Switch Mode Power Supply Troubleshooting And Repair - Yaesu FT-1000MP

See the entire troubleshooting and repair procedure for a switching power supply. This supply has multiple failure points due to "Another Tech." Let's find all the bad parts, and bring this Yaesu FT-1000MP back to life!
To learn electronics in a very different and effective way, and gain access to Mr Carlson's personal designs and inventions, visit the Mr Carlson's Lab Patreon page here: / mrcarlsonslab
#restoration #electronics #repair

[@MrCarlsonsLab]

To learn electronics in a very different and effective way, and gain access to Mr Carlson's personal designs and inventions, visit the Mr Carlson's Lab Patreon page here: www.patreon.com/MrCarlsonsLab

[@mikesamra9126]

I can't count the number of times in the 80s and 90s when I worked on Japanese-made products when the glue on the board to hold down components would become conductive and just give me fits. It was very common in VCRs and TVs.

[@Daveyk021]

Problem with most switch mode supplies is that schematics for them are not available. If you would have found the switching transformer had an open primary, that would probably have been that?

[@edpickering8075]

Thank you so much...

[@XPFTP]

Futaba does RC stuff dont they ??? controlers and servos . had few of there servos in rc cars and helis

[@orion310591RS]

Could we solve this by using component tester to show high leakeage? If we dont have curve tracer, can we use simple component tester and pay attention to leakeage current? Its Reverse Current, Ir? Or I am wrong?

[@julesl6910]

The remarkable thing about this channel is how he spends hours reworking specific little parts of a device, while keeping the whole device in mind. What I mean is you never once see him re-connect the power supply and ZAP SPARK CUSSING ohhhh man I forgot to plug that part in. He gets everything working methodically.

[@KHarp1984]

Man the FT1000 repair and modification video from 8 years ago was what introduced me to the channel... what a treat to see another one... good times.

[@stephensams709]

It was the first video that I watched as well and then I was hooked : )

[@TightLoli]

Same here. I'm an industrial electrician now. Thanks, Mr. Carlson. You'd be surprised how much these videos you make have given me joy. There was a time when i had none, and now I have a family and career i love. I'll watch every video you ever put out.

[@johnackley3982]

Same and this radio reminds of that.

[@user-lp3cf5yn5b]

Lol, I don't know about it being a treat, more like scary, cause I have one of these rigs. I need to make sure and put Mr.Carlsons vids in a playlist in case mine dies

[@JCWise-sf9ww]

Liked how you methodically troubleshoot the switching power supply, finding a leaky zener diode with a curve tracer proved it was bad where the conventional diode check on the meter did not see that issue. Definitely took the mystery out what's needed to make the switching power supply work. Great job!

[@leocurious9919]

What I would have liked is to see another method to find this issue, since a multi-meter was unable to do it, but hardly anyone is going to have a curve tracer.

[@JCWise-sf9ww]

Loecurious,@@leocurious9919, An alternative would be to use a variable DC power supply and connect zener diode and your multimeter in series with the variable voltage source and look for leakage as you increase voltage. If you see a gradual increase in voltage before getting to the zener regulating voltage. You would then know the diode is leaky. Hope I explained it good enough for you.

[@willjackson1955]

@@leocurious9919 Realistically, a simple curve tracer can be built by anyone with an oscilloscope, old or new, plus a small transformer, one resistor and a set of probes. Mr Carlson's tracer is just a slightly more advanced take on the old "Octopus"-type tracer You sweep the x axis with a sine voltage, current limited (usually you do 1.5 to 5V to avoid damage to TTL circuits, and limit the current to maybe 1mA max due to a direct short) by a 1k resistor and read off the current with the resistor. A scope in XY mode provides the display, and since the resistor is 1k you read off mA directly on the scope, and volts across the X axis. Simple as that, less than ten components and you have pretty much the same curve tracer. Just search for "Octopus curve tracer" and check the images, you'll have a visual description of what I've just said. Diodes act the same way as on Carlson's video, resistors, capacitors and inductor all have their own "signature" curve. Combinations of them, too, are visibile and very informative!

[@Sloxx701]

I've been following your channel for 7-8 years and I built your curve tracer some time ago in a stand alone box and use it with a Tek 475. A while back I also bought a Fluke 6071A RF sig gen that was completely non-functional for cheap that had a myriad of issues (and holy cow is it heavy and hard to work on!), and I slowly brought it back to life. It had a completely unstable output carrier frequency that would wander all over the place and I eventually traced it back to a leaky TL084 op amp in the hetrodyne oscillator board that I found using your curve tracer. I knew almost nothing when I started in electronics in 2015, so thank you Paul to your channel and patreon and the knowledge you bring.

