probably a very expensive bit of kit in the day. I just bought a timing light with dial back from amazon for about £35 - although only with an LED for the strobe, but does the job and matches my mates expensive snap on light that i had to keep borrowing.
Beautiful fix on a strange fault, but you seem to have found the mystery! As usual I'm impressed! Thank you so much for all those precious informations!
In 45 years as an electronics hobbyist, and 40 years as a professional electronics service engineer / electrician, I have NEVER come across this fault with a diode, and I've tested 1000s over the decades in my career. This is one of those, once in lifetime moments that you rarely see in real time. The closest I had to this was a high resistance fuse that stopped a UHF transmitter from working when I was in the Royal Navy, it had a resistance of a few Ohms only, and bleeped with a multimeter on continuity bleeper mode, but those few Ohms were enough to cause the fault. We had been going round in circles for ages trying to fault-find that transmitter.
Yes I thought it was quite a rare occurrence. I had an odd fault like this with a Milwaukee vacuum where the fuse was passing voltage but no current (video is on here too).👍
@@BuyitFixit If you can measure a voltage, but you can't draw current, that is a sign that there is a high resistance between the source of the voltage, and where you are measuring. I work on diesel engines in my work, and I have 12 Volt 21 Watt auto lamp wrapped in foam so it doesn't break, connected to a couple of wires, one with an alligator clip to connect to earth / chassis of the machine, and the other wire I made a sharp probe out of a piece of welding rod. If there is a bad connection in the 12 Volt system of the engine, the lamp will not light, or it will be dim. If you measure the same point with a multimeter, it will show 12 Volts or more, giving you the false impression that there is ''power'' there. There isn't ''power'' there. Only voltage. It's our old friend Ohms Law that causes this, and the fact that a multimeter, on voltage, is a resistor of about 20 Megohms when connected to the circuit to measure voltage. A 21 Watt lamp is a resistor less than 2 Ohms when connected to the 12 -14 Volts of an auto electrical system. This is one of the most valuable things to consider when fault-finding 12 or 24 Volt auto electrical systems IMHO.
Great video - Thank you. I saw the date and time displayed on the scope. It showed 01:00. I just figured you haven't set the time up. Then later you said it was 02:00 and dark so no chance of trying the test on the log splitter. Kudos to you for not only being a great repairer but also a night 🦉🙂
@@BuyitFixit bit of 'tweek' ~ *HAIL* _not just Warrior,_ but *mighty Knight.* Nice to hear Farm Animals from time to time; Hope all's well there. *Cheers!*
I remember small signal transistors BC 108, BC 109 etc go noisy with heat and clear with a shot of freezer way back in 70’s ! Brilliant fault finding video ! Keep them coming! Retired technician, Fraser ,😊
Mr Carlstons Lab has brilliant signal tracer design with non contact probe just for ferreting out noisy components like semiconductors, resisters etc ! Works up to rf and doesn’t load the circuit it’s testing! Details all on his site and you can build it very cheaply ! Cheers Fraser⚡️
Buck Rogers could use that in the 21st Century....😄 Glad to see you were able to fix a substantial piece of equipment like that. My dad use to have a metal Timing Gun as well. Different design but very well made.
More than likely the rheostat is to test total timing advance, you zero it out race the engine than turn it until the timing mark lines up again and it should display the total ignition timing advance.
These type of timing lights were quite common back in the day of breaker point ignition systems with an adjustable distributor. After speeding up the engine the knob was rotated till the flashing strobe light came back to the stationary mark. The "total advance" was then read on the digital display, typically no more than 40 degrees if that much. Someone who can troubleshoot/fix down to the component level is as rare as this timing light!
That was a good fix Mick! I once found an open circuit diode that had a leg that would twist around in it's socket. (Obviously it was only possible to spot once I had de-soldered it.)
Had a couple of diodes be Open (usually short is the failure mode like you said)but not caught one like this on the verge/able to recover with heat. Definitely had other components that behaved after heating though.
I've never seen one do that before, probably a testament to cheap parts bought in bulk from the lowest bidder. Having said that I probably would have just replaced it when I observed the open circuit without going any deeper.
Me either. I've had stuff read weird in circuit before, especially if there's charge in a capacitor for instance. Sometimes you get minus ohms etc, so I wasn't sure if it was something else affecting the reading (I've never seen it before on a diode) but when it measured OK out of circuit..
Some where,in my computerized yard,I have the same thing,which I bought 40 + years ago,when cars had points,wow was it that long ago,good video,thanks.
I had a faulty diode with the same problem in a car computer module I was repairing the other day. It was an IN4004 diode. The computer had a few capacitors blown after replacing them I still had no 5volt supply to the MCU. Checked the diodes around the MCU and found and open diode. Removed it and it checked good so apparently the heat of the iron expanded it enough to make internal contact. Replaced the diode and the car was up and running. This must be a common problem. Keep some freeze spray in stock it’s great for finding stuff like this.
I've never seen a through hole diode do that before. The reason that chip looked like it was already changed is because that was the only component on that side of the pcb, so it would have gone through a flow solder machine to do everything and then after that would be done by hand.
I once had a 2n222 transistor that measured fine when cold but went open circuit shortly after power up. It took me a while to track that one. Well done on that diode, very odd..
Another great video as always. Only ever had one O/C diode fault. It was in an ABB speed drive (VSD) that would fault with D.C UNDERVOLT when only operating at half load. One of the diodes in the 3ph rectifier had failed open. Thanks for taking us along for the journey 👍 Cheers Pete' New Zealand.
