Restoration Project #21 - Technics 615 Tape Deck

Рет қаралды 9,524

Күн бұрын

As you might have noticed by now, I am collecting devices for a retro HiFi system; based on restoration projects. I can't afford "true classic devices in mint condition". So I go with "untested", "for parts" or "not working" listings that peak my interest. These are usually cheap enough and - when they are at least complete - usually can be restored with a few spare parts and lots - that is LOTS - of time.
This is the story of a late 1970s tape deck by Technics, the model 615. It was featured on @Techmoan - which I didn't even realize at the time I ordered it. It just looked like an awesome tape deck: VU-Meters and record level adjustment for left/right channel... as well als Dolby B.
By the looks of it, the unit has been stored in a garage somewhere; the layer of grime looked to be some soot from exhaust: both oily and dusty at the same time.
Spare parts: new belts, some LEDs and resistors, a new set of electrolytics and a bit of heat shrink. Consumables include a bit of black spray paint and lots of solvents for cleaning.
Donate a few bucks for some coffee (or some equipment upgrades)
ko-fi.com/atkelar
Chapters
0:00 Intro / Specs
1:10 Disassembly / Drive Belt
2:00 Desoldering Wires / Disassemble and Clean Mechanics
3:29 Desoldering Components and Cleaning Switches / Electrolytics
4:50 PCB and RCA Plugs Cleaning
5:25 Case Painting / Tape Sensor Epoxy
6:05 Caps and Switches Resoldering / Pad Repair / Flux Cleaning
7:08 Mechanics Assembly
8:49 Component Assembly / Tape Counter / Flip Door Buffer + Spring
9:58 LED Mod
11:05 Power On / Tracking / Speed / Other Adjustments
12:14 Mechanical Issues / Case
13:15 Test Recording
14:30 Overview: After / Credits / "Outtake"
Music:
My Train's A Comin'
Unicorn Heads
(KZfaq Audio Library)
"Blizzard" by Luchs - / luchs

Пікірлер: 90

@ericprentice1269 Жыл бұрын

Wow! This was the first cassette deck I purchased when in college at FSU 1978. Thanks for posting this!

@produccionespipa 2 ай бұрын

Una genialidad !! Estoy asombrado con el nivel de detalle que has trabajado.Fekicitaciones .

@areathra 3 жыл бұрын

I admire you my furry friend. I always loved taking things apart to see how things looked and worked inside. The only problem I had was putting things back together.

@atkelar 3 жыл бұрын

It's not that hard really... just repeat the steps in reverse! 😜 - I do get the point though; it took a bit for me to move on from just taking things apart to putting them back together too. I can't recall how many radios/TV sets I distributed around the house as a little kitten 😊 It was a good learning experience however. Taking things apart without breaking parts is the important first step and that requires a bit of experience in how things might be connected.

@gerrybvr 3 жыл бұрын

Your attention to detail is beyond impressive. Another masterpiece.

@atkelar 3 жыл бұрын

Thank you very much!

@paolopernigoni Жыл бұрын

Really fantastic!

@QuitProcrastinating Жыл бұрын

I have recently bought one of those. Looked pretty but it was rather neglected, some crappy motor was put in and it turns out the head is badly worn. Hopefully I’ll be able to get a replacement. I’ve used this video a lot of times now for reference so huge thanks for making and uploading it!

@atkelar Жыл бұрын

It is always nice to hear that my little projects help! I am not sure about the head issue though; so far, all the tape related devices I got - which isn't that many admittedly - were in pretty good shape on that part. Mostly mechanical and other electrical issues.

@QuitProcrastinating Жыл бұрын

Well, I was skeptical at first too, but there are clues. First, the signal really drops off at higher frequencies quite badly and no matter how much I fiddle with azimuth both channels play at different levels. I can also see that there seems to be varying phase shift between channels that’s dependent on frequency. I thought it might be the electronics but measuring the signal after second transistor (only then it comes out of the noise floor) with an oscilloscope shows the same thing as on line out. Swapping the head leads swaps the problem too. The head is also visibly worn down, there clearly is a ridge where the tape edge was riding (0.5mm or more) and the epoxy between laminations looks deteriorated. Do you think it could be something else? Judging by the swapped motor I think this unit has high mileage on it. I got a different motor and it too had play and whined like crazy. The bushings are somewhat removable so I squished them slightly to make them narrower. Now the mechanics work perfectly, it holds speed nicely and I got auto stop to work with a little encouragement from your side :)