[@MrCarlsonsLab]

Thank You for your kind comment, and feedback.

[@gregmesemondo1401]

All men have dreams. Some of us dreaming of having a workshop and knowledge of Mr. Carlson. I need a poster in my house. Not sure what my wife will say though…

[@davidp7163]

Listening under headphones. You did a good job not picking up the outside noise, I wasn't hearing anything but you. Great Video, thanks for sharing.

[@MrCarlsonsLab]

Glad you enjoyed David!

[@iranausley8150]

Nice work! Switchers are tough to troubleshoot. You made it look easy, but it is the experience that does it.

[@8BitNaptime]

HO yes, feedback loop, big voltages, lots of power... I'm not an expert so what I usually do is find the loop, open it, and start from there by seeing what it does section by section with a dummy load. Of course, if the first thing it does is explode, you know you had RIFA caps somewhere...

[@coll6]

My experience told me I would have never figured that out. I have no tool that would have let me diagnose a zener diode failure like that of even to check it past the multimeter. I probably would have just slapped a resistor in there and left it at that.

[@spvillano]

@@coll6 either substitution or a series resistor and power supply to see what it breaks over at would easily tell you. I usually went with substitution, as I kept a shelf full of parts in stock for repairs.

[@mackfisher4487]

Mr. Carlson, it's nice that you repaired a fellow amateurs equipment. 73 P.S. Hope you and yours are safe from the fires.

[@rebokfleetfoot]

studied for a few years, did the job for a few years, but this video made some things clear which i never quite got

[@richieleon]

Great Job Mr. Carlson, Oh the suspense of the last few seconds before you fired it up! Thank You!.......

[@chrisshorman522]

Built the curve tracer. Ton of fun and a great learning experience. It's a great comparative tool. Fixed more than a few things quick with it. Paul's a genius.

[@mastershifu23]

Howdy! That is real interesting, I must admit. Could you please help a fellow and share the link to one you've made? Thank you.

[@spvillano]

That used to be a beginners project, with a complete discussion of theory of operation, back in the day. If there's one thing I've never declined, it wasn't another drink, it was offered free training. :)

[@Dkentflyer]

My late father had a FT2000 it was an amazing piece of kit, he would of loved your channel. When I see you repair radios like this it brings back many happy memories of me listening to the radio with him in his shack. Thank you so much for sharing.

[@MrCarlsonsLab]

You're very welcome!

[@tomschupbach2200]

I dislike getting someone else's kludge job into my shop for repair! You did a great job straightening it out!

[@mkepler5861]

hey Paul, while about an hour and a half of time, it was well worth my time. I had heard of a curve tracer, but never have I seen it put to work to solve a problem. what an incredible piece of equipment. and you built it yourself, sounds like I need to get on your patreon channel. thanks mike

[@WECB640]

The troubleshooting skills here are exemplary! Really outstanding work Paul. I enjoyed watching and I picked up several pointers. Thanks & 73.

[@lesterm23]

Thank you, I'm a patron member of yours.

[@Synthematix]

Wow the power supply is made by futaba, the same people that make rc cars?

[@MrCarlsonsLab]

They also make CNC power supplies for industrial application as well.

[@dennisf4194]

Incredible! I was just handling the same supply for my FT-990 that I extracted over a year ago after replacing a couple of caps and left it in despair due to its complexity and my boot camp level trouble shooting skills! I took a peek at at a few days ago and gave up again. You've given me fresh wind in my sails to give it a sporting try! Thank you so much Mr. Carlson, you are an emissary of God! Dennis - W4ZOR

[@mikesage9544]

Good on you Dennis. Go for that repair. I adore my 990s. Dont hear them so much now. But when you you do.......... The reports I have had. 73 de Mike.

[@pierremartel3552]

I already had a good idea on how switching PS worked but you just finalised my knowledge to a level that I am now pretty sure on how to debug them!! thanks!! proud to be a patreon user!

