How to Add a Line-In and Bluetooth to old Stereo Systems (2)

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First Video in the series:
• How to Add a Line-In a...
Videos about Isolation Transformers:
• The Power Grid, Isolat...
and
• Isolation Transformers...

[@brandonsaffell4100]

Thank you for making this video. Seeing the actual points where you soldered the line in and switches was very helpful in understanding the overall concept.

[@woodlandor]

The switch type over here is called a: "Double Pole, Double Throw" Great video as usual, keep up the great work!

[@gregbenwell6173]

I was just about to say the same thing or in the "industry" we call them DPDT Switches which is an abbreviation of the same thing, "Double Pole, Double Throw"!!!

[@ronniepirtlejr2606]

He's got the translation correct but of course they have a different name in the industry here.

[@HelloKittyFanMan]

For future reference (in case it hasn't already been answered in the last 7 years), that first kind of switch that you added is called a DPST switch: a double-pole, single-throw switch.

[@danajohnson3799]

Slight correction: You scraped off the solder mask not the silk screen on the bottom layer of the board under the chip to solder your ground wire. From your diagram, in English, we call the installed switch a Double pole double throw normally open lever actuated switch. Interesting hack, thank you for your entertaining videos.

[@snppls]

Thank you so much. I don't really have any electronics experience but I was able to add aux input to an old HIFI system I had because of your instructions. Much appreciated!

[@georgelewisray]

Great to watch over the virtual shoulder of a person (you) with such great powers of visualization & analysis. Feels like I am not only watching someone 'fish' but I am also learning to 'fish'. ( fish => Figureout Interesting Superduper Hacks )

[@BuckCalabro]

Nice! I half expected to hear Peter Schilling coming out of those old speakers :-)

[@leons6906]

I soldered an audio cable to the pins of the radio on the source selector switch, it was the easiest solution for my stereo. it works great!

[@jamestom2510]

The switch is called a double pole or double throw switch, im sure others have mentioned it here too . Great Hack. For me, i dont do the hack unless it alsready has a AUX in, that way i can hack straight in, Secondly I pick a low voltage clean power source that is running constantly, that way i dont have to wait to connect with my bluetooth phone every time i switch between sources. Yes its running all the time, but only when power is connected. If the unit doesnt have a AUX input i dont touch it. also if the bluetooth led on the circuit board allows a seconday LED i usually mount it somewhere on the face of the stereo or next to an existing LED, that way you know its running and ready to be used. Theis channel is fantastic.... Great hacks.. 10/10 my friend.

[@titaniumdiveknife]

8:19 Always loved that part best. Nice electronics get broseph.

[@HelloKittyFanMan]

"And I'll also scrape off some of the silkscreen..." What you scraped off at that moment was actually solder mask instead.

[@OzmoMac]

cool love that you do videos quite often keep it going :)

[@dozerjohn]

I still want that synth tune of yours, don't think that I'll give up!

[@God-CDXX]

make your own like the rest of us it is just a medi file

[@MrKaizerWEM]

I just got myself a similar stereo and I'm doing the same modification. I've got sound, but the volume is quite low, even with my phone's volume turned up and the stereo volume on max. Any suggestion why that is?

[@abeleballestri612]

Very nice work hope to see you again soon.thank you for the very tutorial video.

[@ronniepirtlejr2606]

I have a 1975 or 76 Panasonic. Model re-7345. Someone cut the power cord and threw it in the dumpster in pristine condition...... why? I disassembled it, inspecting it closely for some skid marks, expecting maybe, it let the magic smoke out ?... nope! I put a new cord on it, then cleaned all the switches & pots. I plugged it in with a current limited bulb & it came on with no problems! I don't get it, nothing was wrong with it? It only has am/fm radio with a phono input. so im I'm trying to figure out how to go about placing a Bluetooth into it without changing how it looks.

[@faithless8888]

Nice!! I was looking fot the solution to not having to press play on the tape deck again! this is genius!!! Thank you!

[@jo31b]

6:40 2 normally closed and 2 normally open is how you would say 2 opening and 2 closing contacts. Double pole double throw would imply only 2 switches.

