 pm
content: If you are just doing a few small projects, you should get everything from mouser or digi-key. Ebay is good when you start designing your own stuff and need tons of different values on hand. As far as IC's go, 555,741 op amp, LM386 audio amp, and some 74 series logic are good. 2N3904 and 2N3906 transistors are great, get about 30 of each. Get a couple of voltage regulators to run your projects off of until you get a real bench PSU. Basically you should just find about five projects you want to try and get all the parts for those, when you are just starting its hard to know what parts you need if you have no specific area of interest.

author: blewisjr
author_rank: Frequent Contributor
timestamp: May 20, 2013, 08:56:28 pm
content: If you are in the us it may be worth going to amazon and do a search for Joe knows electronics. He has a 860 piece 1% metal film resistor kit for $20 and a 645 piece capacitor kit for the same price. Other then that I usually order from mouser unless adafruit has it cheaper. But as others said lots of parts. Can't count how many times on my current project I had to wait for something to come in.
Just OrderedMy Owon SDS7102 - Page 1
Forum section: electronics / beginners

author: tony3d
author_rank: Frequent Contributor
timestamp: November 27, 2013, 11:17:25 pm
content: Hi All I just ordered my Owon SDS7102 scope from Saelig. They seem to be excellent to deal with. I was just wondering If my unit will have the ground noise issue that I just found out has plagued this unit for some time now? Also, Can the battery remain in the unit all the time, or should it be removed if being powered by AC?
Just stopping in to say hi - Page 1
Forum section: electronics / beginners

author: HVAC_Walter
author_rank: Newbie
timestamp: October 09, 2022, 11:43:12 pm
content: I dont see a place for introducing my selfIm just here to learn as much as possible dont really think Ill be able to contribute much knowledge but im ready to learn

author: Nominal Animal
author_rank: Super Contributor
timestamp: October 10, 2022, 12:03:51 am
content: It is in the General Technical Chat section, the pinned (always at the top)New Member, Please introduce yourselfthread.

author: Terry Bites
author_rank: Super Contributor
timestamp: October 10, 2022, 10:10:07 am
content: Welcome to the blog friend.
Just to check with you guys, what capacitor is this? - Page 1
Forum section: electronics / beginners

author: SmallWalrus
author_rank: Contributor
timestamp: February 03, 2012, 04:17:11 am
content: Sorry for the newbie question, I figured that I probably am wrong, so I thought to post a picture of itThis is a 22pF capacitor right? However what does the g81 underneath it mean? And how do I find out the voltage for it?

author: metalphreak
author_rank: Frequent Contributor
timestamp: February 03, 2012, 06:44:40 am
content: That looks like a tantalum capacitor (since it has a polarity marking) and is most likely 22uF. Could also be one of those fancy SMD package electrolytic ones?g81 will be some kind of manufacturer code. Could be anything from a date/week code to tolerance specs to a batch number. Hard to tell without knowing which brand/model it is to look at the datasheet.22picofarads would normally be much smaller, like the size of those tiny brown/beige ceramic caps.

author: SmallWalrus
author_rank: Contributor
timestamp: February 03, 2012, 02:36:28 pm
content: Thanks for your replyHow do I find out what voltage it is though?

author: SmallWalrus
author_rank: Contributor
timestamp: February 03, 2012, 02:43:50 pm
content: Is there some guide on how to read these codes too? I've found 2 on Google and from what they said, it does seem like "220" is a 22pF value (as much as it might not make sense).

