Master System:Audio Line Out Mod

ApolloBoy

• • SMS Audio A/V Pins**

This page shows you how to get audio directly from the SMS A/V port.  This would most commonly be used for routing audio through the NEO Sega MKiii ROM cart, which adds FM audio to your SMS.

\- First, start by completely disassembling the Sega Master System (all that's needed is a phillips head screwdriver).

\- Next, take a standard RCA cable, strip the end and run it through the bottom plastic of the SMS system, in the same spot the A/V connector would be.  I prefer to tie the cable on the inside of the plastic, so there's no chance of it accidentally pulling out:

\- Then, flip the SMS main board over and line it up with the rear cover (detailed pic of solder points is next):

\- Place a piece of non-conductive tape underneath the area where you'll be soldering.  Then, solder the following points on the board.  Mono audio is on the left, ground is on the right:

\- Re-assemble the system:

\- I suggest putting a piece of non-conductive tape over the area you just soldered, to prevent it from touching the metal shield. 

\- Tuck the excess audio wire underneath the metal shield plate. 

\- Make sure the knot is properly snugged against the case:

\- All done!  If you're using the Neo Sega MKiii, plug the new audio cable into the "SMS AUDIO IN" port as shown here:

\- Run an RCA audio cable from the "FM AUDIO OUT" port of the Neo Sega MKiii into the audio input of your device.

\- If you're using an RGB cable and your device doesn't have a separate audio input, you can wire the mono audio line to both pins 2 and 6 on the SCART connector, then audio ground to pin 4:

Please [fmaudio.html click here] to go back to the FM Sound page, or [sms.html click here] to go to the main SMS page.