Cracked inductors and shorts to ground...garmin dog training collars - Page 1
Forum section: electronics / beginners

author: Macroman
author_rank: Contributor
timestamp: September 12, 2022, 11:02:55 am
content: I ask that you keep in mind that I am a noob at this and it's a hobby of sort that I have started since retirement.I have several boards like this from my friend...The boards are out of garmin dog training collars for hunting dogs. (model#'s-- t5, tt10, tt15)They are powered by 3.7V Li-ion, 2,300-2,800mAh, 9.9Wh battery.These components are related to the audible tone and shock functions of these collars...and all have these same inductors that are bad. All the boards have 2 of these inductors (as shown in the 2nd image) and the related functions of the units are non-working on most of the boards with the damaged inductors.I have no real idea why the inductors are cracking, to be honest.The collars are strapped around dogs necks and the dogs fight huge wild hogs/boars (anywhere from 150-350 plus pounds) and are in a lot of swamp areas..lots of water. I am not seeing any moisture damage in the units though.I am guessing that the cracking of the inductors has something to do with the shocking part of the collar..maybe it over heats if shocking for too long..although the collar does have a 10 second auto shut off on the shock function. Not sure...but I do know that these inductors are damaged in every collar and that the shock/tone function no longer works in most of them that have the damaged inductors.The pcb board is fastened with 4 screws and 3 solder connections inside a waterproof housing...so I would think that it's not "rattling" around in there or anything like that.The chip near the inductors is SN9B019 (ID'd by someone on another forum as a multi-voltage power controller)IMG_7053IMG_7055Newer version of same model collar..Different looking coils but same damage and different numbers on the chip..IMG_7072Continuing with the garmin collars...Here is another TT10 everything working except shock and tone. I'm posting this also hoping that it may help others with these issues.Replaced the GPS module and collar will connect with handheld Alpha100 and able to track but the shock and tone functions are still not working.I found 4 components (capacitors) that are reading short to ground (marked with red marker), 1 on one side the board near the SN9B019 chip (multi-voltage power controller) and 3 more capacitors on the other side of the board.I see no cracks in the inductors on this board, like is seen on the other boards.Yet the same issue with the shock and tone functions..?? Hmmmmm?TT10_IMG_7349TT10_IMG_7352I have replaced the shorted capacitor from donor boards and some of the units will work after replacing the shorted capacitor...some will not.Are they repairable or should they just be a "no fix" and move on???What's your thoughts about it???Any help will be greatly appreciated.

author: Macroman
author_rank: Contributor
timestamp: September 12, 2022, 05:51:38 pm
content: Seems to me that joining the forum here and seeking help with a repair was a mistake..I get instantly derided for something that others are doing outside of my control..Instead of receiving help, instruction or encouragement.This is the very reason I and many other people, especially newbies/hobbyist are reluctant to post on forums.It is a childish behavior and reveals the true character of the user that makes such postings. It is really sad to ask for help and get this type of childish response. Grow up people!!! You never know who you are affecting and/or discouraging with this type of behavior.

author: Gyro
author_rank: Super Contributor
timestamp: September 12, 2022, 06:05:06 pm
content: Inductor cores crack due to mechanical shock and impact, they don't just shatter for electronic reasons, my response was technically accurate - what alternative explanation were you looking for?P.S. My apologies to the OP, it was just a gut reaction when reading of such practices. Different countries have different laws for such things.

author: wraper
author_rank: Unknown
timestamp: September 12, 2022, 06:07:19 pm
content: QuoteStrong mechanical impact. Inductors don't like that as they are quite heavy and fragile. MLCC fail for the same reason, they really don't like mechanical stress, especially PCB flexing.

author: Simon
author_rank: Unknown
timestamp: September 12, 2022, 06:41:33 pm
content: Well the OP is in America, some weird stuff is legal there. It sounds like the collars are not designed for the task, and that could mean they are unsafe.For you, a self proclaimed noob to be repairing such a device that would have (hopefully) been designated as a safety critical device and designed accordingly is not really a good idea. Substitute parts are a no no for safety critical equipment unless specified by the manufacturer.

author: Halcyon
author_rank: Unknown
timestamp: September 13, 2022, 06:29:46 am
content: Guys, I unlocked this thread as I personally don't see an issue with it.It's a legitimate device sold by a reputable company with legitimate uses (whether you agree with them or not). We aren't discussing illegal weapons here. Let's keep the discussion to the repair and electronics.

