I went to the wreckers last week to get a spare tire for my hot rod. After I found a tire, I did a little bit of snooping around, and came across this old van that had a bunch of hvac junk inside, that had this big old stereo hanging out the back. I took a closer look, and it was a Kenwood KR-7070 A. About the only thing that was keeping it from falling on the ground was that the cord was hung up under all the junk. I went to the side door to rearrange some things to untangle it, and there was a Pioneer sx3600 in there. After getting the cord free, I just left everything there because my hands were already full, and the Kenwood was quite heavy. I paid for the tire and left. I got a mile down the road and decided to go back and ask if I could go grab it. The young guy said sure. I went and got it, and carrying that thing an eighth of a mile was a bit of work. I set it down in the office for him to see it, the veneer was all lifted on the cabinet, and it was in sad looking shape. When he got off the phone, he took a quick look and said take it. I was a happy camper. I got home, and opened it up, and surprisingly, it didn't look too bad inside. A light blow with compressed air, and an external cleanup, was all I did. I made up a dim bulb tester, and plugged it in, and turned it on, and amazingly it lit up and nothing blew. Everything works fine, except the fm stereo is garbled on every station, with barely any signal on the meter. You can get some stations to come in perfectly clear, but you have to turn the volume up pretty high, just to hear them. I re glued all the veneer and re stained the cabinet, and it looks great now. I wish you lived near me, I would bring it to you, and give you the go ahead like your customer on this machine you are working on did. Oh yeah, I went back a couple of days later to get a scissor jack, and grabbed the pioneer. Another freebee.
Great video! Common for the power switch on the more powerful vintage receivers to be arced and burned. This is because of the large current inrush from their large power transformers. A way to cure that is to install a soft-start device that have a relay on them. That receiver would be a good candidate for a soft-start. Maybe that would something the owner would want being the nice condition. With a soft-start, the switch you repaired might never fail again since the switch would only be switching a milliamps instead of the very brief possibly 20+ amp surge.
@@eDoc2020 Simple and appropriate for devices that have a relativity constant and predicable power draw. An amplifier can be sitting idle drawing < 100 watts idle and then draw 800-1000 watts when driven fully, exactly like my old Kenwood KR-9600 receiver. Hard to size up the thermistor for such a variable load + the most important part is the power switch is still carrying all the power. Whereas with a soft start board the power switch would now only carry milliamps of current and perhaps last indefinitely. Those switches if they can still be found (used) are getting pricey and preserving them as well as the receiver's transformer and power supply from massive surges makes more sense to me. When I recap my Kenwood KR-9600 and other's, I will be installing soft-start boards in all of them. I already use inrush limiters on smaller electrons like radios.
Nice job! Most unused switches from this era can have issues, even alps. Elna and Matsushita caps from 70s seem to last incredibly well. Grey Elna's are worth checking. Christmas light idea is excellent.
I had that receiver, but in rough shape, the toggle and rotary switches were all dirty, and sprayed all with tuner cleaner. I liked this receiver better because of the backlighting was softer than my SA5370 and the led flashing with the sound output, I thought it was impressive for the time, 1978, a big difference one year made as the 5370 came out in 1977, I sold both at a flea market, regrettably getting 10$-15$ each in the late 80s. I wish I kept one at least
your videos are a Godsend. I have both an SA 700 and a SA 800. when the flip switches are oxidized you cant get the reciever to put out any sound. the volume pot is hidden under a small circuit board and really hard to get to. i tried several times and couldnt get the volume to stop sounding scratchy, until i watched your video . finally i am scratch free on volume and loving it. thanks.
Yeah. I was thinking that Green LED for Safety SHOULD mean "OK", ie Green is good. Also goes to show how having somebody else (cognizant) check your reasoning can be useful.
I have a Technics SA-600 receiver, these things are phenomenal, the biggest complaint I have is that the switches and pots oxidate quite easily and get noisy. My receiver is also losing the ability to decode FM stereo, I remember I tweaked some pot inside a few years ago (don't remember which one but I think it was the VCO 19 kHz adjuster, it was near the multiplex decoder IC) and it worked for a while, I guess it's probably some drifting capacitor. I'll have to take another look at it some day.
You could use a Triac to handle the turn on voltage, and the switch becomes the low voltage trigger. This extends the original power switches' life exponentially even one in marginal condition. Plans are all over the place showing this and it's an easy mod on these old receivers. Cheers!
I had an interesting failure of a switch the other day. A Sony tfm8000w’s power switch was intermittent and come to find out the little contact jumpers inside it had lost spring tension. No amount of cleaning would make it work. I ended up taking the jumpers out of a spare switch assembly I had and installed them into the Sony switch and it’s fixed.
I can build a engine and install it in a car blindfolded but when it comes to this kind of work specially soldering and finding whats wrong in a sea of little transistors and capacitors i take my hat off to these guys,i couldn't solder 2 pieces together if my life depended on it and hes doing it sideways,lol
Might be worth soldering a Bidirectional TVS Diode externally across the switch. Essentially a zener diode made for AC that clamps the positive or negative voltage spike when the contacts separate. Should drastically reduce the arcing and extend the life of the already worn contacts.
