Prophet 5 Rev 3.0 2708 EPROM chip upgrade to FRAM replacement module.

Removes the 3 old 2708 8 bit x 1k Eproms and updates to a single chip 8 x 1k FRAM with 150+ years memory running on +5v only. Now +12v and -5v rails on the power supply are not needed anymore. Pre-programmed with Rev 3.0 Firmware 8.1.

Prophet 5 Rev 3.0 is Plug and Play.

1. Back up any presets. (Not needed but generally a good idea when working on any mods)
2. Remove 3 old 2708 ram ics.
3. Fit FRAM replacement module.