Back in the day as a TV repair apprentice I delt with a lot of Germanium doped semiconductors and yes seen similar faults but that's a first for me on a silicon conductor. Nice find. All the best and remember the hot end hurts !!
Mick, why not use the continuity feature of the meter to determine continuity...to determine what the diode is connected to. Shouldnt need to see tracks.
It seems Gunson didn't have a tech that was interested enough to troubleshoot or spend the time diagnosing to find the problem. Replacing a single diode was a cheap fix, so the "too expensive" response was BS. At any rate, this was a great fix and it wasn't a capacitor😉 Your skill at narrowing down the fault to the display board was choice as the rest of the device looked busy. Nice job brother, another win, thanks. See ya soon.
I've seen that. My electronics career started about 40yrs ago. I think bonding faults due to poor manufacturing techniques were solved so very rare oc diodes after.
Brilliant. I bet you were thinking about editing your video with a laser beam addition at the very beginning 😂😂 nicely done too😂. I am also glad this was not a cap but love your vids either way as they always educate me.👍👍
Cheers Darren, I was hoping it was going to come out a bit better, but I didn't have time to spend ages on it as needed to get the video out there. Glad you enjoyed it and found it useful 🙂👍
I have actually used one of those tools during my working life doing car repairs. The green cable is for voltage testing. The control pot is used to check timing advance.
I once had a similar problem with a zener diode in a linear power supply that went intermittently open circuit causing the output voltage to skyrocket. Good that you measured the diodes again because I was also convinced at first that the AD converter/display driver chip was defective. Well done. Thanks for the nice and interesting video. Cheers!
I still use the older version of that gun with fewer options. Excellent units but you have to be careful with the current sense clip which can get broken.
@1:00 - You, of all people, I would have expected to recognize an "old fashioned" timing light. Dad taught me how to use one back in the mid 70's on a Plymouth Duster 318.
@DiodeGoneWild actually had the same problem when fixing a vintage powersupply where the bridge rectifier was located one of the diodes were open circuit while others were fine, he basically listened the buzzing sound of the tranformer to suspect it which was an unusual buzzing
Quite the *Honorable Galactic Warrior.* lol I Knew this was going to be a *Great Trip! BRAVO!* *Thanks* too for continually posting component info, feeds brain cell, stored ready ... _for next life._
Like some that posted. I have also seen diodes fail but this one I think I would add to the one I got a few years ago. It was part of a power supply and a fairly simple one at that. When the diode was test it tested find but when voltage via the power supply was put though it stopped working which made it hard to catch the fault. Also this power supply was 3 phase power supply which was part of a hydro station which power PLC and the charger for the 3 24 batteries. It was a simple diode just 1N4007 from memory and its still running. I know the ones who made (built) the hydro wanted to change all the control gear but the owner didn't. I have done a few things for him in the pass and this is how I got asked to look at it.
I've seen a strange fault where I was brought a guitar distortion box and the thing would intermittently act up. Traced it to to wall adapter randomly dropping out for a few ms! Turned out the diodes went bad in the full bridge and the thing been running half bridge and when the other side of the bridge started to fail, voltage dropped out. The fault was random and almost like noise. Removing diodes (1n4007) and passing even 100mA through them (rated 1A) made them go open circuit. All 4 new diodes and the device it working great
Seen similar oddity. A colleague had an o/c diode (4001 or 2 IIRC) in a full bridge rectifier of a psu, in this case it was breaking down under load so you could hear it shorting across at mains frequency.
The same thing happened to me but it was some smd resistor it reads open when in circuit but reads fine outside the circuit because one end of the resistor wears out and doesn't take solder, intresting to see some through hole diode kinda has the same problem nice fix and i just discover timing light devices
Very cool and futuristic looking ignition timing stroboscope :) Indeed looks like laser gun from the 70's Battlestar Galactica or something :D I remember my dad had basic light blue plastic stroboscope without any displays, which was sometimes used to check ignition timing in cars with old school distributor and high voltage leads to spark plugs. Newer petrol engine cars have coil packs for each cylinder, no distributor or high voltage leads anymore. Engine computer keeps track of the timing by crank- and camshaft sensors, and I guess they can be read using obd scanner.
Seen diode faults like that before, twas my first "one that got away" story from me fixing things. It was fixed and then not and then fixed and then not and then sat for over a year with me unable to figure it out. But then when I picked it back up the diode finally completely failed which lead me to assume it was a slowly failing diode. Seen it a few times since, fairly rare fault as they go but I at one point got a whole series of non descript PSUs on my bench from one batch. They'd all failed in that exact way, assumed a bad diode batch. Replaced all of them, those units never came back to me so I assume they're fine. I both love and hate faults like that, they keep my job interesting. But they can be frustrating as hell especially under time pressure. Diagnosing with a scope tends to find those faults a lot easier in my experience as when you put voltage across it the waveform behaves differently than expected most of the time.
Seeing two diodes one after another suggests that-that is a crude voltage dropper, each diode drops roughly 0.6V so, they are dropping 1.2 ish volts depending on what they are feeding....
Looks like that diode has a break. When you tested it outside of the circuit that one lead was almost straight. It looked like the fault occurs when you bent the lead for insertion into the board.
Yes I think it's a bad connection internally in the diode, and perhaps heat from the soldering iron also made the metal expand slightly and re-made the connection for a while.