Good idea, i am trying to tackle a problem where the customer is complaining about a ‘click sound’ in the speaker when he switches it off, i’ve increased the cap over the switch but can really get rid of it. Which one would you use? 1,5ke250ca or 300ca (230V country)
@@martijnappeldoorn8686 You might be better off with a relay that disconnects the speakers as soon as the AC voltage cuts out; there are ready made PCBs on ebay that do just that, using an additional 12V transformer in parallel with the main one.
@@paulb4661 that is already present Paul, if i increase the cap to circa 1uF it ‘s gone , but then the amp doesn’t switch off completly so i think i will try a tvs diode see if that helps
Actually I like the headlight that has the LED that wraps all the way around the front of your head. Those work great. You don't have to adjust anything.
The one I'm talking about you don't even have to turn your head. Only problem is if there's somebody in the room with you it would bother the hell out of them.
I have a Realistic STA-2270, 65 watt per channel, and after repairing the power switch the second time, because it had welded together, I decided to avoid a third repair. It is a pain to get to. The switches for that are also non-existent. I re-wired it to use a relay as the power switch so now the power switch only has to handle the current from the relay coil, much less than it was handling. So far so good. The only thing I sort of goofed on was I used the wrong side of the relay so the on/off position of the switch is the opposite of what it was.
If you used the NC instead of the NO relay contacts it might be worth fixing. You'd be wasting power whenever the unit is turned off and if there are power glitches it will power on unnecessarily.
I was just wondering is it possible to swap out the power switch with one of the lesser used switches? I thoroughly enjoy your videos. Keep up the great work !
I like that this has the power transistors rather than those Darlington packs...I think that's what you call em right? I have an SA200 that I bought in 79 that I have not had to open yet and use everyday almost. I use the preamp mainly for archiving vinyl digitally for customers the last 20 years. A great workhorse! One reason mine is still going on without a hitch is because I always keep it on.....never gets shut off.
if you take the aluminum face plate off of this you most likely wont be able to get it to go back on. there are plastic inserts that fit around all the knob controls - you have to use an 11mm deep socket to remove the plastic inserts. they look like a thimble that would fit over your thumb. then the cover will go on. then put the sockets into the face of the unit and use the 11mm nuts to hold them in place. hand tighten the nuts. push the knobs back on . this will throw you for a loop
Would you go as far as asking the owner if they would consider fitting a soft start circuit? That would certainly stop the on/off switch from burning up from inrush current.
I personally like the 'christmas lights in series' much more than LED lights. I'm not a fan of LED light frequency it emits. :) Thanks for showing your method of installing them.
I agree, incandescent looks better. I use incandescent in my giant lit grandfather clock. They are on a dimmer so they last forever and are long filament tubular lamps the light the pendulum cabinet. It's a 20,000.00 clock that i inherited.
@@SPINNINGMYWHEELS777 It is a very limited edition made by rideway. The woman that bought it when it was new paid 16,000.000 it as a special order. It's part of the Biltmore collection to represent each state room in the Biltmore mansion. The mansion has 250 rooms and they built one clock to represent each one. The one i have is 021 out if 250 made. That makes it rare. It is huge. Will not fit in rooms with 8' ceiling as it is about 8' 4" base to top. Hand crafted and the pendulum base it lot up. Younger generation don't appreciate these massive clocks. My son thinks i should sell it. I laughed. Prices go up and down on these but one thing for sure they all all go up in value as they get older. Since mine is a very limited run it should increase much faster then a regular production run. What makes this one special, besides the serial plate is the size. About 6" taller than the regular clocks which come in a little under 8' so they fit in normal 8' ceiling rooms.
Does anyone know who made Realistic stereo receivers? Was it their own product? I remember having to replace the stereo indicator bulb located on the tuner pointer. I had to paint that red to match the original. This receiver surprisingly out performed others that I owned.
The way capacitor testers read capacitance, they use the time it takes to charge to a certain voltage to calculate capacitance. Contrary to what many people believe, capacitors that read over their rated capacitance are more likely to have developed internal shorting and are going bad. When a capacitor has internal shorting, the indicated value by the tester won't be accurate and is likely to be much lower than indicated. An 18 year old electrolytic that reads above it's rated uf is likely going bad.
