RGB SCART cable + Megadrive 1 + 32X

[JDAdams]

Hi,

Having located an RGB SCART cable for the bargain price of £9.99 (well, I think it's a bargain), I can't seem to get the sound working. I get a loud buzzing noise on both channels, which gets louder the brighter the picture.

I *do* get the sound, but the buzz is much louder and very annoying.

Is this something to do with the Megadrive 1 only putputting mono sound? The buzzing occurs whether I use the Megadrive alone or with a Mega-CD and 32X, is unaffected by connecting the MD/MCD audio passthrough cable, and is not present on the Mega-CD's RCA outputs.

My last RGB cable worked, but my brother broke the blue pin🙁

 

[Mike G]

The MD1 was never the quietest beast in the world, and you'll always get a slight buzz no matter what you do with it.

If the buzz is a lot louder than normal though, it's usually due to poor shielding or a or dodgy Ground connection.

Why not make your own cable? Go to Maplins: 1x FG40T, 1x FJ41U, 3x M75R, 1x M100R, a couple of metres of XS42V. That's a lot less than £9.99 😉 Follow the diagram here and you're sorted:

http://www.mikeg2.freeserve.co.uk/masterful/scart.gif

Mike

 

[JDAdams]

Having already bought the cable, I don't really want to have to build another one (I guess I could put it on eBay - the last I checked the only one on there was going for £25), but thanks for the info.

I've tried wiring the audio ground pin directly to the SCART casing, and that didn't help at all (the buzzing is still about twice as loud as the actual audio) - could the lack of grounding on pin 17 be affecting the sound somehow?

P.S. the buzzing persists if I use composite video through the same SCART lead but my TV's other SCART socket

 

[JDAdams]

RIght, I've now wired pins 4, 17 and 21 together, and the noise is still there. The picture is fine, though - why is there no visual noise if the ground wire itself is suspect?

 

[maidtina]

Just sounds like they used shite cable to make your lead. Not enough shielding and your getting crosstalk from the composite video feeds in the sound lead. I would suggest building another one with the heaviest shielded multicore you can find. Use a sledgehammer/walnut approach is my motto 🙂

 

[JDAdams]

I already found a solution, thanks - I bought a 5-way SCART adaptor (I wanted one anyway). I just plug the RGB lead into one socket, the stereo RCA leads fom the MCD into another (via a SCART adaptor, obviously) , and use the output for my TV. The MCDS' audio is far louder than the RGB cable's audio or the annoying noise, so I didn't even have to cut any of the wires😀