Thanks. It's a Sony CX450, handycam. If you check out the video description, I list pretty much all of my equipment, cameras and software etc that I use 👍
I had a similar fault with a Chinese spark plug. New plug, fitted to my mower and it started fine. It ran for about five minutes then died. I restarted the mower after about five minutes and it ran and died again. I thought fuel starvation so spent a few hours taking the fuel system and carb to pieces and found nothing. Put it all back together and got the same start ok, run foe a bit, then die. After scratching my head for a bit I thought the only thing left was the spark plug. I put an old NGK plug from my chainsaw sparesbox and the mower ran fine. New NGK plug ordered and fitted and it's been running fine ever since. I can only think that the insulation in the plug was breaking down when it got hot as a break in the internals would have to be pretty big for the spark not to just bridge any break.
A really good video enjoyed that one. It looks likes something off of Starwars, it was funny when you zapped a chicken as I was saying out loud "Zap a chicken". I think that Diode was possessed as it is halloween.
With me being born in the early 60's , that was a common tool for mechanic shops and home mechanics , in fact that one is way more fancier with the leds and RPM readout .... The ones we had were just a strobe light that would shine on the harmonic balancer .... We would " paint " the timing mark on the balancer and turn the distributor to adjust the retard or advance of the timing ..... In fact it was showing you double of the actual RPM's that it was doing , divide it in half for the correct RPMs ..... On a car engine the rotor would go around to each wire on the distributor to fire that plug .... On a single cylinder like yours the flywheel has the magnet on it and passes by the coil / magneto 2 times , but the cylinder only has compression and fuel in it every other cycle , since it is a 4 cycle engine ...... Your Honda engine or Honda clone would have to have racing parts in it to hold it together at that amount of RPMs .... Ask me how I know LOL...... I was screaming Leaky diode , Leaky diode , but you didn't hear me LOL .... That's where a curve tracer or Octopus attached to your scope would come in very handy , I have one and it's worth its weight .... Great diagnosis and video..
Love you vids and watch it whenever you post I have a interesting fix for you Have a Dyson V15 that turns on and randomly powers down till you restart it again would love to send it and see it on channel don’t know if that’s possible Keep posting love to watch your repairs here from USA
2AM 😂👍 I often fix things in the early hours, it's a lot quieter for recording then having chickens, sheep, and kids making loads of noise. Also the lighting is constant as I haven't got the sun shining in the window onto my bench. Yes interesting fault this one.
I had a thought on the potential shorting between the metal case and display/control board, do you think it would be worthwhile buying some of those rubber jar opening mats to lay between circuit boards? Not sure if that would work or not.
I'm not too sure, I've just had a look as I've not came across them before so thanks for the suggestion👍. I've just used a piece of cardboard or such in the past 🙂
hey there mate shane from Brisbane Australia here just wanted to know what Oscilloscope you are using as i looked in the gear you use and i cant find it there. also thanks for the info on the repair shop here is Australia, it has been great keep up the videos as i love watching them every week shane
Cheers mate 🙃it's a HANTEK DSO5102P. It's not bad, but I might have preferred the RIGOL one as that one can analyse data like RS232 and this one doesn't.
I still dont get what this device is used for. But that with the diode and its bond wire failing was something I thought of when it worked after you pulled it out with the soldering iron.
It's used for setting the ignition timing on old (now classic) cars. You put a white mark on the flywheel and the strobe light flashes when the spark triggers it. The white mark lights up with the strobe, and if the flywheel is in the correct position you know that the timing is correct.
Ooooohhhhh that is cool! I didn't know that yet. That was way before my time. But I am aware of strobe lights giving the illusion of something that's spinning fast to be not spinning at all or backwards depending on if the frequency matches the RPM.
I expect that predates uC by a few years, remember using these or something similar in the late 70's. Did not think Gunton made anything professional. Have a look at the gunson "colour tune" where they expected you to look at the top of a glass spark plug via a crap plastic mirror. 😅
The date on the board is 1994, and I've worked on old video games from the 70's that have Uc's. I've just had a look at the "colour tune" after you mentioned it. That's pretty wild. Someone was tuning a motorcycle on YT with it 👍
@@BuyitFixit i bet that design had been around quite a few years before that as well. the Colour tune, would you look down that thing. i did try one on my mini back in the day, it was never any good. Early uC were more often mask programmed, trying to remember when pic's went from one time programmable (OTP) to uv erasable and then electrical. UV erasable always came with a price hike as you had to have a ceramic body. a quartz window had to be mated to a body with the same expansion coefficient with temperature as the quartz. there is was a point when we went from uP to uC i.e. external memory and peripherals etc to internal. before we started calling them SOC 🙂 makes me feel old now 😞
Yes, the early UC were mask ROMs. I think I might have a ceramic PIC somewhere with the quartz window. I've got tons of EEproms 2704's 08s 16s etc I think I put a couple under the microscope when I was reviewing the Adonstar microscope (video quite a few back now) and compared it with my trinocular, you could see the manufacture and date code on the EEProm DIE, a I think one even had a little picture or logo on it.
@@BuyitFixit once programmed the security bit by accident on a PIC12 with the quartz window only to find the bit was not under or near the window, about a days pay in the bin. And it was my chip 😞i still have it somewhere to remind me never to do it again.
Loving your content, keep it up! Quick question, I was looking into a protective mat for my desk to do some soldering and glueing (3d printed stuff) and your blue mat is readily available everywhere, but saw some info that it is static. What’s your take on this?