This is why ESR is a more accurate read as it measures the equivalent series resistance using ac voltage and current when capacitors dry up the ESR will tend to climb. Measuring the microfarad however also gives you a good indication of where the capacitor is most electrolytics are 20% tolerance at a minimum. so a 100 microfarad capacitor will typically measure anywhere between about 90 and 120 so that range you're in good shape if you are measuring a 100 micro farad capacitor and it was showing 400 microfarads then you've got a serious issue with it. What I found however is the opposite if the cap has got an internal short it measures low so that 100 microfarad capacitor might be measuring 68. I think different meters work on different principles and some do a better job than others. I had a capacitor go dead short once that one was tricky because you put the ESR meter on it and it's showing like 0.01 which look to be very good or 0.03 or whatever but it looked to be very good however put the capacitor meter on it and it showed low but the ohm meter on it it's showed short. I have found however that vintage cap from the late '70s and into the early '80s generally tend to last a long time. The reason for that is a lot of them used PCB oil which was very stable. Toxic but stable, and these caps generally tended to last an extremely long time unless they were physically damaged. By physically damaged I mean the leaves manhandled when they were being installed or the top squeeze with the pair of pliers or something when it was being installed or someone working on it bending parts back and forth to get access to another component that can break the seal and allow the electrolytic to escape. Cops made after the mid 80s and well into the 90s however were horrible they changed the formulation to make them environmentally friendly and in the process made them extremely unreliable. They also went to a water based electrolytic which as you know water boils at 100 Celsius. So even getting close to the boiling point pressure starts to build inside them if you go over their rating voltage or too high in frequency the water will boil and it will blow the safety vent. No I'm not saying old caps don't fail they certainly do it's just that their failure rate is much lower than the mid 80s to late 90s which were a very bad time to be an electrolytic capacitor
@@12voltvids Thanks for information. Yes you are right about electrolytic caps. Sorry my bad. I was thinking of those small non-electrolytic caps used in old vintage tube gear that develop DC resistance (not ESR). Most of the time when measuring the value for a electrically leaky paper or film cap it is over value on any of my capacitance meters. Of course if it has a dead short it won't read much/any capacitance at all
@@multicyclist yeah the paper caps used in tube gear they all have to be replaced no matter how they test. Even if you use a high voltage breakdown tester which is really the only way to test them which is a tester that applies 500 or 600 volts to the capacitor and measures for any DC leakage even testing them that way they can test good today and tomorrow develop leakage. Because vacuum tubes are high impedance devices it takes very little leakage to pull a tube into over conducting which will red plate it and damage the tube and damage any other components that may be in that circuit like transformers. When I see vacuum tube gear I don't even check the Caps I just change them. I collect vintage radios and everyone that I've got I've changed out all the caps in the coupling circuits and don't even bother testing them. The problem with the paper caps is acid in the paper when it was made during the bleaching operation causes the paper to eventually become conductive.
Considering that the power switch had a lot of damage from arcing, maybe it would have been worth swapping the cap that is across the power switch, it may have went down in value.
This is 40 year old nutrol with freon tf solvent. It is superrior to the new stuff. I have deoxit as well but i am pissed at the company for disqualifying me from the last contest because they determined that multiple people were using vpn to vote for me and the guy in second place. So why would i promote them. I say fuck em, I can't control what others do.
As always remove the pots and switches, disassemble them, cleaning with a fibre brush, apply contact grease and there we go for the next 10+ years. Everything else is mumpitz. OK, I also would put a new Power switch in if contacts are burned. Of course, It is all a matter of time and what a Customer is willing to pay for. I do restore Profi Studio Equipment and People see it also as an asset. I love your Workshop BTW. This is a place where someone works and it is alive. Greetings from Devon.
@@telegraphhill803 removing the switches runs the real risk that the plastic will shatter. Good contact cleaner with lubricant works very well. Unfortunately the modern environmentally friendly cleaners are nothing compared to the old cleaners (I have 40 years old cans of cleaner when the good stuff was still made). Nutrol used to me the best. It was devoloped by the Telecom industry for cleaning stroger and crossbar switches and keep them clean. Chemtronix tun-o-power was another excellent cleaner with. Very fine grit that would polish switch contacts. They has pumice (volcanic ash) in it.
To bad you didn’t catch that bad switches right away but if you didn’t change those capacitors it would have probably been trouble down the road. Great repair! I started repair on a Marantz PMD 200 last night, oh my trying to get in to change the belts is a nightmare which you probably already know.
Curious what the original bulbs would have looked like, were they just painted or some interesting metallic coating inside? Apparently the pinball guys use "Dip Coating Bulb Paint" or "Bulb Dipping Paint"
You can dip them in a tinted laquor. Pale green would have been the original color.I highly doubt the owner will even know what the original looked like because it is highly unlikely he ever saw this unit in operation.
I had a question, i have a Technics unit but its modern, it has A and B speakers and on the B side the left one has this issue where it will quit working and if you wiggle it it comes back on then it goes out again etc,doesn't take much to make it go out, what could that be and ball park figure how much would it cost to fix? its a nice unit, id like to keep it, i took the top cover off once but those banks of speakers are buried and i didn't see anything that stood out as being loose or nothing, thank you for your time.
dollar store enamel paint (For nails) works very well if you like to match the bulb color - once it dries it's on good. just don't use an opaque color LOL
Hoping you can help- restoring an SA700 and someone has previously run a 47uf cap (on the back of the pcb no less) from the bottom leg of C450 (normally unused) over to R205. Can you tell me what this was intending to accomplish? Thanks so much in advance.