@atkelar Жыл бұрын

The way you describe the head, I agree: worn out. There should certainly be no groove on it, since that would make it next to impossible to adjust any alignment issues. I think so far I just got lucky. I still have to check out if there's any source for these heads out there. I am pretty sure they were not really a "standard off the mill" item, so finding one that is compatible from the electric and magnetic characeristics might be a challenge. Mechanically, they should all be about the same size and as long as it ifts, the mounting holes and braces can be "adapted" :D

@QuitProcrastinating Жыл бұрын

I’ll try lapping the head so that it makes good contact with the tape again. Maybe that’s gonna bring it back somewhat. I did find the same head in a Greek shop, hopefully it really is in stock. I bet some heads from other decks would fit without any modifications but adjusting them for good playback and recording might be tricky.

@atkelar Жыл бұрын

I'd like to hear about the rsult of the lapping experiment... it might equalize the two channels, but I doubt it will get the head back to proper response; part of the magnetic core is worn off, and magnetism is next to RF black magic almost, and the signals involved are minute

@aleksanderjancar2896 2 жыл бұрын

This cassette deck is my first one bought in early 1978 and it is still alive. I really apreciated the great work you've done in restoring your Technics cassette deck. Great indeed ! So much respect and greetings from Italy.

@sorbusmusicconstructionunl7127 2 жыл бұрын

A Technics 615 was my very first tape recorder. It died somehow. Then last year, gripped by nostalgia, I bought another one - it's from 1981. It's been running fine, but I thought it didn't have automatic tape stop, until I saw your video. Fortunately, I only had to do a little cleaning to make the mechanism work again, and while I was at it, I also did a little tuning of the motor, just by ear :) Thank you so much Atkelar: You've enhanced the enjoyment of my old machine , and now I have a reference to consult if I need to make other repairs in the future. Great stuff! :)

@atkelar 2 жыл бұрын

Thank you! I really appreciate when people take inspiration from my projects; it's what sharing the videos is all about. I wouldn't consider them reference material though; there are more detailed plans and documentation out there; But if it works as such, all the better!

@sorbusmusicconstructionunl7127 2 жыл бұрын

I know the feeling! :) Well, sure, but to me your video is a great starting point, if I ever have to take my beloved tape deck apart! Keep up the good work :)

@KamilPotocki84 Жыл бұрын

Please more audio vintage restorations!

@atkelar Жыл бұрын

I have a few more items in the queue, one might be done during the Christmas holidays, if all works out.

@cutterstrophal Жыл бұрын

Wow!

@mrocean1293 Жыл бұрын

I like this format! Restoring cool retro tech with a cat - this is what the internet is all about! I just recently bought this beauty and this is my first tape deck. It works ok, but I'll need to change the belts and properly clean it. And thanks to you, good sir, I'm now not afraid to do it! Also, I'm having a hard time finding any information or manuals online. Could you please share where you got yours?

@atkelar Жыл бұрын

Thanks! Changing the main belt shoul dbe rather simple. The counter belt is a bit more annoying because of the strange path it takes. As for manuals: I usually just use Google for that: look for make and model number and add "owners manual" or "service manual". There's usually a good PDF version amongst the first few results (try to skip the "promoted" ones) If the device was popular, chances are good to find such. But occasionally I also draw a blank and have to switch to "best effort" mode :)

@karimdailyjazz 3 жыл бұрын

very good restoration

@FangThePup 3 жыл бұрын

That turned out so well and hey, nice throwback with the auto pen ♡

@bobby676869 2 жыл бұрын

GRANDISSIMO TI AMMIRO IO POSSIEDO LA STESSA PIASTRA, E IL TUO VIDEO MI è STATO MOLTO DI AIUTO TI RINGRAZIO MOLTO. PAOLO.

@joyspring5643 Жыл бұрын

WoWWWW...fantastico!!

@verpeilus 3 жыл бұрын

Wow, so many things i must think and test before the Tape perfect working.

@atkelar 3 жыл бұрын

Oh yes, these devices have plenty of adjustments. Certainly an interesting project. And the main reason, these things aren't commercially viable anymore 😢

@bca321rafael 2 жыл бұрын

god job man.