Well, people have asked if I wear an antistatic strap etc, and over the years I've never bothered, and I can't recall ever having any problems. I've done around 200 or more videos with the mat, and had all kinds of stuff on it, and can't recall zapping anything (well due to static anyway) 😂😂😂
A strange failure mode for a diode. Like you said they usually fail short. Also nice laser effects at the end, although as marvin the martian said, wheres the earth shattering kaboom :)
Cheers 👍 I did look to add one, but didn't have lots of time to spend on that part of the video. It took me a while to work out how to do it as I was following a tutorial 😂😂
Was the body of the bad diode cracked or damaged in any way? I have seen diodes and resistors go open/high resistance but they are always damaged in some way.
![I.N "HALLUCINATION" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/n5B5q1Hwt_U/mqdefault.jpg)
In 40 years of messing with electronics I have seen quite a few failed diodes but never one like that. Another great bit of work.
Cheers Mike, yes not a common failure mode at all, just goes to show.
Nice special effects with your laser beam Mick! Great fault finding as well.
Thanks Vince 👍Bit of an unusual one that, not came across many diodes that fail that way.
@BuyitFixit Very unusual!!
It's amazing what a few hundred temperature cycles can do to components. I expect it lived in a shed or garage so going warm and cold everyday
@@TheEmbeddedHobbyist Very true 👍
Great fix Mick. It'll be put to good use on my classic MG's and other BL motors from the 50's, 60's and 70's.
Cheers Michael 👍Hopefully it will be back with you soon 🙂
probably a very expensive bit of kit in the day. I just bought a timing light with dial back from amazon for about £35 - although only with an LED for the strobe, but does the job and matches my mates expensive snap on light that i had to keep borrowing.
@@eliotmansfield They're still available new @£420 and on fleebay for £200!
Beautiful fix on a strange fault, but you seem to have found the mystery! As usual I'm impressed! Thank you so much for all those precious informations!
You are so welcome!
That thing brings back memories of a time long since past.
Nice one 👍
In 45 years as an electronics hobbyist, and 40 years as a professional electronics service engineer / electrician, I have NEVER come across this fault with a diode, and I've tested 1000s over the decades in my career.
This is one of those, once in lifetime moments that you rarely see in real time.
The closest I had to this was a high resistance fuse that stopped a UHF transmitter from working when I was in the Royal Navy, it had a resistance of a few Ohms only, and bleeped with a multimeter on continuity bleeper mode, but those few Ohms were enough to cause the fault. We had been going round in circles for ages trying to fault-find that transmitter.
Yes I thought it was quite a rare occurrence. I had an odd fault like this with a Milwaukee vacuum where the fuse was passing voltage but no current (video is on here too).👍
@@BuyitFixit If you can measure a voltage, but you can't draw current, that is a sign that there is a high resistance between the source of the voltage, and where you are measuring. I work on diesel engines in my work, and I have 12 Volt 21 Watt auto lamp wrapped in foam so it doesn't break, connected to a couple of wires, one with an alligator clip to connect to earth / chassis of the machine, and the other wire I made a sharp probe out of a piece of welding rod. If there is a bad connection in the 12 Volt system of the engine, the lamp will not light, or it will be dim. If you measure the same point with a multimeter, it will show 12 Volts or more, giving you the false impression that there is ''power'' there.
There isn't ''power'' there. Only voltage.
It's our old friend Ohms Law that causes this, and the fact that a multimeter, on voltage, is a resistor of about 20 Megohms when connected to the circuit to measure voltage.
A 21 Watt lamp is a resistor less than 2 Ohms when connected to the 12 -14 Volts of an auto electrical system. This is one of the most valuable things to consider when fault-finding 12 or 24 Volt auto electrical systems IMHO.
@@zedcarr6128 Thanks for sharing 👍It's pretty much exactly what I did when diagnosing the Milwaukee vacuum cleaner 🙂
Great video - Thank you. I saw the date and time displayed on the scope. It showed 01:00. I just figured you haven't set the time up. Then later you said it was 02:00 and dark so no chance of trying the test on the log splitter. Kudos to you for not only being a great repairer but also a night 🦉🙂
Cheers, yes it's usually quieter (farm animals) and I don't get sunlight shining on the mat.
@@BuyitFixit bit of 'tweek' ~ *HAIL* _not just Warrior,_ but *mighty Knight.*
Nice to hear Farm Animals from time to time; Hope all's well there. *Cheers!*
I remember small signal transistors BC 108, BC 109 etc go noisy with heat and clear with a shot of freezer way back in 70’s ! Brilliant fault finding video ! Keep them coming! Retired technician, Fraser ,😊
Cheers Fraser! Yes I remember BC108 and 109's 😊
Mr Carlstons Lab has brilliant signal tracer design with non contact probe just for ferreting out noisy components like semiconductors, resisters etc ! Works up to rf and doesn’t load the circuit it’s testing! Details all on his site and you can build it very cheaply ! Cheers Fraser⚡️
Buck Rogers could use that in the 21st Century....😄
Glad to see you were able to fix a substantial piece of equipment like that.
My dad use to have a metal Timing Gun as well. Different design but very well made.
😂😂😂Cheers 👍
More than likely the rheostat is to test total timing advance, you zero it out race the engine than turn it until the timing mark lines up again and it should display the total ignition timing advance.
Yes, I think that's what it's for.
These type of timing lights were quite common back in the day of breaker point ignition systems with an adjustable distributor. After speeding up the engine the knob was rotated till the flashing strobe light came back to the stationary mark. The "total advance" was then read on the digital display, typically no more than 40 degrees if that much. Someone who can troubleshoot/fix down to the component level is as rare as this timing light!