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2022, 06:44:15 am
content: Quote from: Macroman on September 12, 2022, 11:02:55 amWhat gear do you have ?Scopes, cap testers, SMD rework kit etc ?

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 10:28:56 am
content: Quote from: tautech on September 13, 2022, 06:44:15 amI only have a Kaiweets HT118A multimeter, a rework station (hot air and soldering iron), Andonstar AD409 digital microscope and a few other things...Just trying to learn as a retirement hobby to repair some personal items and help friends, so don't have a lot of gear.I will attach a pic of the area where the gear is.

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2022, 10:41:55 am
content: From the images posted in the OP it would seem the inductors have been changed/updated but as yet it’s unknown which might be the earlier version, Macroman can you possibly decipher any date codes from the PCB or IC’s to which inductor version might be later ?Also have you contacted Garmin for assistance ?

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 11:19:49 am
content: Quote from: tautech on September 13, 2022, 10:41:55 amtautech...from what I can see, the inductors in the 1st photo below are the older version.2nd photo is the newer version, these are on all the more recent collars.Units are out of warranty, so Garmin is of no help and of course they will not give out schematics or sell parts. New collars are $300 USD each, so my friend is trying to not have to buy new ones at this time.Maybe if can find a solution or repair it will also help someone else that need to save and extend the life of their investment.

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 11:21:52 am
content: Did some further trouble shooting and found that the 0402 component that the arrow is pointing to in the image below is shorted on all the units that I have tested so far.Replacing it with good ones from donor boards fixes the issue of the non-working tone/shock function of the collars.Also...some of the collars with cracked inductors work after replacing the 0402 component.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 13, 2022, 11:40:38 am
content: The component you are pointing to might well be an inductor and these have low impedance when measured with a DMM. So might not be broken at all.Edit: With a LCR meter you can determine the properties of the inductors from the working device and then try to source new ones with these properties.

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 11:49:17 am
content: Quote from: pcprogrammer on September 13, 2022, 11:40:38 amOkay..thankswhen doing troubleshooting, I found that when I desoldered that component, the unit will work with out that component even on the board. Also the faulty component test as shorted with Ohm test..but good units from donor boards do not test shorted, both faulty and good components were tested on and off the board.The component measures 1mm L x .5mm WMaybe it is a 0402 capacitor?

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2022, 12:04:23 pm
content: Quote from: Macroman on September 13, 2022, 11:49:17 amAn inductor is my preference but that don't make sense if you say it tests short.Old and new layouts appear the same circuit just laid out a bit different and black body and gold pads would have us thinking inductor.Maybe it needs a LCR test for a definitive answer on that one.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 13, 2022, 12:04:53 pm
content: That is a problem with SMD, hard to tell what is what. It depends on where it sits in the circuit, and it looks connected to ground on the one side and to a capacitor on the other side. But if the thing works without it and not with it then it will most likely not be an inductor, so could be a capacitor.Having a cheap LCR meter like here:https://aliexpress.com/item/1005001566461938.htmlcan help in determining components.

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 12:41:15 pm
content: Quote from: tautech on September 13, 2022, 12:04:23 pmQuote from: pcprogrammer on September 13, 2022, 12:04:53 pmThanks for the help and the link..I don't currently have an LCR meter (will try to get one). I just tested one of the shorted components that I removed from the board, in diode mode..it reads .003 volts (+/-), swapped the test leads (-/+) and it reads the same .003 volts.I'll include some screenshots of the component under my microscope..I know this probably wont help to ID the component but the image may be helpful in some other way.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 13, 2022, 12:49:04 pm
content: Indeed, does not really help in identifying it. Also no markings on it, so only a fully functioning one might provide a clue when measured.

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2022, 12:53:01 pm
content: Quote from: Macroman on September 13, 2022, 12:41:15 pmThe one pcprogrammer linked should do the job however if you are to continue to do SMD work I'd recommend you invest in some proper LCR smart tweezers which conveniently also give you ESR which is darn handy for rework and confirming what might look like an OK electrolytic is actually a dud.Member Shannon has been developing these with our help and they seem the best bang for buck in the dearer tweezers:https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/There are cheaper ones available that might be OK but the dirt cheap set I tried paled in comparison to my 15yr old ST-3's.

author: wraper
author_rank: Unknown
timestamp: September 13, 2022, 01:13:12 pm
content: Quote from: Macroman on September 13, 2022, 12:41:15 pmIt's a resistor. Should be low resistance one or 0 Ohm resistor which basically is a jumper, and you for some reason do not measure it in resistance mode. They do not fail short, they either fail open or sometimes resistance drifts, in 99% of cases to high side. So it should be completely fine. If you replace it with part which is not "short" (high resistance), you will break the circuit.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 13, 2022, 01:13:21 pm
content: I like to point one thing out here on safety. Even though the current won't be high, the voltage of the shock output might be and can be a problem when measuring on it. Since Macroman mentioned not having a scope no problem there, but just to be aware that it is the case when working on something like this.

