I like that fact that your videos are always clear! - no silly wavering the camera about. That Sony is quite sophisticated, often leading to sophisticated problems. Conceptually, I like the idea of auto-reverse, but from a practical and calibration point of view - I don't think it's worth it, especially if a head has to rotate. Kind wishes, James.
Couldn't find my fine-nosed cutters, and had a pair of tiny scissors with really fine tips, in the tool box. The scissors worked perfectly, and I made a mental note to mention it to you...while they wouldn't cut through epoxy, they'll let you get up really, really close on a wire end.
Hello! I inherited a 440 that was all gummed up. After cleaning, the play feature never worked. After watching this video, I discovered that I had bulging caps! Thanks!!!
Great video! I´m working on several Sony TC´s for the moment. Yesterday when I was testing a TC-366 by playing a tape for several hours, suddenly there was a smell and smoke came out from the unit. After removal of the backplate, I noticed that the motor was very hot, and I thought that the motor was toast. After watching your video, I checked the encapsulated component in my unit, and guess what, it had partially melted! It is marked in the schematics as CP301 (0,033uF+120ohm). There is also another similar component somewhere called CP302 (0,1uF+120ohm), but that one I haven´t found yet. The machine still seems to work as normal.
Those are snubbers and the caps fail eventually. They are to cancel out any HV spikes from solenoids to keep switch and relay contacts from burning up. (Used on reversing motors too) you can replace them with just a capacitor and resistor in series as shown in the schematic
Oh the days of the reel to reel machines. Anyway, you jogged my memory of resistors, capacitors and transistors, too. How you put that giant capacitor in there connected to a resistor was something. I assume that capacitor is a stronger one than the one that was in it. Great repair! Your intelligence behooves me. The Oscilloscope is the one I'll have to learn all over again. The settings on it...That's another whole ball game. You also have persistence in finding the problem. You have a sense of what is wrong with a unit.
When they fail they turn into resistors and will stop the ac motor from spinning. In the case of the one across the power switch, when it goes bad the motor will turn very slowly when it is supposed to be stopped.
I was curious you had done work on an akai that had a head that went up and down to change directions and you hadve the type of head change with a toothed gear and motor to change it I could be wrong which do you think is a better design as far as length of life for function time these videos you do are a real life saver and I really enjoy your comments and how things work together with each other and it is great that there are some genuine people here that know their stuff and do it very well. all the best keep up the great job
Nice repair. Yeah, those electrician scissors are very sharp. When I used to be a phone installer we had those, and you could cut a penny in half with them.
Easily cut a penny in half with them when pennies were made out of copper. Later ones here were made out of nickle or steel and copper plated. That made them a little more difficult to cut.
Nice vid. I have a TC440. Only things I have replaced on mine are the belt and starter cap. The blown RC components are actually snubber circuits to control the back EMF. When I worked at KSC, we had our old hydraulic cart that we were letting Thiokol 'borrow'. It had been sitting in a warehouse that wasn't climate controlled for like 7 or 8 years. I was the engineering test conductor for this. We fired it up and started testing the solenoid controlled valves, each of which had a potted snubber circuit like in the TC440. Everytime we activated a valve we let the smoke out of the corresponding snubber. After having my tech gin up a new RC snubber 3 or 4 times, I said screw it and stopped testing and had my tech make new snubbers and replace all of them (about 60 in all, IIRC.) He wasn't too happy and the higher ups weren't crazy about the delay, but that was life at the Rocket Ranch.
The RC devices you replaced are likely to outlast everything else, not being potted may help them to stay cooler and last. That classic voltage regulator is fed from a transformer and it's primary goes to the servo chip, some jiggery pokery going on there lol :-D. Servo just reminds me of pll circuits, old disk drive servos, and washing machine motor feedback speed control. Servos can be a pain in old piano key jvc video recorders, "breathing picture".
"The RC devices you replaced are likely to outlast everything else". Not likely, as they seem like metallized paper caps inside. Have you seen Wima and Rifa MP series EMI filter capacitors failing (the ones in translucent encapsulation)? I have seen, dozens of them. And they are still produced today for some mysterious reason...
@@devicemodder Yeah I tested out the theory of the lineman's one day telling another tech. I'm about to cut this 240V line to test their 600V rating, after having turned the breaker off earlier. Turned out the joke was on me because I didn't know he had turned it back on for some reason & KABOOM!!!!!! Well they definitely did their job very well, not even a little buzz. Although it did take out a little chunk of metal with, but I still use them till this day.
That was really interesting. I have an old reel to reel where the motors only turned really slowly. I never got around. To troubleshoot it, but I think I’ll have a go at it soon. Thanks for sharing
Had so much fun with my dads Sony recording using 2 microphones 35 year ago even when it stopped working I remember pulling apart, I stripped it down. I think now oh why
Had a buddy in high school who lived 1/4 mile down the road from a local low power AM tower. I remember calling him on his landline telephone, and hearing the station faintly in the background. I guess they would experience the same deal with all the electronics at the house. The thing we got the most amusement out of was receiving the station via toaster oven. Just open the glass door, and it would come out nice and clear.
Many decades ago a friend of mine lived near a radio transmitter. As Dave says, EVERYTHING electronic and electric in that house picked up radio. As you say, we could literally listen to the radio on his toaster. Interesting to visit, but I imagine it would be hell to live with.
The station I mentioned (WESX) is currently listed at a measly 450W. The station format, ownership, and broadcast tower location have all long since changed. But it wouldn’t surprise me if it may be the same power they were using with the old tower. Just a local yokel station, with the original tower built in the late 30’s, right next to the Atlantic Ocean. It was just enough power to push moldy oldies, car talk, local news, and polka Sundays, to half a dozen different towns, and at least one Black & Decker toaster nearby.