@CorsAir2042 Жыл бұрын

Well made video. Informative and humorous. Best wishes .

@atkelar Жыл бұрын

Thank you! I am glad you enjoyed it!

@weaselbox6746 3 жыл бұрын

@atkelar 3 жыл бұрын

Thanks! It was a fun project and it works quite well again.

@_Azzychan 3 жыл бұрын

Hi Atkelar! Thanks for sharing your YT with Funday Pawpet!!!

@atkelar 3 жыл бұрын

Welcome! I'll share as long as they want to play them.

@MagicMaus29 3 жыл бұрын

Great work! That is exactly the treatment, I would like to give my recently made attic find - my TEAC Z-7000 cassette deck and my TEAC X-2000M tape machine. Unfortunately, I don't have the space, the time, the equipment or the talent. So everything that would be needed 😁 So I'm afraid the devices will end up on my shelf, as decorations and mementos. Nevertheless, it is a pleasure to watch such great restoration videos, to admire the work done and to dream 🙂

@atkelar 3 жыл бұрын

Thank you! I am still looking for some more organized space to put the restored stuff to good use ^^ - eventually I'll have to sell some of it, or my storage will explode. So "space" is always tight, no matter how much one has. Start small, work yourself up to the important projects if you want to give it a try... don't start with something valuable for obvious reasons. I have thrown out quite a large number of radio parts in my childhood ^^ - also, depending on the state of your devices, it might also not be needed to disassemble everything.

@MagicMaus29 3 жыл бұрын

@@atkelar Thanks for the motivating words! For me, perfectionism meets impatience. A very bad combination for such projects 😁 I usually make up for a lack of basic knowledge with a dose of logic and a lot of enthusiasm. At least that was the case in my youth, which was a long time ago 😉 The devices are optically in almost perfect condition. The tape recorder may have a maximum of 50 hours of use, for example. So, they broke by almost 40 years of 'standing' around, rather than 'running'. For me, they represent a great ideal value and lots of memories. That's why I would never sell or trash them. I've been watching restoration videos for weeks now and have already downloaded the relevant service manuals. I consider this as a first step 🙂

@zeca20081 2 жыл бұрын

Maravilha, isso sim é uma perfeita manutenção, parabéns.

@dominikmichalczak4941 Жыл бұрын

Just found this channel. Very relaxing to watch. Talking cat as an advisor/explain is a brilliant idea :) Quite a surprise how this Technics sounds good after recapping and service adjustments even with worn out REC/PB head. Now I got motivation to search for something like this and do similiar project. I got some practising because I'm collecting old ghettoblasters from 70's and 80's so this shouldn't be a big deal :) Best wishes!

@atkelar Жыл бұрын

Glad you enjoyed it! Replacing the heads might become an issue eventually... not sure how many of these are still made in a decent quality. But even so, it's not that such devices get the same use as in their original timeframe. I now and then enjoy the nostalgia, so I expect to get quite a few years of service out of it before it becomes an issue.

@dominikmichalczak4941 Жыл бұрын

@@atkelar Yeah. Those devices had hard times when they were fair new. In todays usage the head should last much longer 🙂

@sinanb3692 Жыл бұрын

@@atkelar Good Video! The heads made in China which are selled on Ebay are sounding quite good but they wear quicker than old heads but not so fast that it should become a problem

@studioYUTA 2 жыл бұрын

У меня есть такой. Мне он очень нравится. А в видео работа проделана титаническая. Супер!

@philipperougeron1515 3 жыл бұрын

Good Lord! What a restoration you did here! Very thorough and the muppet speech is great to! How long did it take you ? Respect and greetings from France! Philippe

@atkelar 3 жыл бұрын

Thank you! I am glad you like it! The whole process took about eight to nine days, but not "full time". If you include the "waiting for ordered components" time, it is about two weeks. It is hard to be specific, cause I have to keep the camera setup in mind for every step, even though it sometimes doesn't work out right and I miss stuff. But that whole recording thing slows it down quite a bit.

