In the late 70's through to the mid 80's, I was working part time for contracted service center that was doing warranty service. They were servicing Sony, Panasonic, Niko, and some others. The managers of that service center wanted me to work for them because of my capability and knowledge. My main job was working in a major TV station servicing broadcast monitors, switchers, tape machines, routers, and cameras. I also worked a number of years in consumer TV and audio servicing. I used to service that model of Walkman. The man doing the video knows a fair amount, but he lacks some in debt knowledge of this particular model. This is normal unless having the proper training or a lot of experience with it. The pot that he pointed at, and I also saw it in the schematic he was showing later on, is the servo speed adjust for the transport motor during the play mode. How this pot is adjusted is we used a 1 kHz test tape. The earphone output was connected to a frequency counter, a scope, and a wow-and-flutter meter. The wow-and-flutter had to be less than 1% for the human ear to not hear instability in the tape motion. The frequency counter had to be measure exactly 1 kHz to know that the tape is moving at the proper rate of velocity or speed. The best I have seen on these was about +-10 to 15 Hz to the 1000 Hz reference. The batteries must be new to do this adjustment. The thermo resistor was to compensate for temperature change in the servo amp area to give more accurate speed with temperature change. Wow-and-flutter is usually fixed by replacing worn rubber parts, making sure lubrication is proper, changing warn mechanical parts, and the belts are in proper specs. We used specific frequency response tapes with tones to adjust the head height and azimuth. We connected the output of the player to a scope and a VU meter. The tape started at 20 Hz and had successive tones going up the scale to 22 kHz. That particular tape player if I remember correctly, with the tone boost set to default, it was able to reproduce from about 40 Hz to about 16 kHz with about +-1.5 to +-2 Db when working very well. It was very surprising. There were test tones to also verify for stereo separation cross channel coming from bad alignment of the head, or possible problems in the circuits. When working properly there was more than 47 Db of channel separation. The signal to noise at best was about 60 to 70 Db. The newer versions of the player technology had Dolby noise reduction. The newer ones were able to have a signal to noise of about 80 Db if I remember right. The sound quality was excellent for a small cassette player. With all of this it is important to verify the left to right phase. This was verified mainly with the 1 kHz test tape to start with. The total phase test had to be verified through the complete range using the main frequency response tape. The head angle adjustments would effect more the channel separation. The height would effect more the low frequency adjustment. The azimuth adjustment effected more the high frequencies. These all interacted with each other, and therefore it was important to keep repeating all the three adjustments until there cannot be any more improvement. The head angle with the azimuth adjustments also effected the phase. On this level of player it is more important to verify the frequency response and channel separation than the phase. The human ear would not hear a phase error in the sound unless it was more than about 20 degrees out, and that is a lot. If you look at the top cover of that player you would see a small hole located on the top of the playback head. This is for touching up the azimuth adjuster. To do the main head alignment the top cover is removed. Then the test tape is inserted. Once all the tone frequencies are verified, the test tape is removed and the cover is put back. Once the cover is put back, the playback response is to be tested again. The azimuth adjustment is extremely critical compared to the head angle and head height adjustments. Using a 10 kHz tone tape the azimuth is re-verified. This is the range for the high frequency audio where the human ear is most sensitive for loss of highs in music. The man did not know what the transformer was. This is a toroidal high frequency choke. The motor in that unit had to be well shielded. This motor is a DC brush type motor. The frequency choke was there to subdue motor brush noise from coming back out the motor to the circuit board. In the newer model they added a low noise transistor between the head and the amplifier processor IC for the sound. This was to allow for less amplification inside of the chip to reduce chip noise. The amplifier IC's back then were not as good as they were in later years. They compensated this with the added preamp transistor for the head. The newer version of that chip was able to be biased to have higher output and lower impedance output than the previous. Emitter output is low impedance compared to collector output. This is why they were able to no longer require the emitter follower driving the output amp. The man doing the review knew a lot more than the average, but he lacked some very important knowledge about that player. I am sure I serviced a number of hundreds of these and similar ones over a number of years. It is obvious I cannot remember most of the details I knew back then. Many of the problems were user caused and mostly mechanical. Normal problems were dirt in the mechanics of the player, worn belts, worn pinch roller, and cleaning and demagnetizing the head. I remember a number of them when new the heads became defective and had to be replaced. There were some where the users played so many tapes they actually caused some wear on the head surface and the head had to be replaced to bring it back to specs. This took over two years with a lot of use. When the head surface is worn it is more difficult to get the frequency response and channel phase to be in proper spec range. The circuitry was very well designed, and there were very few actual circuit faults unless the user did something very stupid. I remember seeing some where the output amp chip was blown. The users tried to connect the unit to big sound system amplifier and had electrical grounding issues. There were some people who tried custom things with these players and damaged them, because they had no clue to what they were doing. After warranty this unit was not cheap to service. If abusing of this unit the warranty was void.