@@erikj.2066 We used to have a bunch of low power AM stations. Paul Carlson (mrcarlsonslab) has the old transmitter out of the radio station from Hope BC. He converted it to 160 meters AM for HAM radio use.I hand built low power FM transmitters right out of high school that were installed in small communities to relay FM from other towns into small interior towns. Was working for a small electronics manufacturing firm that mainly made CATV amplifiers and modulators. They made fixed frequency modulators and receivers for the CATV industry. Back then all the cable companies would receive distant FM stations and re-modulate them onto the cable system. I remember hand building the power amplifiers for the transmitter. Based on the Motorola MRF317 RF amplifier, that could run 100 watts all day and barely break a sweat. We were limiting them to I think it was 40 watts as that was more than enough power to cover the installation. A 100 watt FM transmitter would fit in a box about the size of a CD player. I am sure some of those hand built amp boards are still on the air. As a junior tech my job was to solder all the components onto the board and build the enclosure, mount everything. Then it went to the alignment lab where an engineer would put it on the spectrum analyzer and tune it to the desired frequency. It was a summer job when I was 18. I think they paid me 5 bucks an hour at the time when minimum wage was 3.15. Once that project was done I was laid off as that was what companies did. Hire a tech for a project then when project was done, you were done too. That was the same when i worked for Sony in 83. Temp tech job to modify hundreds of brand new Betamax VCRs. Rewind kits, and capacitor rework jobs on brand new machines that were en-route to the stores, fresh off the boat from Tokyo.
Used to happen a lot with the folks who lived in the villages under the Rampisham SW transmitter station, Dorset, UK, remote central locking on cars would not work and Russian radio would come out through their toasters! Not surprising really given the fact that Rampisham had multiple MW's of transmitter power and an impressive multitude of curtain arrays to match. Always a spectacular landmark, esp. when everywhere else is just farms for miles. tx.mb21.co.uk/gallery/gallerypage.php?txid=1662&pageid=2481 Due to BBC Word service and other broadcasters budget cuts it's all but gone now and only a couple of the supporting towers remain (with other equipment on them inc. a low power TV relay). The site is up for sale if anyone wanted it although afaik it's been gutted, I'm guessing both for scrap value and parts for other transmitters still operating.
Following your video....I got my machine working almost. The left reel I cannot get to turn in play mode. Right side play works. It even records on the right...but the wheels not turning affects the recording. Do you service machines ? Being as you gotnthis model working...you seem to be the guy for the job.
Akai did use the combo resistor+capacitor on their earlier models such as the first solid state models (X-355, etc.) They went to separate parts after 1968. This was apparently due to failures with the combos and complaints from service shops.
All the Akai units I have serviced, which is not many, just the 3 I own have separate components. As you summed it up. High failure rates. I remember these going bad on the Sony units I worked on, and always did what I did here, made my own parts.
Those arc snubbers in Sony and Akai decks were always so problematic and would usually short when they fail, thereby jumping out the switch contacts they were protecting. In an auto-reverse machine this usually means the motor is trying to go in both directions at once since both switches are closed, causing the the stall mode in the motor. TEAC decks never seem to have this failure, the worst I’ve seen on those is the old Suzuki oil cap arc snubbers exploding on the old 4010 era decks.😅
Dave, did I see that this machine “flips” the heads for the reverse play back. If so, how do they keep the heads tracking properly time after time of use.
Yes the head flips around. This is one of those "dumb" Sony designs. Love how they say on the front "six head function"! Really, I count 4. 2 erase, and a record and play head that flips around. Akai did it right with the deck I have, the GX265. 6 heads, all glass. 1 center mounted capstan / pinch roller. 3 heads for each direction.
Yes, and mine (tc440) stops rotating after it sits a while. I have to physically rotate it by hand a few times to break it loose. Any suggestions on lube to free it up?
@@lindsaythomas2283 Well it depends on what is gummed up. Could be the capstan or the main motor. The main motor has an oil fill tube that will take oil into the motor bearing. A few drops a year is all that is needed. Don't put too much in, that is worse than not enough. Always use non detergent electric motor oil, not engine oil. Engine oil has detergents and polymers in it to trap combustion blow by, and it will gum up electric motors and other precision bearings. Personally I use 3 in 1 electric motor oil. It is a very good 20wt non detergent petroleum oil. I use it on everything including clock mechanisms. If you can oil a clock and it is still running 10 years later with no ill effects then you know that it is good oil.
Great investigation. Well documented. Great repair! Like those stubby scissors - where does one get them? Looking at that schematic diag. I noticed another of those cap/res components (CP402) across a switch S401 What is the purpose of this use? Thanks for your excellent description of the phase-shift requirement for induction motor. Talking about the induced AM transmission into the fabic of the farm house - I knew someone in N.Van who lived under a power line - he used to light his house using old non-working fluorescent tubes induced by the over-head power lines!
The cp device job is to dampen the inductive kick from the motor when a switch opens. To prevent pitting of the switch. Think of it like a shock absorber. Called a snubbed circuit in technical terms. A capacitor would do the same thing or a diode in a dc circuit as is always seen placed across the coil in relays or solenoids. The series resistor is to protect in the event of the capacitor shorting as it did here. When the cap shorts without the resistor it would be a dead short. This would overload other components such as the run capacitor. When it shorts as it did here it becomes a resistor and basically nullifies the phase shift from the capacitor and the motor stops. When I put in the first pair pulled from the scrap board they failed right away probably because they were already on the way out. The only time they see any activity is when the motor turns off or changes direction and it is just a big spike of voltage. The electrician scissors are made by Klein, but Miller also make them. You can buy them at home depot.
Good video! I have the akai GX365 . Instead of the heads flipping around, it has a plunger solenoid that that moves the heads up and down for auto reverse. The manual says it uses a hysteresis synchronous 3 speed motor (2-4-8 poles) . The more poles the slower the speed? I opened it up once and its relay city inside.
