How to Add a Line-In and Bluetooth to old Stereo Systems (1)

My Patreon: / tpai
Paypal-Donation Link: Can be found on the bottom of this page:
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Earlier Videos about Audio Hacks:
Old Radios-Line-In-Hack:
• Old Radios as Smartpho...
Car Stereo Line-In Hack:
• Car Stereo Teardown, A...
Car Stereo Bluetooth-Hack:
• Hack: Adding Bluetooth...
Car Stereo-Home Stereo-Conversion:
• How to Convert a Car S...

[@mikeissweet]

Excellent and clear diagram. I like how you gave the extra effort to add the feature while preserving the original functionality of the device.

[@bachelorchowTV]

Explaining electronics in a way that beginners can keep up with is the mark of someone that knows their craft. You also do a remarkable job of including things to be aware of without bogging down the flow of information. This is really, really hard to do well and you executed it like a pro. I'm done gushing, great work.

[@ThePostApocalypticInventor]

Hey guys. This weekend I'm actually home and you can expect 3 videos until Sunday evening :) Enjoy!

[@parvatkishan3850]

That's awesome!!!!👍 eagerly waiting!!

[@bidders77]

great video!! thanks. it would be great to be able to harvest bits from an old stereo to make a simple amplifier with an input in a new custom box.

[@andrewbraini5229]

Thanks! looking forward to them!

[@ninjamaster3453]

good stuff man

[@titaniumdiveknife]

NO WAY¡¡¡¡¡¡¡¡

[@ianbutler1983]

A PAI video that is too long? Impossible! Thanks, I really enjoy your videos and appreciate the effort they require.

[@TheGroovebot]

Always informative, always an example of how repair videos should be made.

[@jeremiefaucher-goulet3365]

I'm currently modding a Lenoxx Sound CD-160 and discovered that the input MUX/Selector inside is actually wired and supports a 4th AUX input beside Tape/Radio/CD. So I can actually bake-in the missing feature by simply wiring a soft button to signal the electronics in making the the 4th selection for me. The onboard microprocessor, a TC-9309AF-119 already supports a button for selecting AUX, in it's matrix even though the feature is not offered by the boombox front panel. And the selection chip, a TC4052BP already supports switching between 4 sources by decoding the 2-bit signal from the microprocessor. The audio input pins for the 4th source (3X/3Y) are simply left floating on the PCB, so this is where I should tap myself to take advantage of all the selection circuitry already in place. This should yield a pretty cool, close to factory integration as I don't need to bypass anything, just add missing components: a soft button and a line-in jack. It's only sad that Lenoxx didn't offer AUX from factory considering everthing is pretty much there already on the inside for supporting it. I came here seeking more information about what I should connect as an input, assuming I can't just connect bare wires directly to the input selector switch. Surely I need some kind of filtering? Coupling capacitors? Protection from static or over-voltage? Based on what this video says, no I should be able to connect this directly from a 3.5mm female jack added on the front panel. I guess we'll see about that.

[@VladPKL]

Old NOKIA Stereo System?!?!? Wow, i never imagine that! :D

[@RinoaL]

3:33 wow those Varta batteries are cool! i have a small collection of old batteries at home. lol.

[@Seegalgalguntijak]

I've heard about an absolutely awesome build: Someone took one of these old cassettes that are made to put into a car stereo and have a wire with a headphone jack coming out so you can connect your phone. He removed that wire, and put in a small generator that is driven by the tape drive of the radio, and connected it via a LiPo charging circuit to a small battery, probably from the bluetooth headset as well. Then he took a pcb from a stereo bluetooth headset and connected that to the system as well, but on the output side, he connected the magnetic field generator that fed the audio from the headphone jack to the tape drive head before, and now there is a cassette that you can put into your vintage car stereo and have bluetooth audio capability. This is such an awesome product idea, I am really wondering why noone hasn't made a product from that yet. I think there are lots of people who would pay 20-30€ for that if it's well made. Or only 10€ for the China version ;)

[@drumintercourse]

For once your diagram and explanation didn't completely fly over my head. Very well done. I'm excited for part 2. I actually have some vintage speakers i picked up at a thrift store that Ive been meaning to repurpose.

[@H31MU7]

I have a wonderful old Sony that I really wished had bluetooth and line in, this video is perfect thank you

[@Abbadon2001]

I have that sony stereo at the start still in use in my workshop :) must be 25 yrs old or so, listened to kids stories on it when i was about 7 and it was my parents back then!

[@dozerjohn]

Oh man, Just as I am building my first audio amplifier for a pair of reclaimed speakers you put out this video, 10h after I started pondering on building another one with bluetooth, them coincidences!