author: mariush
author_rank: Super Contributor
timestamp: February 03, 2012, 02:53:12 pm
content: 220 simply means 22 x 100= 22 ... uF , pF ... up to the size of the capacitor... at that size it's more likely to be 22uF, it's too large to be pF.821 would mean 82 x 101= 820uF etc etcas for the voltage... since they're near a chipset or some chip/controller etc... the voltages are probably around 0.8-1.8v so they're probably rated for 2-2.5v ... can't be sure without actually probing or without checking chips around the area (see maybe there's a switching voltage regulator and maybe you can determine the voltage based on its datasheet and surrounding parts)

author: Martin_bg1
author_rank: Newbie
timestamp: February 03, 2012, 04:24:57 pm
content: It is not possible to be pF cause it has polarity.About the voltage, if its possible turn it on and measure it .
Just Wanted to Say G'day! - Page 1
Forum section: electronics / beginners

author: wigman27
author_rank: Regular Contributor
timestamp: June 02, 2013, 11:52:11 am
content: Hi!As the subject says, I just wanted to say G'day, I'm Lee from Lithgow NSW. I have had an interest in electronics for a long time, sort of stemmed from my Dad really. I have almost finished my Advanced Diploma of Electrical Engineering and currently work designing high voltage overhead and underground power lines. Love it!.I look forward to talking to a lot of you, probably asking a lot but hopefully helping where I can.Talk soon I'm sure!Lee
jvc LT-43C700[A] - Page 1
Forum section: electronics / beginners

author: osmoticmole
author_rank: Newbie
timestamp: June 08, 2022, 03:39:09 pm
content: My 18 month old tv powers up, but turns itself off after a few seconds or a few minutes. Out of guarantee of course, but only 200 hours of use. JVC LT-43C700Any one with an idea if it's fixable?

author: m k
author_rank: Super Contributor
timestamp: June 13, 2022, 07:51:13 pm
content: Fixable or not it's too young.Guarantee shouldn't matter, it's a product liability issue.
K type thermocouple amplifier - Page 1
Forum section: electronics / beginners

author: mike_mike
author_rank: Super Contributor
timestamp: September 28, 2024, 10:05:09 pm
content: Hello! I have a K-type thermocouple and I want to build a cold junction thermocouple amplifier for this type of thermocouple.I don't have acces to specialized amplifiers, so I wanted to know if it is possible to build a thermocouple amplifier with cold junction compensation using discrete components.

author: magic
author_rank: Super Contributor
timestamp: September 29, 2024, 06:25:56 am
content: Not entirely sure about discrete, as thermocouples are all about small voltages and DC precision. You would need to ensure that your input stage is thermally coupled, well balanced and ideally has good PSRR.I know that UNI-T uses 1N4148 for temperature sensing and LM358 for amplification in some of their multimeters and that seems to be "good enough" for them.
K type thermocouple - Any suggestions? - Page 1
Forum section: electronics / beginners

author: ablacon64
author_rank: Frequent Contributor
timestamp: November 28, 2011, 01:56:54 am
content: Hi.I'm looking for an option for the K type thermocouple that comes in multimeters because they usually give a lot of difference in temperature measurement.I've seen some models on dealextreme:http://www.dealextreme.com/p/k-type-surface-temperature-probe-3933http://www.dealextreme.com/p/k-type-surface-temperature-probe-3934http://www.dealextreme.com/p/k-type-surface-temperature-probe-3923http://www.dealextreme.com/p/surface-temperature-probe-50-500-c-34206There's even a cheaper one that supports 350ºC that would be enough for me:http://www.dealextreme.com/p/flexible-high-temperature-probe-sensor-350-c-max-68454Anyone used one of those? Can you recommend an alternative? My main objective is to monitor motherboard temperature during a reflow operation.
K150 Programmer update - Page 1
Forum section: electronics / beginners

author: Savetheday
author_rank: Regular Contributor
timestamp: December 07, 2022, 10:41:30 pm
content: Hi everyone.I'm working on K150 (PIC16F628A) programmer. I have different PIC chips like PIC16F690 and PIC16F628A but I don't know how to set FUSES. How does it work?If I try to read and save an example chip, does it saves automatically FUSES information? I tried to program epk150.hex under the DIYpack25ep folder another PIC16F628A chip it gives eeprom error like this.Thanks.