The cap/resistor has nothing to do with wow and flutter. The pinch rollers affect that more than anything. The cap/resistor that failed is part of the proection circuit that protects the switches from induction arcing created by switching the motor on and off, or changing the direction. The snubber circuit. The There is normally no current flowing through it. If there is then there is a problem somewhere else. That is why I put the meter across it. 2 of them failed, and when I swapped them out for 2 used ones they also failed. I have to sum this up to the old parts on the scrap board I pulled were likely also bad, just hadn't puffed up until voltage applied. I could remove them completely and the unit would run just fine, and some techs did just that as the motor will run just fine, but sparks created in the switches will cause an audible pop in the sound when the switch activates, and it will eventually pit the contacts on the switch.
Components CP403 through CP407 are snubber networks. Their purpose is to suppress any arc that may occur in the switch. CP403 and CP404 protect S403, CP405 and CP406 protect S402, and CP407 protects S404. The snubber networks play no part in either the direction or the speed of the motor. Snubber networks like that are still in wide use today, even protecting solid-state switches. They are readily available from commodity parts vendors (DigiKey, Mouser, et.al.) They are not anything custom that Sony cooked up. They are widely used in many places. The capacitors in them are much too small to affect the phase-shift that makes the motor turn. As noted, it is C406 that generates the phase shift in the lower winding of the motor M. C604 is a large metalized paper capacitor that physically resembles a modern electrolytic. But it is made for motor start/run applications. Many of them are failing now decades later. Fortunately, replacement polypropylene metallized film capacitors are readily available at sensible prices. S404 switches between providing full mains voltage (117VAC) to the motor for FF/REW spooling vs. turning the flywheel/capstan at the selected tape speed (via 90VAC modulated by Q501 and the servo circuit). This was a common servo circuit used in many models of Sony reel-to-reel machines of that era. You can easily change the speed of the motor by changing a single resistance value in the servo circuit. In the TC 440 this is done with switch S501-1 and resistors R501 through R506 R501, R503 and R505 are screwdriver adjust pots which calibrate the three tape speeds. That IC used in the servo circuit (CX-032) is the magic part that you can't buy just anywhere. There appear to be still some sources at premium prices. Everything else in the motor and servo circuit appear to be replacable by commodity components. Of course the rubber components (belts, pinch rollers, idler wheels, etc) are critical. If replacement sources of them disappear one day, these vingage machines will be scrap metal. I have a Sony TC-850 and a TC-654 Those things really were mechanical marvels. Things are so much simpler and easier here in the digital era. :-) Loved the video. Brings back memories of working on those things back in the day.
Right but when the capacitor shorts, it becomes a resistor and that will cancel out the phase shift from the motor run capacitor causing a loss of torque in the motor. The CX-032 is a custom Sony chip, that regulates the motor speed. The motor speed is set by changing the voltage at pin 3 of the cx032. That voltage is referenced from pin 5 going through resistor divider and speed control VR network. One could put a variable resistor between pin 3 and 5 and have a fully variable speed. I would imagine these chips are getting pretty hard to find today, and nothing else is available as a replacement. I replaced literally hundreds of these cap/resistor networks in the snubber when I worked on these machines back in the early 80's Saw tons of them when I first got into the service business, but haven't worked on many since the mid 90's. The majority retired these old R2R machines, and I saw literally none for many years, untill I worked on these few over the past year and 6 of those are mine.
Motor won't cause this. Loss of phase shifted winding will. So capacitor is the likely culprit. In this case the cap in the snubber shorted and turned it into a resistor which effectively canceled out the phase shift. The unit will actually operate without those parts BTW. They are protection circuits to protect the switches from pitting when they are turned on and off from arcing.
No C406 is the phase shift capacitor for the AC motor. The other components are protection components to protect the switches from induction kick back.
I have a Sony tc440 just brought have same problem you fixed in your video, l didn’t get the size of the compascitator and resistor used in duplication of the original one. Can you send a reply.
I've got an old Sony TC440 that I got brand new back in the early 70's from a friend who was stationed in Japan. It needs worked on similar to what you did to this one. I can ship from Akron, Ohio. Can you work on it? Thanks
The barn door to the transmitter shack had a warning sign about high rf levels on it and the new site on the other side of the highway also has a farm house on it but a big metal gate across the driveway with the rf warning sign on it. Now the transmitter building has 2 50kw am stations in it. 1040 and 1410 and 7 towers out back in the field.
@@12voltvids Many radio and TV stations in Portland Oregon have their towers in the west hills of the city. Because of the spectacular views, there are very expensive neighborhoods in the same areas. There is also a high cancer rate in those neighborhoods, particularly among women who can afford to stay home during the day.
@@BlankBrain I don't think there is any denying that there is risk with exposure to high RF radiation. At work when we work on poles that have cellular antennas on them we have to power them down before going up. Most have a switch located about half way up the pole so we can power the unit off before going up to work, and these cell antennas I am talking about are only 4 watts. Imagine constant exposure to high power UHF t transmitters pumping out a couple hundred thousand watts of ERP. I remember when channel 21 went on the air here in the gulf islands before they moved to channel 10 back in the analog days. At the sign off every night they would announce their transmitter power. See the sign off for UHF and VHF here: 1234 KW on UHF VHF 325KW visual 65KW aural UHF - ua-cam.com/video/h_Svj19-qpY/v-deo.html VHF - ua-cam.com/video/-7zp7Y09xMQ/v-deo.html That's a shitload of power. Wouldn't want to live anywhere near that transmitter.
Are you aware of a mod that includes adding a board to a reel to reel? I have an old tascam 22-2 with an extra board that is connected to the play back head and has a multi pin connector that i wonder is for? There also evidence of jumped pins on the the decks boards. I migh thave ran this by you before... uhave a email I could send you a couple of pics?