[@kraftybeard4272]

Great information as always, keep up the good work :)

[@ventiladordesuco]

great video, it is exactly what i was looking for, i scored a sony cmt gpz7 from a local church bazaar here in são paulo for about 10 dollars and it had only a blown fuse, i could found a remote on the internet and a bluetooth device that looks simmilar to yours, it is usb powered and it has a line out only, i was thinking to look for a stable 5v inside the stereo case but only could find some 4v and 3.3v, should I look for a 9v and then use a voltage regulator or something along this lines or the 4v may work? the bluetooth device is powered by a rda 5851SA and i think it has it's own regulator to step down the 5v from usb. i just checked its datasheet and it is a shame that this chip is only being used like a bluetooth receiver as it can do so much more, like drive lcds, PWM, line in, FM tuner, SD card reader, this beast could power a stereo system itself... anyways, how to deal with the bluetooth antenna which is a net on the PCB inside the metal case of the device?

[@TakasuFeNiX]

So... the cassette motor runs always? even if I don't push the play button?

[@killerlawnmower503]

Thank you so much, i did have a AN7316 on my Hitachi cx200 boombox

[@scaleop4]

nicely done...if i have a hi fi lying around i prefer it have a line in as it makes it more usefull that way.

[@randomweirdyoutubechannel8955]

i dont mind pressing the play button but the cassette drives dont work on mine ao would it make sense to unplug the motors on mine?

[@gamerdude0]

thanks for this, i got as far injecting the audio signal but could not figure out to disable the tape signal path and to not have the tape playing. I can finish my project now.

[@sukhdeepsingh5518]

I tried alot to find out where to connect the line in cables, but i failed. I found the preamplifier aswell but still no success. Can you please help me with this.?

[@arielbertinatti2791]

mi equipo lleva el integrado AN7323 y no encuentro el datasheet...

[@ventiladordesuco]

i think it is a DPDT achronym for double pole double throw, sometimes i'ts called dual instead of double

[@Mr.Unacceptable]

If you get a BT transmitter and receiver you don't have to do any of this. Just plug it into the BT device. Either the speakers or line out. This is how an old stereo plays the audio from my tablet in the bathroom. Also a set of PC speakers in the Kitchen. I can Broadcast to and from either setup. Single detent, Dual pole switch.

[@siddharthbarpujari3464]

Can please tell how to detach the speakers? I am trying hard but I'm not able to do! Please!!!

[@coondogtheman]

I'm doing this with an old emerson cd tape stereo I've had for years. im going to use the line in connection from the CD player which is missing (died) and im going to add USB charging as well. I have the guts from a USB wall charger that ill see if I get 5 volts from it since its the secondary DC side. the top is open due to the missing CD player so I'll add a cover or something.

[@jayhill2193]

Can you also make a video about inserting a clinch output?

[@bborkzilla]

I like the chunky switch with its very authoritative "click!"

[@AverageJoe2020]

HaHa, 'Are you German?'

[@ThomasGuaman-bl8ti]

Hey is there some way I could ask some questions? I’ve got a very similar era radio as yours and the Bluetooth receiver I have is similar but I’m looking for how to do what you’ve done with a 3.5 aux instead of line in. Thanks so much and for the already great and helpful video!

[@nosafetyswitch9378]

Amazing as always

[@TheMattfell]

great video, just one thought on it though, a before and after top view of the work you did would be useful, as sometimes when you are soldering we cant quite see what you are doing, i know you do a diagram, but sometimes its just nice to see it in real life. Awesome channel though, reuse as much as you can.

[@HelloKittyFanMan]

Great! But what I'd like to see is how to do it so that you don't even need the first one of those two new switches, because some devices have a "tape/aux." position on that input selector, so that means that the devices that don't have the "aux" side should just be able to parallel with the tape side just like those that do have the feature already. Right?

[@muh1h1]

what you scraped away was not the silkscreen bit the solder resist :)

[@continental_drift]

Switch is called Double Pole Double throw (DPDT)

[@Mathozi]

How can i do it on my philps DVD

[@RzAn8]

you'll find often this designation on switches NO and NC NO normally open NC normally closed

[@PrincessZoey]

what about a stero unit that only has CD and radio function can we hack into the CD path or do you need what the tape deck uses because its analog?

[@edgeeffect]

The CD amp circuitry is probably almost identical to the cassette.

[@edgeeffect]

I like these "zweimal auf / zweimal aus" switches... I thought they were "double-pole, double-throw" But they seem to be better and different. I suppose it's a bit like a "Double Pole / Double Throw"

[@ThePostApocalypticInventor]

Part 3 is now online: kzbin.info/www/bejne/ZmKpYpqhg8qmd7c

[@JTimon]

The Post Apocalyptic Inventor

[@emilio6425]

what did you solder at 3:25 ? Its something off the pin 5(pre-amp out), but I cant see it and I dont think you mentioned it.

