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Background
My dad has a zarzon cocktail table that we used to play as kids and has since sat dormant that I am getting back in order.

link to chassis (Toei C14C-5090) schematic
link to zarzon schematic


Observed Behavior
When turned on, the slow, ramp up/down sound plays, but only sometimes does the main bit of the song play. Sometimes, the ramping sound would come across as choppy. I had to mess with the screen knob on the monitor, but eventually the display shows white with raster lines and a flash every 3/4 of a second where the picture appears to scrunch into a bright vertical line momentarily. The game does not play blind. I measured B+ voltage at 104VDC (+112V nominal).

Steps Taken
I have recapped the game board and the CRT chassis. I was probing around with the oscilloscope on the game board trying to find the sync signal and found the hex inverter 74LS04 (IC4) was shorted and getting hot (though I may have damaged this accidently). I replaced the part and now a sync signal appears at the game board connector output. I bumped up the 5V signal to read 5.14V at the connector when powered on (up from 4.8V). Unloaded I measure 5.45 volts on the original switched supply output. I removed all the socketed chips (except for the ROMs), inspected and cleaned the leads, and replaced them in the sockets.

Next Steps
I was hoping recapping the chassis after I replaced the hex inverter would do the trick, but here I am in the forums. I don't have a way to output a test pattern (that I know of, yet) to test the game and the monitor individually, but I believe I should be starting on the game board; however, I expected if I had a sync that would show something. The BGR signals show 0V on the scope, so I'll probably pull the board and check that out, which seems to be the ROM at IC3. Any better ideas?
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