I am aware that some have added a direct play head output so they can run low level to an external preamp. Some people prefer to use a tube preamp as opposed to the solid state in most recorders because they consider the internal preamp inferior.
I have two Sony TC-580 reel to reel l brought for repair. Sad to say they both have the same problem. Will play when torque resisters are cold, but reels slow down and stop when resistors get warm. These resistors controll ffw and revw torque,# rwh30j150-m and rwh20j1k-m. Any suggestions on how to fix?
About you am transmitter, I hope the antenna isn't connected to the ground. AM transmitting station always Isolate their guyed mast from the ground which makes them very fragile on some weather conditions
My am transmitter just is connected to a 9 foot piece of wire suspended from the ceiling. The station I visited has towers mounted on insulators mounted on raised platforms.
Yes the magic of AM radio, it’s even possible to listen to a station without using a battery or be connected to grid (the old way, crystal receivers that also were used on ships in the beginning of previous century)
27:23 Oooh, no... Fake Rukycon (ruKycon, watch closely) capacitors.... No wonder the hybrid RC blocks failed: for me the capacitor inside looks like metallized paper. Should have replaced all of them with PP or PE, as they go unreliable after 15-20 years, and this unit is much older than that. Just like the RIFA and WIMA MP series EMI filter capacitors in translucent encapsulation. They are garbage, blowing up in everything, and they are still produced today. I really don't understand why these otherwise reputable manufacturers do this, as their 'explosive nature' is well known in the industry for at least 20-30 years now. I don't know how these parts comply with X2 and especially Y2 safety regulations, as I've seen PCBs with holes burnt in them by these MP series firecrackers.
My bench is clean compared to many i have seen in working repair shops. Poke your head in the back of a busy shop and see how it looks. Units ripped apart all over the place. Seriously. Sure there were some slow places where the guy had time to clean up between repairs because there was no work. The last year i was at the shop the place was spotless because there was no work but in a busy shop there is no time to clean up after every job. I clean my bench when i have nothing to do which is never because when I am not working on something I am nowhere around the shop. I spend as little time as possible in the shop. Seriously though go look in a busy shop and you will see it looks exactly the same. Back in my repair days we hired a guy that was very particular. He put every tool in a specific place and had an outline around it on the punch board wall where he hung every tool. He was very anal about sweeping his bench after every job. He did about 1/4 the work I and the other tech did. The boss noted this and gave him an ultimatum. Increase his productivity or look for another job. He quit. Time is money, and sweeping the floor and bench doesn't bring in any money.
@@georgemkirko9645 No offense taken. Just stating the facts. The best shops i have worked for or worked in always looked like a bomb went off inside because the techs are busy making money. We all have the same attitude. I am an engineer not a janitor. Want the shop clean, hire a janitor to clean the floor. I remember my first day at the phone company. I was checking the oil on my truck. One of the old guys came up to me and said. "Mechanics don't fix phones and phone men don't fix trucks! Put that dipstick away!"
@@12voltvids I would disagree on this... Those days long gone.... In our current world the most appropriate statement is - if you want it done right than do it yourself...
@@georgemkirko9645 There are still a few shops around. I have been in 1 recently and it looked like the shop i worked at. Plenty of units in various state of disassembly all over the place, some having parts picked off them. There aren't as many shops around but a few still exist.
The owner of it is more than capable of changing the belt. That is if the belt is available. Many of those are very hard if not impossible to find. Try to find a belt for a 3/4" vtr.
I like that fact that your videos are always clear! - no silly wavering the camera about.
That Sony is quite sophisticated, often leading to sophisticated problems. Conceptually, I like the idea of auto-reverse, but from a practical and calibration point of view - I don't think it's worth it, especially if a head has to rotate.
Kind wishes,
James.
Couldn't find my fine-nosed cutters, and had a pair of tiny scissors with really fine tips, in the tool box. The scissors worked perfectly, and I made a mental note to mention it to you...while they wouldn't cut through epoxy, they'll let you get up really, really close on a wire end.
Hello! I inherited a 440 that was all gummed up. After cleaning, the play feature never worked. After watching this video, I discovered that I had bulging caps! Thanks!!!
I can smell your workshop just from the gear you are working on.
I watched the first one, in which had the death wobble
That is pretty cool how the head rotates
This another great video with great troubleshooting
Rotating heads is a bad idea. Much better design was akai with 6 heads. 3 for each direction and a center mounted capstan shaft.
Great video!
I´m working on several Sony TC´s for the moment. Yesterday when I was testing a TC-366 by playing a tape for several hours, suddenly there was a smell and smoke came out from the unit. After removal of the backplate, I noticed that the motor was very hot, and I thought that the motor was toast. After watching your video, I checked the encapsulated component in my unit, and guess what, it had partially melted!
It is marked in the schematics as CP301 (0,033uF+120ohm). There is also another similar component somewhere called CP302 (0,1uF+120ohm), but that one I haven´t found yet.
The machine still seems to work as normal.
Those are snubbers and the caps fail eventually. They are to cancel out any HV spikes from solenoids to keep switch and relay contacts from burning up. (Used on reversing motors too) you can replace them with just a capacitor and resistor in series as shown in the schematic
@@12voltvids Thanks for the reply. I have just placed an order of new components and will later replace these on all units I´m having.
Oh the days of the reel to reel machines. Anyway, you jogged my memory of resistors, capacitors and transistors, too. How you put that giant capacitor in there connected to a resistor was something. I assume that capacitor is a stronger one than the one that was in it. Great repair! Your intelligence behooves me. The Oscilloscope is the one I'll have to learn all over again. The settings on it...That's another whole ball game. You also have persistence in finding the problem. You have a sense of what is wrong with a unit.
The original part rated 500v the replacement 630 so it should never fail again.
Great video, I have a Sony TC730 which has the same orange Caps in it and has a similar issue. Will look into it now, when I have some spare time.