@jeangenie68 2 жыл бұрын

😂 😂 😂 Brilliant

@senilyDeluxe 2 жыл бұрын

I found one of those next to a dumpster (a black 612 to be exact). Someone has ripped out the rear connectors and managed to break the circuit board in four or five puzzle pieces (the biggest piece was about 1/3 the size of the mainboard). The mechanism was also missing a belt and several screws. Challenge accepted! (turns out only a few resistors and capacitors were torn apart and from checking the other channel's connections you could see what they were and where they went. (it now sits in a rack at the workshop in the Arcademuseum Seligenstadt where I use it from time to time) Luckily the switch contacts of mine were in better shape and not in need of cleaning. And you're not gonna make me disassemble the tape mechanism, if you delete this video, there's no chance in hell I'll be able to get it back together! :-) My guess at the slanted deck mechanism is that when in the late 70s front loading decks made top loaders unfashionable, they had tens of thousands of these mechanisms still lying around and had to get rid off these somehow.

@atkelar 2 жыл бұрын

It seems like a transitional phase from top to front loading indeed. The "let's use up our stock" idea sounds plausible indeed. Also, glad to hear about another device that is in proper use instead of a landfil!

@bca321rafael 2 жыл бұрын

atkelar, donde puedo comprar los respuestos para reparar cassette deck, belt kit, pinch roller, ect ? thanks note: exelente trabajo con tu deck.

@atkelar 2 жыл бұрын

(Assuming Google translate is correct) - My local electronics store has some generic belt sets, and for special needs I found fixyouraudio.com/ to be very well stocked.

@matthiasjagdm3949 3 жыл бұрын

Had to stop the video from laughing to hard after you said shiny

@atkelar 3 жыл бұрын

It was quite mesmerizing :) Compared to the dull surface before. They didn't clean the flux in the 70s and early 80s I think...

@ericj5627 Жыл бұрын

so impressive, surgical precision. I have this exact model that the right side is humming.any thoughts?Thank you

@atkelar Жыл бұрын

Really hard to tell without measuring a few points... if it's just the right side and the left is working fine, it's OK to rule out the power supply. But that's minor to begin with. It sounds like some components have aged badly, and form a resonancy circuit rather than a filter circuit. I might be biased but I would suspect a capacitor. If the hum is just "in addition" to normal sound, that would be reasonable. If there is no sound and just the hum, then it might be some other component... But I dare say that it would require a bit of poking with a scope to find the fault. (might also be a lost ground connection somewhere... reallly hard to say)

@theoabrams2079 3 жыл бұрын

thank you for the reply, I’ve just got it today and have it cleaned and almost ready to go. The only issue is that the speed is a little slow and wavy. Should I buy the exact belt from a kit on the internet because the replacement belt I have in is not thick enough ?

@atkelar 3 жыл бұрын

There's an adjustment trimmer in the motor - but I bet it's also in need of some lubrication. Whatever they originally put in was probably not expected to last over 30 years. 😁 As for the width: the pulley is made for a "wide" belt, but I don't think it has to be "as wide" as the original. On my unit, a narrower version runs fine. But a round or square one is most likely not going to work: the pulley on the motor is shaped to auto-center the wide belt and that won't work with one that is too narrow. It should self-center on the motor side. If it does, it's fine.

@redbishop71 2 жыл бұрын

Hi, what is the brand or model of the stencil you used at the end labelling the cassette? Thanks.

@atkelar 2 жыл бұрын

That would be a Rotring (or rOtring if you go by the brand capitialization) made technical drawing writer, model CS-50. It is made for these large tilted technical drawing desks and has an attachment for one of those ruler arms that come with them. A bit fiddly to handle on its own; I didn't include the full description, because it was a throwback to the time I restored it over here: kzfaq.info/get/bejne/qOCPqtGixrbMoqc.html

@neverordinaryyoursoriginal4127 4 ай бұрын

I just found the exact one, it plays tapes super fast! They sound chipmunk. Besides cleaning do you know what is causing this ?

@atkelar 4 ай бұрын

There's sadly plenty of reasons... but the two that come to mind immediately are: 1.: the motor speed regulation is not "extreme" accurate with this model - i.e. not quarz controlled or something, but rather trimmed to a certain DC voltage inside the motor. Usually that is only +/- a little bit however, but it might be worth checking if the voltage that goes to the motor is within reason. If not, the rectifier or filer cap might be off. 2.: the pinch roller might not be excerting enough pressure to hold the tape against the capstan. That would mean that the pickup wheel of the tape is "fast feeding" the tape, since the pickup has to run slightly faster than the normal tape speed. Maybe a weak, broken or just loose spring? Or, the rubber part of the roller might be way too slippery and hard and needs replacing.

