Mega Drive Blank Screen No Sound (Binned)

[terriblefire]

Hey,

I got my son a MegaDrive to play with but i cant get it to power up. I've given it 10V center negative and it draws about 0.7A. The lights come on and there is a 7MHz clock at the 68000. But no sound output and no screen. There is 5v on the board too.

Ideas of what to check? i have Sonic the hedgehog cart in.

[Steve]

There are three models of Megadrive and they all have different motherboards. They have a sony chip that encodes the RGB and audio. But to be honest these things are tanks and usually it is something simple. I would just clean the cartridge contacts with IPA and check the connector doesn't have dry solder joints. I assume you're using SCART, make sure you use a Megadrive compatible one.

[terriblefire]

Actually on RF right now and have headphones in the socket.. i'll post some photos.

[terriblefire]

Photos - Got no idea..

Both regulators give me 5.00v

[cmorley]

Clean the cartridge edge connector on the motherboard and the cartridge. Bad connection to the ROM & you get nothing. I often get this when I insert my megaeverdrive for the first time in ages. As an extension, check the cart soldering for cracked joints.

Have you tried another game in case the cart is dead?

[Steve]

Clean the cartridge edge connector on the motherboard and the cartridge. Bad connection to the ROM & you get nothing. I often get this when I insert my megaeverdrive for the first time in ages. As an extension, check the cart soldering for cracked joints.

Have you tried another game in case the cart is dead?

Yeah try cleaning the cart and edge connector, and check for dry joins. Dunno why I didn't think of that :lol:

[terriblefire]

Tried all of the above. It looks like someone has been at this board already. There were tiny solder balls lodged between the TQFP package pins. but that hasnt helped :/ Trying to decide if its worth removing the 68000 and putting the logic analyser on it

[cmorley]

Trying to decide if its worth removing the 68000 and putting the logic analyser on it

Sub £30 on eBay for a working one with a game or two and 2 controllers... or £10 for just the console.

[terriblefire]

Trying to decide if its worth removing the 68000 and putting the logic analyser on it

Sub £30 on eBay for a working one with a game or two and 2 controllers... or £10 for just the console.

Thats what i did and this is what i got.

[go0se]

Trying to decide if its worth removing the 68000 and putting the logic analyser on it

Could it be that we have just witnessed the first step towards a Terriblefire Megadrive Accelerator? :lol: