Hello Mark! Silver plating the power switch contacts, after perfectly recreating dome shaped surfaces on both contacts... I have not seen anyone on TH-cam ever go through that much fine, precision work to restore a vintage power switch! You are clearly in a league of your own. Beautiful attention paid to every detail, to the point that you even consider the next repair person, when reattaching component leads speaks volumes to your ethic as well. I love your work. I am so happy that I found your channel. Please keep it up as this is really great stuff! Thank you for showing all of us how it should be done proper! Fred
There's a lot of great content being created like this channel i have a few other repair channels i like to watch while i'm waiting for new content to be released. I probably waste to much time watching all these channels lol.
Normally Im not at all interested elecronics but Mark make it fascinating viewing. At 26:40 "I`ll just bend these legs a little bit, not to much, out of respect for people who might service this in the future." I doubt if there`s anyone out there who could even attempt this level of work. Simply amazing.
ปีที่แล้ว +17
You are an Artist in electronics, mechanics, physics and chemistry. I am a a very old engineer and professor that armed valvular and transistor equipments in the 50´s to the 80´s. I admire you , and give me Hope in young people like you. Cheers from Patagonia, Argentina.
Very minor quibble, as the contacts will slowly deteriorate over time from the effects of the electricity when contacts mate and break. It's nowhere near a sealed relay. Future repairmen will probably be more curious about the lighting regulator! Jolly good show 👍
I love the engineering that went into making these old units. (I say 'old' reluctantly because I remember when these were the latest thing!) Made to last, and made to be repaired - something so sadly lacking in so much of today's tech. Just love the extra mile Mark always goes when restoring or repairing them. One of the very best techs on TH-cam for this kind of stuff.
They cost about a month's wages when they were new, they were very expensive. I'd guess the cost of that service and repair work would far exceed it's actual value. But it's possibly someones pride and joy.
Mark, that re silvering of the contacts was a brilliant move! That is what I like about your channel. Inventive! Love it! Keep up the good work and your channel will grow, you are up there with the best!
This is probably their best analog receiver lineup overall due to appearance, performance, and ease of service. All have discrete outputs save for the oddball SX-650 which uses SanKen SP-40W modules. I just did an extremely comprehensive service and upgrade on an SX-650 including a full recap, new schottky rectifiers, retrofit OPA1611 opamps and discrete output retrofits. For my efforts, the customer gets
The ions in the silversolution can only travel to the target and deposit there, when the cotton swap (in the stainless steel holder) TOUCHES the target. As soon as you take thw swab off, the deposition proces stops. Just fyi I enjoy these repair video's a lot, impressed with your skills. It puts me in a good mood. And mode 😉 Cheers from the Netherlands 👍🇳🇱
THAT’s my old man’s receiver!! I really love that heavy block of a tuner dial on that beast. And I’m happy to see a view from under the hood. Mine never had that color glow to it so yeah that LED mod is different. Oh my!? The days when knobs and dials had strings wrapped around cogs and strung all in and around the inside. Thanks for a very long life expectancy of these old Pioneers and Yamahas, nobody will ever need another newer model!! Those good ‘ol days, when they used those offset encoders and string wound around little pulley wheels, and those stacks of plated tuning capacitors with ceramic insulation. Single Damned tuning cap is the source of half of the cost and half of its weight…
Oh, what a joy to watch 👍 Learned a lot too… After watching 3-4 videos with Mark, this channel has gone straight to the top of my viewing list… 338k subs would have been more fitting… He might pass the 100k mark sooner than we think though… All the best from Denmark, Per.
Hi Mark, love you videos, I just found this one. I used to do industrial Gold plating on PCBs back in the day, I used Potassium Cyanide too. There was one golden rule - never have acids anywhere near Potassium Cyanide solution including distilled water that you've cleaned acidic products in, Hydrogen Cyanide gas is deadly (used in gas chambers), you really can't be too careful with it.
Awesome work mark, going that deep to clean the switches was a great show of dedication. In order to overcome the flickering lights once switching to led I build a small rectifier using 1N4001 diodes, dropping resistor if necessary and filtering capacitor (maybe 470 uF -1000 uF for those three lights). Hasn’t failed me yet. That regulator mod is a brilliant one.
Never seen anyone doing all that work to the contacts points, silver plating and all that. Fantastic work! And another good news is you got yourself a new subscriber! Hurray!
Now that was in depth,very few engineers would of gone that far, made for an interesting repair. I thought when you established the led fluctuations were down to the TX not having a stiff voltage,that a regulator would sort that,then you sorted it. Proper repair. Just to ad,engineers time is expensive,thats the reason most say some items are just beyond economic repair (BER), most customers dont want to spend over what the units worth. I like the old school equipment, and repair for the enjoyment factor,i'm retired & lucky to have that option. Thank you for your uploads Mark.
First time I've watched your videos Mark and I've loved it. I'm not technical at all but your style, presentation and know-how is brilliant. Thanks mate, you've got a new sub
Some great attention to detail, it's amazing how you make cleaning and repairing a switch interesting, a testament to the quality of your work and your character, your videos are a joy to watch.
Most impressive operation so far. Can't believe you plunged into murky waters so willingly and surmounted the many surprises in this operation. Great video 👍
I worked in a dept. store and sold a TON of these receivers...and the bigger siblings as well. They were quite good for the money and super attractive designs.
EM pinball machine contacts are made to last you could easily cut off switch contacts and solder them to where you need some I'm now hoping my QX949 has developed a faulty mains switch, went in box fully working, came out years later and won't even power up.
I learned over my many years in this business to look how well a tech keeps his iron tips. This tells me you take pride in the quality of your work. I just found your channel last night and have tons of fun watching. I have never plated anything and was amazed how well you made it work. Thanks for the fun.
Hooked on your channel Mark. They don't make 'em like that anymore. Beautiful green glow on the receiver. As Eevblog would say " a thing of beauty is a joy forever".
Enjoy seeing your subtle smile and laugh when you work, also heard a slight whistle too. Doesn't take much to make me happy, your work does that to me.
Hey Mark you are genius, & I do share those to my brother in India & my friends too though we are not technicians but love the way you always smile & laugh while enjoying your work to the maximum. Cheers !!!
Just found your channel riecently and your work and attitude are fantastic top notch.. not many people have your skill nor dedication.. you should pass this knowledge along to another.. wonderful.. just wonderful..
For tarnished contacts, if the item can be removed from the device, I always use either Evaporust or an equivalent product called Metal Rescue. They are designed to remove rust from iron but also work beautifully cleaning up brass and copper and will remove the blue crusties as well. Neither product will harm paint or plastics or any other metal, either is fantastic stuff. As for the burnt contacts, I've been faced with similar situations and have chosen to sacrifice another new switch or relay by taking out the contacts and replacing the burnt contacts since I don't have the facility to re-silver. In any case, sometimes the contacts are so far gone there's no chance of sanding them down and replacing the contact, if it's possible, is the only solution.
Another great vid Mark, I hope radio tech schools are using your YT clips for practical training! Great work with the contact plating - I must admit I'd probably just clean the contacts and re-assemble, customers just won't pay for lengthy repairs. A couple of points for young viewers (a) don't let your soldering iron anywhere near the dial cord - it vapourises it!, and (b) using the 3 terminal reg for the LED supply was a smart move, but ideally wrap the input/outputs with a 10uF tantalum cap to ground, as they tend to oscillate if not damped. Not want you want in a Rx. Thanks again Mark, your videos are totally engaging and educational.
Half of the time I haven't a clue as to what you are doing or talking about, I still applaud when the toast pops up out of the toaster 😉. Mesmerising stuff and a bloody genius at work.
Your knowledge has become a rare thing these days - which I think is worrisome - but a sight to behold. Absolutely brilliant, please keep teaching this knowledge. Absolutely brilliant!
Love electronics videos but yours are very well explained and don’t feel board at all, and the end is always happy and that’s the beauty of the TH-cam. I do have vintage HiFi stuff and everyone of them need some sort of attention and I think you can be the best person. Please continue to upload new videos
I don’t understand the first thing about electronics , but I find this fantastic and interesting to watch. It’s brilliant that people still have these skills, and are repairing this quality equipment. I can’t imagine how much all that testing and measuring equipment cost ? I’m looking forward to watching more having discovered the channel
@@HansDelbruck53 You’re kidding right? This man is every bit an electronics engineer and then some. Many elements of what you see might be classed as technicians work, but I can assure you he is way more than that. Analogue, RF, digital and many more design skills are demonstrated in his videos. And I by no means belittle the name of technician here either, as that is a deeply skilled class. But to have the knowledge demonstrated by Mark there are many years of varied design work gone into achieving that.
Watching your videos brought back memories of a couple of repairs I did (had been putting off) on both my 1980 vintage stereo components. First was the balance pot on my Sansui receiver, I had tried spray electronics cleaner but that didn't work as I could actually feel something inside had worn. I sourced a used pot online and installed it, success. The other was my Technics SL1600MKII turntable, it would power up but nothing else would happen. On disassembly I discovered the remnants of (IIRC) 2 belts that operated the tonearm functions. I sourced new belts in the form of correct sized "O" rings, again success and now my stereo once again rocks as it should. I still have one "lost cause" in the form of a Marantz SD8020 Compudeck, it never worked correctly with Marantz techs claiming they could find no faults with it
tony is a very happy camper mark i have had the nobs of a few times when cleaning the pots so they would come of easy funny enough i was just useing the amp before watching this video with a twin pair of memorex 505 speakers i got yesterday and she performed perfectly. i was a bit weird to see the amp disassembled but really interesting on the same note and if it needs any work again it will be coming back to you as you know i have the next item ready and waiting to be dropped of to you . plus it was nice to see a lot of them machines you use to help repair A GREAT VIDEO
Thats the type of Build Quality and Rugged components you could expect from the Electronics from the 70 and 80's. were built for easy servicing and repair, unlike the throw away and buy a new one mentality of the Manufactures of today, could be a cheap electronics or an expensive one.
My electronics instructor told me that the best connection is mechanical - meaning not using solder to transfer the signal. That's the reason for the wire wrapping and crimping before the solder. But that's all 70 year old-school. I know things are differnt today. In fact, in the old military applications, the square wire wrap created an oxygen free connection - and no solder needed on that post.
Beautiful work! Very thorough. although it looks like you forgot the support bracket or bridge on the power switch during reassembly, no problem. Thanks Mark!
You should add decoupling capacitors on the 78xx voltage regulator on both the input and output as close to the regulator as possible. They have a tendency to oscillate at a few hundred kilohertz without any decoupling.
I seem to recall over 1MHz on one occasion. 0.1uF and an electrolytic, across the in and the out, ideally. Maybe one of the new buck reg. LDO 78 lookalikes would be easier, no heat. Or a PWM RGB LED driver with WiFi + remote App. ...real disco lights, 70s meets GenZ.
My word you do love your craft ,fascinating to watch.I had a 450 that switch was arcing bypassed it threw a line switch for on off and sent it to the pawn shop .People are starting to realize how well those 70s were designed are going ga ga for them now 😅I see the prices going up now
I love the rock solid feel of these units from that era. Great video and skill beyond what I was expecting to see, and the plating, and microscope view wowzers.
I've just found your channel too. Mostly I have no idea what Im looking at or you're talking about, However I love this Channel. You would definitely be my Go-To man if ever I needed any Hi-Fi fixing. You explain and show things very clearly. Fascinating! Keep up the great work. I think you are a dying breed in this modern throw-away world. 5*
Fair play Mark, nice to keep the original switch going. Artisan electro-mechanical repair! I was going to do the same for my Arcam A60 power switch, then luckily found the exact same switch is still manufactured in the Uk, 45 years later!!
Good Job. Congratulations|! Years ago i repaired a Yamaha amplifier. It had the lamps series- connected and powered by a constant current circuit, which drove me crazy. A spare lamp was not available, so I replaced all lamps with LEDs.
Japanese HiFi was as much about the mechanical build and materials as they were about the electronic design. A repair worthy of the original philosophy of ‘built to last’. I noticed that the bearing support bracket/strap on the power switch was omitted during reassembly.
I had a receiver that looked just like that. In face, I can't spot any differences, although I don't remember the model nmber. My dad bought it at a garage sale for $5 in about 1983. It had apparently been dropped onto the front. Wasn't too bad, but it slightly bent the tuning knob shaft. I made a couple of repairs inside also, to the switches/pots. I don't recall the exact damage, but it did work pretty well. I took it to university and beyond. I do specifically remember, though, that even the original incandescent bulbs would pulse with the music. You're correct, it wasn't as sharp as those LED bulbs, but it was still there. It was an apparent "design feature." Love the videos!
The regulator for the Led backlighting is a great fix but I personally would have looked for a solution that just gets the LEDs to stop blinking, that way if something goes out of tolerance and the amplifier is drawing more current than it should, you will see that there's a problem developing before something goes really wrong. I have an amazing little amplifier that was built from a kit that was published in 1973 Electronics Australia and whoever built the one I now own did an amazing job on it's construction, anyway... It has an incandescent bulb to indicate power on and it used to blink with heavy bass loads and I found this to be very annoying until I found out that the poor thing was trying to tell me that it wasn't well and needed to be looked at! As it turns out, all the Elna capacitors were tired and were leaking DC even though they still looked perfect! So I replaced all the capacitors with the same capacity but went up in voltage tolerance to ensure a long service life. Just as well though, this amplifier is using Fairchild TO92 metal encapsulated transistors with the gold plating and were manufactured here in Clayton Victoria Australia (we don't make anything here anymore 😢) so finding an identical replacement for something that is now unobtainium would destroy it, incidentally these transistors predate the 2N3055's which were the next transistors released for high power applications... So this amplifier, the Playmaster 136 (15w per channel) sounds like nothing I have ever heard (and I have a lot of amplifiers (don't ask why lol) and I only got it because I wanted to gut it to fit 200W class D amplifier boards in it but I plugged it in and listened to it and couldn't believe what it was doing so I kept it, and thanks to it's clever design, it's power indicator lamp got my attention to save a small but significant piece of Australian electronic history... Lesson learnt, blinking lights aren't always a bad thing unless you have been speeding or run a red light in which case, naughty naughty 😮.
Love old amps like that glad it isnt class D now!! Google stereonet playmaster 136 articles... Forum thread with article showing replacement transistors. If yours fail , it IS fixable.
@PeterMalinkovsky Very interesting Peter! What was the part number of those unique Fairchild TO-92 transistors in your Playmaster 136? They sound like they'd be special signal transistors are they? Or driver transistors. What characteristic of these transistors do you think it could be that makes the amp sound so good? I built a Playmaster 40-40 back in the day which sounded real good, & in fact I still have the matching Playmaster AM/FM stereo tuner/clock that I built at the same time. The tuner still works well but there's one segment out on one of the led displays which I'm hoping is just a problem with the led display itself, which I could replace I guess, rather than a fault in the AY-8910 Clock chip, or whatever it was. But yeah. They were the good ole days building amps & chasing girls ay!
carefully made,quality ideo. stereo microscope.....class :-)impressive build quality by Pioneer...but not n league where makersincorporated good spark snuffers. you have a long way to go, Mark....a young guy, just to get UT hits, please don't use vicious chemicals - prefer to have you arund, eh? my achoolpal, Alex, electronics whizz, took som big voltages, developed MS, did'nt live to see 22, we can't always be repaired, like the Pioneer. sermon over. you and Techmoan aebest things on YT.all the best.
Bringing me back in time when I use to fix those units, with the ECG Cross reference Book the bible of Electronics back then. Though i hated re-wrapping those tuner chord going to the dial indicator. Loving the videos though thanks for the trip back in time
Very ambitious. However, going to this extent to clean switches makes sense if this is a hobby and you don't have to make a living doing this. I've worked on these receivers for years and never needed to do any more than schpritz the wafer switches with Deox to obtain a good result. As for the push switches, drilling a very small hole with a pin vise allows access to spray Deox in them for great results. As for the power switch, you can still find parts like this on the web. Again, all that works if this just a fun hobby. Nice work.
Those switch contacts remind me of the ignition coil points in the distributor of older vehicles, regular filing of those contacts and dwell angle gap to keep the ignition system functioning at peak. Those were the dayz, thankfully now hall-effect sensors did away with that menace, but created a whole new set of issues lol.
Hey mark you do magnificent repair jobs and we love to watch you with your beautiful smile. So please be careful about poisoning with chemicals they are silent killers always wear a proper mask it does really matter. And about the regulator I strongly recommend stepdown convertor over them , regulators are hot pains they always kill them self specially when input voltage is much higher than output. I know they are noisy and unfriendly with audio and radio circuits but I think they are acceptable for lighting.
This is all a bit of a blast from the past!! (I used to do tellies - well of course you can't really do much with them nowadays). I looked swiftly at an online pdf schematic and notice that it's an AC 8V take-off from the mains tranny that fed the original lamps. I don't know how the LED mods manifest themselves, but taking into account they can only be internally fed with DC, why not just mod it with a little bridge and a reservoir of some sort - it's AF that's affecting it so something in the 10uF to 100uF range perhaps?. That ought to stop it flickering. I bought an SX727 which is languishing in a spare room awaiting some attention and even have an LED kit for it, so I'll be looking to see if I get some of the same symptoms when / if I finally get around to it! Very interesting and slightly addictive channel! Very nice workshop too.
Hi. In some cases for rejuvenation of such Contact Points you can use the central electrode of a car sparkplug. Take the electrode out of a plug, file the electrode to a rivet and rivet it instaed of the worn one on the contact. It will last forever :) Been there, done that.
This is the best hifi repair restore technician in the world, breathtaking work .
Hello Mark! Silver plating the power switch contacts, after perfectly recreating dome shaped surfaces on both contacts... I have not seen anyone on TH-cam ever go through that much fine, precision work to restore a vintage power switch! You are clearly in a league of your own. Beautiful attention paid to every detail, to the point that you even consider the next repair person, when reattaching component leads speaks volumes to your ethic as well. I love your work. I am so happy that I found your channel. Please keep it up as this is really great stuff! Thank you for showing all of us how it should be done proper! Fred
Sony dvd
Absolutely agree :)
Oh yes! Agreed for sure! Subscribed!
There's a lot of great content being created like this channel i have a few other repair channels i like to watch while i'm waiting for new content to be released. I probably waste to much time watching all these channels lol.
@@JonnyMac351 What are your other favourite repair channels?
Normally Im not at all interested elecronics but Mark make it fascinating viewing. At 26:40 "I`ll just bend these legs a little bit, not to much, out of respect for people who might service this in the future." I doubt if there`s anyone out there who could even attempt this level of work. Simply amazing.
You are an Artist in electronics, mechanics, physics and chemistry. I am a a very old engineer and professor that armed valvular and transistor equipments in the 50´s to the 80´s. I admire you , and give me Hope in young people like you. Cheers from Patagonia, Argentina.
eh! un argentino a la curulla! yo armé equipos hibridos valvulas y transistores por los 70's! y todo empezó con la revista Lúpin a los 5 años! jajaj.
@@soulrobotics Excelente!!!!Saludos
These are some of the best repair videos on TH-cam. The silver plating was above and beyond what anyone would do. Subscribed!
+1. i was disappointed he didn't use gold however ;)
Silver conducts electricity better than gold
@@K-Effect ah, but gold doesn't tarnish
@@DavidFRhodes high purity silver tarnishes at about the same pace as high purity gold
Very minor quibble, as the contacts will slowly deteriorate over time from the effects of the electricity when contacts mate and break. It's nowhere near a sealed relay. Future repairmen will probably be more curious about the lighting regulator!
Jolly good show 👍
I love the engineering that went into making these old units. (I say 'old' reluctantly because I remember when these were the latest thing!) Made to last, and made to be repaired - something so sadly lacking in so much of today's tech. Just love the extra mile Mark always goes when restoring or repairing them. One of the very best techs on TH-cam for this kind of stuff.
They cost about a month's wages when they were new, they were very expensive.
I'd guess the cost of that service and repair work would far exceed it's actual value.
But it's possibly someones pride and joy.
"They certainly weren't skimping on cost when they made this", no, they weren't. That's why we loved Pioneer.
Mark, that re silvering of the contacts was a brilliant move! That is what I like about your channel. Inventive! Love it! Keep up the good work and your channel will grow, you are up there with the best!
Exactly my thoughts… just subscribed a few days ago…and after 3-4 videos Mend it Mark is at the top of my list… BR, Per (DK)
What a patient and resourceful person !
The joy of finding a Mark video that I forgot to watch. The guy is a genius and therapy!! Thank you Mark!!!!
I am from Brazil, and this is the best hifi repair restore technician in the world !!!!
And I always thought I went the extra mile, but silver plating the power switch contacts is almost unbelievable. Wow
Just awesome knowledge Mark. Thank you for the opportunity to join you.
Hi Mark, what a pleasure it is to watch a real pro working on this high quality old audio equipment. 👍
This is probably their best analog receiver lineup overall due to appearance, performance, and ease of service. All have discrete outputs save for the oddball SX-650 which uses SanKen SP-40W modules.
I just did an extremely comprehensive service and upgrade on an SX-650 including a full recap, new schottky rectifiers, retrofit OPA1611 opamps and discrete output retrofits. For my efforts, the customer gets
The ions in the silversolution can only travel to the target and deposit there, when the cotton swap (in the stainless steel holder) TOUCHES the target. As soon as you take thw swab off, the deposition proces stops. Just fyi
I enjoy these repair video's a lot, impressed with your skills. It puts me in a good mood. And mode 😉
Cheers from the Netherlands 👍🇳🇱
THAT’s my old man’s receiver!! I really love that heavy block of a tuner dial on that beast. And I’m happy to see a view from under the hood. Mine never had that color glow to it so yeah that LED mod is different. Oh my!? The days when knobs and dials had strings wrapped around cogs and strung all in and around the inside. Thanks for a very long life expectancy of these old Pioneers and Yamahas, nobody will ever need another newer model!! Those good ‘ol days, when they used those offset encoders and string wound around little pulley wheels, and those stacks of plated tuning capacitors with ceramic insulation. Single Damned tuning cap is the source of half of the cost and half of its weight…
Oh, what a joy to watch 👍 Learned a lot too… After watching 3-4 videos with Mark, this channel has gone straight to the top of my viewing list… 338k subs would have been more fitting… He might pass the 100k mark sooner than we think though… All the best from Denmark, Per.
Hi Mark, love you videos, I just found this one. I used to do industrial Gold plating on PCBs back in the day, I used Potassium Cyanide too. There was one golden rule - never have acids anywhere near Potassium Cyanide solution including distilled water that you've cleaned acidic products in, Hydrogen Cyanide gas is deadly (used in gas chambers), you really can't be too careful with it.
Awesome work mark, going that deep to clean the switches was a great show of dedication. In order to overcome the flickering lights once switching to led I build a small rectifier using 1N4001 diodes, dropping resistor if necessary and filtering capacitor (maybe 470 uF -1000 uF for those three lights). Hasn’t failed me yet. That regulator mod is a brilliant one.
How cheap of you Mark to just use silver! You should have gold plated them, LOL! 😂
Hearing the birds in the background was nice. That seems like such a peaceful workshop, coming from an automotive technician.
Never seen anyone doing all that work to the contacts points, silver plating and all that. Fantastic work! And another good news is you got yourself a new subscriber! Hurray!
Now that was in depth,very few engineers would of gone that far, made for an interesting repair. I thought when you established the led fluctuations were down to the TX not having a stiff voltage,that a regulator would sort that,then you sorted it. Proper repair. Just to ad,engineers time is expensive,thats the reason most say some items are just beyond economic repair (BER), most customers dont want to spend over what the units worth. I like the old school equipment, and repair for the enjoyment factor,i'm retired & lucky to have that option. Thank you for your uploads Mark.
First time I've watched your videos Mark and I've loved it. I'm not technical at all but your style, presentation and know-how is brilliant. Thanks mate, you've got a new sub
Some great attention to detail, it's amazing how you make cleaning and repairing a switch interesting, a testament to the quality of your work and your character, your videos are a joy to watch.
Absolutely!
Most impressive operation so far. Can't believe you plunged into murky waters so willingly and surmounted the many surprises in this operation.
Great video 👍
just found this channel -it's great!
I have a Pioneer Receiver from the same era - it's still awesome sounding. love watching you work.
That is dedication for perfection, workmanship par excellence.
Brought back memories. That was my first receiver when I was a teenager. Nice to see one has survived this long. Thanks for the memories.
I worked in a dept. store and sold a TON of these receivers...and the bigger siblings as well. They were quite good for the money and super attractive designs.
EM pinball machine contacts are made to last
you could easily cut off switch contacts and solder them to where you need some
I'm now hoping my QX949 has developed a faulty mains switch, went in box fully working, came out years later and won't even power up.
I learned over my many years in this business to look how well a tech keeps his iron tips. This tells me you take pride in the quality of your work. I just found your channel last night and have tons of fun watching. I have never plated anything and was amazed how well you made it work. Thanks for the fun.
