PET problem SOLVED!

[Gordon JC Pearce]

Dave Dunfield said:

> Checking the Schematic, bit 1 of the low memory bank is U17 - pulled it,
> put in a
> socket (always!) and stuffed another 4116 - voila!!! it came right up!

Ah... 4116es!  How much money did I make at school, fixing ZX Spectrums
that had weird black-and-white stripey stuff on the screen..?  Almost
always, you'd find that one of the eight 4116es had failed, and was
(coincidentally) pulling the +12V line from the dinky little chopper PSU
down, which also fed the chroma modulator...  Hence the black and white
screen.

Gordon.