author: mikerj
author_rank: Super Contributor
timestamp: December 08, 2022, 06:19:01 pm
content: This blog posts suggests a delay value in the programmer config file needs to be adjusted:http://electime.blogspot.com/2018/05/k150-pic-programmer-update-firmware.htmlProgramDelay=50 should be changed to ProgramDelay=70

author: Savetheday
author_rank: Regular Contributor
timestamp: December 08, 2022, 08:39:57 pm
content: voila it worked. Thanks.

author: mikerj
author_rank: Super Contributor
timestamp: December 09, 2022, 02:40:21 pm
content: Nice, glad it helped!

author: Savetheday
author_rank: Regular Contributor
timestamp: December 11, 2022, 02:14:04 pm
content: One last question I found a project that uses pic16F690 microcontroller on the project site I downloaded files they have different 2 .hex files and one .c file and .lay6 file. I thought I only need a file that is .hex file? If I try to program separately .hex files I get this error. "Received data error, About to apply reset.."

author: mikerj
author_rank: Super Contributor
timestamp: December 11, 2022, 10:23:58 pm
content: You should only need the hex file. The .c file is very likely the source code that gets compiled to create the hex file, and the .lay6 file is from a PCB design application called ABACOM Sprint Layout 6.The 16F690 has a very different pinout to the 16F627, and from what I can find the K150 does not support programming the 16F690 using the ZIF socket, you can only program it using in circuit programming cable. Is this what you are doing?

author: Savetheday
author_rank: Regular Contributor
timestamp: December 12, 2022, 07:52:18 am
content: oo now I know I was trying to program with ZIF socket.http://www.robotification.com/2007/09/16/program-a-pic-16f690-with-the-diy-kit-150-programmer/Thanks.
K8115 component tester - Page 1
Forum section: electronics / beginners

author: nForce
author_rank: Frequent Contributor
timestamp: October 06, 2019, 09:42:18 am
content: Is this an LCR meter:https://www.ebay.com/itm/Component-Tester-Kit-K8115/292644257716?epid=10006440206&hash=item4422f4ffb4:g:rJUAAOSwuLZbTc37Thanks.

author: teksturi
author_rank: Regular Contributor
timestamp: October 06, 2019, 09:49:48 am
content: I do not know for sure but it looks like cheap transistor/component testerhttps://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=transistor+tester&_sacat=0This looks like way too expensive. If you look lcr-meter look DE-5000. If you look component tester there are many threads in this forum.

author: Ian.M
author_rank: Super Contributor
timestamp: October 06, 2019, 10:43:05 am
content: Velleman product page:https://www.velleman.eu/products/view/?id=435470Astealat more than double CPC's price:https://cpc.farnell.com/velleman-sa/k8115/component-tester-kit/dp/MK00592Its certainly got basic LCR meter functionality, but is likely to be very limited compared to a modern digital LCR meter. It does do ESR, I don't know about ESL or Q. Compare its specs with the DE-5000 just mentioned:https://www.ietlabs.com/pdf/Datasheets/DE_5000.pdfOTOH if you *NEED* the semiconductor checking capabilities and you don't buy it from a rip-off Ebay scammer it may be worth it.N.B. If you have a Velleman HPS140MK2 handheld scope, it may be worth considering the HPS141 component tester accessory:https://www.velleman.eu/products/view/?id=435690which, (according to a Velleman staffer) shares the same base firmware and specs as the K8115. Its about 30% cheaper, fully assembled and also available from CPC:https://cpc.farnell.com/velleman-instruments/hps141/component-tester/dp/IN07745N.B. the HPS141 *ONLY* works with the HPS140MK2.

