UPDATE!!!!!
My buddy Darryl (dphirschler) and I spent some time with the Frogger cocktail cabinet this weekend and made great progress!
We managed to get both the service door and the coin door open and only had to break one lock. Of course, I have to replace them both because I don't have keys for either. When we got the coin box out I found a variety of keys and a lock (none of them fit each other) and a total of $7.50 in quarters!
Given this winfall, this brings my total paid for this working Frogger cocktail cabinet with monitor issues to.... please don't cry... $32.50!
No, I didn't miss a decimal point there folks. I paid $40 for the thing!
Our next task was to work on the monitor. We blew out some dust around the boards and found several controls on the main board:
White Gain, Blue Gain, Red Gain, and Green Gain. We first pumped the White Gain all the way up, but it made little improvement. Next we turned up the blue, red, and green gain pots about a quarter turn. We fired it back up and BINGO! The monitor was now playable. It still has several issues, but it is playable. The water is black, not blue, and the blue is missing from the title screen. Also some of the title words are multicolored. I've got a thread on the monitor forum to help identify the monitor.
We knocked out a few games and it played pretty well. The game is slightly cut off on the left and right, but I was just thrilled that it was playable.
We are convinced that this cabinet was probably some other Sega cabinet that was converted to Frogger. I took some pics, but can't post them yet. I'll get them on asap.
Any advice or comments are welcome!
Thanks,
Todd
PS - Thanks again for the the time DPH!