😂😂😂Thanks 👍
I've been messing around with electronics for over 40 years and I've never seen a diode fail like that before!
@@ghwizz interesting, someone else said pretty much the exact same thing 👍
Oh so complicated 😂
I remember back in the day the spark plug wire would go directly to a neon tube!
Yes, I had one of those, although they weren't particularly bright.
No, you certainly couldn't use it in direct sunlight, more probably at night! 😉😆@@BuyitFixit
Nice new channel for me BTW. Thanks Mick.
@@dreamweaver4886 Cheers mate 👍
Perfect timing, would have come in handy when British Leyland products ruled the roads.🤣🤣🤣🤣🤣
😂😂😂😂👍
That was a good fix Mick! I once found an open circuit diode that had a leg that would twist around in it's socket. (Obviously it was only possible to spot once I had de-soldered it.)
Cheers Tim 👍
Had a couple of diodes be Open (usually short is the failure mode like you said)but not caught one like this on the verge/able to recover with heat. Definitely had other components that behaved after heating though.
Yes, had caps do this after heating. I guess the leg expanded with the heat causing it to reconnect with the internals.
Always look forward to buy it fix it videos. Great video as always friend.
Thanks 👍
I've never seen one do that before, probably a testament to cheap parts bought in bulk from the lowest bidder. Having said that I probably would have just replaced it when I observed the open circuit without going any deeper.
Me either. I've had stuff read weird in circuit before, especially if there's charge in a capacitor for instance. Sometimes you get minus ohms etc, so I wasn't sure if it was something else affecting the reading (I've never seen it before on a diode) but when it measured OK out of circuit..
Some where,in my computerized yard,I have the same thing,which I bought 40 + years ago,when cars had points,wow was it that long ago,good video,thanks.
Thanks, and thanks for sharing 👍
I've never seen a diode fail like that. They normally fail short like you mentioned. Good find!
Cheers 👍
I had a faulty diode with the same problem in a car computer module I was repairing the other day. It was an IN4004 diode. The computer had a few capacitors blown after replacing them I still had no 5volt supply to the MCU. Checked the diodes around the MCU and found and open diode. Removed it and it checked good so apparently the heat of the iron expanded it enough to make internal contact. Replaced the diode and the car was up and running. This must be a common problem. Keep some freeze spray in stock it’s great for finding stuff like this.
Thanks for sharing, yes I've got some freeze spray. I used some on the Tascam 4 track digital recorder a few videos back.
I had 10 diodes behave like that in a rolls royce once. The junctions were open when soldered in but ok out. Replaced them to fix the heater system.
Very unusual! Thanks for sharing 👍
That's a new one on me.
I don't think I've found a diode failed open that didn't leave some obvious visual cues. 🎆
Yes, it looked perfect, but the meter said otherwise (well sometimes) 😂😂😂👍
Loved the laser gun fx!
I was watching this thinking WTF? That can't happen! 😲
Well done, that would have completely bemused me.
😂😂😂Cheers 👍
This kind of failures are hard to find. But as always great detective work. Love the videos, great production value.
Thank you very much!
I've never seen a through hole diode do that before. The reason that chip looked like it was already changed is because that was the only component on that side of the pcb, so it would have gone through a flow solder machine to do everything and then after that would be done by hand.
Good idea, yes that could well be the case 👍
I once had a 2n222 transistor that measured fine when cold but went open circuit shortly after power up. It took me a while to track that one. Well done on that diode, very odd..
Cheers. Thanks for sharing 👍
Another great video as always. Only ever had one O/C diode fault. It was in an ABB speed drive (VSD) that would fault with D.C UNDERVOLT when only operating at half load. One of the diodes in the 3ph rectifier had failed open.
Thanks for taking us along for the journey 👍
Cheers
Pete' New Zealand.
Cheers Pete 👍Thanks for sharing.
Back in the day as a TV repair apprentice I delt with a lot of Germanium doped semiconductors and yes seen similar faults but that's a first for me on a silicon conductor. Nice find.
All the best and remember the hot end hurts !!
Cheers Chris 👍
Mick, why not use the continuity feature of the meter to determine continuity...to determine what the diode is connected to. Shouldnt need to see tracks.
Could have, but it wasn't really that important. I was just curious if it was connected to the display or the MCU.
Wow, just wow.
I didn't see any diode failed like that too.
That was really interesting one.
Cheers 👍
It seems Gunson didn't have a tech that was interested enough to troubleshoot or spend the time diagnosing to find the problem. Replacing a single diode was a cheap fix, so the "too expensive" response was BS. At any rate, this was a great fix and it wasn't a capacitor😉 Your skill at narrowing down the fault to the display board was choice as the rest of the device looked busy. Nice job brother, another win, thanks. See ya soon.
Cheers Terry 👍
I've seen that. My electronics career started about 40yrs ago. I think bonding faults due to poor manufacturing techniques were solved so very rare oc diodes after.
Thanks for sharing 👍
Brilliant. I bet you were thinking about editing your video with a laser beam addition at the very beginning 😂😂 nicely done too😂.
I am also glad this was not a cap but love your vids either way as they always educate me.👍👍
Cheers Darren, I was hoping it was going to come out a bit better, but I didn't have time to spend ages on it as needed to get the video out there. Glad you enjoyed it and found it useful 🙂👍
@@BuyitFixit I am also amazed your brain still works past 11:00 in the evening too😂
It's pretty much when my brain comes alive mate, it's 01:56 as I'm replying to you 😂😂
I can hear the flash transformer whining at 7:28, so the flash circuit is working. And diodes do occasionally fail open-circuit. Happened to me twice.