When they fail they turn into resistors and will stop the ac motor from spinning. In the case of the one across the power switch, when it goes bad the motor will turn very slowly when it is supposed to be stopped.
Great video. I just bought this model for $10.
I was curious you had done work on an akai that had a head that went up and down to change directions and you hadve the type of head change with a toothed gear and motor to change it I could be wrong which do you think is a better design as far as length of life for function time these videos you do are a real life saver and I really enjoy your comments and how things work together with each other and it is great that there are some genuine people here that know their stuff and do it very well. all the best keep up the great job
What a fanfare at the end. E.L.P. That was a fun job.
Great video, watched it twice, luv the drawings of different phases. keep up the good work. Kind Regards Christopher U.K.
Sony no bologna...lol..
That is a nice unit...good job..you are the master..cheers 🍻🇺🇸🇺🇸
Nice repair. Yeah, those electrician scissors are very sharp. When I used to be a phone installer we had those, and you could cut a penny in half with them.
Easily cut a penny in half with them when pennies were made out of copper. Later ones here were made out of nickle or steel and copper plated. That made them a little more difficult to cut.
Looks nice. Glad you can repair it.
Nice vid. I have a TC440. Only things I have replaced on mine are the belt and starter cap. The blown RC components are actually snubber circuits to control the back EMF. When I worked at KSC, we had our old hydraulic cart that we were letting Thiokol 'borrow'. It had been sitting in a warehouse that wasn't climate controlled for like 7 or 8 years. I was the engineering test conductor for this. We fired it up and started testing the solenoid controlled valves, each of which had a potted snubber circuit like in the TC440. Everytime we activated a valve we let the smoke out of the corresponding snubber. After having my tech gin up a new RC snubber 3 or 4 times, I said screw it and stopped testing and had my tech make new snubbers and replace all of them (about 60 in all, IIRC.) He wasn't too happy and the higher ups weren't crazy about the delay, but that was life at the Rocket Ranch.
The RC devices you replaced are likely to outlast everything else, not being potted may help them to stay cooler and last.
That classic voltage regulator is fed from a transformer and it's primary goes to the servo chip, some jiggery pokery going on there lol :-D.
Servo just reminds me of pll circuits, old disk drive servos, and washing machine motor feedback speed control.
Servos can be a pain in old piano key jvc video recorders, "breathing picture".
"The RC devices you replaced are likely to outlast everything else".
Not likely, as they seem like metallized paper caps inside. Have you seen Wima and Rifa MP series EMI filter capacitors failing (the ones in translucent encapsulation)? I have seen, dozens of them. And they are still produced today for some mysterious reason...
Klien Tools are fantastic. I use them every day as an electrician.
Impossible to break.
12voltvids oh absolutely. They are built very well I must say.
@@12voltvids There's a reason we call the linesman pliers electricians hammers...
@@devicemodder Yeah I tested out the theory of the lineman's one day telling another tech. I'm about to cut this 240V line to test their 600V rating, after having turned the breaker off earlier. Turned out the joke was on me because I didn't know he had turned it back on for some reason & KABOOM!!!!!!
Well they definitely did their job very well, not even a little buzz. Although it did take out a little chunk of metal with, but I still use them till this day.
That was really interesting. I have an old reel to reel where the motors only turned really slowly. I never got around. To troubleshoot it, but I think I’ll have a go at it soon. Thanks for sharing
Had so much fun with my dads Sony recording using 2 microphones 35 year ago even when it stopped working I remember pulling apart, I stripped it down. I think now oh why
Another A-1 production, thanks Dave.
Had a buddy in high school who lived 1/4 mile down the road from a local low power AM tower. I remember calling him on his landline telephone, and hearing the station faintly in the background. I guess they would experience the same deal with all the electronics at the house. The thing we got the most amusement out of was receiving the station via toaster oven. Just open the glass door, and it would come out nice and clear.
Many decades ago a friend of mine lived near a radio transmitter. As Dave says, EVERYTHING electronic and electric in that house picked up radio. As you say, we could literally listen to the radio on his toaster. Interesting to visit, but I imagine it would be hell to live with.
This was a 50KW flame thrower. Still looking for the pictures of the transmitter. They had a big diesel generator there for backup power too.
The station I mentioned (WESX) is currently listed at a measly 450W. The station format, ownership, and broadcast tower location have all long since changed. But it wouldn’t surprise me if it may be the same power they were using with the old tower. Just a local yokel station, with the original tower built in the late 30’s, right next to the Atlantic Ocean. It was just enough power to push moldy oldies, car talk, local news, and polka Sundays, to half a dozen different towns, and at least one Black & Decker toaster nearby.
@@erikj.2066
We used to have a bunch of low power AM stations. Paul Carlson (mrcarlsonslab) has the old transmitter out of the radio station from Hope BC. He converted it to 160 meters AM for HAM radio use.I hand built low power FM transmitters right out of high school that were installed in small communities to relay FM from other towns into small interior towns. Was working for a small electronics manufacturing firm that mainly made CATV amplifiers and modulators. They made fixed frequency modulators and receivers for the CATV industry. Back then all the cable companies would receive distant FM stations and re-modulate them onto the cable system.
I remember hand building the power amplifiers for the transmitter. Based on the Motorola MRF317 RF amplifier, that could run 100 watts all day and barely break a sweat. We were limiting them to I think it was 40 watts as that was more than enough power to cover the installation. A 100 watt FM transmitter would fit in a box about the size of a CD player. I am sure some of those hand built amp boards are still on the air. As a junior tech my job was to solder all the components onto the board and build the enclosure, mount everything. Then it went to the alignment lab where an engineer would put it on the spectrum analyzer and tune it to the desired frequency. It was a summer job when I was 18. I think they paid me 5 bucks an hour at the time when minimum wage was 3.15. Once that project was done I was laid off as that was what companies did. Hire a tech for a project then when project was done, you were done too. That was the same when i worked for Sony in 83. Temp tech job to modify hundreds of brand new Betamax VCRs. Rewind kits, and capacitor rework jobs on brand new machines that were en-route to the stores, fresh off the boat from Tokyo.
