UPDATE: So I’m running a 3-part LIVE workshop that takes us on… A Time Travel Through Vintage Electronics. We’ll rewind the clock, dive into the tech of the times… (and study the very history of how things were broken and repaired has evolved) The workshop is coming soon, but if you're reading this then you're in luck (or not)... And there's still time for you to sign up using the link below: www.menditmark.com/mend-mark-workshop The workshop dates are mentioned in the link above too.

@MVVblog

24 күн бұрын

I signed up immediately! I didn't understand a word because I don't speak English but I'm sure it will be great!

@haroldbekaroe4556

23 күн бұрын

? M)) p)ft

@davidurk3229

23 күн бұрын

I signed up, can't wait. Greetings from Milan, Italy.

@briangoldberg4439

23 күн бұрын

Is it going to be on youtube, or is this going to be somewhere else like Twitch or something?

@FUNKLABOR_DL1LEP

22 күн бұрын

of course, for me in German 'VE99' and 'curious marc' is nr 1, than 'mr carlsons lab'..

Is there anything that you don't look forward to more than a new Mark video? Keep them coming please!! Also, it would be great to hear how you gained your knowledge. Electronics, chemical, mechanical, you know it all!

@georgedyson9754

25 күн бұрын

Absolutely - go straight there when there is a new one!

@davidroberts3429

25 күн бұрын

Totally agree!

@TheAmazingprd

25 күн бұрын

I'm so happy when a new video is uploaded!

@matthewm3927

25 күн бұрын

I agree!

@wirdy1

25 күн бұрын

I don't know if anyone else notices the superb editing & audio on Mark's videos? Just the little touches like changing the sine audio level as it's varied on the amp, sublime.

Let's get this man some more subscribers. There are a lot of channels that are really crap that have more subscribers than he does. Mark is the real deal when it comes to repairing electronics! This man takes so much time and effort in putting these videos together. In such great detail, next to nothing skills and when something is not available, he makes it himself. Mark is such a nice guy, great knowledge and very entertaining to watch. Every time he puts out a new video like this, you can take your popcorn and drinks and watch this from start to end like you watch a new episode from your favorite series. Keep up the good work Mark, great to hear you move to a new workshop.

@che1602

25 күн бұрын

Totally agree. I’m sure he’s a guy you could have a drink and share a laugh with too.

@andymouse

25 күн бұрын

Yep, I can think of one with double the subs and I don't get it !

@RegiPavan

25 күн бұрын

Spot on! Let's get him more subscribers

@user-mv5bu2kk8b

25 күн бұрын

Like watching a whodone it on telly

@SlartiMarvinbartfast

24 күн бұрын

I couldn't agree more - unfortunately due to the stupidity of the vast majority of the human race most are drawn to the loud, flashy dumb stuff. This of course applies to all walks of life, not only KZread videos.

I recognise that amp as one from Birmingham Repotory theatre. It came into where I was working at hte time for service. The initials JD belonged to John Deakin one of the service technicians. A long time ago in the seventies. He has since passed away sadly.

@PaulaXism

25 күн бұрын

I knew John quite well. He did most of the large heavy audio equipment repairs in the midlands. Nice guy, always helpful. Sorry to hear of his passing.

@bsimpson6204

23 күн бұрын

"A long time ago in the seventies. He has since passed away sadly." But his amp lives on, we should call it 'John's amp' serviced by Mark

Dare I say that Mark's videos are on the edge of being therapeutic to watch! Thanks so much, Mark!

@sobolanul96

23 күн бұрын

He is such a positive guy!

@rokkenbole

22 күн бұрын

Absolutely! I 100% agree!

@bobgrob4

22 күн бұрын

He's in my top 3 list here on YT for sure. He should have a million subs and his channel will grow and grow if he stays with it.

@bobgrob4

9 күн бұрын

it's approaching an addiction for me. I love this guy. Every aspect of his uploads are excellent.

Mark exudes confidence and competence. You know he’ll sort this disaster

Fabricating those transistor covers is just next-level refurb; not only painting, but matching the text. Awesome.