[@borisznidarsic9346]

Block diagram is understandable and easy to overview. Great work.

[@abdulmsiddiqui4344]

Usually when the radio and amplifier circuits are on the same board, it is difficult to find the audio signal terminal. One trick I found was to touch the terminals (careful, do not touch any power circuit terminals) and the speakers make a low (bassy) sound if you touch the signal terminal. This is how I located it in my 90s Panasonic radio cassette recorder

[@HassanETECH]

man you are very apprciated. taking all that time to record the process and providing theories and explanation. all i can say wish u the best 👍

[@mrfrog8502]

This is fascinating. I never knew NOKIA did home stereo's or that ebay has a give away section in Germany. Thanks for this upload.

[@moritzrudolf5370]

It's eBay Kleinanzeigen, something like Craigslist.

[@sheep1ewe]

I must say that Your intro is wery good and inspiring. I hawe probably watched it in every single episode here, but i still love it wery much, and i still don´t want to miss a secound of it! There is no other video intro on KZbin that still inspire me in my daily life even when i hawe whatched it so many times. I would say that it´s just genious.

[@soulfreshdays]

Vielen Dank für diese wundervolle Inspiration! Ich hab mir vor zweieinhalb Jahren einen alten, relativ einfachen und billigen Panasonic Ghettoblaster als Küchenradio gekauft und das Gerät hatte nie mehr als FM und Tape. Ich hab mich eigentlich hauptsächlich darauf eingestellt damit Tapes zu hören (hatte damals auch extra den Riemen deswegen wechseln müssen), aber da der Mechanismus dafür relativ billig ist, es immer leicht zu schnell spielt und auch nicht gerade gut mechanisch mit den Bändern umgeht (alles verglichen zu meinen zig Hifi-HighEnd-Decks) habe ich es mehr als Radio benutzt, auch mit einem FM-Transmitter. Dank Ihres Videos konnte ich dieses Gerät jetzt mit zwei Cinch-Buchsen nachrüsten. Der Chip war einfach zu finden (einfach in der Nähe des Anschlusses des Tonkopfs geschaut), dann die passende Anleitung im Netz rausgesucht, drei Kabel für links, rechts und Ground angelötet, zur RCA-Buchse verlötet und fertig. Ist zwar primitiver als Ihre Lösung, aber ich bin auch nicht gerade der handwerklich begabteste. Und was soll ich sagen: ich bin zufrieden. Wenn ich jetzt auf Play drücke ertönt das Signal des Aux-Einganges (solange etwas angeschlossen ist) und sobald ich den Klinke-Stecker rausziehe kann ich das Signal vom Tapedeck hören, falls ich das noch brauchen werde. Vielen Dank für diese simple Erklärung mit der selbst jemand wie ich etwas anfangen kann, obwohl ich selten mit so etwas hantiere und liebe Grüße!

[@cassvirgillo3395]

Hi TPAI, I hope your having a good Summer & doing well. Great video, I always look forward to new TPAI videos. Great explanations of circuits and why and what the components are for. Thankyou for your time & effort making videos. Take care, C.

[@stevejackson2532]

Thank you for the videos. I look forward to them. I find them both entertaining and very informative. I have an old "boombox" in my garage with a selector switch that will make an ideal candidate for this particular hack. Based on the tones I heard when you fired up your Bluetooth device, I have the same device sitting on my bench too. Should make things a bit easier for me. Best regards, Steve

[@CoolDudeClem]

These should have had Line in from the start, that's how I would have designed them. I've had many stereos I wished I connect to other things. You could just get one of those FM transmitters for car stereos as a sort of "line-In" when you have the radio tuned to it, with the added bonus that I can record it. I don't give a dam about bluetooth and other "phone" devices though as I'm an analog guy. Cassettes, vinyl and mini-dsc (even though it's digital) is better.

[@1blisslife]

CoolDudeClem Go old skool Nokia radio... just need the matching Nokia cellphone!

[@HelloKittyFanMan]

Wow, with those batteries being that old and left in that boombox, I'm quite surprised that they weren't all leaky and and that he battery compartment didn't have that icky battery crud all over!

[@papaike2]

Brilliant stuff my man enjoy your channel.