Used to happen a lot with the folks who lived in the villages under the Rampisham SW transmitter station, Dorset, UK, remote central locking on cars would not work and Russian radio would come out through their toasters!
Not surprising really given the fact that Rampisham had multiple MW's of transmitter power and an impressive multitude of curtain arrays to match. Always a spectacular landmark, esp. when everywhere else is just farms for miles.
tx.mb21.co.uk/gallery/gallerypage.php?txid=1662&pageid=2481
Due to BBC Word service and other broadcasters budget cuts it's all but gone now and only a couple of the supporting towers remain (with other equipment on them inc. a low power TV relay). The site is up for sale if anyone wanted it although afaik it's been gutted, I'm guessing both for scrap value and parts for other transmitters still operating.
Following your video....I got my machine working almost. The left reel I cannot get to turn in play mode. Right side play works. It even records on the right...but the wheels not turning affects the recording. Do you service machines ? Being as you gotnthis model working...you seem to be the guy for the job.
I have a TC-440 deck and I've broken 3 belts for the reverse take-up, do you know of this problem.
Akai did use the combo resistor+capacitor on their earlier models such as the first solid state models (X-355, etc.) They went to separate parts after 1968. This was apparently due to failures with the combos and complaints from service shops.
All the Akai units I have serviced, which is not many, just the 3 I own have separate components. As you summed it up. High failure rates. I remember these going bad on the Sony units I worked on, and always did what I did here, made my own parts.
good job,again!
Those arc snubbers in Sony and Akai decks were always so problematic and would usually short when they fail, thereby jumping out the switch contacts they were protecting. In an auto-reverse machine this usually means the motor is trying to go in both directions at once since both switches are closed, causing the the stall mode in the motor. TEAC decks never seem to have this failure, the worst I’ve seen on those is the old Suzuki oil cap arc snubbers exploding on the old 4010 era decks.😅
Teac decks were top shelf. They are what everyone else was measures against.
@@12voltvids right on!
I have a question ? Are the speakers mounted inside. What are the plugs for the speakers I do not know for this, I am asking
Thank you
External speakers
those electricians scissors are the best. have a pair myself... found em on the side of the road.
one of those capacitors burned up on me 20 minutes after the came
0:20 yodelodel yodelodel yodelodel yodelodel yodelodel yodelodel ump pum pum
Dave, did I see that this machine “flips” the heads for the reverse play back. If so, how do they keep the heads tracking properly time after time of use.
Yes the head flips around. This is one of those "dumb" Sony designs.
Love how they say on the front "six head function"! Really, I count 4.
2 erase, and a record and play head that flips around.
Akai did it right with the deck I have, the GX265. 6 heads, all glass. 1 center mounted capstan / pinch roller. 3 heads for each direction.
Yes, and mine (tc440) stops rotating after it sits a while. I have to physically rotate it by hand a few times to break it loose. Any suggestions on lube to free it up?
@@lindsaythomas2283
Well it depends on what is gummed up. Could be the capstan or the main motor. The main motor has an oil fill tube that will take oil into the motor bearing. A few drops a year is all that is needed. Don't put too much in, that is worse than not enough. Always use non detergent electric motor oil, not engine oil. Engine oil has detergents and polymers in it to trap combustion blow by, and it will gum up electric motors and other precision bearings.
Personally I use 3 in 1 electric motor oil. It is a very good 20wt non detergent petroleum oil. I use it on everything including clock mechanisms. If you can oil a clock and it is still running 10 years later with no ill effects then you know that it is good oil.
So going through 2 capacitors, you are really getting a 180 degree phase shift from your line current, correct? This should yield more torque.
Garamond? An unusual choice, but I like it.
29:50 - It appears to be drawing zero current. (?) Does it draw current if in 'play'?
No current registers on the meter and none is expected. It is just a phase shift from the main winding to create the rotating magnetic field.
Blah. I used to repair that Ampex / Sony R2R stuff back in the early 1970's - _ugly memories of those boards_ with or without the smoke. [shudders]
Great investigation. Well documented. Great repair! Like those stubby scissors - where does one get them? Looking at that schematic diag. I noticed another of those cap/res components (CP402) across a switch S401 What is the purpose of this use? Thanks for your excellent description of the phase-shift requirement for induction motor. Talking about the induced AM transmission into the fabic of the farm house - I knew someone in N.Van who lived under a power line - he used to light his house using old non-working fluorescent tubes induced by the over-head power lines!
The cp device job is to dampen the inductive kick from the motor when a switch opens. To prevent pitting of the switch. Think of it like a shock absorber. Called a snubbed circuit in technical terms. A capacitor would do the same thing or a diode in a dc circuit as is always seen placed across the coil in relays or solenoids. The series resistor is to protect in the event of the capacitor shorting as it did here. When the cap shorts without the resistor it would be a dead short. This would overload other components such as the run capacitor. When it shorts as it did here it becomes a resistor and basically nullifies the phase shift from the capacitor and the motor stops. When I put in the first pair pulled from the scrap board they failed right away probably because they were already on the way out. The only time they see any activity is when the motor turns off or changes direction and it is just a big spike of voltage.
The electrician scissors are made by Klein, but Miller also make them. You can buy them at home depot.
Can you share the schematic for that am transmitter that you build?
I have it here in pdf i believe.
Nice 👍🇫🇷
45:30 Time to build a Faraday cage around that lab!
Intentional radiator. I should put a long wire antenna on that thing and see how far it goes. Right now it goes about 1 block.