The power switch contacts looked totally knackered - impressive repair. A regulator on the lights is the perfect solution.
My dad had a Pioneer turntable and amplifier when I was very young. Seeing the knobs and typeface on that receiver brought it all back
Hooked on your channel Mark. They don't make 'em like that anymore. Beautiful green glow on the receiver. As Eevblog would say " a thing of beauty is a joy forever".
Enjoy seeing your subtle smile and laugh when you work, also heard a slight whistle too. Doesn't take much to make me happy, your work does that to me.
Love your work mate. You’re the guy I’d want working on my gear. Keep ‘em coming!
Hey Mark you are genius, & I do share those to my brother in India & my friends too though we are not technicians but love the way you always smile & laugh while enjoying your work to the maximum. Cheers !!!
Back when engineering beautiful receivers made sense because there was good music to listen to on the radio.
Great job of restoration; however, you forgot to re-install the metal bracket on the back of the main power switch.
Just found your channel riecently and your work and attitude are fantastic top notch.. not many people have your skill nor dedication.. you should pass this knowledge along to another.. wonderful.. just wonderful..
For tarnished contacts, if the item can be removed from the device, I always use either Evaporust or an equivalent product called Metal Rescue. They are designed to remove rust from iron but also work beautifully cleaning up brass and copper and will remove the blue crusties as well. Neither product will harm paint or plastics or any other metal, either is fantastic stuff.
As for the burnt contacts, I've been faced with similar situations and have chosen to sacrifice another new switch or relay by taking out the contacts and replacing the burnt contacts since I don't have the facility to re-silver. In any case, sometimes the contacts are so far gone there's no chance of sanding them down and replacing the contact, if it's possible, is the only solution.
I use Milk of Magnesia (the stuff for upset stomachs) works a treat
I use Argon neutralated boron infused rice pudding mix.
Another great vid Mark, I hope radio tech schools are using your YT clips for practical training! Great work with the contact plating - I must admit I'd probably just clean the contacts and re-assemble, customers just won't pay for lengthy repairs. A couple of points for young viewers (a) don't let your soldering iron anywhere near the dial cord - it vapourises it!, and (b) using the 3 terminal reg for the LED supply was a smart move, but ideally wrap the input/outputs with a 10uF tantalum cap to ground, as they tend to oscillate if not damped. Not want you want in a Rx. Thanks again Mark, your videos are totally engaging and educational.
Love your spectrum analyser! What an absolute classic instrument, these still cost 2k on Ebay!
i just got to know your channel....first class in everything....what a joy..
Half of the time I haven't a clue as to what you are doing or talking about, I still applaud when the toast pops up out of the toaster 😉.
Mesmerising stuff and a bloody genius at work.
Your knowledge has become a rare thing these days - which I think is worrisome - but a sight to behold. Absolutely brilliant, please keep teaching this knowledge. Absolutely brilliant!
Quite right. Well said.
Love electronics videos but yours are very well explained and don’t feel board at all, and the end is always happy and that’s the beauty of the TH-cam. I do have vintage HiFi stuff and everyone of them need some sort of attention and I think you can be the best person. Please continue to upload new videos
Loved the needle/frequency adjustment detail. Thanks for showing that approach!
Glad I found your uTube channel mate
Well this is not just troubleshooting but craftsmanship. Awesome!
Very impressive work. That’s sure is dedication to your work. Big pat on the back for you mark.
“We’re not worthy”
I don’t understand the first thing about electronics , but I find this fantastic and interesting to watch. It’s brilliant that people still have these skills, and are repairing this quality equipment. I can’t imagine how much all that testing and measuring equipment cost ? I’m looking forward to watching more having discovered the channel
Exactly!😅
Excellent work Mark.
Absolutely amazing amount of work to get that thing working properly. Great video.
Vintage Japanese hi fi is so beautifully made and designed. Top work, sir!
Fantastic job and a very good video. You are a very skilled electronics engineer.
Technician
@@HansDelbruck53 You’re kidding right? This man is every bit an electronics engineer and then some. Many elements of what you see might be classed as technicians work, but I can assure you he is way more than that. Analogue, RF, digital and many more design skills are demonstrated in his videos. And I by no means belittle the name of technician here either, as that is a deeply skilled class. But to have the knowledge demonstrated by Mark there are many years of varied design work gone into achieving that.
Watching your videos brought back memories of a couple of repairs I did (had been putting off) on both my 1980 vintage stereo components. First was the balance pot on my Sansui receiver, I had tried spray electronics cleaner but that didn't work as I could actually feel something inside had worn. I sourced a used pot online and installed it, success. The other was my Technics SL1600MKII turntable, it would power up but nothing else would happen. On disassembly I discovered the remnants of (IIRC) 2 belts that operated the tonearm functions. I sourced new belts in the form of correct sized "O" rings, again success and now my stereo once again rocks as it should. I still have one "lost cause" in the form of a Marantz SD8020 Compudeck, it never worked correctly with Marantz techs claiming they could find no faults with it
It’s amazing the wealth of knowledge in this young man’s brain
I love the happy way you work. Fun videos.