@ZiggyAndTheSpiderFromMars

25 күн бұрын

Mark has the skills and tools for every problem. He even has a labeling machine for this very purpose that cuts out the warning labels per spec.

@OC35

10 күн бұрын

I would have used TO-3 plastic covers!

Mark shows us a level of craftsmanship that many ‘repair shops’ don't even know exists.

No surface mount items, no chips...ah the joy of components that can be examined, tested and replaced without magnification!

@alfsmith4936

22 күн бұрын

Built when amps were designed to be fixed before tomorrows gig.

This is more than just mending. To see someone taking care to recreate missing parts from raw steel is truly a labor of love.

@hubbsllc

23 күн бұрын

And a power amp is ready to re-enter service! Power amps are among the most useful pieces of vintage tech there is. Even a really good one from the '70s or '80s, once properly sorted, is really good even today.

Mark is one of my favorite net personalities. Straightforward with no mucking about. Can't wait to see the new digs.

@bobgrob4

22 күн бұрын

@OldFatBubba many of these techie type people are kinda grouchy. Mark has got the best, most refreshing personality that Ive experienced. His channel should be in the millions of subs. Its money in the bank when he uploads a video. Hes the best by far. One of the main reasons I do KZread.

You won’t find anyone as professional as Mark he’s the best !

The abject anxiety I get watching Mark completely dismantle these old buggers is offset by the dopamine blast I get when it comes back together and actually works.

I bet if you sent Mark a shoebox and told him it was a McIntosh amp, you’d get a McIntosh amp back in 10 business days 😂

@rayofcreation3996

24 күн бұрын

😂😂😂

@alfsmith4936

22 күн бұрын

I'll be sending him my Dumble next week then.. I don't know why it's not working. It's very light too..

@bobgrob4

22 күн бұрын

LOL!!!!

@bobgrob4

9 күн бұрын

I can just hear him say, " some parts were missing so I had to improvise with a bit of wood and metal work here in the workshop." LOL!

The sticky residue on the cables is from the smoke, not dry ice 😁 . The smoke fluid is water and glycol, and the glycol is the thing making the smoke white. If the smoke is used in a nightclub without any ventilation, the glycol will condense on stuff. A typical fault on movingheads is the condensed glycol on the cables inside, making the dust stick on them, and making them brittle.

@BTW...

24 күн бұрын

Imagine what it does to ya lungs.

@app0the

23 күн бұрын

@@BTW... and yet some people are now carrying around pocket sized smoke machines to suck on them at any free moment they have

@jpdemer5

23 күн бұрын

Glycol is in "vape" smoke. Doubt there was much of that in the '70s and '80s. I think the sticky goo is phthalate plasticizer in the clear PVC tubing, which gradually sweats out to the surface (making the tubing itself gradually become more stiff.) That's why it's only the tubing that has sticky crud on it. It's an easy-to-replace item.

@alfsmith4936

22 күн бұрын

If it was gigged, it's probably real smoke.. I replaced the pickups in a Strat I used to use before smoking bans last month and it still stunk of cigarette smoke.

@haakonness

18 күн бұрын

@@BTW... ​ it's also used in inhalers

Can we all admire what appears to be masking tape with “nope!” written on it :D

@marcse7en

25 күн бұрын

"Nope!" ... We can't!

@user-mv5bu2kk8b

25 күн бұрын

I do that at the Cooker before the wife begins

A great end to a hot and sunny weekend. I like the way Mark goes the extra mile to ensure that all repairs leave in a safe condition. Best of luck moving to your new workshop.

A sunday with Mark! Splendid

It's better to watch you working than to watch a Hollywood action movie. Lots of love and regards from Pakistan. Stay blessed.

Genuine shock when Mark said he'll be moving shops, I thought he loved the clutter! Extremely organized, however the lack of space is only somewhat evident(;

i watch his videos only for pleasure..this guy seems very humble and nice...

Not only are you extremely talented in electronics but you also understand how to make things from sheet metal and how to measure correctly. Absolutely awesome and I appreciate your KZread channel one of the best around.

Mark, your attention to detail and general knowledge and professionalism never ceases to amaze. Good luck in your new workplace

Good afternoon Mark! I can relax, cuppa tea, and watch your great video!

