2 slot not displaying red

[bwi]

Does anyone have any ideas why my 2slot isnt outputting red. I've known the last couple of days there was something not right about the board, but thought it was because i didnt have any resistors on the RGB lines of the scart connector.

But today ive hooked it up to my supergun which has got pots on the RGB lines and when you adjust the Red nothing happens.

Any ideas where to start looking?

bri

 

[channelmaniac]

Check the line from the JAMMA edge connector back to the resistor ladder. If it's cut or burnt fix it.

Next check the 74LS273 chips. One of those may be bad. However, if it was bad you'd miss a little of some of the other colors too.

RJ

 

[bwi]

The trace from the jamma to the resistor is fine, how do i check this chip you mention?

Can you buy these chips?

bri

P.s also when i trace it around the board i lose it when it gets to the hd74Ls05p chip