Good video! I have the akai GX365 . Instead of the heads flipping around, it has a plunger solenoid that that moves the heads up and down for auto reverse. The manual says it uses a hysteresis synchronous 3 speed motor (2-4-8 poles) . The more poles the slower the speed? I opened it up once and its relay city inside.
Don't remember if you said so; but did changing the cap/resistor change the wow/flutter problem it had?
The cap/resistor has nothing to do with wow and flutter. The pinch rollers affect that more than anything. The cap/resistor that failed is part of the proection circuit that protects the switches from induction arcing created by switching the motor on and off, or changing the direction. The snubber circuit. The There is normally no current flowing through it. If there is then there is a problem somewhere else. That is why I put the meter across it. 2 of them failed, and when I swapped them out for 2 used ones they also failed. I have to sum this up to the old parts on the scrap board I pulled were likely also bad, just hadn't puffed up until voltage applied. I could remove them completely and the unit would run just fine, and some techs did just that as the motor will run just fine, but sparks created in the switches will cause an audible pop in the sound when the switch activates, and it will eventually pit the contacts on the switch.
Components CP403 through CP407 are snubber networks.
Their purpose is to suppress any arc that may occur in the switch.
CP403 and CP404 protect S403, CP405 and CP406 protect S402, and CP407 protects S404.
The snubber networks play no part in either the direction or the speed of the motor.
Snubber networks like that are still in wide use today, even protecting solid-state switches.
They are readily available from commodity parts vendors (DigiKey, Mouser, et.al.)
They are not anything custom that Sony cooked up. They are widely used in many places.
The capacitors in them are much too small to affect the phase-shift that makes the motor turn.
As noted, it is C406 that generates the phase shift in the lower winding of the motor M.
C604 is a large metalized paper capacitor that physically resembles a modern electrolytic.
But it is made for motor start/run applications. Many of them are failing now decades later.
Fortunately, replacement polypropylene metallized film capacitors are readily available at sensible prices.
S404 switches between providing full mains voltage (117VAC) to the motor for FF/REW spooling
vs. turning the flywheel/capstan at the selected tape speed (via 90VAC modulated by Q501 and the servo circuit).
This was a common servo circuit used in many models of Sony reel-to-reel machines of that era.
You can easily change the speed of the motor by changing a single resistance value in the servo circuit.
In the TC 440 this is done with switch S501-1 and resistors R501 through R506
R501, R503 and R505 are screwdriver adjust pots which calibrate the three tape speeds.
That IC used in the servo circuit (CX-032) is the magic part that you can't buy just anywhere.
There appear to be still some sources at premium prices.
Everything else in the motor and servo circuit appear to be replacable by commodity components.
Of course the rubber components (belts, pinch rollers, idler wheels, etc) are critical.
If replacement sources of them disappear one day, these vingage machines will be scrap metal.
I have a Sony TC-850 and a TC-654 Those things really were mechanical marvels.
Things are so much simpler and easier here in the digital era. :-)
Loved the video. Brings back memories of working on those things back in the day.
Right but when the capacitor shorts, it becomes a resistor and that will cancel out the phase shift from the motor run capacitor causing a loss of torque in the motor. The CX-032 is a custom Sony chip, that regulates the motor speed. The motor speed is set by changing the voltage at pin 3 of the cx032. That voltage is referenced from pin 5 going through resistor divider and speed control VR network. One could put a variable resistor between pin 3 and 5 and have a fully variable speed. I would imagine these chips are getting pretty hard to find today, and nothing else is available as a replacement.
I replaced literally hundreds of these cap/resistor networks in the snubber when I worked on these machines back in the early 80's Saw tons of them when I first got into the service business, but haven't worked on many since the mid 90's. The majority retired these old R2R machines, and I saw literally none for many years, untill I worked on these few over the past year and 6 of those are mine.
my unit is atasqued, jammed a play button, how to fix this??
Good Job
Something told me the caps that control the motor was bad. I never thought it was the motor. Just a hunch.
Motor won't cause this. Loss of phase shifted winding will. So capacitor is the likely culprit. In this case the cap in the snubber shorted and turned it into a resistor which effectively canceled out the phase shift. The unit will actually operate without those parts BTW. They are protection circuits to protect the switches from pitting when they are turned on and off from arcing.
@@12voltvids Oh, OK then. That helped.
40:06 Best technician moment ever XD
Is c406 doing the same thing as the other 4 RC components? I don’t see an equivalent on the other end
No C406 is the phase shift capacitor for the AC motor. The other components are protection components to protect the switches from induction kick back.
12voltvids Ah ok thanks. So that one cap c406 phase shifts for every function of the motor? (Rewind, FF, play)
@@mrsemifixit
correct c406 created the rotating magnetic field in the motor winding.
Burning rubber?(belt)
thanks for video, my sony PLAY button hard jammed stucked, please, help me
Mechanism for the play button must've seized in some fashion. It'd be a good idea to attempt lubrication of the critical parts of the mechanism.
@@rawr51919 I will follow your recommendation mr colton, thank you for your advice
I have a Sony tc440 just brought have same problem you fixed in your video, l didn’t get the size of the compascitator and resistor used in duplication of the original one. Can you send a reply.
It is a 0.033 and 120 ohm resistor connected in series.
Wanna seen The 10 old 40 barn very cool
I've got an old Sony TC440 that I got brand new back in the early 70's from a friend who was stationed in Japan. It needs worked on similar to what you did to this one. I can ship from Akron, Ohio. Can you work on it? Thanks
Very odd Sony product. The only one of this era (1971) that had Wollensak-style transport buttons!
I wonder if the people who leased to the radio station lived till the lease was up.
The barn door to the transmitter shack had a warning sign about high rf levels on it and the new site on the other side of the highway also has a farm house on it but a big metal gate across the driveway with the rf warning sign on it. Now the transmitter building has 2 50kw am stations in it. 1040 and 1410 and 7 towers out back in the field.