Mark, You've even made it to the Netherlands. I find your videos so informative and well-explained. It's just a positive therapy to watch you while doing the work you perform.

This channel is criminally under appreciated, when you reworked that motor a few videos ago that hooked me in.

Your cheerful confidence seems born of experience and a good attitude. Most of us would be scared to tackle the projects you take on in stride.

Meaning to say this for a while. Whoever designed the sound for your videos is a genious. The precision, but also calm inducing.

Cover fabrication at the end was just amazing. Really rooting for this channel to grow big.

Looking forward to seeing the new workshop.👍🇩🇰

Mark, you make these repairs look so easy! The missing parts is simply amateur workmanship and unforgivable.

@drummerhammar

25 күн бұрын

I think when the former repairman found out that the blown transistors were out of production, he didn't bother to look for replacement, like Mark did.

@PaulaXism

25 күн бұрын

@@drummerhammar It was very different 25 years ago. We don't appreciate how easy it is to source parts these days. I had to basically give up on quite a few things back then because parts simply were not available.

@edmaster3147

23 күн бұрын

Mark's a gentleman leaving out displaying his underlaying knowledge and the judgement, though he sometimes subtle hints of what he thinks about other techs' solutions. In this case one cannot know the reason behind not finishing the repair by the previous tech, I know just to well that sometimes projects of gear you don't really use gets pushed behind.

@jpdemer5

23 күн бұрын

Also possible that the amp was cannibalized for parts (those rare transistors in particular).

@alfsmith4936

22 күн бұрын

Back in the day, If it works for tonight's gig, it works until it needs fixing again.

I really like how absolutely every single thing that was done in this repair is left in the final edit. Really gives you a good idea of what's happening that a lot of other channels don't provide

He’s Mend it Mark AND Bend it Mark…!!! those covers are awesome! 👏 🔥

@andrewslade7867

25 күн бұрын

Mend it, Bend it and Print it Mark!

Absolutely amazing repair! You can't admire more that these amps never get old! Thanks Mark

Excited to see the new workshop!🙂

He’s so clever. It seems like there is always something new to learn in each video.

I'll miss the old workshop for sure, Mark. Quaint. Calm. Homey.

I am a hard man to impress but you impress me very much Mark

@user-mv5bu2kk8b

25 күн бұрын

I'm sure that Mark is not that wayl inclined

New workshop coming !!! Interesting Mark. I prefer to keep things as they are. It is difficult enough to keep track of where I put stuff 😄

I know sod all about electronics but I'll happily sit watching Mark carry out his repairs, a true craftsman at work! Love the intro music too! Look forward to seeing the new workshop. Thanks Mark!

This show is the best, he got every tool needed under the sun.

It feels like Christmas! Mark has turned up!

How many of us would take one look inside that thing, and say, "Sorry, no way this can be fixed"? Congratulations on the new shop . . . hope the cat likes it!

I mostly have no idea what you are talking about but your style is very engaging so I keep watching

This is some serious workmanship. Mark you are amazing.

This is my first time coming across your channel, and what a pleasure! Your repairs are so thorough, and your positive attitude is a joy. It's always satisfying to see old equipment being repaired instead of just thrown out. Excellent work.

New workshop?.......looking forward to it!

Thanks Mark. Real entertainment on a sunny Sunday afternoon in North west Germany

Those transistor covers were such a clever idea. The printer trick was clever as well.

That looked like a right basket case, but you sorted it all out very confidently and professionally. Love these videos and the "professional" gag at the start of this one. Would love for you to feature the cat more often!

Sunday is complete… cold beer sitting in the garden with Mark… 🎉😂

I'm kind of sad that you're moving to another shop yours has such honest character

For others watching - you have to be careful when substituting transistors in a power amplifier. It isn't always enough to make sure the replacements have the same or better specs on things like voltage and current - two important criteria Mark did not show here is Ft and Cob. You can have oscillation issues in some amplifier circuits if the outputs arent of similar speed or there is more/less Cob capacitance.

@BTW...

24 күн бұрын

Yes, seemed all too simple a sub. Was there a step missing from the work - to match the amps output gain? After all, the driver and output transistors were substituted.

