Hey guys,
I've been building my sammich kit over the last few days and it's been smooth sailing up to the part where the LCD screen failed.
At first it was dim and the contrast was horrible (I could just make out the word "Ready"). I tripple checked the Jumper settings and joined boards once again.
After turning the power back on I saw the backlight get very bright and then a small pop and the light went out. This was accompanied with the smell of something getting burnt out. Not to sure where the source of smoke came from but I could smell it stronger around T1, P1 and the resistors behind it.
I turn it off, unplugged it and went looking for any possible signs of damage but couldn't see any.
PSU that I'm using is the regulated 12V DC Powertech, switchmode from Jaycar. Cat No: MP3242.
LCD screen was the one supplied by Wilba. One thing that has puzzled me is the LCD has written on it 5V.
I'm going to be using 6581's and the Jumper configs are as follows: Jumper on 12v for backlight with jumper on JR4, SID jumper on for 6581 and both jumpers on JBP.
I made all voltage checks and all were correct, but I was getting a 12.1V reading on the 12V points which I didn't think was enough to cause an issue.
Also the Trimpot P1 was set at the 12 o'clock position when the LCD screen went out.
Would appreciate any suggestions.
EDIT: From my understanding the supplied LCD is a 5V and I positioned the jumpers to supply 12V. So I've given it 7V too much and cooked it.
Cheers,
Marty.