I still use a Pioneer AV Receiver SX 737 still going strong all these years with no trouble.
tony is a very happy camper mark
i have had the nobs of a few times when cleaning the pots so they would come of easy
funny enough i was just useing the amp before watching this video with a twin pair of memorex 505 speakers i got yesterday and she performed perfectly.
i was a bit weird to see the amp disassembled but really interesting on the same note and if it needs any work again it will be coming back to you as you know i have the next item ready and waiting to be dropped of to you .
plus it was nice to see a lot of them machines you use to help repair
A GREAT VIDEO
Thats the type of Build Quality and Rugged components you could expect from the Electronics from the 70 and 80's. were built for easy servicing and repair, unlike the throw away and buy a new one mentality of the Manufactures of today, could be a cheap electronics or an expensive one.
wow that is a sophisticated way of repairing electronics. wish you are close to here in Australia to send you my devices that need some taking care.
My electronics instructor told me that the best connection is mechanical - meaning not using solder to transfer the signal.
That's the reason for the wire wrapping and crimping before the solder. But that's all 70 year old-school. I know things are differnt today.
In fact, in the old military applications, the square wire wrap created an oxygen free connection - and no solder needed on that post.
"It smells strong, and it's deadly... oh, ICE CREAMS!"
Beautiful work! Very thorough. although it looks like you forgot the support bracket or bridge on the power switch during reassembly, no problem. Thanks Mark!
Have just found your channel, really enjoying binge watching the videos
You should add decoupling capacitors on the 78xx voltage regulator on both the input and output as close to the regulator as possible. They have a tendency to oscillate at a few hundred kilohertz without any decoupling.
I seem to recall over 1MHz on one occasion. 0.1uF and an electrolytic, across the in and the out, ideally. Maybe one of the new buck reg. LDO 78 lookalikes would be easier, no heat. Or a PWM RGB LED driver with WiFi + remote App. ...real disco lights, 70s meets GenZ.
No need for 0.1uf input cap if the reg is near the filter cap. Also it will oscillate for sure if you put really low esr caps on the output.
first class work Mark,and a very interesting video. well done to you.
LOve your videos Mark,so glad i found your channel,thank you for your informative work and joyful approach to fixing things x
Nice work Mark!
Thanks! Great to see you on here!
You have a very pure soul and I always enjoy watching you
Your follower from Palestine ❤
I’m glad to learn I’m not the only one who uses a crescent wrench 🔧 on those control mounting nuts. Great job on the master mode switch.
My word you do love your craft ,fascinating to watch.I had a 450 that switch was arcing bypassed it threw a line switch for on off and sent it to the pawn shop .People are starting to realize how well those 70s were designed are going ga ga for them now 😅I see the prices going up now
I love the rock solid feel of these units from that era. Great video and skill beyond what I was expecting to see, and the plating, and microscope view wowzers.
Thanks for your videos and help. To the community of vintage.
You're very skilled Mark, my compliments!
I've just found your channel too. Mostly I have no idea what Im looking at or you're talking about, However I love this Channel. You would definitely be my Go-To man if ever I needed any Hi-Fi fixing. You explain and show things very clearly. Fascinating! Keep up the great work. I think you are a dying breed in this modern throw-away world. 5*
you're a legend Mark .. you should get an olympic gold mate !!
I could watch you all day, thank you for such great content!
Fair play Mark, nice to keep the original switch going. Artisan electro-mechanical repair! I was going to do the same for my Arcam A60 power switch, then luckily found the exact same switch is still manufactured in the Uk, 45 years later!!
Good Job. Congratulations|!
Years ago i repaired a Yamaha amplifier. It had the lamps series- connected and powered by a constant current circuit, which drove me crazy.
A spare lamp was not available, so I replaced all lamps with LEDs.
Japanese HiFi was as much about the mechanical build and materials as they were about the electronic design. A repair worthy of the original philosophy of ‘built to last’. I noticed that the bearing support bracket/strap on the power switch was omitted during reassembly.
I had a receiver that looked just like that. In face, I can't spot any differences, although I don't remember the model nmber. My dad bought it at a garage sale for $5 in about 1983. It had apparently been dropped onto the front. Wasn't too bad, but it slightly bent the tuning knob shaft. I made a couple of repairs inside also, to the switches/pots. I don't recall the exact damage, but it did work pretty well. I took it to university and beyond. I do specifically remember, though, that even the original incandescent bulbs would pulse with the music. You're correct, it wasn't as sharp as those LED bulbs, but it was still there. It was an apparent "design feature." Love the videos!
The regulator for the Led backlighting is a great fix but I personally would have looked for a solution that just gets the LEDs to stop blinking, that way if something goes out of tolerance and the amplifier is drawing more current than it should, you will see that there's a problem developing before something goes really wrong.