author: Canis Dirus Leidy
author_rank: Regular Contributor
timestamp: October 08, 2019, 12:47:27 am
content: Well… If you need just an LCR-meter: Chinese XJW01cost $65 on Aliexpress(Assembled variant. DIY kit without case costs half as much).P.S.Discussion on forum.DIY kit version review with photos of assembly and soldering order(in Russian).
K9PFG08U5M 32GB Flash USB hack? - Page 1
Forum section: electronics / beginners

author: themacman33
author_rank: Contributor
timestamp: July 27, 2014, 01:29:13 am
content: I salvaged 2 32GB flash chips from an old iPad. I feel like I should use these. Is there any way to use this as a 32GB flash drive? Can I graft it into an existing USB drive? I feel like I should try to use this big chunk of storage.Is there any way at all?Thanks, Mac

author: marshallh
author_rank: Unknown
timestamp: July 27, 2014, 01:35:01 am
content: Nope, not really.If you were super motivated you could source chips and the corresponding factory software tools from a company like Phison and make a custom pcb.These NAND chips require very complex controller chips to operate. You also can't splice them into another usb drive, the controller and memory are too tightly related.It used to be you could wire NANDs up to xD card readers, but those days are long gone.

author: amyk
author_rank: Super Contributor
timestamp: July 27, 2014, 08:04:30 am
content: The commands and interface for NAND flash are pretty standard and well-documented, so you should be able to hook it up to e.g. an Arduino (beware, this a 3.3V part) and be able to read/write it... but making effective use of the device i.e. bad block management/wear leveling will be the difficult part.

author: themacman33
author_rank: Contributor
timestamp: August 10, 2014, 04:39:42 pm
content: Ok, so is there any reason to keep them? I couldn't use them as general purpose storage for an AVR/PIC?

author: wraper
author_rank: Unknown
timestamp: August 10, 2014, 08:11:18 pm
content: Quote from: themacman33 on August 10, 2014, 04:39:42 pmIt would be much easier to just use microSD for that purpose.
KA3005P Included Software. Success with Window 7 install using USB interface? - Page 1
Forum section: electronics / beginners

author: swgertsch
author_rank: Contributor
timestamp: January 07, 2016, 07:36:39 am
content: Has anyone been successful getting the included software (on CDROM shipped with device) working under Windows 7, either in 32 or 64 bit versions of the OS?The included instructions are specific for Windows XP/2000. I have attempted to install the USB driver included on the CDROM without success. The KORAD application and NI (National Instruments) runtime library get installed but I cannot "connect" to the device to control it.Note: The install process installs what appears to be a generic "USB Virtual COM" driver versus the device specific "Nuvoton Virtual Com Port (COMn)" mentioned in the documentation.

author: tooki
author_rank: Super Contributor
timestamp: January 07, 2016, 05:13:05 pm
content: I was able to install it without issue into my Win7 virtual machine (64-bit). I don't recall having any trouble with it. (Was a couple of months ago.)Maybe try downloading from the net instead? I can't get the downloads tab on the product page on korad's site to work, but various vendors (e.g. SRA soldering) have the software hosted on their sites. And there's also a third party control program. The Web page is in German, but the software is in English. (Sorry I don't have the URLs handy, i'm posting from my ipad while googling on the computer.)
karnaugh map question - Page 1
Forum section: electronics / beginners

author: khatus
author_rank: Regular Contributor
timestamp: May 03, 2020, 07:57:17 pm
content: I can't understand how decimal designation differ by power of 2??

author: rstofer
author_rank: Super Contributor
timestamp: May 03, 2020, 09:26:11 pm
content: Look closely at the middle map. Note how the squares are numbered 0..3. That value is the binary value of the two bits concatenated as A|B. The upper left square is 00 so the value is 0. The upper right square is 01 so the value is 1.Now look at the combined squares 1 and 3. They differ by a power of 2 and in this case the power is 1. 21= 2The left map shows the case where the values vary by 1: squares 0 and 1 differ by 1 or 20.

author: Ian.M
author_rank: Super Contributor
timestamp: May 03, 2020, 09:34:19 pm
content: In other words, an over-complicated way of saying they differ by one binary bit . . . .That's the trouble with many textbooks where the author was paid by the word!

