"Anyway I've already dumped this PROM. Here's the contents:
"0000: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF
0010: FE FE FD FD FB FB F7 F7 EF EF DF DF BF BF 7F FF
The CRC32# of the file is: 7F18F0E4
It should be a simple matter of programming new Flash Gordon speech EPROMs and the sound EPROM on the Sounds Plus board. What problem are you having that you're looking at U9?"
My non-working Vocalizer had Xenon proms, and any that were readable were corrupted. No checksums matched any Xenon images. I was thinking that U9 could be corrupt as well.
Can somebody possibly make me a new U9 that I could buy?
I replaced CR1 through CR3, new C11 and C25, and installed a new 7805. I replaced a crummy looking U12 (74LS04). I rang out all the rom sockets, they are good. I tested the IDE socket (it's good) and bought a new ribbon cable. I don't have any 74LS30's, MC3417's, or MC1403's, so I ordered some.
I made new 7532 FG eproms for the vocalizer, and a u4 7532 for the sounds plus. I tested the roms in a working vocalizer & SP, and they worked great. I know the problem is in the vocalizer, as I repaired the SP and it works fine with my working Xenon vocalizer.
What should I be checking next? Thanks much for the help!