I have an amazing little amplifier that was built from a kit that was published in 1973 Electronics Australia and whoever built the one I now own did an amazing job on it's construction, anyway... It has an incandescent bulb to indicate power on and it used to blink with heavy bass loads and I found this to be very annoying until I found out that the poor thing was trying to tell me that it wasn't well and needed to be looked at! As it turns out, all the Elna capacitors were tired and were leaking DC even though they still looked perfect! So I replaced all the capacitors with the same capacity but went up in voltage tolerance to ensure a long service life. Just as well though, this amplifier is using Fairchild TO92 metal encapsulated transistors with the gold plating and were manufactured here in Clayton Victoria Australia (we don't make anything here anymore 😢) so finding an identical replacement for something that is now unobtainium would destroy it, incidentally these transistors predate the 2N3055's which were the next transistors released for high power applications...
So this amplifier, the Playmaster 136 (15w per channel) sounds like nothing I have ever heard (and I have a lot of amplifiers (don't ask why lol) and I only got it because I wanted to gut it to fit 200W class D amplifier boards in it but I plugged it in and listened to it and couldn't believe what it was doing so I kept it, and thanks to it's clever design, it's power indicator lamp got my attention to save a small but significant piece of Australian electronic history...
Lesson learnt, blinking lights aren't always a bad thing unless you have been speeding or run a red light in which case, naughty naughty 😮.
Love old amps like that glad it isnt class D now!! Google stereonet playmaster 136 articles... Forum thread with article showing replacement transistors. If yours fail , it IS fixable.
@PeterMalinkovsky Very interesting Peter! What was the part number of those unique Fairchild TO-92 transistors in your Playmaster 136? They sound like they'd be special signal transistors are they? Or driver transistors. What characteristic of these transistors do you think it could be that makes the amp sound so good?
I built a Playmaster 40-40 back in the day which sounded real good, & in fact I still have the matching Playmaster AM/FM stereo tuner/clock that I built at the same time. The tuner still works well but there's one segment out on one of the led displays which I'm hoping is just a problem with the led display itself, which I could replace I guess, rather than a fault in the AY-8910 Clock chip, or whatever it was.
But yeah. They were the good ole days building amps & chasing girls ay!
That was brilliant, I'm really enjoying watching you work, thanks.
carefully made,quality ideo. stereo microscope.....class :-)impressive build quality by Pioneer...but not n league where makersincorporated good spark snuffers. you have a long way to go, Mark....a young guy, just to get UT hits, please don't use vicious chemicals - prefer to have you arund, eh? my achoolpal, Alex, electronics whizz, took som big voltages, developed MS, did'nt live to see 22, we can't always be repaired, like the Pioneer. sermon over. you and Techmoan aebest things on YT.all the best.
Such a talented likeable guy! 5 *****!
Bringing me back in time when I use to fix those units, with the ECG Cross reference Book the bible of Electronics back then. Though i hated re-wrapping those tuner chord going to the dial indicator. Loving the videos though thanks for the trip back in time
Very ambitious. However, going to this extent to clean switches makes sense if this is a hobby and you don't have to make a living doing this.
I've worked on these receivers for years and never needed to do any more than schpritz the wafer switches with Deox to obtain a good result.
As for the push switches, drilling a very small hole with a pin vise allows access to spray Deox in them for great results.
As for the power switch, you can still find parts like this on the web.
Again, all that works if this just a fun hobby.
Nice work.
I had one of those Bigtrak toys along tine ago as shown in the intro. Reall fond memories ,
Those switch contacts remind me of the ignition coil points in the distributor of older vehicles, regular filing of those contacts and dwell angle gap to keep the ignition system functioning at peak. Those were the dayz, thankfully now hall-effect sensors did away with that menace, but created a whole new set of issues lol.
Just brilliant to watch it's a shame he doesn't tell you how much it cost for the repairs on each video.
Brilliant! Thanks for brightening my day with your high mood. Koray from Ankara
Hey mark you do magnificent repair jobs and we love to watch you with your beautiful smile. So please be careful about poisoning with chemicals they are silent killers always wear a proper mask it does really matter. And about the regulator I strongly recommend stepdown convertor over them , regulators are hot pains they always kill them self specially when input voltage is much higher than output. I know they are noisy and unfriendly with audio and radio circuits but I think they are acceptable for lighting.
This is all a bit of a blast from the past!! (I used to do tellies - well of course you can't really do much with them nowadays).
I looked swiftly at an online pdf schematic and notice that it's an AC 8V take-off from the mains tranny that fed the original lamps. I don't know how the LED mods manifest themselves, but taking into account they can only be internally fed with DC, why not just mod it with a little bridge and a reservoir of some sort - it's AF that's affecting it so something in the 10uF to 100uF range perhaps?. That ought to stop it flickering.
I bought an SX727 which is languishing in a spare room awaiting some attention and even have an LED kit for it, so I'll be looking to see if I get some of the same symptoms when / if I finally get around to it!
Very interesting and slightly addictive channel! Very nice workshop too.
Sou da região sul do Brasil, além de gostar muito do seu trabalho, também quero parabenizá-lo por sua simpatia e simplicidade!
Hi. In some cases for rejuvenation of such Contact Points you can use the central electrode of a car sparkplug. Take the electrode out of a plug, file the electrode to a rivet and rivet it instaed of the worn one on the contact. It will last forever :) Been there, done that.
What a great way to spend my morning. Thank you.😊