They bridged the cap over. Probably because the seevicer didnt have yhe exact replacement or one they had wouldn't fit. Very common repair procedure. Used to see that done all the time when stuff came in that had been previously serviced. Very often done on the large multi stage chaasis caps. May have 4 caps inside and 1 went bad so yhe tech wpuld cit off the bad lug and stick an external. I have done that on omd tube radios.
Amazing answer and thanks for the quick response. If I'm doing a full recap, would you recommend just replacing the (very old) cap in the exact same fashion? Or should the problem be resolved with all new electrolytics? Thanks again for the information and fantastic video!
@@marshallsanchez2070 if you are changing them all just install them the way they originally were. You will notice a difference in sound. If you are used to the sound that it produces now you may or may not be happy with the new sound as it will sound different. This is primarily due to the difference in chemestey of the electrolytic between old oil based caps and new water based caps. Even if they have the same value they have different charistics which will change the "color" of the sound. Some like it, others hate it. I had a guy pay me a second time to put all the old caps (that he took away) afyey I did a full recap a number of years ago. He didn't like the new sound. Said it was harsh.
I do have *one* more question that I ask because I've never really gotten a straight answer from anyone else... Is there any trick to accessing the bottom of the 15k power caps? The only thing I've seen is someone suggesting drilling holes in the plate thats covering them. Is that your recommendation as well? Thanks again.@@12voltvids
Hi Dave, I sometimes use a fine point marker, yellow color and mark a dot on the circuit board, if I can reach it with the marker and mark the minus side of the capacitors on the board, maybe that would be helpful for you ,great video!
Someone's been using the fast forward button haven't they? The reason it didn't work had nothing to do with the caps. The reason it didn't work was because the tape monitor switch was so badly oxidated that no signal was making through it even when I flipped it a few times at the beginning no signal was making it through it. I got thrown off track initially because the green light that says safety I was thinking that that was an indicator that it was in a fault mode but that's actually not the case that light comes on when it's working it goes out if it's in protection, and the fact that none of the dial lights were lighting up I was thinking power supply issue but the dilates were lighting up because they were all burned out. I changed all the caps still had no sound and it just happened to as it was firing up one time off camera I heard a little bit of sound come out of one of the speakers momentarily. I then started flipping the switches back and forth and heard a little scratch on the switch and then realized the problem was actually the switch itself both the record out switch and the tape monitor switch we're a really bad shape and it took a lot of cleaning to get them to actually perform properly. The volume control is also scratchy but the other controls were all fine as were all the other switches with the exception of the power switch
Sorry me,I watched it through all the intermittent issues with the switches and main on off but missed your diagnosis some how I tend to see all the way through real time as your such a good host.
People will pay out the nose for these old Technics in online auctions. I say let them have them. Even back in the late 70's when they were new you had to tune them up every year or suffer from the dirty switch and knob problems.
Appears FrankFurter C. Is the comments critic! But FrankFurter C. has a channel with ZERO content! Time for Frankie Boy to do a tear down. repair, and re-assemble video!
I love his work to the point when explaining what's the issue with devices
I went to the wreckers last week to get a spare tire for my hot rod. After I found a tire, I did a little bit of snooping around, and came across this old van that had a bunch of hvac junk inside, that had this big old stereo hanging out the back. I took a closer look, and it was a Kenwood KR-7070 A. About the only thing that was keeping it from falling on the ground was that the cord was hung up under all the junk. I went to the side door to rearrange some things to untangle it, and there was a Pioneer sx3600 in there. After getting the cord free, I just left everything there because my hands were already full, and the Kenwood was quite heavy. I paid for the tire and left. I got a mile down the road and decided to go back and ask if I could go grab it. The young guy said sure. I went and got it, and carrying that thing an eighth of a mile was a bit of work. I set it down in the office for him to see it, the veneer was all lifted on the cabinet, and it was in sad looking shape. When he got off the phone, he took a quick look and said take it. I was a happy camper. I got home, and opened it up, and surprisingly, it didn't look too bad inside. A light blow with compressed air, and an external cleanup, was all I did. I made up a dim bulb tester, and plugged it in, and turned it on, and amazingly it lit up and nothing blew. Everything works fine, except the fm stereo is garbled on every station, with barely any signal on the meter. You can get some stations to come in perfectly clear, but you have to turn the volume up pretty high, just to hear them. I re glued all the veneer and re stained the cabinet, and it looks great now. I wish you lived near me, I would bring it to you, and give you the go ahead like your customer on this machine you are working on did. Oh yeah, I went back a couple of days later to get a scissor jack, and grabbed the pioneer. Another freebee.
