I just shotgunned all the socketed ICs on my Sharpshooter MPU2 board, including a socket at U26 due to tarnished pins on the ROM. I also cut and jumpered the board for 2716s as per instructions online here and pinwik. Alsi replaced Q4 in the reset section.i. I'm pretty new to board work, but have bought decent soldering /desoldering equipment and the work came out well. The board still give Zero LED flashes when installed, but now the Z80 CPU gets hot! So either A- something I did is causing the Z80 to get hot, or B- the old Z80 also ran hot until it blew and the new chip is doing the same....I haven't swapped the old chip back in yet to see.

So I forgot to ask questions!. I'm thinking of shotgunning all the caps on the board. Could a shorted cap cause this hot CPU? I am seeing about 3.5 v at TP4, I have the other 3 transistors for the reset section I was planning to swap in too.

So I swapped the Z80 CPU back in to check my work and as I was running up the stairs, to the game I tripped , spilling homebrew all over the MPU. After drying it off I plugged it in to test it . No flashed from the LED. But then..... it started flashing playfield lights! THE DAMN LED WAS BAD! pushed the credit button and started a game!. Now, there's still a long way to go, no life from most of the solenoids, bad connector corrosion, but it's all curable now. Homebrew fixes everything!

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I actually got mine booting and working by shotgunning the chips and fixing the reset section before getting any LED flashes. Turned out to be the transistor associated with the LED.