Yes, that's indeed what it is. Yes I think this is the 2nd time for me too, it's pretty rare compared to them going short though 👍
@@BuyitFixit Yeah it is.
An illuminating fix
😂😂Cheers Chris 👍
I have actually used one of those tools during my working life doing car repairs. The green cable is for voltage testing. The control pot is used to check timing advance.
Nice, and Thanks for the info 👍
You are the best, who would've thought. Paul, USA!
Cheers Paul 👍
I once had a similar problem with a zener diode in a linear power supply that went intermittently open circuit causing the output voltage to skyrocket. Good that you measured the diodes again because I was also convinced at first that the AD converter/display driver chip was defective. Well done. Thanks for the nice and interesting video. Cheers!
Cheers Patrick 👍
Brilliant as usual 👍
Surprised you didn't use your PEAKS tester on that diode just to see what it read.
Cheers 👍
I still use the older version of that gun with fewer options. Excellent units but you have to be careful with the current sense clip which can get broken.
Nice 👍
@1:00 - You, of all people, I would have expected to recognize an "old fashioned" timing light. Dad taught me how to use one back in the mid 70's on a Plymouth Duster 318.
Yes, knew it was a timing light, but you have to admit it does look a lot like a laser blaster 😂😂😂
Awesome repair once again, it's a good job you re tested that diode in and out of circuit twice
Thank you very much!
@DiodeGoneWild actually had the same problem when fixing a vintage powersupply where the bridge rectifier was located one of the diodes were open circuit while others were fine, he basically listened the buzzing sound of the tranformer to suspect it which was an unusual buzzing
Interesting. Thanks for sharing 👍
Quite the *Honorable Galactic Warrior.* lol I Knew this was going to be a *Great Trip! BRAVO!*
*Thanks* too for continually posting component info, feeds brain cell, stored ready ... _for next life._
Cheers mate 👍😂
Thank you. I would have tested the two diodes first but would have failed to solve the problem believing both were good
Cheers 👍Yes normally diodes go short, but you should get a reading around 0.5-0.6 for a standard diode, or lower (around 0.1-0.2) for a shottky diode.
I had the same fault on a board. One of the glass encapsulated diodes did the fault you had.
Interesting, Thanks for sharing 👍
Like some that posted. I have also seen diodes fail but this one I think I would add to the one I got a few years ago. It was part of a power supply and a fairly simple one at that. When the diode was test it tested find but when voltage via the power supply was put though it stopped working which made it hard to catch the fault. Also this power supply was 3 phase power supply which was part of a hydro station which power PLC and the charger for the 3 24 batteries. It was a simple diode just 1N4007 from memory and its still running. I know the ones who made (built) the hydro wanted to change all the control gear but the owner didn't. I have done a few things for him in the pass and this is how I got asked to look at it.
@@peewee3ie Interesting, Thanks for sharing 👍
In all my years ! seen failed diodes many times but not like this ! regular Buck Rogers you !!
😂😂Cheers Andymouse 👍
I've seen a strange fault where I was brought a guitar distortion box and the thing would intermittently act up. Traced it to to wall adapter randomly dropping out for a few ms! Turned out the diodes went bad in the full bridge and the thing been running half bridge and when the other side of the bridge started to fail, voltage dropped out. The fault was random and almost like noise. Removing diodes (1n4007) and passing even 100mA through them (rated 1A) made them go open circuit. All 4 new diodes and the device it working great
Interesting. Thanks for sharing and well done on figuring it out 👍
Seen similar oddity. A colleague had an o/c diode (4001 or 2 IIRC) in a full bridge rectifier of a psu, in this case it was breaking down under load so you could hear it shorting across at mains frequency.
Thanks for sharing 👍
Well, this is a first for me, mate. Great troubleshooting👍👍 Now I will have to add to the dam capacitor list, a diode.😊😊
😂😂😂Cheers 👍
Well done, Mick. Hope you have a great weekend. Thanks for sharing with us. (Never seen a Diode like that before)
Thanks, you too!
Time to watch Men In Black again .... love the channel!!
😂😂Thanks 👍
The same thing happened to me but it was some smd resistor it reads open when in circuit but reads fine outside the circuit because one end of the resistor wears out and doesn't take solder, intresting to see some through hole diode kinda has the same problem nice fix and i just discover timing light devices
Thanks for sharing. I think I've had similar with SMD resistors before, but not came across it on a through hole diode either.
Very cool and futuristic looking ignition timing stroboscope :) Indeed looks like laser gun from the 70's Battlestar Galactica or something :D
I remember my dad had basic light blue plastic stroboscope without any displays, which was sometimes used to check ignition timing in cars with old school distributor and high voltage leads to spark plugs. Newer petrol engine cars have coil packs for each cylinder, no distributor or high voltage leads anymore. Engine computer keeps track of the timing by crank- and camshaft sensors, and I guess they can be read using obd scanner.