[@charlyreyesolivares197]

THANK YOU VERY MUCH SIR CARLSON IT'S A PLEASURE TO WATCH YOUR VIDEOS YOU TEACH US A LOT AND YOU EXPLAIN IT SO WELL THAT IT EVEN MAKES YOU WANT TO REPAIR AN APPLIANCE LIKE YOU DO THANKS AND GREETINGS TO ALL YOUR FOLLOWERS 🎉🎉😊

[@MrCarlsonsLab]

You are very welcome!

[@DJRatAttack]

As someone who has been electrocuted before I can say it's a shocking experience and I would love people to take percussionaries when working with electronics especially with high voltage because it does not feel good once you have such a shocking experience

[@NoInfoFound]

Clearly you and the subscribers are fans of tube based equipment, but I watch the solid state based vids. Thanks for posting this!

[@MrCarlsonsLab]

You bet!

[@garyspencer1711]

Ex-sue-lent troubleshooting methods. You never shy away from big challenges to resuscitate NICE radios. Thanks again Paul !

[@justicelut]

That zener diode leakage was one trap for young players! Well done Paul, thanks!

[@SirMo]

I have a curve tracer oscilloscope kit, which I rarely use. This video reminded me to use it more often. I certainly would have probably thought that Zener was fine.

[@Sloxx701]

Great work Paul! Love to see you work on more modern gear, especially ham radios.

[@LakeNipissing]

1:26:20 . . . Maybe there is a chance to get a 'broken' FT-1000 for a bargain price because the backlight wires were not bundled away from the ribbon cable.

[@Greg-et2dp]

Mrister Carlsons lab you are good at restoring vintage shortwave receivers and alignment of vintage shortwave receivers my friend 😅😅😅

[@ariedekker7350]

Thank you Paul. I was once again allowed to travel along in a fascinating story. 73 pe1krx

[@tonyking9235]

AMATEUR WORKING ON IT WOULD BE CORRECT MR CARLSON. IM AN AMATEUR AND I WOULD NOT DREAM OF PLAYING AROUND WITH SUCH A SOPHISTICATED RADIO. NICE ONE AS AWAYS

[@LakeNipissing]

Not owning one of these, it is a big surprise to see an SMPS in a receiver (transceiver) intended for operation in LW/MW/SW bands, since they are known to wipe out reception in these frequencies. Would have expected a 'quiet' conventional linear power supply.

[@jagmarc]

SMPS can be designed as quiet as you want it to be, it doesn't have to be noisy. They're only ever noisy if they don't need to be quiet!

[@BillyLapTop]

My Icom IC 736 has a built in switching supply. I bought it new in 1995 and it is still A-OK to this day. No noise, quiet as a mouse RF wise.

[@LakeNipissing]

@@jagmarc True. And Yaesu employed a significant amount of shielding; in SMPS the transformer itself ends up being a 100 kHz or 200 kHz 'LF antenna'. I have a few LED ceiling lamps and 5 VDC USB power supplies which can wipe out the entire LW and MW band on every radio in the house with exception of a few 50 kW 'local' AM stations, and even they suffer noise. It is amazing Yaesu was able to shield the SMPS so well it can be located right _inside_ the radio with no trouble.

[@jagmarc]

This particular SMPS is a *Forward* Converter, inherently quieter from the start. Plus it includes some neat architectural features to make it quieter (someone else can mention them). It's the *Flyback* Converter type SMPS which gives all the bad name to switchmode supplies and it's because they're so cheap to make, mainly a flyback transformer is trying to do two jobs in one. Instead of it having an outboard inductor to store energy (i.e. L3 on this psu), with a Flyback C. the energy to 'flied-back' is packed inside a teeny weeny little gap put in the magnetic flux path, a gap in the core. Then with a sharp bang the energy flies over to the secondary, and zapps through leakage inductance, like a genie escaping a bottle, no wonder it's so noisy. These Forward Converters are a completely different animal. They don't store energy in a gap in the magnetic core, in fact it's the opposite there needs to be an active clamp to *reset the core* every cycle, if not it'll 'pump-up' and then saturate, ... bang.

[@ke4est]

LOVE IT, when you do Ham Radio repair!!

[@hughmc5419]

I remember in school seeing an instructor do a demo on Zeener diodes, they call it the knee voltage at breakdown/ rated voltage. It gave a more intricate picture. Enjoying your video. We just pulled a ABB 520 amp 600 DC volt DC contactor out of a CNC machine. It puked. Well back to work, now in Valparaiso, Indiana. Hugh Mc.