I still have my TPS-L2 and it still works beautifully.. These machines lasted a lot longer than ensuing models is that it is made of metal not plastic. The design was meant to last and to introduce a new product that will spawn many followers. I also have my original SONY Betamax and it weighs a tonne since it is also made of metal. It also still works.

I wish manuals were that useful on todays products

If you use a batteriser with that, you can listen to your music 80% longer!

The Walkman was based on the Sony TCM-100 Pressman handheld cassette recorder, introduced in 1978. Turning it into the Walkman was simple -- they just removed the recording capability and gave it a stereo playback head (but they kept the microphone, for the "hotline" feature).

It wasn't just a small tape player, it was the first mini player that was actually made to sound really good, and it did. The small headphones were revolutionary and really made the walkman an amazing piece of gear. It did really change the way people were able to listen to high fidelity cassette tapes without having to be home or in a car. I believe it did the cassette format a big favor by building on it's popularity.

Absolutely love your enthusiasm! I'm an older guy who's been an electronics tech for 20 years now. The first 15 were doing repairs of consumer electronics, and automotive electronics (radios, control systems,etc). So I can relate to why you get all teary-eyed when looking at older service manuals. They don't make them like that anymore.... I even remember using schematics that were only on micro-film! I repaired 10's of thousands of car radios with cassette decks...and ya those pulley systems got better over the years. Now I'm a tech for the Canadian military... 5 years army communications, and soon to be air force comms tech. Love your videos!

They sound awesome btw. Own one I refurbished. They are built to last. It's truly a mini stereo! Also, the mini brass roller is a counter rotating flywheel. The purpose is to reduce wow and flutter when the machine is moved or shaken. High Low was for tape type, as Chrome tapes are recorder with a higher EQ than standard iron oxyde tapes. Later was replaced with Normal Metal tape selector

Love the teardown! Life without walkmen, discmen was unbearable. Since I've been all digital for almost 15 years it's great to see my old Sony friend. Vivisected. Good in ya Dave

I would imagine the " hot line " button and the microphone were on there so you could hear people if they were talking to you without taking off your headphones ... yknow , whacky 70's stuff .

Wow A blast from the past! I must have worked on 100s (really) over the years. 99% of the problems were mechanical (as you would expect), belts, capstan(s) slipping and top of the shop, dirty heads. We used to buy the belts 50 at a time. Many Thanks Dave.

Really cool teardown. Big thanks to the kind gentlemen who sent this in.

I love your comment at around 11 minutes when you mention that these things (volume control) weren't built to last yet, they're still there and still work! I would say that today's consumer electronics seem to have a built-in expiration date ;-) Great teardown thanks for making this video! Very inspiring, it gave me a couple of ideas...