@@12voltvids Many radio and TV stations in Portland Oregon have their towers in the west hills of the city. Because of the spectacular views, there are very expensive neighborhoods in the same areas. There is also a high cancer rate in those neighborhoods, particularly among women who can afford to stay home during the day.
@@BlankBrain
I don't think there is any denying that there is risk with exposure to high RF radiation. At work when we work on poles that have cellular antennas on them we have to power them down before going up. Most have a switch located about half way up the pole so we can power the unit off before going up to work, and these cell antennas I am talking about are only 4 watts.
Imagine constant exposure to high power UHF t transmitters pumping out a couple hundred thousand watts of ERP.
I remember when channel 21 went on the air here in the gulf islands before they moved to channel 10 back in the analog days. At the sign off every night they would announce their transmitter power. See the sign off for UHF and VHF here: 1234 KW on UHF VHF 325KW visual 65KW aural
UHF - ua-cam.com/video/h_Svj19-qpY/v-deo.html
VHF - ua-cam.com/video/-7zp7Y09xMQ/v-deo.html
That's a shitload of power. Wouldn't want to live anywhere near that transmitter.
Are you aware of a mod that includes adding a board to a reel to reel? I have an old tascam 22-2 with an extra board that is connected to the play back head and has a multi pin connector that i wonder is for? There also evidence of jumped pins on the the decks boards. I migh thave ran this by you before... uhave a email I could send you a couple of pics?
I am aware that some have added a direct play head output so they can run low level to an external preamp. Some people prefer to use a tube preamp as opposed to the solid state in most recorders because they consider the internal preamp inferior.
Sony makes them fit in a sleeve so you can built this in a cabinet like console stereo. The speed seems a bit wobbly at 3.75 but maybe its my ears.
Its wobbly.
I have two Sony TC-580 reel to reel l brought for repair. Sad to say they both have the same problem. Will play when torque resisters are cold, but reels slow down and stop when resistors get warm. These resistors controll ffw and revw torque,# rwh30j150-m and rwh20j1k-m. Any suggestions on how to fix?
About you am transmitter, I hope the antenna isn't connected to the ground. AM transmitting station always Isolate their guyed mast from the ground which makes them very fragile on some weather conditions
My am transmitter just is connected to a 9 foot piece of wire suspended from the ceiling. The station I visited has towers mounted on insulators mounted on raised platforms.
Yes the magic of AM radio, it’s even possible to listen to a station without using a battery or be connected to grid (the old way, crystal receivers that also were used on ships in the beginning of previous century)
@@pitsnake
Yes the good old crystal set. First radio I built was a crystal set.
The sound of AM ? its BAD slap dash radio stations sill use that in the UK .
TONE DEF !!!!
These were always ugly units to work on
I wonder if they tell you who watches most of your Videos ?
27:23 Oooh, no... Fake Rukycon (ruKycon, watch closely) capacitors....
No wonder the hybrid RC blocks failed: for me the capacitor inside looks like metallized paper. Should have replaced all of them with PP or PE, as they go unreliable after 15-20 years, and this unit is much older than that. Just like the RIFA and WIMA MP series EMI filter capacitors in translucent encapsulation. They are garbage, blowing up in everything, and they are still produced today. I really don't understand why these otherwise reputable manufacturers do this, as their 'explosive nature' is well known in the industry for at least 20-30 years now. I don't know how these parts comply with X2 and especially Y2 safety regulations, as I've seen PCBs with holes burnt in them by these MP series firecrackers.
what do you mean snubbers cant be sourced now ? of course they can , you put in parts that are just as shit as the ones you took out ?????????????
I do not know how you can fix something in such a mess on your bench.. Sorry.
My bench is clean compared to many i have seen in working repair shops. Poke your head in the back of a busy shop and see how it looks. Units ripped apart all over the place. Seriously. Sure there were some slow places where the guy had time to clean up between repairs because there was no work. The last year i was at the shop the place was spotless because there was no work but in a busy shop there is no time to clean up after every job. I clean my bench when i have nothing to do which is never because when I am not working on something I am nowhere around the shop. I spend as little time as possible in the shop. Seriously though go look in a busy shop and you will see it looks exactly the same. Back in my repair days we hired a guy that was very particular. He put every tool in a specific place and had an outline around it on the punch board wall where he hung every tool. He was very anal about sweeping his bench after every job. He did about 1/4 the work I and the other tech did. The boss noted this and gave him an ultimatum. Increase his productivity or look for another job. He quit. Time is money, and sweeping the floor and bench doesn't bring in any money.
@@12voltvids I am sorry, I did not intend to offend. I really admire your work as I do this as hobby since I was 12... Cheers.
@@georgemkirko9645
No offense taken. Just stating the facts. The best shops i have worked for or worked in always looked like a bomb went off inside because the techs are busy making money. We all have the same attitude. I am an engineer not a janitor. Want the shop clean, hire a janitor to clean the floor. I remember my first day at the phone company. I was checking the oil on my truck. One of the old guys came up to me and said. "Mechanics don't fix phones and phone men don't fix trucks! Put that dipstick away!"
@@12voltvids I would disagree on this... Those days long gone.... In our current world the most appropriate statement is - if you want it done right than do it yourself...
@@georgemkirko9645
There are still a few shops around. I have been in 1 recently and it looked like the shop i worked at. Plenty of units in various state of disassembly all over the place, some having parts picked off them. There aren't as many shops around but a few still exist.
когда говорят на английском особенно американском
русскому кажется что этот человек жутко всех презирает и во всех плюётся
Looks like it could have used a new belt. Great job otherwise. Thanks
The owner of it is more than capable of changing the belt. That is if the belt is available. Many of those are very hard if not impossible to find. Try to find a belt for a 3/4" vtr.
че за лажа
где перевод
Cho em xin một cái nhe