Great video! Common for the power switch on the more powerful vintage receivers to be arced and burned. This is because of the large current inrush from their large power transformers. A way to cure that is to install a soft-start device that have a relay on them. That receiver would be a good candidate for a soft-start. Maybe that would something the owner would want being the nice condition. With a soft-start, the switch you repaired might never fail again since the switch would only be switching a milliamps instead of the very brief possibly 20+ amp surge.
My question too: why not upgrade with such a module?
More simple than a relay-based module is an NTC thermistor / inrush current limiter (ICL).
@@eDoc2020 Simple and appropriate for devices that have a relativity constant and predicable power draw. An amplifier can be sitting idle drawing < 100 watts idle and then draw 800-1000 watts when driven fully, exactly like my old Kenwood KR-9600 receiver. Hard to size up the thermistor for such a variable load + the most important part is the power switch is still carrying all the power. Whereas with a soft start board the power switch would now only carry milliamps of current and perhaps last indefinitely. Those switches if they can still be found (used) are getting pricey and preserving them as well as the receiver's transformer and power supply from massive surges makes more sense to me. When I recap my Kenwood KR-9600 and other's, I will be installing soft-start boards in all of them. I already use inrush limiters on smaller electrons like radios.
Nice job! Most unused switches from this era can have issues, even alps. Elna and Matsushita caps from 70s seem to last incredibly well. Grey Elna's are worth checking. Christmas light idea is excellent.
I'm sure that the new caps that I just put in which we're all Rubicon but they will fail to gain before the other ones.
I had that receiver, but in rough shape, the toggle and rotary switches were all dirty, and sprayed all with tuner cleaner. I liked this receiver better because of the backlighting was softer than my SA5370 and the led flashing with the sound output, I thought it was impressive for the time, 1978, a big difference one year made as the 5370 came out in 1977, I sold both at a flea market, regrettably getting 10$-15$ each in the late 80s. I wish I kept one at least
your videos are a Godsend. I have both an SA 700 and a SA 800. when the flip switches are oxidized you cant get the reciever to put out any sound. the volume pot is hidden under a small circuit board and really hard to get to. i tried several times and couldnt get the volume to stop sounding scratchy, until i watched your video . finally i am scratch free on volume and loving it. thanks.
A Great bit of kit, I have an SA631 Tape Deck & love it.
Receiver sounds beautiful
I repaired a SA-500 with distorted sound/rice Krispies.
Bad drivers were the culprit.
Amazing sounding receivers!
Cooool ! Never seen a protection light on this era amp - but never had a Technics of that time period.
Yeah. I was thinking that Green LED for Safety SHOULD mean "OK", ie Green is good. Also goes to show how having somebody else (cognizant) check your reasoning can be useful.
Informative and entertaining as usual. Cheers matey.
Thanks a lot for this vídeo ☺️👋saludos de bajá California MÉXICO 🇲🇽🇲🇽
I have a Technics SA-600 receiver, these things are phenomenal, the biggest complaint I have is that the switches and pots oxidate quite easily and get noisy. My receiver is also losing the ability to decode FM stereo, I remember I tweaked some pot inside a few years ago (don't remember which one but I think it was the VCO 19 kHz adjuster, it was near the multiplex decoder IC) and it worked for a while, I guess it's probably some drifting capacitor. I'll have to take another look at it some day.
Great work bro
You could use a Triac to handle the turn on voltage, and the switch becomes the low voltage trigger. This extends the original power switches' life exponentially even one in marginal condition. Plans are all over the place showing this and it's an easy mod on these old receivers. Cheers!
I had an interesting failure of a switch the other day. A Sony tfm8000w’s power switch was intermittent and come to find out the little contact jumpers inside it had lost spring tension. No amount of cleaning would make it work. I ended up taking the jumpers out of a spare switch assembly I had and installed them into the Sony switch and it’s fixed.
i have a realistic that is in prestine condition and sounds great love the old recievers
Great repair.
the power meters is called flying spot when only 1 or 2 led's light up and yes it is cool
I like it.
@@12voltvids yes very cool gives it a more professional look
Your skill sir, really is something to be jealous of.......I envy you.
I can build a engine and install it in a car blindfolded but when it comes to this kind of work specially soldering and finding whats wrong in a sea of little transistors and capacitors i take my hat off to these guys,i couldn't solder 2 pieces together if my life depended on it and hes doing it sideways,lol
Nice receiver
Might be worth soldering a Bidirectional TVS Diode externally across the switch. Essentially a zener diode made for AC that clamps the positive or negative voltage spike when the contacts separate. Should drastically reduce the arcing and extend the life of the already worn contacts.
Good idea, i am trying to tackle a problem where the customer is complaining about a ‘click sound’ in the speaker when he switches it off, i’ve increased the cap over the switch but can really get rid of it.
Which one would you use? 1,5ke250ca or 300ca (230V country)
@@martijnappeldoorn8686 You might be better off with a relay that disconnects the speakers as soon as the AC voltage cuts out; there are ready made PCBs on ebay that do just that, using an additional 12V transformer in parallel with the main one.