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2022, 01:44:05 pm
content: Quote from: David Aurora on September 13, 2022, 01:29:59 pmWell a lifetime on the land and many hunts on pigs with my cousin and his tribe of dogs exposed me to another side of this than you might imagine.I've also seen working dogs run for miles without any means of stopping them after a belt from an electric fence, I've shot more dogs worrying stock than I care to remember and never I repeat never seen a dog abused with a shock collar however for all the dogs I've owned I never felt I couldn't control them without resorting to such tools however I never worked on properties that required 110% obedience from my dogs for fear they might chase, bail or worry anothers stock or some nontarget protected species.Many tools are used for non target species aversion and shock collars are just another tool to train a dog just like stock are trained to stay behind a wire.Again, we are not here to judge instead only fix broken electronics.

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 01:58:41 pm
content: Quote from: wraper on September 13, 2022, 01:13:12 pmOkay, thanks!!.....I have a question???I tested it in continuity mode and resistance mode (off board) and it reads shorted in continuity mode......So what does this mean?..if anything?

author: Macroman
author_rank: Contributor
timestamp: September 13, 2022, 02:11:21 pm
content: I want toThank All those that are helpingto solve the issue and possibly lead to a repair.

author: wraper
author_rank: Unknown
timestamp: September 13, 2022, 02:14:10 pm
content: Quote from: Macroman on September 13, 2022, 01:58:41 pmIt just beeps when resistance is below certain threshold, usually a few tens of ohms. Sometimes helps doing measurements without looking on display.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 13, 2022, 03:35:25 pm
content: In resistance mode you measure the ohms value of the component and then it depends on what it can measure what you will see. But don't forget that your test leads have resistance also. In continuity or diode test mode it measures more or less also the resistance, but when below a certain value it will also beep. This is very handy when reverse engineering a schematic. You can hear if you are on the right trace.For a diode under test it shows the forward voltage if the polarity is the right way round.

author: wraper
author_rank: Unknown
timestamp: September 13, 2022, 06:12:22 pm
content: Quote from: pcprogrammer on September 13, 2022, 03:35:25 pmIn diode mode it measures voltage drop at certain small current that meter provides. So it's not really a resistance that meter shows. Some cheap meters combine continuity mode with diode mode, and then you don't really see actual resistance in that beeper mode. But on vast majority of multimeters, including the meter OP has, it's just a beeper added to a low resistance range (autotrange disabled) of resistance mode

author: Simon
author_rank: Unknown
timestamp: September 13, 2022, 07:17:19 pm
content: Quote from: wraper on September 13, 2022, 01:13:12 pm

author: Halcyon
author_rank: Unknown
timestamp: September 13, 2022, 10:23:26 pm
content: As I said in my last post, keep your own personal beliefs and morals out of this discussion, this is about electronics repair. I'd accept comments if you happen to be some kind of expert in animals or animal behaviour, but even then it's off-topic. I have a soft spot for animals too, especially dogs, however this is one area I know nothing about so I'm leaving it well enough alone. We are here to moderate as fairly and equally as possible.I will simply start deleting posts if they aren't related to repair.

author: Halcyon
author_rank: Unknown
timestamp: September 13, 2022, 11:13:17 pm
content: Since some peoplestilldon't get the message, I've removed all non-repair related posts (from both view points) from this thread.Unless your post relates specifically to helping the OP repair his device, do not post.

author: David Aurora
author_rank: Frequent Contributor
timestamp: September 13, 2022, 11:19:54 pm
content: Quote from: Halcyon on September 13, 2022, 11:13:17 pmNo, I got your message, I'm just really disappointed that the official vibe here is to gloss over animal abuse (and actively delete any posts calling it out) as long as the post mentions an electronic component. Pretty slippery slope ethically.

author: EEVblog
author_rank: Unknown
timestamp: September 13, 2022, 11:45:42 pm
content: Everyone, a reminder that this is theBeginnersection. A newbie came here asking for technical help and it seems got hammered with criticism.The original post is as close to a basic technical repair help question as you can get, please leave the politics out of it.