@markrages

24 күн бұрын

@@BTW... Negative feedback makes the transistor gain characteristic less important -- as it is somewhat close. Gain varies more than that difference from part-to-part.

@jaycee1980

24 күн бұрын

@@BTW... No issue with gain as negative feedback deals with that, but stability can be an issue. I might have considered replacing the transistors in both sides just to make them a matched pair, though i doubt it is really neccesary.

@jaycee1980

24 күн бұрын

what Mark might have done off camera, is tested with a square wave into a load, and looked at the scope. You'd see potential instability as severe over/undershoot on the waveform, with ringing. You'll always get some peaking but as long as it's not excessive and there is little to no ringing, you are OK. The original 2SC1586 transistors had an Ft of 10MHz and Cob of 110pF, where as the MJ15023 has an Ft of 4MHz and Cob of 600pF. Unfortunately there's no fast/low capacitance power transistors made in the TO-3 package any more. I also noted that the working channel had a failed Zobel network resistor. That's usually a sign that the amplifier has been oscillating. Maybe that's what took out the channel that had no parts in it.

I don't get any of the technical stuff but somthing about Marks videos make it compeling viewing. Like many comments on here, I really look forward to the days these come out.

Thorough job Mark as always, you didn't cut any corners...fake parts are a real problem...came across it when trying to source some 2SC2922 and 2SC1905 Sanken devices....The real problem is not finding modern equivalent devices that can deliver the power, but can match the Early Voltage characteristics as well.

Outstanding work Mark, just outstanding. A master of many, many talents. I think I'll miss the current/old workshop, it has such a one man in a shed vibe, a bit of a cosy warm feel to it. However, I can't wait to see the new workshop, you might even have enough space to swing a cat and have a bit of elbow room.

Just loved watching thisv-Takes me back to my Royal Navy Days doing component repairs to communication and Radar Systems. What a beautiful trip down memory lane.

Old school analog amp! Glad to see it brought back to life.

Superb video - it certainly brought back memories of casting envious eyes over Yamaha amps back in the 1970s, which seemed very classy at the time.

Mark, you go after these complete basket cases! Once I saw all those transistors missing, I was yelling TRASH IT! You are amazing!

mark im always amazed the amount of skill you have this shows your a true craftsman :)

I aquired a P2201 in 1986. Legendary. Indestructable. Great sound at home in the HiFi and kicked ass in school gymnasiums, weddings and hockey arenas. That and the P2200 are some of Yamaha's best work.

@diegorhoenisch62

25 күн бұрын

Having worked with that model in the early 1980s, I can't agree with your assessment at all. Yamaha makes some excellent drums, great brass instruments, very good motorcycles, and they make amps. Not great, not good, but adequate. Yamaha's amps have rather a lot of negative feedback which gives them decent harmonic distortion specifications, but they are an unpleasant source of phase distortion. Cheers, Alan Tomlinson

@PileOfEmptyTapes

25 күн бұрын

@@diegorhoenisch62 _Phase distortion?_ What? I mean, with the undegenerated BJT input stage it's not going to be a slew rate king, though relatively high gain ought to help with that, pulling off an amplifier this powerful with an EF2 seems like a bit of a stretch, and the output stage is a tad underbiased as they usually are... but it is a PA amp after all, they're not expected to be the last word in fidelity, and this one still easily qualifies as hi-fi. If you want a model that's beyond reproach by any standard, the ones to look for would be from their mid-80s lineup, like the P2250. Later ones went back to being a bit more on the rustic side, and by the mid-'90s even the noise level had begun to suffer.

I'm American and I love your accent. You are my current favorite KZreadr. Awesome job, I was mesmerized.

One of the best content for any electronics, electromechanical devices troubleshooting, repairs, upgrades and RESTORATION to better than OEM, period

That is the sibling of the P-2200. That was a gorgeous amp with Awesome meters. Its downfall was, Yamaha made custom meter drive amp IC, an IG0.... something or other, that tended to fail and render the meters useless. It had a big Toroid transformer for mains. I never have seen a P-2201, but I can guarantee you that Yamaha would never leave their output transistors open on external heat sinks. This is a case where some lame servicer lost that stuff.