[@chrisosborn1693]

Another excellent , informative video. Mr Carlson's self confidence is even more impressive than his skill. Nothing ever seems to baffle him.

[@UKDrew]

Awesome as Always.. Wow what a mess Pleasure to watch and learn..

[@AlejandroLopez-qd3xm]

That was just the type of troubleshooting I ve been waiting for! Excelente example of why I need to get myself a curve tracer! Thank you!

[@wyattarich]

You're a wizard of the modern age! Thank you for another fantastic video!

[@kristyskirt9015]

This one by Professor Paul Carlson a tough one. This shows Paul’s ability of electronic troubleshooting with Correct disassembly and correct alignment in assembly with QC checks per step. Big dollar troubleshooting and repair of a high dollar Ham Transceiver. Lot of information on using soldering iron and test equipment. Thank you Paul.

[@gn1656]

Wow ! Someone is very fortunate to have you for a friend that could repair this great rig.

[@elson2k]

Great stuff. I think I learned about electronics in practice in a few of your videos more than I have in school in 4 years.

[@davidberndt6275]

Its been a while since the last smp repair!

[@atw4321]

Thankyou Paul i learned alot for trouble shooting switch mode power supplys as i have a few in equipment i own...no problems yet but as you know its only a matter of time thanks again ...termiteaudio

[@Tony770jr]

Nice troubleshooting! Especially with the leaky zener.

[@marcusbadoyo3112]

At 1:04:00 the 21 volt measured is not the startup voltage but the regulated voltage from the backfeed because the power supply was working at that point. You could have traced the startup voltage during power on time on a oscilloscope.

[@martinsiebert1368]

I volunteer as a repairman at the Repair Café: Quite common is the failure of switching power supplies in devices that our customers bring in for repair. In switching power supplies, troubleshooting is often difficult because the overall function results from the interaction of many components. If one component is faulty, the whole thing will not work. Isolating the fault is often difficult when everything depends on each other. Thank you for pointing out that diodes and Zener diodes can also have leakage currents like capacitors. I did not know yet. Also important is your hint in this video how important the correct position of switching wires in the devices are for avoiding unwanted electromagnetic interference.

[@Sentinel-1]

It was a real pleasure to watch such professional work with such excellent test equipment in expert hands. Great job finding the root of the problem! 👍🏻 It has been proven again that there are no poltergeists and curses in electronics, only bad components. 😁 Just a side note: instead of the curve tracer, if someone doesn't have one, you can use a laboratory power supply with current limiting and built-in ammeter, gradually increasing the voltage. If the resolution of the built-in ammeter is not enough, then you can connect the multimeter in the microammeter mode in series with the component under test. This is not so visual as the curve tracer, but it is also quite effective for finding leaking components.

[@jasonbryant2377]

I know this took forever with videoing and all. But it was REALLY helpful to see this process. THANK YOU!!!

[@pomme4682]

Mr Carlson, you are a genius! As one who used to repair electronic equipment, and also teach the subject at college, I can only admire your patience and ability to follow a logical course in tracking down faults. I was always very wary in attempting to repair switching mode PSUs especially as here in the UK the mains voltage is 230V so you might end up following a trail of damaged components! I loved your curve tracer with its ability to display the characteristics of components where a multi meter might not reveal a fault such as leakage. Just one small point. It would be useful to have a brief introduction to the principles of operation such as why SWPSUs have a high frequency oscillator which switches on and off a power output stage. Otherwise a superb lesson in fault-finding techniques.

[@W1RMD]

Thanks for doing a switch mode power supply and ham radio repair. I like these longer videos as well as your short ones. Take care.

[@remaca]

Thank you very much for sharing this experience! I enjoyed every minute of it and learned a lot! I’m currently trying to repair a faulty HP 8591E Spectrum Analyzer. Your in-depth analysis provided a lot of insight on the methodology and techniques useful in repair of any complex circuit!

[@fredflickinger643]

This is a testament to knowing what the capabilities of your test equipment. It's too easy to forget the limitations of what is perceived as a simple diode check! Great perspective on troubleshooting as well as awareness of your gear.

[@Greg-et2dp]

Mrister Carlsons lab your utube videos are awesome my friend 😅😅😅

[@organiccold]

Well done Paul. This one was a hard one! Someone had released all the Magic Smoke that thing had in stock and more haha. Nice FT-1000. Only other high quality videos about repairing these transceivers that i can remember are made by the Brazilian Electronic Engineer Ivo Muniz in his KZbin channel with the same name. 73 73

[@airmann90]

Oh helll yes. Multiple failure and loooonnng video. The best!