author: EEVblog
author_rank: Unknown
timestamp: September 13, 2022, 11:47:18 pm
content: Quote from: David Aurora on September 13, 2022, 11:19:54 pmGo and abuse Garmin for selling it then, this is not the place to attack someone for asking for technical repair help on an electronics forum in the beginner section.

author: Halcyon
author_rank: Unknown
timestamp: September 14, 2022, 12:18:43 am
content: Quote from: David Aurora on September 13, 2022, 11:19:54 pmSo you just chose to ignore me?No one, including the OP is promoting animal abuse. You'll also notice that I deleted off-topic posts of the opposite view (like I said I would). I wasn't just selectively cherry-picking posts.You and everyone else are entitled to your opinions, whether they are well-founded or not, but there is a time and place for voicing them (this is not the place). I just don't understand the compulsive need for some people to shove their thoughts and opinions down everyone else's throat. You won't change their mind and it only serves to upset others and de-rail a perfectly legitimate thread.Ethically, I think we've done the right thing by not taking a stance one way or another. You and I are not here to "educate" people on ethics and morals, particularly when it's not our area of expertise. If you don't like or agree with the subject matter, then don't read or participate in the thread, it's really that simple.Or... to put it in simpler terms: Don't be a dick.

author: EEVblog
author_rank: Unknown
timestamp: September 14, 2022, 03:46:15 am
content: I'll repost the "rules" so the speak for the Beginners section. Note the last part.

author: Siwastaja
author_rank: Super Contributor
timestamp: September 14, 2022, 02:03:54 pm
content: With mechanical failures, careful visual inspection gets you far, no need to measure every component electrically.MLCCs (ceramic capacitors) can fail without obvious visual clues, but they fail as short circuits (or very nearly so, low resistance like just a few ohm). You can usually test them in-circuit with a multimeter in resistance or diode mode. Capacitors (especially large value ones) will shortly read as nearly short circuits as they charge up, this is normal. But if the value stays low, then it's shorted. Also when measured in-circuit, other parts of circuit interact with the measurement, but if the diode mode reads very low voltage like below <0.1V and does that in both directions (+ and - probes swapped), then the capacitor is very likely shorted.I wouldn't bother measuring resistors and inductors if they look visually perfect.Solder joints can also fail, again visual inspection works.A good microscope is one of the best instruments when trying to fix broken things, commercial or your own prototypes. After assembling a prototype, I now routinely spend 15-30 minutes scanning through the whole board in different angles under a microsscope, saves hours of time trying to find the few defects through testing.

author: Macroman
author_rank: Contributor
timestamp: September 14, 2022, 06:10:53 pm
content: Quote from: Siwastaja on September 14, 2022, 02:03:54 pmThank you for the help and informational instructions!!!I do have a Andonstar AD409 microscope and I have tried very hard to inspect the board on both sides in it's entirety.I did find some shorted components when tested in continuity mode. I am going to do some more testing like you suggested and see what I find.I am learning a lot while trouble shooting and even got one board working and fully functional once again.So I feel that the time I've spent has been educational and really interesting so far.Thanks again!!

author: tautech
author_rank: Super Contributor
timestamp: September 14, 2022, 08:45:56 pm
content: Have you tried swapping out the SN9B019 ?I'm trying to find time to hunt for the datasheet for it as quite often a typical application circuit has a circuit values too often copied exactly by the end product manufacturer. Using this method when sorting circuits can save immeasurable time and effort.

author: Macroman
author_rank: Contributor
timestamp: September 14, 2022, 09:40:28 pm
content: Quote from: tautech on September 14, 2022, 08:45:56 pmI have thought about swapping it but not tried that yet..But have found that the SN9B019 chip seems to be "custom numbered" for Garmin, so not sure if could find a replacement....I'm thinking it would have to be a one from a donor board.

author: tautech
author_rank: Super Contributor
timestamp: September 14, 2022, 09:51:44 pm
content: Quote from: Macroman on September 14, 2022, 09:40:28 pmYet if we Gurgle that IC we can find sources for them which then I normally start looking to see if they have a link to the datasheet. I've often found obscure datasheets this way.

author: Macroman
author_rank: Contributor
timestamp: September 14, 2022, 09:56:15 pm
content: Quote from: tautech on September 14, 2022, 09:51:44 pmOh okay....being a beginner, I did not know this...Thank you for sharing your skill and info..It is much appreciated.

