Modifying AES AV port for stereo

M

max-ng

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Being in the UK I use RGB through the AV port and at present a separate lead off the scart to the headphone socket for the stereo output. I don't need composite and would like to route the stereo through the AV socket. No problem with picking up the stereo feeds on the board but can anyone give me some pointers to taking this to the AV socket on the back? Presuming the socket is soldered direct to the PCB - where to cut the composite etc.

Thanks!
 
norton9478

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Make sure that you don't need composite... Some cables run the sync to the composite output.
 
M

max-ng

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Thanks for that - good point as according to the pin out on gamesx the composite should go to pin 3 and sync to pin 7. However, on my AES's RGB lead (which works perfectly) the NG pin 7 is not connected and pin 3 must be the sync. Presuming then that it is OK to use the NG pin 1 (normally mono) for left stereo channel and pin 7 for right stereo channel?
 
Xian Xi

Xian Xi

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Yes correct. The sync comes from pin 3 via composite so you can use pin 7 for audio right.
 
Kid Panda

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I hate to bump this thread, but I was just thinking about this today. So where would I tap the audio right from?
 
shadowkn55

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kidpanda said:
I hate to bump this thread, but I was just thinking about this today. So where would I tap the audio right from?
Click to expand...

I would tap both the left and right audio signals from the headphone area. You should disconnect the mono audio coming from the encoder by removing the capacitor (10uf) and resistor (10k) leading out from it. You should probably also disconnect composite sync. That part varies depending on the version mobo you have.
 
Xian Xi

Xian Xi

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shadowkn55 said:
You should probably also disconnect composite sync. That part varies depending on the version mobo you have.
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Yes, it varies from revision. If your board is a 3-5 or 3-6 then composite video will be going to both pin 3 and 7. You can cut some traces under the AV port to disconnect the video to Pin 7. For anything earlier they are on separate pins sync on 7 and video on 3.
 
shadowkn55

shadowkn55

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Xian Xi said:
Yes, it varies from revision. If your board is a 3-5 or 3-6 then composite video will be going to both pin 3 and 7. You can cut some traces under the AV port to disconnect the video to Pin 7. For anything earlier they are on separate pins sync on 7 and video on 3.
Click to expand...

I think what I did for those was remove 1 or 2 of the ferrite beads and then jumper composite video back into pin 3.
 
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