[@xray111xxx]

Wow following another person is always dicey if their troubleshooting skills are suspect. Great work Paul. I am always impressed with your work. You are the science teacher I wish I would have had. My electronics career would have skyrocketed.

[@tomharris1457]

Been working on gear for years, yet learn soooo much from each of your videos. Please return to the boatanchor shoot out. Tom

[@Slugg-O]

Paul, have you considered renaming your channel to The Joy of Electronics with Mr. Carlson? I ask because you are most certainly the Bob Ross of electronics. Your ability to speak calmly while methodically explaining each troubleshooting and repair step in great detail is inspiring. Thank you for another great video.

[@richardross3815]

Now that sounds logical…. Lol

[@AlejandroLopez-qd3xm]

I find his voice so shooting and relaxing that is actually therapeutical for me. My down trobleshootings are a lot more frustrating, usually!

[@jorge195501]

Thank you for a good video, way back at one time you say, I will make you a good electronic technician. I believe I am now, appreciate it very much, for these never ending journey, I wish the best in all you do , Mr. Carlson’s.

[@rickn501s]

You are incredibly patient and competent. Thank you for taking me through your troubleshooting procedure.

[@JesusIsLordofMybeing]

Another masterpiece video Mr. C. You really make everything look too easy but thanks for this amazing venture.

[@Greg-et2dp]

Mrister Carlsons lab the owner yaesu ft 1000 pm transceiver is awesome my friend 😅😅

[@rickoneill4343]

Great job at filtering out those vehicles. Didn't hear a single one!

[@greengrayradio1394]

Very good description on the fault finding and repair of this strange fault! The leaking zener, which required curve tracing to reveal, is interesting! Also, good tip to reverse feed the o/p to confirm FB circuits are ok. I have repaired and struggled with many switching power supplies and know they are "beasts" when they don't work, so this is very good info, Paul!

[@sylvainbel]

WoW quel beau travail de patience et de minutie 👍

[@MrRoundel]

Wow, another awesome video, Mr. Carlson. Despite my rather meager knowledge of electronics, I love watching these videos. Years ago I worked in a VCR repair shop, so I have some knowledge, but again, it's minimal, as I worked mostly at the front. I know a good, OK great, troubleshooter when I see one. I don't think a lot of techs could have figured that out, nor would they have the great equipment to test. Your skills and knowledge are astounding. That curve meter (?) to check the diode leakage was amazing. Thanks for the trip through the circuitry, etc. Most excellent content. Cheers.

[@AK-vx4dy]

Wow...i was sure you take only devices with at least one tube.... strange..... But as always fascinanting story with warm "tube vibe" voice... and i'm lost for 90 minutes....

[@robertcalkjr.8325]

Very nice troubleshooting and repair! Thanks, Paul.

[@faxcapper]

Great detective work, Paul.....this video was a solid 12 out of 10. :-)

[@MrCarlsonsLab]

Thank you kindly!

[@scowell]

Very good! Switchers are a black art... nice to see one repaired. Many ham radios just expect 13VDC, the power supply is external... so now I'm more determined to never buy a unit with an internal one! Been using Yaesu since 1991... good stuff.

[@bigjobs7781]

Brought to you by "Blammo Electronics..!" LOL.. Love the tong ESR meter BTW.. very handy.

[@fichambawelby2632]

Anotherbexcellent job done, Paul. Congrats! 👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏

[@Oldgamingfart]

Reminds me of those old Panasonic VCR SMPS' with the 1uf 'bootstrap' capacitor that would dry-up, so the oscillator wouldn't get that initial kick ..usually right after a power cut! Lots of similar Zener and irksome output regulator issues in those, as well. Hours of fun! :)

[@geoffreykeane4072]

Great work Paul, I’ve seen most of your videos and I have to say I enjoyed this one very very much.

[@MrCarlsonsLab]

Many thanks!

[@OldSkoolF]

Absolutely my favorite type of videos... Thank you!

[@jwl9286]

Thanks. I'm stunned at everyone of your videos. I'll admit, I have a long way to go before I'd ever touch that power supply. I have to chuckle that your leads and temporary connections hinder you the same as me. We emphasize ohms law but to add Murphy's law and you are so right.