author: tautech
author_rank: Super Contributor
timestamp: September 14, 2022, 10:10:27 pm
content: Quote from: Macroman on September 14, 2022, 09:56:15 pmSo so often the datasheet typical application circuit can clear up any assumptions of how a circuit works and the supporting component values used are so often in black and white ! The rest is up to you to work out what's actually happening when it's running correctly and being able to take measurements in one that isn't operating and deduce with part of it is busted.I suspect the ferrite bobbins are getting cooked and becoming brittle but how and why is the matter of debate OR as there have been a change of inductors they are not holding up to normal use, whatever normal might be for your buddy.Does he hunt in heavily wooded terrain as a dog colliding with a tree trunk could certainly impose sufficient physical shock to a collar to break anything delicate inside.Here it's wise to think outside the square some as the cause of faults might not be anything like we think.

author: Macroman
author_rank: Contributor
timestamp: September 14, 2022, 11:58:50 pm
content: Quote from: tautech on September 14, 2022, 10:10:27 pmAh..more good helpful info!!..I have pretty good troubleshooting skills for many things but have never tackled electronics until now. I had a side business for several years working on small engines and in my shop I had a 1940's Atlas metal lathe that I bought and restored and used it a good bit for making odd parts etc. also had a small milling setup for very small stuff, I am good enough at aluminum tig welding for people in this area to ask me to weld their boats or other aluminum items that need welding and i also mig and stick weld also for over 20 years now, made knives as a hobby for a few years also...I have "dabbled" in a lot of things over the past 40 to 45 years. Growing up on a farm, I learned to work on all sorts of things but never had many electronic circuits to learn about.That's a reasonable and possible scenario that you have about the ferrite getting cooked and becoming brittle...someone else suggested that "if the dog is wet the shock will bypass the dog and go through the water - at much higher current. it could be overloading the high voltage generator."...I guess that could be happening also...I do know that the shock part has an auto 10 second cut off.There seems to be something causing the overheating/cracking of the inductors because its the same in old and new versions and the same components are the ones that test as shorted on 99 percent of the units.Yes...they hunt in all types of environments, mostly wooded and/or swampy areas..the swamps have a lot of Cypress trees and they grow what is called "knees" up from the ground off the roots that stick up anywhere from a couple inches tall too 1.5 feet or more...and the dogs collide with them a lot.You can see the "knees" sticking out of the ground/water in the reference image below of one of my stepsons...impact with those hard roots causes quite a lick...I have fallen on them while walking in areas like that and had bruises for a couple weeks..really painful. So it would be a hard impact if a dog collides with it while running at full or even half speed.Also these dogs wear kevlar vest to protect their body from the hogs razor sharp tusk..the dogs are at times thrown fiercely by the hogs when they slam their heads into the dogs to try and cut them with the tusk..So there is a huge "square" in which this issue could be caused by or coming from.I am taking notes and going to try different things to attempt to come up with a solution with the help of you and the others here.Thanks again to you and all the other helpful users here for your insight and sharing of your knowledge..I really appreciate it.This type of issue is good exercise for the old brain..that's for sure.

author: tautech
author_rank: Super Contributor
timestamp: September 15, 2022, 12:21:34 am
content: Quote from: Macroman on September 14, 2022, 11:58:50 pmWe have so much in common. Rural background and still here, carpenter, 5 years in small motors then 40 years back on the land and youngest son runs the place now but I still get called on for the workshop skills he's yet to develop.Quote100% and I'm now thinking impacts are the cause rather than having been overheated at any stage.Check the enclosures for rigidity and if there's insufficient clearance from case to the PCB as a good belt against a tree with the weight of a dog behind it will certainly smash them ferrites.Take a mo to also think why Garmin had changed them ferrites....to a more robust version ?QuoteSome use vests here but most don't but are very selective to breed dogs with some brains for them to avoid getting another poke after a first one they might get on smaller pigs rather than some old bruiser that rips a knucklehead dog apart on the first encounter.QuoteYep for sure and it's a daily occurrence for me fitting the 'right' product to a customer to know they'll be satisfied with it.

author: Macroman
author_rank: Contributor
timestamp: September 17, 2022, 11:44:13 am
content: Quote from: tautech on September 15, 2022, 12:21:34 amThanks for all your help. It is much appreciated.After the recommendations from users here and then looking into it more, I decided to order an LCR meter.Waiting on the LCR meter to be delivered, then I will do some more testing on the components and trouble shooting the boards.I've ordered this one shown below,....from what I have read and watched in YT videos, it should work well.

