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Does the RESET circuit function correctly, sounds like it doesn't? It should go to approx 0v on switch on and then after about a second switch to 5v. You shouldn't need to 'jump' the RESET obviously but I would make sure that part is all working first as it will save you time. Depending what mod state you have will depend on what parts may be faulty. Moving on to the no boot is where it can get tricky. Assuming your ROM chip is OK, test by substitution, then you are getting in to logic probe or even scope territory. I wouldn't recommend a scatter gun approach either of swapping all the support chips (unless things get desperate, been there a few times) as that can lead to all sorts of added problems of pad lifting, broken vias etc unless you have all the right gear of course. It'll be a good idea to do IC9 & 24 anyway as you may hit lucky. Watch you don't pull any pads off though as some of the pins are soldered both sides

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No, it should start at 0v and then switch to 5v after approx 1 second ish. No point keep changing the transistors as it's unlikely they are bad again. Looking back through the thread I see you had removed the spark circuit so that's eliminated. The timing of the RESET pulse is set by R76 and C36 which you can monitor by reading the voltage from R76/T57 to ground on switch on. It should start at a low voltage and rise to somewhere 12-15v if I remember. If that's happening then T57 should be switching when it's collector voltage reaches the threshold of the 9v1 zener on it's emitter which in turn switches T58 on and T59 off....bingo 5v on the RESET line.

Succes IMG_3349.MOV