Technical Aux input on factory head unit

[somik]

Hi guys, could someone give me some advice, please ? I have a blaupunkt mid factory stereo and i need to add a auxiliary input (mp3 jack). I tried googling around but apparently most factory stereos (including mine) dont support aux input. Is there a way around that ?
I dont really want to buy a new one (and i'd prefer if i didnt need to buy anything at all, i need to finish it asap).

Also, i dont listen to radio, playing the tracks off my mp3 player is pretty much everything i need from my car stereo (i would gladly exchange the radio for mp3 aux input functionality).

Blaupunkt mid has input for cd changer (its the blue mini iso connector), could it be of any use ? I thought about soldering mp3 jack R/L/G channels in the mini iso connector, but then i'd have to make stereo play through cd changer output - and I dont know how. Source button on the stereo only offers radio and tape player (by the way, how about exchanging the tape player for mp3 jack input ? With some wiring/soldering, would that work ?).

One last idea would be soldering wires from mp3 jack straight to rl/rf/lr/lf/g wires but that seems too hardcore and not safe at all.

Thanks for any kind of help guys.

 

[benny279]

probably not the answer you want......
but to save all the faffing around with a factory stereo, that has next to nothing features, go get a cheapy aftermarket stereo that has aux already there for your pleasure! i cant see the logic of modifying a factory stereo just for this purpose im afraid
but if you wish to mod it then go for it but i wouldnt advise it one bit!

 

[PuntoHowTo]

If you have a cassette player why not just buy one of those cassette to 3.5mm jack adaptor things for about £5

 

[somik]

Well, its more about doing it myself, i kinda want to faff in it tbh. I love sticking my nose in wires and I know i would enjoy the audio system a lot more if I modded it instead of just buying a new stereo. Also I couldnt be more broke.
That cassete player is integrated in the stereo. It may work but i think i will have to see inside it.

 

[PuntoHowTo]

Ok well to use the cd changer input you'll need to digitally trick the head unit into thinking there is a cd changer connected this involves serial data interfacing and CDC protocols.

To take the tape player route you'll need to intercept the audio signal between the cassette tape head and the amplifier with a non amplified low gain signal, to avoid clipping of the audio signal. probably best to use oscilloscope to track the signal and plot the amplitude so you can get the gain right.

And because the radio is coded to the car, won't function on a bench without the can signal you'll need to do this all with the radio hanging in bits out of the dash of the car....

Or....

You could buy a £5 cassette adaptor, and that's coming from a well trained seasoned electronics engineer. At least then you can take some time to decide if you want to go further

 

[somik]

Thanks Andy, it didnt make me happy but that was the kind of answer i was hoping for.
I'll definitely look into that cassete adaptor, but before that, how silly would be simply soldering jack into the rear/front speaker wiring ? I suppose these speakers use traditional L/R/G channels. You see i have a car subwoofer that i'll be installing soon and i can only use rca or jack to connect it to audio source. That means i only miss speakers in my audio setup. I wouldnt need the blaupunkt stereo at all, would be ideal.

 

[oldhammer]

Your best way is just to buy a wired FM modulator.
I had a vibe one it was pretty good.

 

[somik]

FM modulator, sounds interesting.

 

[somik]

Okay i found the wiring scheme on the stereo and I know where wires to speakers go. Is joining front and back speakers with jack a bad idea ?

 

[oldhammer]

Okay i found the wiring scheme on the stereo and I know where wires to speakers go. Is joining front and back speakers with jack a bad idea ?

It won't work like that mate.


Just grab a modulator, wire it up to 12v-plug. It into the airiel tune into a spare unused radio station' and then you can plug in what ever you want its less hastle.

You can get FM transmitter thatl plug in the ciggy lighter/plug n play jobbies
But they can be fuzzy..

Just try in to give you some ideas mate n save you some messing,

 

[oldhammer]

Sorry your thread is confusing.

Seems to be two different topics'

Are you thinking of just running a amp and sub with line in for MP3 or what ever and
Not using the radio..

If so you might need a speaker to r.c.a convertor.

Maplins/eBay/Amazon etc sell them cheap as chips

 

[somik]

i have some rca cables and mp3 jacks, ill solder some convertors if needed. What started to bother me right now is whether or not im gonna need additional amplifier for the speakers. I think i will find out really soon.

 

[oldhammer]

Yeah it will be needed to be amped mate,
Or you will end up with low/volume. If you get what I mean,

Not unless this sub your planning on fitting is the type with built in amp,

 

[somik]

yup, its a 400w amp, and wiring those speakers to it is a magnificent idea. I just need to get myself some proper thick wires, and use my old volume controller but other than that it sounds excellent. Thanks.

 

[jmckee4]

OP, have you seen this link?
https://www.fiatforum.com/punto-guides/320274-upgrade-punto-188-cassete-radio.html

Alternatively, if its a mk2 stereo, you can buy an iso block to 3.5mm jack cable (just search ebay for punto aux cable) and use the src trick. See here:
https://www.fiatforum.com/punto-ii/314776-aux-mk2b.html?p=3143224