author: Macroman
author_rank: Contributor
timestamp: October 23, 2022, 05:16:21 pm
content: Quote from: tautech on September 15, 2022, 12:21:34 amDid some more testing and found that there is a BJT-NPN transistor on the board that is not testing correctly..BUT when desoldered from the board and tested out of circuit it test as good...Any suggestions or ideas?

author: Simon
author_rank: Unknown
timestamp: October 23, 2022, 05:52:28 pm
content: Quote from: Macroman on October 23, 2022, 05:16:21 pmJust to get this straight, you expect to test a BJT in circuit and see it test out in the same way as it would as a new part? Like trying to measure resistors and capacitors in circuit?You can't do this, when you try to measure a component in circuit you are measuring that component and the entire circuit. Of course it will not work, this is why repairing is challenging, I have ditched boards of my own as trouble shooting was not possible despite me knowing the design as it would be so time consuming that it was faster to build a new PCBA.

author: Macroman
author_rank: Contributor
timestamp: October 23, 2022, 06:30:57 pm
content: Quote from: Simon on October 23, 2022, 05:52:28 pmYou are really set on discouraging the repair of this unit because you have a personal problem with what it is..You have been warned previously but evidently you are too foolish to act with any type of common sense and respect..How someone like you is a mod here is really disturbing.

author: wraper
author_rank: Unknown
timestamp: October 23, 2022, 06:36:54 pm
content: Quote from: Simon on October 23, 2022, 05:52:28 pmWell, it sort of works. But you need understanding why you may be getting particular measurements if they are not the same as bare part. And if off reading is something worth to be investigated further. For example you can measure resistors as long as measurement voltage is low enough to not affect semiconductors. If you get lower reading than nominal, most likely it's fine. But higher reading is most likely not OK unless there is some charged cap which hinders the measurement. Capacitor ESR is not a problem in most cases if you have a suitable meter which measures at AC, and not some super cheap jobbie which measures charging/discharging times and derives something from that. Of course you should consider there can be several caps in parallel on power rail. You can test BJT in diode mode mode, and figure out if some junction is short or open. If you get suspicious results, then desolder the part and check out of circuit.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 23, 2022, 07:05:11 pm
content: Like what wrapper wrote. The tester you have is not suited for in circuit testing. I normally use a digital multi meter in diode mode to test junctions on a short, but this is not fool proof.The fact that out of circuit the transistor seems to be ok means you have to look at the part of the circuit the transistor sits in and try to determine what it does, and if it is indeed a part of the problem.Things like these are always difficult, especially from the side line without having access to the PCB or a schematic.

author: Macroman
author_rank: Contributor
timestamp: October 23, 2022, 07:20:18 pm
content: Quote from: pcprogrammer on October 23, 2022, 07:05:11 pmIf you look at the third image that I posted, you would see that I tested the component with a multimeter. (that image reposted in this reply)

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 23, 2022, 07:29:19 pm
content: So you did. My bad for not fully checking your post.But what I noticed is that for the base emitter measurement there is some component below the transistor connected between the base and the emitter. This can be the reason for the low value you got there.Like I wrote it is hard to say what is wrong without a schematic.Edit: By the looks of it the transistor is driving a coil of some kind. Do you have as scope to measure what is on the base of the transistor?Did you identify the transistor?Sorry if asked before but its been a while and I don't want to reread the whole thread. Also my bed time, so signing off.

author: tautech
author_rank: Super Contributor
timestamp: October 23, 2022, 07:48:40 pm
content: Quote from: Macroman on October 23, 2022, 06:30:57 pmWhoah back, Simon is only showing his experience in repairs and testing components and of his comments I agree 100%.Don't take it personal.

author: Simon
author_rank: Unknown
timestamp: October 23, 2022, 08:18:05 pm
content: Quote from: Macroman on October 23, 2022, 06:30:57 pmI am afraid that no one has warned me about anything! There are users that think they carry weight here, they are gravely mistaken. YOU sir are the one looking for an argument. I have just told you something that is true but because it contradicts what you hoped to do you are throwing accusations at me. It is a fact that you cannot "test" a part in circuit and expect it to behave as it would if you tested the part on it's own, I am sorry to break reality to you. it is the same for any part. Perhaps you can explain why you would expect a part to check out in a circuit as it would not in the circuit. If you can't take advice then don't ask. You don't have that much experience and your assumption is a common mistake of a beginner like you.

