Thread: Relay and custom cable recommendation.

+1

I am interested in building a 24 conductor harness for between the screen/usb hub and the computer in the trunk. Any suggestions for good connectors and cables?

I know that the stock wiring in the car has different color stripes on the wires, something like that would be great.

I am adding an AUX connection to my factory radio.


This is what I plan to do:

www.mbca.org/northtexas/audio_systems.htm

I want to replace the switch in this schematic with a relay.
When the Sirius radio is on, the ground acts as a power source for the relay, closing the relay and switching audio sources from the CD changer (in the trunk) to the Sirius radio's LINE OUT.

Can I use the GND from my external Sirius unit to switch audio sorces from my factory CD changer by activating a relay rather than use a switch?


Thanks

I don't recall any External Sirius units that 'show' ground when they're turned on.. but if you have one, then yes.

As for power and audio with Cat5/6, I run a 50' Cat5e with 12v DC, video and audio to an LCD I have hanging in my bathroom with no problems. Granted this is in the house and not as likely to pick up interference as stuff in the car..

Well...maybe we are talking about the same thing different ways.
When the power comes into the satellite radio, it then leaves by the ground wire. This ground wire, if taken to ground is just that. Otherwise it is actually +12vdc, the same that is going into the satellite radio, which can then go on to power other things.

If the satellite radio is turned off, the relay would go to the default position (call that position 1) where the relay then completes the CD changer circuit. When the satellite radio is on, the power exiting the radio (that would normally go to ground) goes to the relay, the relay then goes to position 2, opening the circuit from the CD changer and closing the circuit for the satellite radio's audio stream. All the circuit does is break the audio stream.

Now...putting the relay on the signal side (using a dpst switch) to open the appropriate circuit may bring noise into the circuit.

Looking at the drawing on the web page, , shows breaking the audio. What would happen if the audio shield side was the side that was switched? Since that is post-amplifier (and post-speaker) would that eliminate the noise (assuming you agree with the power-switched relay concept above.)