Author Topic: System80 power train  (Read 278 times)

0 Members and 2 Guests are viewing this topic.

Offline The pinballist formally known as Dean Morgan

  • Trade Count: (+3)
  • ******
  • Forum Posts:
  • Berwick Vic
Re: System80 power train
« on: May 22, 2012, 08:01:05 PM »
Chased my tail a bit on the non working switches... Jaycar dont sell 7400 chips anymore. The forced 5V on pin 10 was missing due to some bodgy repairs before me and a badly soldered socket. Fixed this and switches still didnt work although chip now tests a good AND gate. Turns out i had a shorted switch on one of the bumpers... LOL- so used to working on EM games where if this had happened a coil would have locked on... SS dont care.. just sees anything on this line as nothing as no pulse goes through the chip.
So all PF problems solved.
Faulty display lights very dimly if i put one leg of my meter on ground pin 2118A driver chip and other leg anywhere really... will see if Jaycar sell these still tomorrow.
I replaced all electrolytic caps on the sound board as its a bit screechy.. didnt do a damn thing. Would be nice to lower the tones a bit ( far too much top end) and get the sound cleaner...




How did u go with the 6118a driver for the display from Jaycar
anyone have any ideas on this?? Tones are set by the resistors on the 555 timer yes??... what about cleaning the sound though?
Im a Gottlieb Man - System 1 & 80 Rock