Yes no needed these days for modern vehicles. I think the owner has some classic cars which don't have any of the modern ECU's and crank sensors 🙂
Seen diode faults like that before, twas my first "one that got away" story from me fixing things. It was fixed and then not and then fixed and then not and then sat for over a year with me unable to figure it out. But then when I picked it back up the diode finally completely failed which lead me to assume it was a slowly failing diode. Seen it a few times since, fairly rare fault as they go but I at one point got a whole series of non descript PSUs on my bench from one batch. They'd all failed in that exact way, assumed a bad diode batch. Replaced all of them, those units never came back to me so I assume they're fine. I both love and hate faults like that, they keep my job interesting. But they can be frustrating as hell especially under time pressure. Diagnosing with a scope tends to find those faults a lot easier in my experience as when you put voltage across it the waveform behaves differently than expected most of the time.
Cheers, thanks for sharing 👍
Mick in his Ming the Merciless mode zapping his viewers…
Flash🚀
😂😂😂👍
Well done, thanks Mick 😁
Cheers Mike 👍
Great fix 👍
Thank you 👍
Brilliant fix Mick loved the chickens pmsl 😂, I haven’t had a diode do that exact problem but had one that was shorted then it was ok when cold
Cheers Gary 👍and thanks for sharing 🙂
@ keep up the good work
Another great repair
Thanks Ron 👍
Another class video well done 👍
Thanks 👍
I had the same problem with an 1N4007 in a SMPS. It droved me crazy...
Interesting. Thanks for sharing 👍
Nice work.
Thank you! Cheers!
Seeing two diodes one after another suggests that-that is a crude voltage dropper, each diode drops roughly 0.6V so, they are dropping 1.2 ish volts depending on what they are feeding....
Yes that's what I think too. Probably feeding the 7 segment displays.
your videos all ways get a thumbs up ... awesome as usual.. love ya brother.
Thank you so much 😀
I've had the same problem!
Thanks for letting me know 👍
Looks like that diode has a break. When you tested it outside of the circuit that one lead was almost straight. It looked like the fault occurs when you bent the lead for insertion into the board.
Yes I think it's a bad connection internally in the diode, and perhaps heat from the soldering iron also made the metal expand slightly and re-made the connection for a while.
You did a great job of troubleshooting.
Thank you 👍
That was a easy fix👍😎
👍🙂
For a great conversation starter, you could put that diode behind glass labeled as:
The Rare, Mythical Freak of Nature That Should Not Exist.
Indeed 👍😂😂
Awesome video, thanks!
Cheers 👍
Great fix, what a fantastic piece of retro electronics too. could I please ask what you use for a lens to zoom down so nicely and in focus?
Thanks. It's a Sony CX450, handycam. If you check out the video description, I list pretty much all of my equipment, cameras and software etc that I use 👍
Never seen a 1N400X series fails open circuit, seen plenty short circuit though (been in the game since the 1980's).
Yes, me too. Unusual one that was 👍
once with a SMD on an iPad about 2 years ago. but never with a through hole LOL
Cheers for sharing Fred 👍
If it’s not a capacitor, it’s a diode 😅. Great troubleshooting as always! -Mat
Cheers Mat 👍
I had a similar fault with a Chinese spark plug. New plug, fitted to my mower and it started fine. It ran for about five minutes then died. I restarted the mower after about five minutes and it ran and died again. I thought fuel starvation so spent a few hours taking the fuel system and carb to pieces and found nothing. Put it all back together and got the same start ok, run foe a bit, then die. After scratching my head for a bit I thought the only thing left was the spark plug. I put an old NGK plug from my chainsaw sparesbox and the mower ran fine. New NGK plug ordered and fitted and it's been running fine ever since. I can only think that the insulation in the plug was breaking down when it got hot as a break in the internals would have to be pretty big for the spark not to just bridge any break.
Well done on figuring it out. Yes we come across some weird faults occasionally which are far from the norm 👍
Goodness i literally just bought 4 of the tp link ower over ethernt devices. I hope mine don't break.
Fingers crossed..
The heat from the soldering iron is effecting the diode. That is why you are getting strange readings.
Yep 👍Said on the video.
A really good video enjoyed that one. It looks likes something off of Starwars, it was funny when you zapped a chicken as I was saying out loud "Zap a chicken". I think that Diode was possessed as it is halloween.
Glad you enjoyed it👍
With me being born in the early 60's , that was a common tool for mechanic shops and home mechanics , in fact that one is way more fancier with the leds and RPM readout .... The ones we had were just a strobe light that would shine on the harmonic balancer .... We would " paint " the timing mark on the balancer and turn the distributor to adjust the retard or advance of the timing ..... In fact it was showing you double of the actual RPM's that it was doing , divide it in half for the correct RPMs ..... On a car engine the rotor would go around to each wire on the distributor to fire that plug .... On a single cylinder like yours the flywheel has the magnet on it and passes by the coil / magneto 2 times , but the cylinder only has compression and fuel in it every other cycle , since it is a 4 cycle engine ...... Your Honda engine or Honda clone would have to have racing parts in it to hold it together at that amount of RPMs .... Ask me how I know LOL...... I was screaming Leaky diode , Leaky diode , but you didn't hear me LOL .... That's where a curve tracer or Octopus attached to your scope would come in very handy , I have one and it's worth its weight .... Great diagnosis and video..
@@cajuncoinhunter Cheers Cajun, yes I thought the RPM looked high I wasn't sure if it was x 10 or something.
yes i have had diodes that go Intermitent faulty
I don't think it happens too often, most faulty diodes I've came across are short circuit.
Love you vids and watch it whenever you post I have a interesting fix for you
Have a Dyson V15 that turns on and randomly powers down till you restart it again would love to send it and see it on channel don’t know if that’s possible
Keep posting love to watch your repairs here from USA
Cheers, shipping stuff from the US to UK is a fortune probably more than the device is worth unfortunately.
