Finally received the optocoupler today, did some cold start up measurements again before installing
Harddrive and Floppy removed just CRT
5 Volt rail - started 5.4 drops kept dropping to 4.66
12 volt rail down to 10.58
Replaced Optocoupler
Harddrive and Floppy removed just CRT
5 Volt Rail - Steady 4.89 slight fluctuation between 4.89-4.88
12 Volts - steady at 10.94
Adjusted PP1 to get
5 Volt at 4.98
12 Volt 11.16
This is looking good all voltages are steady, Who ever suggested the optocoupler deserves a medal
Plug in HD and Floppy
5 volt rail goes down to 4.83 ( Should this be a concern or adjust the rail higher?)
12 Volts goes up to 11.77
But It boots, quickly, well around 20 seconds, I have no start up sound but playing a game of Lode Runner I had some sound?
Will do the Logic Board Caps next.
1. Some questions, should I go 7.1 or 7.5 on a BlueSCSI ?
2. What is a good quiet replacement fan ?
3. Should I be adjusting the voltage higher atm or wait until I get BlueSCSI
4. Would the sound most likely be cap related LB
And thanks to this forum I would never have got this far already bidding on a new project Mac already