author: khatus
author_rank: Regular Contributor
timestamp: May 04, 2020, 05:50:52 am
content: Thanks😊
KBIC DC Motor Speed Control Adjustment - Page 1
Forum section: electronics / beginners

author: Larsson55
author_rank: Regular Contributor
timestamp: July 23, 2022, 04:23:54 am
content: I have this KBIC speed controller model KBLC-240DS and I want to adjust the trim pot where the P1, P2, P3 terminals are. Next to these terminals is an adjustment screw marked +12V Adjustments. The KBIC is plugged into 120VAC.What is the voltage in the P1,P2 P3 terminals? (I know I can use my meter but I don’t know if the volts are AC or DC and not very good using this meter)Thanks
KBMFxxSC6 - Page 1
Forum section: electronics / beginners

author: mianchen
author_rank: Regular Contributor
timestamp: December 01, 2013, 02:50:10 pm
content: I've got hundreds of these, anyone know what fun thing I can do with them apart from "practising" SOT-23 soldering or tossing in the binhttp://pdf.datasheetcatalog.com/datasheets/105/390476_DS.pdf

author: SeanB
author_rank: Super Contributor
timestamp: December 01, 2013, 02:56:47 pm
content: When designing using data like I2C use them if it goes off the board. Otherwise use them on digital inputs from pushbuttons or switches as a common protection plus pullup device. If you are using a analogue input run it through both switches in series and simply do not connect Vcc so it acts as a low pass input filter as well as an overvoltage protection.

author: mianchen
author_rank: Regular Contributor
timestamp: December 01, 2013, 03:27:00 pm
content: Quote from: SeanB on December 01, 2013, 02:56:47 pmcool, thanks. I'll keep them then.PS. If anyone want some, I can give them out for free (x20 per request?). Of course you have to cover the postage.
Keenetic 1 repair - Page 1
Forum section: electronics / beginners

author: u666sa
author_rank: Frequent Contributor
timestamp: September 05, 2023, 05:26:03 pm
content: 1. Pull off caps, checked with ESR meter, replaced a few just in case.2. Did CPU reball. (after reball, by hand, no stencil, BGA289 0.45 balls, 0.78 pitch... Anyway, after reball it did turn on once. Me happy ran to computer to flash some DD-WRT firmware onto it, but it did not fire back up)No clock signalI have another working router, swapped 40 mhz clock crystal from none working to working router, crystal is okey. I do get 40 Mhz clock on working router.On this dead one, there is no clock.What is reponsible for oscillating the crystal? Am I suppose to get voltage on it? Which way do I look into? Flash firmware chip or order new CPU? CPU is Ralink RT3052FI know this thing is old, and it's one of those cases throw it out and buy new one, but I'd really like to get this puppy working, as long as it's cheap. Because new router is about 20 dollars.

author: liaifat85
author_rank: Regular Contributor
timestamp: September 06, 2023, 10:54:53 am
content: Without any schematics, actually, it is quite difficult to figure out the problem. See if any part is getting hot after powering the board up. All perform a continuity test to find out if a short circuit has occurred somewhere.
Keep Circuit closed for a longer amount of time - Page 1
Forum section: electronics / beginners

author: martinjuhasz
author_rank: Newbie
timestamp: May 14, 2020, 01:11:14 pm
content: Hey,i have the following problem that i want to solve:I have a push button to open an outside door. As long as the push button is pressed, the door lock is in open state and people can walk through. As soon as the push button is released the lock disengages and the door is locked again. What i need is that after pushing that button, the door lock should stay open for a few more seconds so i can push that button, walk up to that door and go through.How it works:There go two wires to the pushbutton. As long as these two wires are connected, the door lock is in open state. These wires have 5V. Its not a direct connection to the door lock tho. The two wires come from some intercom system that handles all of this.What options do i have here? Is it possible to add some 555 timers or capacitors into the box where the pushbutton is to close the circuit a little longer? I have some more wires in that pushbutton box where i could serve 12V (sadly not 5V) and ground wires if needed.I appreciate any help and infos that point me in some direction so i can start reading and gaining some knowledge how to solve this.( sorry for this super bad image)

author: Manul
author_rank: Super Contributor
timestamp: May 14, 2020, 02:04:38 pm
content: If you short a push button with multimeter set to mA, how much current you get?Is one of the two wires going to the push button a ground or a +5V power supply of intercom? I mean, is it active low, or active high control?