[@richroggio]

this was a great video Mr. Carlson. I used to own a Yaesu FT 101- EE back in my Ham SSB radio days.

[@jamesvw769]

Thanks Carlson. 👍

[@MrCarlsonsLab]

No problem 👍

[@NoInfoFound]

Hey, it is Mr. Carlson :)

[@jcramond73]

A big G'day from Australia Paul and once again, thanks for another great rebuild.

[@MrCarlsonsLab]

My pleasure

[@miroslavstevic2036]

Great troubleshooting, tricky problem. Well explained. Most of beginners wouldn't be able to figure out leaky diode. I think you immediately knew where is the problem (from experience), but the video is prolonged for educational purpose.

[@finnthehuman5260]

I wish I could hang out with Mr. Carlson

[@nelsonjoaquim5918]

Hey Paul. Great investigation video ... searching for the guilty component, the one in hiding....loved it. What's next I wonder?? Cheers

[@heinerrambold8889]

this radio has a dc socket at the back. I had removed the switching supply, saved the money for repair and would feed it with a big lifepo battery. Thanks for the video!

[@Ronl53]

Thank you for this video. I learned a lot. I also want to thank you for the effort you put in to the camera position and the audio.

[@MrCarlsonsLab]

You're very welcome!

[@c185pilot3]

Simply brilliant...I never cease to be amazed by your knowledge and talent...thanks for your efforts

[@johnburns6422]

This guy is so far up the electronics ladder his knowledge is way ahead of any one , with NO Dis respect to the other people

[@rankenfile]

Well done! That was a sneaky leaky diode.

[@winstonsmith478]

What a beautiful example of electronics hardware.

[@EnchantedForest-]

excellent video. watching from Sydney Australia.

[@patrickm3882]

Great video as always, Paul! I would love to know why the trick to test the Darlington transistor works (the initial dim light), and how you know to test for ESR vs leakage? Maybe a couple short videos on those tricks of the trade?

Troubleshooting SMPS is a funny activity! If it's from a Ham radio like this you show, it is a lot of fun and learning activity! Thanks for sharing. Congratulations by your channel. Thank you !

[@mohamnazeerhm2019]

wow what a great video, your methodical way of working your way through the problems is amazing, more of this please. Every man must have a curve tracer👌🤟

[@billelovski2783]

Amazing video, you are an amazing teacher. Very easy to follow

[@MrCarlsonsLab]

I appreciate that!

[@r7boatguy]

Today I learned about leaky diodes! I continue to be amazed at your knowledge and experience.

[@terrym1065]

What a lesson...What a lesson, I learned so much Mr C, thanks so much for this incredible video. A little late to the party, had an accident that broke multiple ribs in different locations on the very day this video aired so getting to watch now. Your level of skill is really extraordinary and the quality of your videos is second to none, I'm grateful to be able to view them. Complex fix on this power supply and it came out of a complex, expensive radio, good job. Excellent video and results, thanks again for the work. 73 KC5NEX

[@kevincozens6837]

Good job finding a leaky diode. No wonder the previous person that worked on the power supply didn't get anywhere with it. Not everyone has a curve tracer or might have thought to use it to check the diodes.

[@techobaz55]

A great video Paul, your explanation of switch mode diagnostics is next level. Thank You !

[@MrCarlsonsLab]

Glad it was helpful!

[@RGB06084]

Great work Paul! 73

[@francisMbizaree]

An avid long time hobbiest follower and listener from the Philippines🇵🇭😊😊😊 I just want to thank you Sir for sharing your knowledge and giving some insites lectures and tips for free about the intricate wisdom in the world of electronics. I really enjoyed watching your videos about restorations and repairs you've had made. Again, thanks a lot Sir😊 mabuhay🎉

[@MrCarlsonsLab]

My pleasure!

[@Greg-et2dp]

Mrister Carlsons lab my hobbies are painting pictures and listening to shortwave and ssb iam thinking about getting my ham license 😅😅

[@silvanomoreno6950]

Great job, many thanks for sharing your experience.

[@MrCarlsonsLab]

My pleasure!

[@Edisson.]

Thanks for the video, a wonderful demonstration of diagnostics and a beautiful proof that the diode tester can't find everything. I can't imagine my workplace without a curve tracker, I have been confirmed several times with similar partial damage to the diodes. The last such damage happened due to the degradation of the glue used to fix the parts. Nice day 🙂 Tom