Aux audio in instructions.

[Britprius]

As a follow up to my post on a high quality audio input for the pre-2008 GS, and possibly others here are the instructions circuit diagram, and pictures so far.

The screened cable can be accessed and cut in any one of three places. Each end of the cut is the extended with screened cable to wherever you wish to put the single hole mount switched single channel jack socket. Maplins part number HF82D. A stereo socket "2 channel can be used if you wish.

The places to access the cable are:-

(1) Behind the radio unit a black cable going into a square blue plug. If you can obtain a suitable plug and socket the cable need not be cut.

(2) In the boot on the drivers side under the small floor panel. Again a black wire going into a blue plug. This plug is the rear most plug on the amp.

(3) The black cable runs under the capping on the drivers door sill. It could be cut here and the extension wires run under the carpet into the centre arm rest. Possibly easier than removing the radio or running wires to the boot.

The unit needs a 5 volt supply. I used a cigarette lighter phone charger adapter in the centre arm rest. This has the advantage that it is turned off when the car is not in use, but works in the accessory modes. All required leads were supplied with the converter except the extension screened wires.

Circuit diagram, and pictures of the unit. The unit is approx 2.5 x 2 x 1 inches. The unit MUST be an A to D converter. I will add a picture of the amp blue plug as soon as I can.

To operate there must be a CD in the player, and that CD set to play. Plugging the jack plug into the socket will automatically switch off the CD sound and play any audio input. All OEM controls work including the graphic equaliser, and steering volume.

John.

 

[Britprius]

To add to the versatility of the the above aux input I have now made up a small Bluetooth adapter to add to it.

It is based on a circuit board from a cheap Bluetooth headphones set from Aldi. The sound quality is excellent with deep rich base that rumbles through your body at even medium volumes. Although not difficult it does require good soldering skills on a printed circuit board about the size of a five pence piece.

A larger unit could be made from again an Aldi Bluetooth speak making the circuit board easier to handle being somewhat larger.

If there is interest I will put up instructions.

John  

[Farqui]

Nice one John, the wireless option should prove very useful.

Soldering on a PCB the size of 5p sounds grim, so well done.

[Upex]

I'd be interested in instructions John, for the wireless adaptation, hate cables in car.

Will check out the above, as at first glance, can't figure out what the wires are that form the squares at the cut Mark.

Also, you say if can find a plug, the plug wire wouldn't need to be cut. Can you elaborate, as id be keen to build something more complex etc, if can save cutting original cable.

Think I'd head to the boot, getting the head unit out looks like a real pain to do without marking anything.

Ps, thanks for calling out this thread. Hadn't seen it, but very glad I did. Now if only you could figure out a full solution of charge, audio and display input over usb c, you'd be a very popular (even more so) chap 😁 

Thanks

[Upex]

Are the cables which need cutting optical? Been doing some digging and everything says the head unit to amp cable is optical, unless this si on later models?

If it's optical, I'm wondering how these are spliced, whilst retaining the quality (ie alignment of the optic cable) as any misalignment would cause loss of sound.

[Britprius]

Robert.

The connections are electrical not optical, "I have the system up, and running on my car (2007). Even if they were optical the unit is capable of an optical input. So all that would be required is an optical "T" piece at the back of the head unit or at the amp to configure the optical input.

I have configure my wiring by unplugging the cable from the head unit, and manufacturing a plug and socket to extend the required connections without cutting any wires.

John.

[Upex]

Don't suppose you have a spare plug John? Or know what type is needed? Not keen on cutting, but happy to run to head unit or amp.

Be interested in how this could be Bluetooth to. Assume the converter would just be a different one that does Bluetooth?

Cheers,

[Britprius]

On 10/29/2017 at 6:46 PM, Upex said:

Don't suppose you have a spare plug John? Or know what type is needed? Not keen on cutting, but happy to run to head unit or amp.

Be interested in how this could be Bluetooth to. Assume the converter would just be a different one that does Bluetooth?

Cheers,

Robert it is quite easy to make suitable plug, and sockets.

 The socket on the rear of the head unit "once the blue plug is removed" consists of a single centre pin, and a surround ground connection. This is the digital signal out. A thin plastic tube "think biro ink refill" with a piece of wire pushed through should push tightly onto this pin. The ground wire (outer screen) can be connected on to any handy screw on the back of the unit.

The blue plug removed with cable going to the amp in the boot has a single centre small hole that a piece of stiff wire or paper clip will push firmly into. This is digital signal wire. If you ground the outer screen of your connecting wire where it comes out of the back of the jack socket there is no need to connect the screen at the blue plug as it is grounded at the amp end.

I have found a small Bluetooth device that will plug straight in to the jack socket to enable the system to be converted to Bluetooth  on eBay for the grand sum of £2-98 including delivery.

Item number

172841358360

John.

 

[Upex]

Nice one, thanks John. Will do some thinking and see what want to do.

Thanks as always.