@@paulb4661 that is already present Paul, if i increase the cap to circa 1uF it ‘s gone , but then the amp doesn’t switch off completly so i think i will try a tvs diode see if that helps
Actually I like the headlight that has the LED that wraps all the way around the front of your head. Those work great. You don't have to adjust anything.
Don't have to adjust anything on this either. Just turn head lol.
The one I'm talking about you don't even have to turn your head. Only problem is if there's somebody in the room with you it would bother the hell out of them.
@@frankc1430 that sounds like a you problem.
I have a Realistic STA-2270, 65 watt per channel, and after repairing the power switch the second time, because it had welded together, I decided to avoid a third repair. It is a pain to get to. The switches for that are also non-existent. I re-wired it to use a relay as the power switch so now the power switch only has to handle the current from the relay coil, much less than it was handling. So far so good. The only thing I sort of goofed on was I used the wrong side of the relay so the on/off position of the switch is the opposite of what it was.
If you used the NC instead of the NO relay contacts it might be worth fixing. You'd be wasting power whenever the unit is turned off and if there are power glitches it will power on unnecessarily.
@@eDoc2020 You are right and I have thought of rewiring it just that way. Just haven't gotten to it yet and so far it is working without issue.
I was just wondering is it possible to swap out the power switch with one of the lesser used switches? I thoroughly enjoy your videos. Keep up the great work !
No different type of switch.
I like that this has the power transistors rather than those Darlington packs...I think that's what you call em right? I have an SA200 that I bought in 79 that I have not had to open yet and use everyday almost. I use the preamp mainly for archiving vinyl digitally for customers the last 20 years. A great workhorse! One reason mine is still going on without a hitch is because I always keep it on.....never gets shut off.
You mean IPM, integrated power module.
if you take the aluminum face plate off of this you most likely wont be able to get it to go back on. there are plastic inserts that fit around all the knob controls - you have to use an 11mm deep socket to remove the plastic inserts. they look like a thimble that would fit over your thumb. then the cover will go on. then put the sockets into the face of the unit and use the 11mm nuts to hold them in place. hand tighten the nuts. push the knobs back on . this will throw you for a loop
Would you go as far as asking the owner if they would consider fitting a soft start circuit? That would certainly stop the on/off switch from burning up from inrush current.
That is a beautiful unit. Btw, what kind of tuning is that? It doesn't look like the usual capacitor type tuning. Inductor?
It just a capacitor.
Would you mind telling me what the song is at 20:51? It's really nice...
I personally like the 'christmas lights in series' much more than LED lights. I'm not a fan of LED light frequency it emits. :) Thanks for showing your method of installing them.
I agree, incandescent looks better. I use incandescent in my giant lit grandfather clock. They are on a dimmer so they last forever and are long filament tubular lamps the light the pendulum cabinet. It's a 20,000.00 clock that i inherited.
@@12voltvids WOW you should show that puppy off.. I do respect a nice clock !!!
@@SPINNINGMYWHEELS777
It is a very limited edition made by rideway. The woman that bought it when it was new paid 16,000.000 it as a special order. It's part of the Biltmore collection to represent each state room in the Biltmore mansion. The mansion has 250 rooms and they built one clock to represent each one. The one i have is 021 out if 250 made. That makes it rare. It is huge. Will not fit in rooms with 8' ceiling as it is about 8' 4" base to top. Hand crafted and the pendulum base it lot up. Younger generation don't appreciate these massive clocks. My son thinks i should sell it. I laughed. Prices go up and down on these but one thing for sure they all all go up in value as they get older. Since mine is a very limited run it should increase much faster then a regular production run. What makes this one special, besides the serial plate is the size. About 6" taller than the regular clocks which come in a little under 8' so they fit in normal 8' ceiling rooms.
@@12voltvids amazing!! I bet it's stunning and a work of art.
Does anyone know who made Realistic stereo receivers? Was it their own product? I remember having to replace the stereo indicator bulb located on the tuner pointer. I had to paint that red to match the original. This receiver surprisingly out performed others that I owned.
The way capacitor testers read capacitance, they use the time it takes to charge to a certain voltage to calculate capacitance. Contrary to what many people believe, capacitors that read over their rated capacitance are more likely to have developed internal shorting and are going bad. When a capacitor has internal shorting, the indicated value by the tester won't be accurate and is likely to be much lower than indicated. An 18 year old electrolytic that reads above it's rated uf is likely going bad.