I was a Hi FI Dealer in central London. I went to the original pre launch of this device in Londons Mayfair hotel in Park Lane. The original name at the show was the Stowaway, the concept was making your music stow away in your pocket or case. The name was dropped due to copy write issues and the name so it became The Walkman. Sony products were brilliantly designed for the day and they placed great emphasis on making servicing and repair as easy as possible. The inertial roller you are referring to is either the Sony Dual captain mechanism or in later cassette mechanisms auto reverse. It wasn't simply a wheel that applied drag to keep the tape tight. I were saw one of the players go faulty. The only problem pool had was if they dropped them and broke one that way. They were seen as marvels of engineering for the day and if you look at a modern simple player with converts files to USB you will find the mechanisms of those machines are junk. Because dealers where quite sceptical of the market for a Walkman I was able to buy most of the first shipment and I sold the lot with a few weeks. Happy days Jeremy Travis Teletape London

Great stuff! I am sure a drive belt could be found to get it up and running again. I bought a Sanyo copy back in 1981, and it still works fine.

Once you fixed this walkman, check whether it cuts out at 1.3V battery voltage, maybe the batterizer guys only had 1979's walkmans to test their product!

Reminds me of the cassette days! Truly Nostalgic!

This is my favorite kind of teardown. See if you can get one like in the commercial, Dave.

This is an amazing evaluation. Like yours, my s/nr is low at 60667 which I owned from new. After years of un use the motor drive belt whet gooey and broke with black sludge on the pullies. So I cleaned up & bought new belts and idler rubbers. After reassembly it no longer drives through the drive trains. Only the main pinchroller is driven. So it drags a tape out of the cassette and does not pull it back into the cassette. The Drive only engages the pinchroller if I hold down the play button, the FF or FR buttons. If I release finger pressure on any of these 3 buttons the motor stops. I am hoping nothing other than the belts were the problem and that somehow I jogged something in the drive train. The Manual does not help me analyse the issue in the same way you described what does what. In the drive train something is basically not working at all, yet all of the components are in-tact. Got any ideas what I awkward little widget is causing my issue? All I can see is the intermediate roller with it's 'hook and claw and fine hairspring' looks dodgy but I have no data as to how to fix it.

Good teardown, hope you get it all back working again. Super bit of engineering. Also that model has a clever mechanical auto-stop system which detects when the pick-up reel has stopped turning. Most cheaper units achieve this using a probe to measure tension between the capstain and feeder reel which is considerably less complex albeit less elegant!

Lovely stuff, so enjoyable as always. Only one little point regarding the mechanics which you did not make too clear, the most critical part is the capstan and pinch roller in the top compartment. below the capstan the big flywheel connects directly to it and this bit is responsible for pulling the tape past the head at the correct speed. The take up spool just collects the tape and supply spool applies tension. The cassette itself of course was part of the mechanism and applied pressure to the head with a sprung pad. Sony made a professional version which was nice but pricey.

This year is it's 40 years anniversary, thanks very much! Good job brother Greetings from #Algeria ❤

I remember I had one of those Sony Walkman. On the pinch roller I had to put rubber revitaliser to get it to grip when it was slipping. Man those were the day's. Thanks for sharing.

That data sheet is beautiful.... and whole player is just awesome. I had a slightly newer version, my god, did that thing ever do just the best job. Ironically, Sony's diskman was also a real winner in every way... not that a teardown of one would be nearly as cool as this one is.

Please keep doing these. I will never see this technology without your hard work As an IP attorney in a corp. working with a Japanese licensee in the late '90, I got a tour of their drafting rooms one day. Unbelievable. Row after row of draftsman toiling to draw those manuals. They were also the guts of their patents. We use old Macs running fancy things like "Chemdraw" instead. Crazy days.

I first heard this model with those whimpy little headphones in1980. Ni other product ever blew me away like the first time I listened to that thing. It was a true miracle.

The Sony Walkman has been in Ghostbusters II (1989), The Castle (1997), Rubber (2010), Super 8 (2011), and Guardians of the Galaxy (2014). Not exactly a complete list, but there are some very popular movies on it.

I pulled up the Wikipedia page while watching this video, the photo used for the original Walkman is actually from your mailbag segment, was added 8 days ago. Got the blue mat in the background and everything.

Holy cow, my mum had one of them around 1980 ish, crikey, that's a blast from the past

I was fixing a "modern" sylvania LCD HDTV and I actually found a service manual for it. FULL schematic of the power supply and digital board, test point voltages and even oscilloscope waveforms!