I really admire the methodical way you work, your patience and your perfectionism. Your love of bringing back to life packages that no one else would repair. I don't think there are many like you. Even the videos are well taken. Thanks for what you do.

Happy memories of Servisol Foam Cleaner from my time in the Co-Op TV workshop in the 1990's.... I've still got a tin I "borrowed" before being made redundant in 98.😉 Just shows how little I've been fixing stuff in the last 2 decades. Slowly getting back into it now I'm on the scrap heap. Wonderful video Mark, thanks for sharing. Cheers 🍺

This is a work of art. Been watching for a while and this channel is the best! When MendItMark meets MakeItMark, I feel a sense of serenity. Mark, get that second channel registered.

Your videos are not only educational but also a delight to watch.

Very intriguing! Not only impressed with your electronic skills, your design and fabrication skills also! Thank You Mark!

Thanks for taking the time for this Mark. Hope great things in your new shop!

Woot woot!!! New repair video. Can't wait to see what you have in store for us at your new location!! Congratulations, Mark. Thank you for sharing your knowledge with us.

what an absolute delight watching you work Mark. your expertise is amazing and going all the way of doing the covers and labels wow..thanks for your great content and time to put it all together

Thank you for the new video. It's always very entertaining watching you repair equipment! Cheers.

Hope your new workshop is everything you want it to be. Your skills as a teacher and a tech are first-rate.

Very impressive work Mark! Thank you for making these videos, looking forward to your new workshop.

always a pleasure to watch this electronics wizard at work...very nicely done Mark..well done.

Very encouraging video. I have a 1970s Sansui Ba-f1 power amp I have been struggling with for weeks after recapping it and causing shed loads of issues. But compared to this thing it looks brand new. I won't give up.

poetry in motion watching you resolve the problems congrats for the new workshop .

yo sueño con tener un taller asi, y por supuesto, tu nivel de conocimiento para hacer tus trabajos... es impresionante, no conozco a nadie en Chile que llegue a ese nivel. Saludos Maestro!

wow, brilliant work. Also thank you for showing all the searching for components.

Beautiful job! Thanks for the video. Looking forward to the new shop!

Excellent work Mark. Love your attention to detail 👍👍

Thank you Mark for letting us once more enjoy watching great workmanship.

Never fails to disappoint. Always worth the wait. Looking forward to seeing the new workshop Mark, thanks for the effort you put into these videos!

Very impressive work you do not everyone can do...fantastic building of the Transistor shields...cool.. nice Equipment you have either...and a great knowledge in Electronics...

Hi Mark. I enjoy your troubleshooting but I cant get enough of your manufacturing your parts. Love it

I have been following you for a while now Mark. It's great to see a teck take pride in his work . Well done !!. I love these Yamaha amplifiers, built to last. I have a Yamaha P3500 in my lounge room, followed by a Yamaha graphic equilizer Q2031 and a Nad tuner preamplifier 917. Old school , yes but still sounds good and plenty of head room !!!. Keep up the good work and looking forward to your next post and in your new workshop.

i keep catching myself holding my breath when I see the solder fumes hahaha

Such rewarding fun to watch your videos. Looking forward to seeing your new workshop soon!

Good repair and safety enhancement of a great old amp. Look forward to seeing the new workshop.

Once again you have gone over and above on this rebuild. That amp will last for many more hours now. Very nicely done.

What a thrill to watch your vids. Someone also called Mark who still uses an analog 'scope and has a copy of Towers. Though I'm now retired (semi) I love watching someone else work; especially with the talk that accompanies it.

oooh new workshop!! Can't wait to see it Mark! Great job on the amp, great video as usual

I am really happy for you. Well equipped, well knowledged. And I am gone miss your work bench. Work safe my friend.

Congrats with the new workshop, looking forward to c it, great job as always.

Thanks for the hearing test @46:30 ! Nice work. Congratulations on the new workshop!

Congrats on the new workshop.. looking forward to seeing it .

Love watching your videos. Even though i know nothing about electronics or amps, it's still a joy to watch you fix old equipment. Goo luck moving to your new workshop.

Looking forward to the new shop. Well done as always.