[@hotrodroxie]

Ok! Your a smart guy... and I can’t seem to find anything helpful online. I opened my UNDERMOUNT KITCHEN RADIO unit & SPLICED IN 2 exterior speakers. My goal is to have sound on the deck; off kitchen! Here’s the problem I’ve encountered: volume control for the exterior speakers. With the kitchen sound normal, the exterior sound is too quiet.😞 💁🏼So, how do I ADD VOLUME CONTROL (w/CUTOFF) to the additional speakers🤔 An inline (speaker) control is an easy enough fix...BUT....the next problem becomes the INTERIOR sound must STILL be turned up too much- SO THAT the secondary inline control can do its job. Scenario: I have run 2 additional speakers (exterior) from my undermount kitchen radio- (they are spliced to the internal speakers in the unit; because I couldn’t find a better place to splice them) to the deck. It works fine, but there’s the volume issue. 💁🏼You want the exterior speakers to be much louder, but as is: the only way to turn them UP is by turning up the kitchen sound -which is then way to loud. So in theory, an inline speaker control would suffice the exterior control on sound... BUT the origin of the sound would still have to be HIGHER, and then the added exterior speakers adjusted thereafter via the inline control dial 😩 So is there a way to 🤔😂 AVOID turning UP the internal radio volume -in order to increase the inline volume to the added speakers???? Just hoping you have some input 🤷🏼‍♀️ I know it’s a longshot! Thanks!

[@nati032158]

this is so awesome!!! thank you for this!

[@robmallory]

Thanks so much for this. I attempted to do this on an old 8track player. I messed it up by wiring in to the pre-amp, with limiting resistors for the voltage from the output from phone, but it blew out over time anyways. I think that it was just to much for the pre-amp chip. Anyways, knowing where to line in from your diagram really cleared things up. Wish you would have given an idea of voltages, and power output from volume control from the earphone jack though, which was the problem. But thanks, fo rthe video, great job.

[@ninjamaster3453]

this works both ways too I assume. say you have a record player, tape deck that you want to hear on your BT headphone

[@TheSgio]

This video is really educational, thanks! ;)

[@continental_drift]

looking forward to the next part.

[@simonhopkins3867]

might do something similar just to help my learning curve.

[@Aperson-sv2hc]

You have a notification squad of about 221 viewers. Fans of small channels allways wonder why it be so small.

[@Nishandh_Mayiladan]

Passionate description.

[@edgeeffect]

Line out is useful too... for we "oldies" who have cassettes that we'd like to get onto our digital devices.

[@zx8401ztv]

Nice hack ;-D Did you put 2 x 47k resistors from L/R inputs to gnd to give the driving device a line level load, or was it not too loud?

[@edgeeffect]

They used to advertise Varta batteries in England as "from the Vartaland"

[@n8hfi]

The cassette pre-amp IC has a 1990 date code, and the PA IC has a 1991 date code. So I think the radio is exactly 25 years old. The original owner must have put in batteries they had on hand and never changed them. I'm impressed with the battery quality; not a sign of leakage.

[@fouzaialaa7962]

i only have 1 question !!! why not use the already installed power supply of the Stereo ?? why did you use an external 1 ??

[@arturomendoza7515]

Excelente video y descripción saludos desde México

[@orbitaaltube]

Hi Guys, I usually dont ask for help with my projects but my knowledge of electronics is only average. I have a HiFi from 1994 that does not have AUX input. I have the circuit diagram for this model and was looking for some help to understand the cirtcuitry to implement what PAI has done with his old radios here. The system is of sentimenal value as it was the first stereo my parent bought by as a birthday gift and the sound is also really good so I dont want to throw it away but Im willing to sacrifice one of its functions CD/RADIO/CD in order to add an Aux input. I have my own channel so I am also open to collaborating with other youtubers on this. many thanks.

[@ThePostApocalypticInventor]

If you can send me the schematics, I might be able to show you where the AUX can be inserted. If you can, send the file to [e-mail] cheers, Gerolf

[@abeleballestri612]

I have learnt quite a lot from this video. Thanks. I have a question:will it be possible to receive the new DAB system in the future in our old FM receivers? Will it be necessary to use them even with the new dab system? In Norway the FM broadcasting is dead now, what can we do to be able to get the dab system in our beautiful old radio fm receivers of th 60ties? I would be very grateful to hear your opinion if possible.thank you very much for your time and your wonderful videos you have made so far.

[@andrewwilson8317]

A very well explained modification. I have carried the same mod out but had a problem pairing my iPhone to the radio via Bluetooth. Probably something to do with security as it just did not want to pair up?

[@der0keks]

If you used a "headset" bluetooth module (like a hands-free car kit one), some of them wont play music if hacked into a radio.

[@filipinasantos2769]

informative and educational video, nice one, if i'm not mistaken u said on the video that you are from germany, am i right?, i understand very will your English not like others hard to understand, yes they are english spoken people but hard to understand the way they speak. thanks a lot for sharing the video

[@lmavi]

great as always

[@ThePostApocalypticInventor]

Part 2 is now online! kzbin.info/www/bejne/haakknuJjN92mLM

[@RegiPavan]

Very nice tips!