Oh man, I don't know if it was this exact model, but my dad gave me his Walkman when I was in elementary school and I LOVED that thing to death. I carried it with me everywhere. There wasn't another epic music player in my life until Diamond released the Rio, the first portable MP3 player. A teardown of a Rio would be neat! Maybe even figure out how to use the memory expansion port which they never released any memory modules for! My Walkman didn't have the 'hotline' button (which is actually a clever feature), and in addition to High and Low tone, it had a Metal setting. Never knew what that was for.

My dad had a TPS from 1982. The belt dried out though and Mom threw it away. That could have been big bucks right there.

Another classic video Dave, thanks so much for making these retro teardown videos. Thanks and a big hello from saint cloud Mn USA. Cheers!

When Steve Jobs got one of these, he found it so fascinating he picked it apart just to see how they crammed it all in there.

Early motor were mechanical governor type. Perfect speed across a wide range of voltage. No problem. Them come the electronic control speed in open loop fashion, most by Philips. They use current being draw by the motor as a way to figure the "mechanical load" and adjust the voltage send to the motor to compensate. This crude approach has been WIDELY used in portable, in almost every boombox, and even in good quality decks, because the motor itself was so good quality that this idea worked fine. It was called negative resistance approach (trying to cancel the internal resistance of the motor). But this sony uses the FG type. This motor type approach is really uncommon to this era, most like a prosumer grade. The FG motor ouputs a tone with a freq. proportional to its speed (like a tacho) so a controller can lock the speed to a reference. Pretty advanced. Note that five year ago, Sony had the TC-55, a portable player recorder MONO, no bigger than that, case take appart in the same way and motor is horizontal (this is RARE). So no wonder how they get this prototypes so fast. First portable stereo was the TC-132 "shoe" box type. Well, it was a portable after that and it was stereo (WOW) with stunning 1Wx2 RMS power .. YEAHHH

Nice video and nice master piece of electronic.. I grew up with these devices and now I collect them

Very Interesting Thanks Roland, Max and Dave.

was waiting for the sniff the year part...LOL got love the power of the EEVblog nose for production year....

In 1990, I got my first walkman, I really wanted a Sony, but could only afford an Aiwa lol, I remember being very disappointed in myself, not saving up enough money, but the Aiwa did me well, it really sounded good, played loud, and even had an EQ on the door, in 97` it finally died, as I landed on it when I crashed my bike :/ But, I proceeded to get a Sony walkman, a minidisc, another minidisc, then in 2001, I also got my first sony mp3 player, the minidisc player that didn`t get stolen I still own, and it still works :) Now I own 3 Sony mp3 players, and like to use them instead of my Xperia, both saving battery and having an excuse to not answer the phone, because I was listening to music hehe ;) Besides, a LOD (line out docking) cable into a portable dac/amp makes sure it sounds fantastic, AND gets loud :)

Put the Belt back on the rollers correctly and that thing would work like a charm!

Azimuth adjust port on the front? Nice. Your IPod doesn't even have that! PS: You don't need bias if you aren't recording. I'd love to see a portable with a flipping (or moving) head! The few I've got just have 4-track heads, and used the correct pair depending on which way the transport was moving.

I can remember my Dad having a walkman in about 1983 or so, with the orange ear covers on the headphones and a large orange button on the headphone lines to lower the volume. I still remember the buzz the motor spinning up made in the headphones, had some pretty trick tape transport buttons also (green light on PB button)

I remember my dad having one and taking it to Boots the chemist to be 'serviced' every few years.... how times change.

Tape tentioning is done by the pulling action of the winding wheel in the cassette,it's coupled to the motor via slip drive.

I had the one from your opening video - absolutely loved it - it fit perfectly in my ski jacket and the headphone/earbuds were very light.

Anyone else forgot it was a video and tried to scroll through the pdf? Probably just me.