author: martinjuhasz
author_rank: Newbie
timestamp: June 17, 2020, 01:21:31 pm
content: thank you for your answer. i tried different things in the meantime and coudn't find a really simple solution. so what i ended up with is a small IC that simply triggers the line for a specified amount of time. therefore i ran another wire with constant current to it.

author: eblc1388
author_rank: Frequent Contributor
timestamp: June 17, 2020, 02:39:25 pm
content: There is a pure mechanical solution.Search Google images for "Time Lag Switch". You can find a lot of pure mechanical hand operated push buttons which has a adjustable delay release timing of 10 seconds to 10 minutes. Be careful you select "Pneumatic" type instead of line voltage operated one. The timing is adjust via a screw, controlling the release of air once the button is pressed.

author: martinjuhasz
author_rank: Newbie
timestamp: June 17, 2020, 02:42:10 pm
content: That is cool! i did not know about these, thanks.
keeping batteries topped up - Page 1
Forum section: electronics / beginners

author: Raj
author_rank: Frequent Contributor
timestamp: February 18, 2019, 04:26:35 pm
content: If I had to store my batteries, and i could do that while having them connected to solar power to extend their life. Should I (is it beneficial)? And what technologies I should? And at what voltages?I know lead acid can be stored this way at 13.5v &I cant store lithium. What about nimh? nicd? etcI'm thinking of this mainly to extend lifes and have them ready for when they're needed.

author: Audioguru
author_rank: Super Contributor
timestamp: February 18, 2019, 06:14:45 pm
content: You should not and do not need to trickle charge Li-PO and Ni-MH batteries.Rechargeable lithium batteries that have cobalt and have a fully charged voltage of 4.20V per cell can be stored at 3.7V to 3.8V per cell for many years. I have the Lithium battery from my daughter's first cell phone that has been stored at 3.7V for 20 years and it still works fine. I store the Li-PO batteries for my RC airplanes at 3.7V per cell each winter.Ni-Cads are toxic and are obsolete. They also become weak or shorted.Ni-MH cells made within about 5 years can hold a charge for one year. You can top-them-up for a few minutes each year.

author: KL27x
author_rank: Super Contributor
timestamp: February 18, 2019, 10:41:04 pm
content: IIRC, Ni-Cads can be stored fully depleted. Just charge them before you intend to use them. This is how I always used them in practice, anyway, because they lose charge so fast.

author: Audioguru
author_rank: Super Contributor
timestamp: February 19, 2019, 03:44:55 pm
content: Ni-Cad batteries are very toxic and obsolete. Ni-MH has replaced them years ago. Ni-Cads shorted when they were discharged and shorted when trickle charged.

author: FrankE
author_rank: Regular Contributor
timestamp: February 19, 2019, 05:01:59 pm
content: You have charge controllers for each chemistry?

author: Audioguru
author_rank: Super Contributor
timestamp: February 20, 2019, 01:59:55 am
content: Quote from: FrankE on February 19, 2019, 05:01:59 pmOf course. Learn about battery chargers for all the different chemistries on the charger ICs datasheets and atwww.batteryuniversity.com.

author: grifftech
author_rank: Frequent Contributor
timestamp: February 22, 2019, 04:10:33 pm
content: ni-cd, nimh, and lead acid are less likely to explode/ignite when abused than lithium

author: Raj
author_rank: Frequent Contributor
timestamp: February 22, 2019, 06:23:02 pm
content: Thanks,That pretty much sums it up