[@symik3]

Good video, I have worked on a similar project, last week, it had a input slector/ volume control/equalizer IC all in one, we hacked the audio input there, we got it to work but then we went back to make abetter connection to the pins, we killed our IC and cant fint another one. Sucks..

[@mohamad77777]

Excellent. Thank you.

[@ranger81de]

Awesome video, thanks!

[@bborkzilla]

25 year-old batteries that have not leaked? Best West German quality!

[@tarcisiomarques8784]

Awesome! Thank you!

[@ALEXCANNOL]

Amigo. Este video esta chingon.✌

[@simonhopkins3867]

very useful video. Thanks

[@OldSkoolF]

To clean crevices I use Paint Brushes, Q-Tips, and Toothbrushes... Wiha nice!

[@burvinators]

hi, i have an old sony stereo system, it has a aux in, but when i play a song from my phone thats connected to the system, it doesn't play, and theres no button or mode for aux... what should i do? thanks.

[@rodrigov2863]

Kārlis Vaitkus maybe you need to select the "video" function so the aux can work

[@HDXFH]

Belgian made philips batteries, ooooolllld!!

[@LiltonBravo]

Hey man sup!? Can you show us how to put a audio jack 3,5mm to connect a bluetooth trasmiter, then use bluetooth headphones, on a LCD TV?

[@Dylan_Lanckman]

I wonder if you could replace the source selector with one that has just more positions. I would then like to learn how to ad a display to it that tells me on what channel I am.

[@MDFRESCUER]

Good project.

[@daniellukonis]

Im glad Germany is one whole country now.

[@MentalPolution]

Ive done these steps and am now successfully able to play music from my pone into the RCA jacks Ive installed. My question and Issues that I dont know how to resolve is that the sound quality is low and poor. My only idea is to try better RCA wires/cables. Please help if you have any suggestions.

[@KobaltKeva]

Any way to also add a power bank option to an old micro hi-fi system?

[@marinesculucian6538]

Hello ! I have a Sony radio cassette player like the first one in the movie. Can you please tell me how I can use the speakers as speakers from a PC or another device. Thanks 😊

[@axelisaksson7273]

Can you do how to find a cheap variable spead to Three phase?

[@BigAdam2050]

Half of me is "well you could just some stuff from china to do that!" then I remember half of it is crap and the old school stuff seems to still kick it along brilliantly.

[@38911bytefree]

Gear from 20 years ago will outperform any crappy chinesse thing. They were built to quality. To get a proper 80s construction and quality, today you need to spend tons of $$$$$$$. That the reason why vintage gear has gone so high (prices) in those years. People relised how crappy actual audio gear is .. and is going back. some of them go far too back into tubes ... but this is BS IMHO.

[@38911bytefree]

Barry Manilowa Sure. Another issue is people not willing to pay for a good thing. Just have a look how expensive a Bose Wave Radio is, or their sound socks. They are pretty decent, portable, but too expensive. I havent seen a piece of chinesse gear built to quality except a valve amp. Of course they can build quality, but people is not willing to pay for it. Vintage systems are expensive but cheaper compared to any today gear matching that quality. Something is sure, you are not getting a Sansui 717 anymore. Even when paying because this bussiness model is DEAD. No one will care of every cap being elna, custom sanken semiconductors, metal knobs .... today that is premiun grade. Of course there are high end brand like McIntosh, but who on the earth can afford that LOL. Cheers

[@marchemar]

Hi, I just got a (very free) Panasonic SU CH-40. It works just fine, but I intend to merge all four units (amp/cassette, cd/radio modules and the 2 speakers) into one single volume, which i'll fabricate, chopping off both cassette and cd player on the way. I want to do this because it's just too clunky to have 4 separate pieces, and i want to be able to move it, and so, I plan to throw a bluetooth receiver in; but also, I'd like to fit it with batteries. Do you have any instructables on how to do this???

[@ramonebills9318]

Are you an electronics engineer?

[@dodgeramsport01]

Why not just run a fm modulator to your cd/ipod etc or the cassette adapter?

[@dankerine]

My radio has plastic caps over the heads of the screws and I cannot remove them as they are deep down, do you have any suggestions?

[@BGaborr]

what bluetooth module are you using? the ones i bought are having this high pitch noise problems.

[@hotshot3d]

There are Bluetooth modules that you can use now.

[@HelloKittyFanMan]

"...These old radios and sound systems..." * "...These old radios and _other_ sound systems..."

