Repair : C64 Black screen with signal : bare board

So I've been looking for a challenging board on Ebay as it's pretty much the only place available for me to find dead C64's.  They are expensive and in general not difficult to fix.  The board I fixed first up was a really dead Gumtree purchase.

Anyhow on with this new board.

1) The Power on flicker

When I first turned the board on I got the "power on" flicker.  This was a really good sign.
The SID on this board is soldered on the board so I'm pretty hopeful it's working at this point.

2)  Dead Test Cart.

Plugging in the Dead test cart I got the black then white flashing screen.  This is a sure sign that one of the RAM chips is dead.

I felt each chip on the board and one of the RAM chips was boiling so I pulled it and put a known good one in.

On turning the machine back on it was still flashing, this was a sure sign that both RAM chips were dead.

I replaced the second one and straight away I got the Basic screen.

3) Jiffy Dos Dead?

The Jiffy DOS screen only stayed up for 5 seconds, then the cursor stopped flashing and then the screen cleared.  I had a spare kernal on hand ( that I had burnt in a previous project ) so I swapped it in and ever since it has been rock solid.

Finale!

Well that was easy, two ram chips, one kernal rom and everything is working, even the SID.

So I'm thinking I am done with C64's . . .

I'm thinking about trying to pickup some dead Amiga 500's as I'm getting a little bored of easy to fix projects.