author: Macroman
author_rank: Contributor
timestamp: October 23, 2022, 09:56:25 pm
content: Quote from: Simon on October 23, 2022, 08:18:05 pmI came here asking for technical help and I got criticism for even attempting to fix something that you think is "out of my league" because I am a noob...You sir are the one that started the argument.You have no knowledge of my learning abilities, my tools that I have available or my years of experience repairing other items that may be useful in this situation.Instead of trying to help a noob learn and posting a method of further testing...You immediately made a post belittling and demeaning me with your "I'm better than you attitude"...All you know how to do is act like I am beneath you and don't have the ability to learn or try to repair something becauseyou don't thinkI am capable...Well..you know...the people that think like you are the same type that sent Albert Einstein home to his mother with a note that said he was retarded.It's people like you that discourage others from trying and wanting to pursue a hobby or even a career in electronics...

author: tautech
author_rank: Super Contributor
timestamp: October 23, 2022, 10:43:45 pm
content: Macroman, please don't poke the bear and if you continue to you will be gone.

author: Macroman
author_rank: Contributor
timestamp: October 24, 2022, 12:23:29 am
content: Quote from: tautech on October 23, 2022, 10:43:45 pmYou and a few others here have helped me..I greatly appreciate it.On the other hand...I was not welcome here from the start by Simon and many others...I waited awhile and debated on even posting here again and when I did...He begins his same belittling attitude crap.Be damned, if I am going to tolerate this sort of thing every time I come here to make a post.Let them ban me...it has not proved to be a very welcoming or enjoyable forum to be a part of anyway.

author: EEVblog
author_rank: Unknown
timestamp: October 24, 2022, 02:39:49 am
content: Quote from: tautech on October 23, 2022, 07:48:40 pmYes, this is silly.Simon is absolutely spot on and is his reply above that caused to you to take offence is the most innocuous post I can imagine. Why take offence at this?

author: james_s
author_rank: Super Contributor
timestamp: October 24, 2022, 04:59:39 am
content: Quote from: Macroman on October 23, 2022, 06:30:57 pmInitially he did, but that is water under the bridge. In this post he is spot on, he's telling you a simple technological fact, you cannot expect a component to test in-circuit the same way as it tests out of circuit. This may be an inconvenient fact, it has caused me difficulty many times, but it is none the less still a fact. Testing parts in-circuit is not straightforward and requires knowledge of the specific circuit in which they are used. I have absolutely no moral objection to dog training collars and I'm telling you the same thing Simon did, that you can't expect a component tester to reliably test parts that are installed in a circuit.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 24, 2022, 05:16:34 am
content: Even though Simon is right, I can see why Macroman felt it the way he did. The way Simon wrote it has some condescending tone in it, and the history of this thread is indeed not the friendliest one.But there are people here willing to help. So Macroman if you still want it, just provide additional information. But be aware that our clocks run on different times with this big puddle of water between us.

author: tautech
author_rank: Super Contributor
timestamp: October 24, 2022, 05:54:13 am
content: Quote from: Macroman on October 24, 2022, 12:23:29 amReally you need take a step back and realize others don't have the outdoor/rural experience we are lucky to have so see particularly the blood sports as extremely distasteful whereas you and I know they are just a part of rural life and for many.Just that alone got them off on the wrong foot with you but with care we have them realize it's not as abhorrent as they might imagine yet you seem to have not cut them much slack.Sure Simon may have been a little more gentle however it's common knowledge you'll have trouble obtaining sensible measurements of most components in circuit.You initially indicated you might struggle with this repair but apart from todays diversion it seems you are working through things just fine as anything SMD is normally a bit of a challenge.Hang in there, stay on track and bring anything to us that's brickwalling you.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 24, 2022, 10:06:31 am
content: to beginner OP... let me suggest further, an oscilloscope, so you can see signal going into the transistor (if its ok tested outside circuit) maybe the damage is somewhere else such as bricked mcu? or broken (open) resistor? oscilloscope can help further in diagnostics. btw where is our good mod deleting off topic posts in this thread? i would like to see that happening... whoever dont follow this thread since beginning (before posts deleted) dont have clues. there still useless posts remain in first page to get the hint. sometime a helpfull post can have negative tone in it that can cause negative feeling to easily offended people. for example if you see a mentally ill person on the street and you know he has a gun and he will pull his gun out even if people try to reason with him rationally, you may choose to ignore him, let him do what he like.