[@CanDoo321]

Thank you

[@tottimejdi5820]

that intro music lol

[@leonardobrocato3952]

My question is can i use this to connect it to a 32 inch display with 3.5m aux?

[@ultimateconcealcarry4671]

Is it possible to add a line in to a old car stereo that does not have a cassette deck, that has an FM AM radio?

[@pascalimero2000]

super video :) hab dich abonniert !

[@cokecl]

How would you do it if you wanted to record the line in to tape?

[@titaniumdiveknife]

MOAR!!!!!!

[@T1ppa]

Nokia stereo set? I haven't seen one before and I'm Finnish :O

[@TheMrJamu]

They were probably sold under the Salora label here in Finland?

[@Djax666]

Hello, from who is the introduction music and what is its title?

[@omidkiani4585]

I have a 3mm mic input on my old boombox which works fine with up to 10% of my pc output volume. How about bypassing the mic amp with some wire and use the port? is it possible? or maybe make an external 1:100 voltage divider as an attenuator and connect input and output jacks to it? what do u think?

[@abebasset7693]

can u put the link u got it from on eBay

[@shivaprasadsapkota8871]

i have Sony mhc GN1000D system which i tried to connect to computer or mobile devices via rca cable but it only sound in one side of speaker .Do you have any idea how can it be resolved?.

[@paradoze]

I don't find the giveaway section on eBay. I live in France, so maybe that's why I can't see it. Does anyone have a link?

[@redboth5722]

i love you boy u r great

[@HelloKittyFanMan]

"...In the year two thousand fourteen." Try saying "TWENTY-fourteen," etc. for 2014, etc., because it's shorter and thus easier, just like it was for years from previous centuries.

[@alexanderchristopher9715]

Is it possible to do this to a car radio?

[@myvideos6391]

How to add Bluetooth in DVD player

[@killercaritas9442]

What if it only has headphone jack no aux how can you add bluetooth?

[@manjirimarathe4428]

How to add line in connection for blaupank Hanover car cassette player ?

[@HDXFH]

Good old Nokia Before they got into the cellphone business

[@aamirhussain000002]

it look like that i give system to shop for installation of blue tooth and i get it done

[@EmpiricalCat]

Kleinanzeigen means classified ads in english :)

[@carlbrutananadilewski3345]

Where do you source the Bluetooth PCB?

[@LostDeadSoul]

www.ebay.co.uk/itm/APT-X-Bluetooth-4-0-Audio-Receiver-Board-Wireless-Stereo-Music-Module-iPhone-PC-/131574530311?hash=item1ea2740107:g:G6AAAOSwpDdVFmyN

[@Rainbow__cookie]

Wow battery not leaked is it Orginal batterys 🤔

[@thewonderfulwizardofozisan7573]

I enjoy your videos! But the signature melody is quite anoying.

[@sangeeth_619]

Surprised to see a Nokia made cassette deck!😲😱

[@parvatkishan3850]

I did that too a year ago!

[@leberkassemmel]

I need that Bluetooth Receiver for my Car. It already has Line-In, so it shouldn't be a big problem.

[@LostDeadSoul]

www.ebay.co.uk/itm/APT-X-Bluetooth-4-0-Audio-Receiver-Board-Wireless-Stereo-Music-Module-iPhone-PC-/131574530311?hash=item1ea2740107:g:G6AAAOSwpDdVFmyN

[@ninjamaster3453]

+Tummas Eivin Kruse how would you implement? BT audio device connects > feeds audio out > 3.5mm to RCA >rca to aux input radio + remove led indicator to place where needed. radio set to aux, BT connect, audio plays anything missing or wrong W this approach?

[@leberkassemmel]

Ninja Master 5 V from the USB Port, and the Audio Wires to the Audio In

[@LostDeadSoul]

That specific bt receiver has a 3,5mm jack on it, so you can connect it straight to your aux input on your car sterio. unless you need rca, i would recommend soldering one end of the cable to the ROUT,LOUT and GND. I use that one in my festival-speaker. It works great. There are two leds on the board, but i never need to look at them. i just see the unit connected to my phone. My BT unit is also glued inside a car-sterio amplifier which is screwed on to a HiFi speaker so i barely see any light from the leds. That unit is also 12v, so it's easier to connect it to the acc. cable coming to your sterio. Just don't put the unit inside any metal box or else your will need an external antenna.

[@leberkassemmel]

Tummas Eivin Kruse I know that the Unit i ordered works on 5V. But luckily my Car has 5V. I am thinking about putting it into the place under the Armrest, as there is enough room to fit it all. And if i need to check something, i can access it really easily