Triff to see the old Sony Walkman discombobulated, all those solder blobs, and the complex mechanicals! I recall my 1980's super-duper walkman, which had a bad solder joint that constantly failed, and no amount of tinkering would permanently fix it, many hours of listening to Pink Floyd, Queen, Split Enz and other 80's music, a great device from an age gone forever.

Please do more vintage audio gear

Thanks for the link, I was able to find service manuals for a Sony TCM-2 and a WM-F10.

The walkmans were long before my time but they look pretty damn cool.

Nice to see a real classic!

I had one of those "clip-on-casette" players by Sony... State of the art at that time!

A great video. Brought back lots of memories. Dave Robertson

That service manual was amazing...

Thumbs up for the great documentation review.

I had one, still have it :). Of course that made me king of the hill back in the day... I think it said "Soundabout" (not "Walkman") on the box if I remember correctly. The "hot line" button and the microphone were "remnants" of the (mono, I guess) tape recorder the TPS-LS was derived from (somebody at Sony must have said: let's leave the mike and the button in, it would cost more to change the machinery, so let's add some fun). Likewise, the second headphone jack input must have served as a mike input in the predecessor.

I have one of those tiny casette-tape-case sized walkmans from the intro around here somewhere still. I remember going with my father to the Sony Store to buy it as a christmas gift for my mother. Probably close to $500. It was AWESOME! It runs on 1 AA battery for hours and hours and hours. I used it for years until I got my first DiscMan (D-202 IIRC) in early high school. I'll have to try and dig it out and make a video, though it will probably need some service after 20+ years idle but I have the service manual around here somewhere. *SO* nifty, though... Fanciest Walkman ever! It slides down into the size of a casette case when no tape is in it!

Of course they still make service manuals like this, they're just not part of the standard consumer package. I was able to repair my 2006 Minolta DSLR with a very precise Minolta service manual, which included schematics, technical drawings, disassemble instructions and part numbers for everything. It's just that the average user doesn't want to have to do anything with that.

24:10 --- Now THAT'S why it's called a teardown!!! ;)

BEAUTY !

Having coffee this morning & listening while this in the background build building a new 3d printer. Love the Walkman tear-down. (Although I'm not sure if its the coffee or the ausie voice waking me up!) cheers :)

OMG! I so remember this guy from my youth. Too bad smell-o-vision isn't here yet. -.- The pinch roller is what actually restricts the speed of the tape due to the circumference differential between the start and end of tape which is why the part that actually engages the tape spool has a friction clutch on it. The back of the friction clutch has the auto tape end stop and it's all those secondary gears engaged by the 2 different friction rollers that provide the further reduction for play. You can actually hold down play partially and press FF or REW and hear the music mickey mouse'd. ^_^

I really enjoy the Australian sayings Dave uses! "bob's your uncle" and "what a bobby dazzler!" I am just not used to it, so it sticks out to me. Great video!

Fab teardown. The terrifying thing is that it doesn't seem all that long ago...

The 'Talk Line' feature was mostly used to prevent you having to turn off the cassette to listen to your mother saying 'go to bed' :D

There were some before this that actually started this, but this is the first one that was labelled a “Walkman”.

If your going to have the camera so close to the device stop fidgeting with it. its like watching the worlds cheapest carousel. Just leave it alone unless you are highlighting a feature. Apart from that good throw back teardown.

Love those retro teardowns!

This made my night! Thanks Dave

I had the US version called the WM-3. Terrific sound. I never used the "hot line" talk-over switch, which eventually got dirty and caused the channels to drop out a bit. Finally the belt broke and that was the end of it. Had I been a bit older at the time I might have been able to repair it. I never had a better quality portable tape player than this, though. The models that came out in the 90's were plastic and much more cheaply made.

Pinch roller or Rubber roller are useful to lack on place and pass it on tape along with other mechanism.

Not just transistors in these SIL housings, truly integrated circuits. Those japanese products were used pretty advanced stuff back then.

Holy crap. I just realized in like flynn is a tron reference.

Holy cow those things are expensive. I had an original sony walkman since I was a little child, I kept it and had NO idea they're worth hundreds of dollars now!