author: Simon
author_rank: Unknown
timestamp: October 24, 2022, 07:43:03 pm
content: Quote from: tautech on October 24, 2022, 05:54:13 amI don't have a problem with the devices if they have a legitimate use. I don't know what the design considerations are but I'd sort of assume that there are some safety considerations, maybe not as much as with devices for people but I'd sort of expect some caution in repairing them. I'm sorry but I don't see much consideration to these repairs, just make em work any old how.Having said that in my last job I'd have quite earlier than I did if I could have, given the consideration (lack of) given to the design of what to me amounted to a life support system. I think that the assumption was the systems would never get used if we all just stuck to the conventions of war so it didn't matter. Syria's leader showed that the use of our equipment was likely to be more real than hypothetical.I've always had a knack of knowing when I am out of my depth.....

author: tautech
author_rank: Super Contributor
timestamp: October 24, 2022, 08:00:26 pm
content: Quote from: Simon on October 24, 2022, 07:43:03 pmYes however in repairs especially is the lure that man made it so man can fix it and this challenge drives us forward to gain more/better knowledge.For a hobbyist a successful repair is an achievement whereas for the professional or repair shop it's just another day and the hobbyist places less value on time invested as it is also schooling.As time goes by we as hobbyists discover our tool suite is not always up to the task and especially so with SMD so further investment is required to make proper progress after we teach ourselves to use it on scrap boards.Rework stations, SMD tweezers are just a couple and for the better ones a $500+ investment is required, all of which takes time and commitment to fund.Meaningful progress can be painfully slow ............

author: Simon
author_rank: Unknown
timestamp: October 24, 2022, 09:19:14 pm
content: Quote from: tautech on October 24, 2022, 08:00:26 pmRepair and design are two different areas. Dave once did a video on this, he was particularly talented at repairing one piece of kit, but at the time would probably not been able to design one. Repairs are often done on the basis of a known fault to be common in a particular product and experience of that one item. My limited experience of repairs is that I'm either not good or that many things are just too much work, OK if you do it for fun that's not dollars to hours but professionally we hit a point where repairs are often not worth the time. This is why I take part in my local repair cafe, we do it for fun in the hope of saving things from landfill but I will not carry out repairs that are going to take days so many electronic devices get tossed as simply probing around blind and with no knowledge of how it works is pointless. So a full stereo system was junked, sure I know exactly what was wrong with it, a capacitor..... somewhere, I checked out the power supply section and had to say, sorry, I don't have the time to take every cap off and check it. Last week a radio came in, no sign of life, I got as far as establishing that the power worked but in the half hour slot we give people a 1980's radio was never getting fixed.One of our volunteers seems to think he knows all about electronics because he knows ohms law, yep, according to him that is all you need (well technically if you have the brain of a computer you could derive all the other math on the fly....), needless to say he probably has learning difficulties and we won't let him work on anything live.

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 24, 2022, 09:24:48 pm
content: Quote from: Macroman on September 12, 2022, 05:51:38 pmYou message is not edited, so excuse me but, what?You were complaining already while absolutely nobody had answered yet?What did I miss?

author: Gyro
author_rank: Super Contributor
timestamp: October 24, 2022, 09:54:06 pm
content: Quote from: DavidAlfa on October 24, 2022, 09:24:48 pmYou missed my (I thought) fairly innocuous two line reply, since deleted by the mods, that...1. the inductors probably wouldn't break if not subjected to such impacts, and2. (a little more controversially) thatnow thatas function was now restricted to location, they were now operating optimally in my opinion.I must admit that I didn't expect the explosion that followed. I did apologise to the OP however.

author: tautech
author_rank: Super Contributor
timestamp: October 24, 2022, 09:57:38 pm
content: Quote from: Simon on October 24, 2022, 09:19:14 pmCertainly but we gain knowledge about how things work and how they are put together by doing repairs.Then we might even be tempted to build our own boards and in doing so not repeat the mistakes on PCB's in some POS that was designed with zero consideration to rework.As you well know there is so so much to learn which is why EEVblog is so successful by sharing the knowledge we have all gained in our pursuits, be they in the professional or hobbyist arena.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 25, 2022, 04:29:57 am
content: And in the meantime Macroman has left the building.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 25, 2022, 09:48:18 am
content: Quote from: pcprogrammer on October 25, 2022, 04:29:57 amor maybe he realized too soon that doing is better than asking in forum.. forum only for bashing and having fun...

author: Simon
author_rank: Unknown
timestamp: October 25, 2022, 09:15:50 pm
content: Quote from: Mechatrommer on October 25, 2022, 09:48:18 amNot really, but when you see the rational people put in, you can see from the start whether or not they are serious enough or have the aptitude to learn. Most of what I learnt came from this forum or other informal teachings, what little I learnt from formal education would not fill this forums allowable signature char length.