Nice find, I think the spooky behavior of the diode has to do something with Halloween ;)
Could be😂😂😂👍
Nice unusual diode failure for a change 😄
Yes indeed 😂😂👍
I used something similar over 40 years ago when I was a Motor Mechanic
Nice 👍
It's Saturday and there's a new Buy It Fix It video!
Cheers 👍
2pm in the morning don’t you sleep another interesting video never believed a diode could do that
2AM 😂👍 I often fix things in the early hours, it's a lot quieter for recording then having chickens, sheep, and kids making loads of noise. Also the lighting is constant as I haven't got the sun shining in the window onto my bench. Yes interesting fault this one.
Interesting diode fault that one. Thanks.
Cheers 👍
I had a thought on the potential shorting between the metal case and display/control board, do you think it would be worthwhile buying some of those rubber jar opening mats to lay between circuit boards? Not sure if that would work or not.
I'm not too sure, I've just had a look as I've not came across them before so thanks for the suggestion👍. I've just used a piece of cardboard or such in the past 🙂
That chip must be a copy of the intersil icl 7107. It could also measure the dwell angle I guess.
Yes I believe it does 👍
hey there mate shane from Brisbane Australia here just wanted to know what Oscilloscope you are using as i looked in the gear you use and i cant find it there. also thanks for the info on the repair shop here is Australia, it has been great keep up the videos as i love watching them every week shane
Cheers mate 🙃it's a HANTEK DSO5102P. It's not bad, but I might have preferred the RIGOL one as that one can analyse data like RS232 and this one doesn't.
@@BuyitFixit thanks buddy
I still dont get what this device is used for. But that with the diode and its bond wire failing was something I thought of when it worked after you pulled it out with the soldering iron.
It's used for setting the ignition timing on old (now classic) cars. You put a white mark on the flywheel and the strobe light flashes when the spark triggers it. The white mark lights up with the strobe, and if the flywheel is in the correct position you know that the timing is correct.
Ooooohhhhh that is cool!
I didn't know that yet. That was way before my time. But I am aware of strobe lights giving the illusion of something that's spinning fast to be not spinning at all or backwards depending on if the frequency matches the RPM.
@EinGamer22 Yes, that is indeed the effect and how it works 👍
I expect that predates uC by a few years, remember using these or something similar in the late 70's. Did not think Gunton made anything professional. Have a look at the gunson "colour tune" where they expected you to look at the top of a glass spark plug via a crap plastic mirror. 😅
The date on the board is 1994, and I've worked on old video games from the 70's that have Uc's. I've just had a look at the "colour tune" after you mentioned it. That's pretty wild. Someone was tuning a motorcycle on YT with it 👍
@@BuyitFixit i bet that design had been around quite a few years before that as well.
the Colour tune, would you look down that thing. i did try one on my mini back in the day, it was never any good.
Early uC were more often mask programmed, trying to remember when pic's went from one time programmable (OTP) to uv erasable and then electrical.
UV erasable always came with a price hike as you had to have a ceramic body. a quartz window had to be mated to a body with the same expansion coefficient with temperature as the quartz.
there is was a point when we went from uP to uC i.e. external memory and peripherals etc to internal. before we started calling them SOC 🙂
makes me feel old now 😞
Yes, the early UC were mask ROMs. I think I might have a ceramic PIC somewhere with the quartz window. I've got tons of EEproms 2704's 08s 16s etc I think I put a couple under the microscope when I was reviewing the Adonstar microscope (video quite a few back now) and compared it with my trinocular, you could see the manufacture and date code on the EEProm DIE, a I think one even had a little picture or logo on it.
@@BuyitFixit once programmed the security bit by accident on a PIC12 with the quartz window only to find the bit was not under or near the window, about a days pay in the bin. And it was my chip 😞i still have it somewhere to remind me never to do it again.
Loving your content, keep it up!
Quick question, I was looking into a protective mat for my desk to do some soldering and glueing (3d printed stuff) and your blue mat is readily available everywhere, but saw some info that it is static. What’s your take on this?
Well, people have asked if I wear an antistatic strap etc, and over the years I've never bothered, and I can't recall ever having any problems. I've done around 200 or more videos with the mat, and had all kinds of stuff on it, and can't recall zapping anything (well due to static anyway) 😂😂😂
@ thx for the quick response, will order one then 👍🏻 (if I blow anything up I’ll just blame you 🙈)
@@roeligan.fishing 😂😂😂👍
Strange fail. Cool fix!
Thank you 👍
When you wanted test the display, you put the red wire in 10 amp, but not the dial on fluke
Doesn't make any difference. I was just using the probes to short the pin to 5v, not measure anything 👍
Whoa, do people still use timing lights! Old school.
Classic cars probably 👍
A strange failure mode for a diode. Like you said they usually fail short. Also nice laser effects at the end, although as marvin the martian said, wheres the earth shattering kaboom :)
Cheers 👍 I did look to add one, but didn't have lots of time to spend on that part of the video. It took me a while to work out how to do it as I was following a tutorial 😂😂
@@BuyitFixit pfft a bag of gunpowder would have done the trick. Dirt flying everywhere.... haha all good. I enjoy watching you fix stuff :)
😂😂Cheers mate 👍
Was the body of the bad diode cracked or damaged in any way? I have seen diodes and resistors go open/high resistance but they are always damaged in some way.
Couldn't see anything at all. Looked perfect 🤷♂️