[@emilio6425]

Nevermind, I think I see. They are two resistor leads that are connected to the same node already. You simply created a larger contact to connect your audio lines to.

[@upulranaweera3597]

This is a rare video and useful. Could you also do a video on how to add a Line Out? I have come across a lot of stereos that have Line In but no Line Out. Thanks.

[@KIREMS]

first try. when i sellect the tape i get incredibly anoying whine

[@Therapor]

very good work!

[@zx8401ztv]

A Triple pole, Double throw switch or relay would be my discription :-)

[@obsoleteprofessor2034]

Double make/Double break(?).. on editing my first posting.. One can also have a center position where both circuits would be off. I don't know what that would be called.. or how to diagram it here: " = : = " might convey my thoughts.

[@l3p3]

Ja! Wieder ein Video von G.!

[@gilbertsedo]

So practical.

[@STRATOS13PAO]

i think those switches could be called 2 normally open and 2 normally closed, maybe that isnt the term you where looking for though, cause im pretty sure you would know that term.

[@ndog37]

Very nice

[@aleksandersats9577]

i use to have one of the big radios with cassete players but my parents trowed it away before i didnt even had a chance to ask them if i can have it

[@snbhmmz]

ohh thanks god that u back to electronic XD

[@lupolafenice97]

where do i put the gnd of my signal ?

[@lupolafenice97]

can anyone help me ?

[@OldSkoolF]

Multi Pole switch. Wiha.... Nice!

[@jusb1066]

DPDT switch i think is the english version of it, you will see it has 6 connectors, easy to find on ebay

[@michaeltempsch5282]

Not quite - a double pole double throw has two separate switches, each with 1 common terminal that is connected to one of two terminals, depending on switch position, , one normally open and one normally closed. The switch in the video appears to have 4 poles, each single throw, of which 2 are NO and 2 NC. You could wire it to act like a DPDT, by connecting one side of one NC and one NO switch together, creating the common terminal. Repeat for the remaining NC and NO switches to create the second pole. But it looks like he uses 3 separate poles, 2 for audio and 1 for turning on the amp, so a 6 terminal DPDT switch couldn't do the same thing, as it only has 2 poles

[@Ogma3bandcamp]

Winner winner schnitzel dinner.

[@God-CDXX]

his switch has 8 connectors he has a duel nc duel no switch this type does not have any common points you can use a 3PDT where p1 left p2 right p3 power

[@RPBCACUEAIIBH]

As far as I know DPDT = Double Pole Double Throw, where the Pole marks the number of switches inside that are operated simultaneously, the throw marks the number of positions...

[@RPBCACUEAIIBH]

Same marking goes for relays too...

[@krokok.977]

Der Kassettenmotor dreht sich aber immernoch, wenn man den Schalter betätigt, diesen hätte man am besten auch über den Schalter getrennt. The tape motor is still spinning when the selector is used, you better also switch off the motor via the switch.

[@breth8159]

fun stuff :) seems to me you could have found the larger switch ;)

[@tamastorontali3339]

Great video, nice electronic work. Unfortunately the appearance of the front pannel by the switch is crappy.

[@aristoculo9939]

haha you would see others circuit bendings and enjoy real crappy machines

[@maletil]

Thanks

[@ExStaticBass]

The american version of that switch is "Dual position, Dual throw." or DPDT for short.

[@carbonatom6838]

double pole, double throw is the English version.

[@aristoculo9939]

its not doble pole. there are 4 poles in his rare switch, two normally open and two normally close

[@bearbin]

Maybe the switch would be a 2PNC2PNOST ?

@7:48 - whoa that wire guage is fat yo. lol - literally speaker cable !

[@lucitasuarez376]

So many switches to choose for an awkward to the unit

[@HelloKittyFanMan]

"Overview over..."? Or just "overview OF...," maybe, right?

[@EfstathiosOuranitsas]

HI i have a question and i think you are the person to ask and get a reliable answer. i rebuilded a cheap cordlles drill battery form ni-cd too lithium batteries witch i got from an old laptop battery. from 18v with ni-cd i putted 5x 4.5v batteries lithium the brand was samsung green ones and i think they are 2500mAh anyway it works fine and its stronger than very expensive and famous brands. the problem i have is how i should charge them properly since they are all connected together and they produce near 22v and i am not able to charge them with an xtar charger i have for those kind of batteries can u recomend me something not very expensive or a solution ? thanks

[@God-CDXX]

get a transformer that pits 18 v ac and rectify it to dc you will get about 24 volt dc that worked for me will post a circuit

[@bernardbernardin5187]

What I have done for a similar configuration, 3 cells to power a hacked halogen->led flashlight, is to buy 3xTP4056 based chargers on ebay, dirt cheap and measured ok between 4.10V and 4.15V. They are powered from 3 smartphone-type 5V isolated plugpacks. The connector between the charging box and the flashlight has of course 6 pins, a reused PCB-type one (same pin size than the breadboard).

