TRS-80 Model 100

With the recent talk about nicad batteries, I took a look at the one in my model 100 ... fortunately. I found the nicad just starting to corrode and most likely in another couple of months would have started to spill onto the circuit board. Just mentioning it so any of you who have one or ANY computer that has an internal nicad battery might take a look at it before it does any damage to the computer. While I was trying to find out why the one I had didn't work, it decided that it was time to start working again. Wow, love those intermittent problems. Now, everything seems to be working okay from the processor part, but I have a display problem. The contrast adjustment has no effect, and the display will sometimes change its contrast while I am looking at it or if the main board is mechanically moved. Anyone have any idea what might be causing this? Thanks.