This is why ESR is a more accurate read as it measures the equivalent series resistance using ac voltage and current when capacitors dry up the ESR will tend to climb. Measuring the microfarad however also gives you a good indication of where the capacitor is most electrolytics are 20% tolerance at a minimum. so a 100 microfarad capacitor will typically measure anywhere between about 90 and 120 so that range you're in good shape if you are measuring a 100 micro farad capacitor and it was showing 400 microfarads then you've got a serious issue with it. What I found however is the opposite if the cap has got an internal short it measures low so that 100 microfarad capacitor might be measuring 68. I think different meters work on different principles and some do a better job than others. I had a capacitor go dead short once that one was tricky because you put the ESR meter on it and it's showing like 0.01 which look to be very good or 0.03 or whatever but it looked to be very good however put the capacitor meter on it and it showed low but the ohm meter on it it's showed short. I have found however that vintage cap from the late '70s and into the early '80s generally tend to last a long time. The reason for that is a lot of them used PCB oil which was very stable. Toxic but stable, and these caps generally tended to last an extremely long time unless they were physically damaged. By physically damaged I mean the leaves manhandled when they were being installed or the top squeeze with the pair of pliers or something when it was being installed or someone working on it bending parts back and forth to get access to another component that can break the seal and allow the electrolytic to escape. Cops made after the mid 80s and well into the 90s however were horrible they changed the formulation to make them environmentally friendly and in the process made them extremely unreliable. They also went to a water based electrolytic which as you know water boils at 100 Celsius. So even getting close to the boiling point pressure starts to build inside them if you go over their rating voltage or too high in frequency the water will boil and it will blow the safety vent. No I'm not saying old caps don't fail they certainly do it's just that their failure rate is much lower than the mid 80s to late 90s which were a very bad time to be an electrolytic capacitor
@@12voltvids Thanks for information. Yes you are right about electrolytic caps. Sorry my bad. I was thinking of those small non-electrolytic caps used in old vintage tube gear that develop DC resistance (not ESR). Most of the time when measuring the value for a electrically leaky paper or film cap it is over value on any of my capacitance meters. Of course if it has a dead short it won't read much/any capacitance at all
@@multicyclist yeah the paper caps used in tube gear they all have to be replaced no matter how they test. Even if you use a high voltage breakdown tester which is really the only way to test them which is a tester that applies 500 or 600 volts to the capacitor and measures for any DC leakage even testing them that way they can test good today and tomorrow develop leakage. Because vacuum tubes are high impedance devices it takes very little leakage to pull a tube into over conducting which will red plate it and damage the tube and damage any other components that may be in that circuit like transformers. When I see vacuum tube gear I don't even check the Caps I just change them. I collect vintage radios and everyone that I've got I've changed out all the caps in the coupling circuits and don't even bother testing them. The problem with the paper caps is acid in the paper when it was made during the bleaching operation causes the paper to eventually become conductive.
Considering that the power switch had a lot of damage from arcing, maybe it would have been worth swapping the cap that is across the power switch, it may have went down in value.
Generally these numbers don't go down in value usually when they fail they just short and then it won't turn off at all.
Christmas lights Technics
I'm not a fan of the LED power meters. Give me an old-fashioned analog meter any day.
I prefer to use Deoxit contact cleaner. It's a little pricey but it works very well. Not to mention it also lubricates.
This is 40 year old nutrol with freon tf solvent. It is superrior to the new stuff. I have deoxit as well but i am pissed at the company for disqualifying me from the last contest because they determined that multiple people were using vpn to vote for me and the guy in second place. So why would i promote them. I say fuck em, I can't control what others do.
As always remove the pots and switches, disassemble them, cleaning with a fibre brush, apply contact grease and there we go for the next 10+ years. Everything else is mumpitz. OK, I also would put a new Power switch in if contacts are burned. Of course, It is all a matter of time and what a Customer is willing to pay for. I do restore Profi Studio Equipment and People see it also as an asset. I love your Workshop BTW. This is a place where someone works and it is alive. Greetings from Devon.
@@telegraphhill803 removing the switches runs the real risk that the plastic will shatter. Good contact cleaner with lubricant works very well. Unfortunately the modern environmentally friendly cleaners are nothing compared to the old cleaners (I have 40 years old cans of cleaner when the good stuff was still made). Nutrol used to me the best. It was devoloped by the Telecom industry for cleaning stroger and crossbar switches and keep them clean. Chemtronix tun-o-power was another excellent cleaner with. Very fine grit that would polish switch contacts. They has pumice (volcanic ash) in it.
To bad you didn’t catch that bad switches right away but if you didn’t change those capacitors it would have probably been trouble down the road. Great repair! I started repair on a Marantz PMD 200 last night, oh my trying to get in to change the belts is a nightmare which you probably already know.
Curious what the original bulbs would have looked like, were they just painted or some interesting metallic coating inside? Apparently the pinball guys use "Dip Coating Bulb Paint" or "Bulb Dipping Paint"
You can dip them in a tinted laquor. Pale green would have been the original color.I highly doubt the owner will even know what the original looked like because it is highly unlikely he ever saw this unit in operation.
I had a question, i have a Technics unit but its modern, it has A and B speakers and on the B side the left one has this issue where it will quit working and if you wiggle it it comes back on then it goes out again etc,doesn't take much to make it go out, what could that be and ball park figure how much would it cost to fix? its a nice unit, id like to keep it, i took the top cover off once but those banks of speakers are buried and i didn't see anything that stood out as being loose or nothing, thank you for your time.
Sounds like a connection problem to me.
What cooling fan to use in the Technics SAEX310 in place of the original fan, as I'm not able to get it.
No idea
Who needs sound as long as it looks good! 🤣On the serious side, perhaps there's a sensitivity switch for the power meters 🤔
There is.
👍👍😊😊👌👌
dollar store enamel paint (For nails) works very well if you like to match the bulb color - once it dries it's on good. just don't use an opaque color LOL
Hoping you can help- restoring an SA700 and someone has previously run a 47uf cap (on the back of the pcb no less) from the bottom leg of C450 (normally unused) over to R205. Can you tell me what this was intending to accomplish? Thanks so much in advance.
They bridged the cap over. Probably because the seevicer didnt have yhe exact replacement or one they had wouldn't fit. Very common repair procedure. Used to see that done all the time when stuff came in that had been previously serviced. Very often done on the large multi stage chaasis caps. May have 4 caps inside and 1 went bad so yhe tech wpuld cit off the bad lug and stick an external. I have done that on omd tube radios.
Amazing answer and thanks for the quick response. If I'm doing a full recap, would you recommend just replacing the (very old) cap in the exact same fashion? Or should the problem be resolved with all new electrolytics? Thanks again for the information and fantastic video!
@@marshallsanchez2070 if you are changing them all just install them the way they originally were. You will notice a difference in sound. If you are used to the sound that it produces now you may or may not be happy with the new sound as it will sound different. This is primarily due to the difference in chemestey of the electrolytic between old oil based caps and new water based caps. Even if they have the same value they have different charistics which will change the "color" of the sound. Some like it, others hate it. I had a guy pay me a second time to put all the old caps (that he took away) afyey I did a full recap a number of years ago. He didn't like the new sound. Said it was harsh.
Perfect. That’s fantastic information. I really appreciate your help. Thank you.
I do have *one* more question that I ask because I've never really gotten a straight answer from anyone else... Is there any trick to accessing the bottom of the 15k power caps? The only thing I've seen is someone suggesting drilling holes in the plate thats covering them. Is that your recommendation as well? Thanks again.@@12voltvids
Matsushita caps. purpleish looking color.
Which spray cleaner do you use? I used wd40 and it made it worse 😢
I had Marantz look like this
Please which area u
I have Arcom 280av Receiver can I Replace 63v 15000uf (4caps) Capacitors instead of 12000uf (4caps).
As long as the voltage rating is at least as high as the original no problem.
@@12voltvids Thank you♥️
Hi Dave, I sometimes use a fine point marker, yellow color and mark a dot on the circuit board, if I can reach it with the marker and mark the minus side of the capacitors on the board, maybe that would be helpful for you ,great video!
I remember how them come out as I am replacing them one at a time
@@12voltvids Yeah, unfortunately sometimes I forget, so I use a marker, anyway, I miss the vintage stereo equipment, easier to work on!
You changed the caps all were close to spec and it now works but didn't before ,very critical values then .
Someone's been using the fast forward button haven't they? The reason it didn't work had nothing to do with the caps. The reason it didn't work was because the tape monitor switch was so badly oxidated that no signal was making through it even when I flipped it a few times at the beginning no signal was making it through it. I got thrown off track initially because the green light that says safety I was thinking that that was an indicator that it was in a fault mode but that's actually not the case that light comes on when it's working it goes out if it's in protection, and the fact that none of the dial lights were lighting up I was thinking power supply issue but the dilates were lighting up because they were all burned out. I changed all the caps still had no sound and it just happened to as it was firing up one time off camera I heard a little bit of sound come out of one of the speakers momentarily. I then started flipping the switches back and forth and heard a little scratch on the switch and then realized the problem was actually the switch itself both the record out switch and the tape monitor switch we're a really bad shape and it took a lot of cleaning to get them to actually perform properly. The volume control is also scratchy but the other controls were all fine as were all the other switches with the exception of the power switch
Sorry me,I watched it through all the intermittent issues with the switches and main on off but missed your diagnosis some how I tend to see all the way through real time as your such a good host.
People will pay out the nose for these old Technics in online auctions. I say let them have them. Even back in the late 70's when they were new you had to tune them up every year or suffer from the dirty switch and knob problems.
There is a sucker born every minute. I get them for free
get the right bulbs
Ohhhhhhhh, how I hate with a passion seeing those purple capacitors.
소리가 별로임. Fisher tube receiver is best..
I have an old MacIntosh 1600 tube receiver. A few levels above your Fisher
Those technics are cool ,but every one I've come across has had really bad switches and you really have to work the switches to clean them
This one aparantly has not seen power since the mid 80s. Was replaced with a surround system and forgotten about.
Appears FrankFurter C. Is the comments critic! But FrankFurter C. has a channel with ZERO content! Time for Frankie Boy to do a tear down. repair, and re-assemble video!
You found the troll. Well one of them.... 😃
Which spray cleaner do you use? I used wd40 and it made it worse 😢