It's easy to laugh at old gear like this now, but in the day this was high tech and quite amazing. You gotta respect what this product meant at the time. I don't find it amusing, but rather quite interesting.

I still have my one and in good shape. If I change the belts I am confident it will work.

great teardown. :) That "Hotline" button. What a terrible idea. lol xxx

Do I smell a "Dave Jones Slaughters the Classics" cover album coming soon?

I had one when I was little 😊❤

0:29 Not to nitpick, but I just had to point this out: The 'ultimate' Walkman would be the last one to be released (maybe one of their new gimmicky audiophile PMPs?), and the one in this video, being the first one on the market, is the direct opposite of that.

Sony doesn't give a series of serialnumbers to a specific product. The serial number is just sequential to the previous product which rolled off the assembly belt.

Dave maybe you should make a series of basic electronics for programmers. I'm a programmer who has always kind of watched your videos without really understanding quite a lot of the fundamentals and would quite like to get into actually making electronics, and I presume there are quite a few others like me. edit: dammit, swiftkey

That belt looks fun to remember how it runs when you're replacing it! lol

The technical information and schematics are phenomenal! These days manufacturers don't give two hoots about after-sale technical support. Even if you contact customer support with a ticket, often they'll just gaslight you and say that your problem is "normal device operation". Any excuse to avoid supporting customers.

THUMBS up before I even watch it!! looking forward to this teardown.

Great teardown Dave ! I particularly enjoyed the schematics, proper old school stuff, them where the days eh ! I never liked the name either, I always called it a Sony Walkabout !

Changing the transistor positions maybe improved gain while reducing current demand & hence extended battery life? While it wouldn't have been 'dramatic', back then every second more it ran on one set of cells would be a win.

Don't forget the cover sheet on your TPS report!

I've a few early walkmen and the all still work!

I had one of those with matching orange headphone. Shame battery life was so bad and expensive.

Lol that communication thing, so funny.

Sony's manuals are still excellent- when they are available. I maintain Sony cameras/recorders and have been to three 2 week maintenance training courses. It is interesting that some of the same style can be seen in a Sony manual written 30 years later. Unlike some of their competitors, their English manuals have almost always been free of bad grammar and spelling.

Very cool. I can remember my first walkman that I saved up birthday and christmas money from Grandma to buy. I was coveting another kids Toshiba KT-S2 because that came with a "cassette" that when you put it in the walkman, you could listen to FM Radio! My dad got DAK Electronics magazine and in it they sold a clone type device from Kyocera called the KLH Solo which I could afford. The key to this was it also had a cassette that would get you FM. Oh, and by then yes, they had Auto Reverse.

Just a thanks for posting this video on KZfaq. You make a video that is interesting to watch. Great Job. Keep them coming.

I have two working Sony WM2 Walkmans from about the same time.

Bit surprised, with the knowledge displayed you didn't fix it. Noticed a few blown caps, just before you showed the paper manual/ schematic bits. The belts can be changed pretty easy and cheap, especially, like I say you have the knowledge, and it's already been opened, taken apart. It would be nice to think these tape devices no longer use belts, which WILL fail with time but even my newest and most advanced personal stereo is still reliant on a belt for it's function and of course, in 2022 needs a belt replacement, and currently doesn't work, you kind of mention the belt driven from the motor is an indicator of it being old tech, yeah the whole thing is old tech but as far as I know there was never a significant redesign of the tape driving mechanism that doesn't rely upon a belt for overall functionality. However the biggest flaw, I suppose with audio tapes is the physical wear and tear upon the tape itself, everytime it is played, the quality of the audio gets slightly less

Nice capstan flywheel! Wonder what the wow and flutter was like? Clydesight would approve

I had one back then too here in the USA

I've got one of the newer ones (WM-BF23), it's a different design, but as far as I can remember it still has only one motor. I had to swap out one of the black belts for a regular rubber band. Still works, I use it to play Pink Floyd through my stereo... :D

I hope you are able to change that belt and get this puppy playing again.