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protek
20th September 2012, 12:07
In my project car I have a traditional two knob radio, which works but I'd like to have at least the possibility to play stuff from USB or external MP3 player. I also have an FM transmitter for getting external audio to my current radio but the quality is sub par.

There are modern retro look car stereos that fit into the two knob slot and enable you to play MP3s but those are relatively expensive (150 and up).

I'm looking to spend around 50 at most to get this done as you can get regular DIN CD changer for that price. I know it's not hi-fi but trust me, with dual sport exhaust and minimal noise insulation hi-fi is not what I'm after. Just a decent listenable sound.

Is it possible to tap into the original car radio's amp to feed it with the audio from MP3 player? How do you override the radio on that case as there is no source selector?

Are there cheap and small receiver/amp PCBs available that supports multiple audio sources and would fit inside old car radio? Would it also be possible to control the volume and frequency utilizing the original knobs? This would probably mean some kind of A/D an microcontroller, right?

Justin
20th September 2012, 12:22
we fit a lot of these retro style stereos, they are modern head units put inside old radiomobile style cases. the difficult part is intergrating the old controls with the modern tech.

personally i would go with the prebuilt unit, but then your skillz are probably a lot better than mine:)




In my project car I have a traditional two knob radio, which works but I'd like to have at least the possibility to play stuff from USB or external MP3 player. I also have an FM transmitter for getting external audio to my current radio but the quality is sub par.

There are modern retro look car stereos that fit into the two knob slot and enable you to play MP3s but those are relatively expensive (150 and up).

I'm looking to spend around 50 at most to get this done as you can get regular DIN CD changer for that price. I know it's not hi-fi but trust me, with dual sport exhaust and minimal noise insulation hi-fi is not what I'm after. Just a decent listenable sound.

Is it possible to tap into the original car radio's amp to feed it with the audio from MP3 player? How do you override the radio on that case as there is no source selector?

Are there cheap and small receiver/amp PCBs available that supports multiple audio sources and would fit inside old car radio? Would it also be possible to control the volume and frequency utilizing the original knobs? This would probably mean some kind of A/D an microcontroller, right?

protek
20th September 2012, 12:33
we fit a lot of these retro style stereos, they are modern head units put inside old radiomobile style cases. the difficult part is intergrating the old controls with the modern tech.

personally i would go with the prebuilt unit, but then your skillz are probably a lot better than mine:)


Yes, the question is that is it economically feasible to buy the necessary components and try to fit them inside an old unit or do I just end up paying more?

Cheapest option would probably be that I'd just disconnect the old tuner from the amplifier and just feed it with an external MP3 player that has an integrated radio.

MZ3540
21st September 2012, 01:29
a few years ago I added line in to the am radio in the car I had at the time so I could use my mp3 player.

The volume pot is where you patch the lead in... that's where the am tuner ends and the amplifier starts.

This setup had the signal from the mp3 player amplified by the stock radio and the sound came blasting through the factory single centre dash mounted speaker.
Sound was crap, but was far better than listening to the crap that gets broadcast on am.

I'm a bit fanatical at keeping my cars stock, that's why I did it this way.

Sent from my GT-I9100 using Tapatalk 2

80sFREAK
21st September 2012, 02:54
a few years ago I added line in to the am radio in the car I had at the time so I could use my mp3 player.

The volume pot is where you patch the lead in... that's where the am tuner ends and the amplifier starts.

This setup had the signal from the mp3 player amplified by the stock radio and the sound came blasting through the factory single centre dash mounted speaker.
Sound was crap, but was far better than listening to the crap that gets broadcast on am.

I'm a bit fanatical at keeping my cars stock, that's why I did it this way.

Sent from my GT-I9100 using Tapatalk 2

+1. Did the same with old tape/radio, put "tail" with 3.5mm jack out and controlled sound on mp3 player. Cost to build - 1m of shielded cable(needed only half meter, but shop could not sell less than 1meter) and 3.5mm stereo jack.

MZ3540
21st September 2012, 03:16
controlled sound on mp3 player

Solder the wires across the potentiomer if you want to control the volume with the knob on the radio.

Sent from my GT-I9100 using Tapatalk 2

protek
9th January 2013, 17:43
I ordered a stereo amplifier kit. It outputs 2x5W, which doesn't sound that much but I believe that it is pretty much in level with a '70s car radio. It takes 12 V so It can be connected directly to the car power outlet. I have an old MP3 player but it has only 128 MB of RAM. I wonder, if the RAM chip could be changed to a bigger one? On the other hand, you can get a player that accepts SD cards for peanuts. Wonder how difficult it'll be to put one in parts so that the display and card slot could be separated from the pcb.

bdb
10th January 2013, 03:48
Did you check your power supply and capacitors for leakage?

protek
10th January 2013, 06:17
Did you check your power supply and capacitors for leakage?

Well, the "power supply" aka the car battery had leaked at some point as my car's trunk bottom had practically rusted away and I had to have it replaced. :lol

80sFREAK
10th January 2013, 08:40
I ordered a stereo amplifier kit. It outputs 2x5W, which doesn't sound that much but I believe that it is pretty much in level with a '70s car radio. It takes 12 V so It can be connected directly to the car power outlet. I have an old MP3 player but it has only 128 MB of RAM. I wonder, if the RAM chip could be changed to a bigger one? On the other hand, you can get a player that accepts SD cards for peanuts. Wonder how difficult it'll be to put one in parts so that the display and card slot could be separated from the pcb.
Depends on player, usually display connected via ribbon cable. For SD-card slot use cheap card-reader, just wire it(SD-card slot) to PCB of player.

rkauer
13th January 2013, 04:17
Ghetto solution: put a cheap radio+card reader inside the glove compartment and keep the original radio as decoration.

protek
13th January 2013, 07:49
Ghetto solution: put a cheap radio+card reader inside the glove compartment and keep the original radio as decoration.

But where would I put my gloves then? :lol:

I've thought about that. I've also thought that I'd mod the original radio with an audio input that would switch the signal from the tuner to the external player.

I just thought it might be fun to do a modern stereo that would fit in the old style "two nipple" slot.