[@EfstathiosOuranitsas]

thanks for the respond but i don't quite follow u really can u explain it a bit more?

[@bernardbernardin5187]

The problem is to charge each cell properly : first constant current then finish at constant voltage, usually 4.2V, or less if you want better cell longevity. With only one charger of 5x4.2V=21V you will have cells under 4.2V and cells above, wich is not good. Because of that I use one charger per cell. And as I want my 3 cells in series to charge simultaneously, the chargers needs to be floating voltage (no common ground), hence the isolated 5V plugpacks (chargers needs 5V input) and the 6 wires of the connector : 1 positive and 1 negative for each charger/cell link. I made a box wich contain the plugpacks and the chargers, it has 230V ac input and a 6 wire connector to bring the chargers output directly to the 3 flashlight cells. I think you can do the same : buy 5 chargers for around 5$, and reuse 5 USB phone chargers to power them (micro-usb port is included) then find a 10 pin connector to link the cordless battery to your charging system.

[@EfstathiosOuranitsas]

THANKS MAN!

[@SteveTVP]

I couldn't find a pre-amp on my stereo system, only a power amp. Now I understand why I did shit and ruined the source of sound I was using to test this. I did got sound when I connected on the IN pins of the power amp, but made the mistake to try on the OUT pins (just like you did). Never use the power amp OUTs!!

[@silasmarner7586]

DPST "double pole" "single throw".

[@aleksandersats9577]

well i just liked the number to 21 yay!

[@titaniumdiveknife]

Sauerland!!!! Oooooh oooooh oooooh oooooh Sauerland!!!!

[@markaz2kk]

we call it double pole, double throw 'dpdt'

[@aristoculo9939]

hahaha too many people saying it is a DPDT but it is not. her rare switch has 4 poles, two normally closed and two normally open. take a good look and don't be smarties

[@Seegalgalguntijak]

I totally would have watched this as one 30 or 40 minute long video. On the other hand, I don't really like cliffhangers...I always think "Oh Mann, mach's nicht so spannend!" ;)

[@parvatkishan3850]

Or you can just connect the audio output wires directly to the magnetic tape reader!!

[@t33s]

And get crappy sound.

[@parvatkishan3850]

+t33s And that's how the story unfolds😂

[@1blisslife]

Radios... it's what Nokia made before candy bar phones!

[@steveone]

Its called a "dual pole dual throw" switch .

[@BEdmonson85]

Actually it's a quad pole single throw switch (4PST). 2 normally open (NO), 2 normally closed (NC) Edit: added acronyms commonly found on schematics in parentheses.

[@BEdmonson85]

+Barry Manilowa Yeah, I used to pretty often as well. It can be confusing.

[@Schnabeltier7I4]

warte immer noch auf die Fortsetzung der Drehbank und der sandstrahlkabine. anfangs klang es so dass du das nicht fortführen könntest aufgrund anderer wichtiger Dinge, Bei jetzt scheinst du daran kein Interesse mehr zu haben

[@HDXFH]

cassette motor runs unnecessarily lol

Line in good...bluetooth suck.

[@PetruV]

It's a poor quality boombox,If the transformer is smaller than a fist,don't even bother.

[@kristina80ification]

Get a better old stereo system that already has a line in , there, one of your problems are already solved. Good quality ones aren't even very expensive if you look at thrift stores and yard sales. Aesthetically or not, there is no reason to use one of these very bad quality stereo systems.

[@l3p3]

I think you missed the point of that channel.

[@t33s]

What if you want a free stereo system for your garage and a boombox sounds good enough for that application?

[@thersten]

I agree. it's like using rotten wood to make furniture.

[@diogosoaresmendes]

Farstt!!

[@niteexplorer9934]

Thanks

[@recordonline]

Thanks

[@diogosoaresmendes]

My pleasure. Maybe we meet again tomorrow?! :) *

[@diogosoaresmendes]

@TPAI: Great videos BTW!

[@AwwwPishhh]

WERA