@neverordinaryyoursoriginal4127 4 ай бұрын

Thanks so much, this is a new found hobby for me and I’m hooked! I also noticed the rubber belt seems loose and doesn’t seem to rotate properly. I’m going to keep at it 🙏 Thanks for your video I will keep watching

@theoabrams2079 3 жыл бұрын

Is it a good tape deck after all? I’m getting one tomorrow for 15 bucks to restore. Also what does the timer stand by button do exactly?

@atkelar 3 жыл бұрын

I think that - for its time - it is an awesome deck. Keep in mind that it's late 70s, so the auto-stop is only for the play feature, not for forward/rewind. For the same reason, it also has no "seek" (fast forward/rewind) either. The "timer" button is a bit of a strange thing: it acts like a second pause button. It can be used in conjunction with an external timer for automated recording: Press pause/play/record and then turn off the power. Then press timer and release pause. Once the unit turns back on, the tape will pick up speed and then release the timer button to start the recording "at speed" instead of "ramping up".

@maddy3030 2 жыл бұрын

Hi there I wanted a particular ic for my technics tr 155 deck , say would u be having them thanx

@atkelar 2 жыл бұрын

Not sure; probably not "in stock" at least. I am not a professional repair shop, I also order stuff "as needed". What exactly were you looking for?

@maddy3030 2 жыл бұрын

@@atkelar looking for a mitsubishi ic for my recording deck

@atkelar 2 жыл бұрын

Well, no, sorry; nothing from mitsubishi comes to mind. If you have a part number/type code I might poke and prod my usual sources. But just based on the manufacturer, I can't tell.

@mariorocafuerte417 2 жыл бұрын

I'm trying to restore a RS 630, mechanism is very similar but I have a problem: I don't know how placing the torsion spring (the part is showing in the minute 2:27). Do you have some diagram for this? I would appreciate replies.

@atkelar 2 жыл бұрын

You mean the one that is pushing down the pinch roller? Or the one that is pushing down the "end of tape" feeler? Both of them are visible in the referenced moment. The service manual elektrotanya.com/technics_rs-615us_service_en.pdf/download.html has an exploeded view, but that shows the springs in "relaxed" state, i.e. they need to be twisted about half a turn to pre-tention them.

@mariorocafuerte417 2 жыл бұрын

@@atkelar Yes, the one that is pushing down the pinch roller. I don't know how placing in the plastic part (pressure roller assenbly). I found the service manual for the RS 630, but it shows the spring in relaxed mode, as you mentioned.

@mariorocafuerte417 2 жыл бұрын

Update. Looking closer the pressure roller assembly, I think a small part is missing, just where the spring lies.

@atkelar 2 жыл бұрын

If I recall right, there should be a little notch for the spring. If that is missing, bending the end of the spring 90° and drilling a small hole might be the best way to go.

@mariorocafuerte417 2 жыл бұрын

@@atkelar I will try to build the notch using expoxi resin, I hope the notch resist the torsion caused by the spring. I am very grateful for your advice, suggestions and especially for this wonderful video.

@derkanal8879 3 жыл бұрын

Hello, I dont know if you read this comment. I have this su615 casset deck but the play button doesnt work. Do you have a mail adress or sth like that so we can get in contact. greetings

@atkelar 3 жыл бұрын

Sorry, no - Spam prevention dictates that I don't publish my e-mail I am on Twitter and Telegram - same name - but that's about it. You can also provide a description of "how" the play button isn't working: Is it stuck? Does it not start to turn the tape? Are the fast forward/reverse working?

@derkanal8879 3 жыл бұрын

@@atkelar thx I write you in Telegram

@colloidalsilverwater15ppm88 10 ай бұрын

Well, I have no patience to look how do you tearing apart such machine. You've must been profi in some factory, whilst you courage to take away every single spring, roller, metal etc.

@atkelar 10 ай бұрын

Well, I learned a trade in a factory back in the early 1990s but never actually worked as such; the PC side of things took off and I got sucked into that direction. I'm also aware that this amount of cleaning and tuning wouldn't be sustainable for a business: nobody would pay several thousands to get an old tape deck running again 😜

@colloidalsilverwater15ppm88 10 ай бұрын

@@atkelar Yeap