Resurrected a dead Flight 2000 that came with two speech cards. Apparently the game had long suffered "no speech" issues, and given what I found the cards were not the problem.
One card is a Revision C dated 1980, and the other is Rev F from 1981. Visually they are nearly identical.
When I found the source issue, I connected the newer VSU card since it had a factory labeled F2K rom, and it worked! Played a few games and all seemed proper. Then I decided to try the older card (with an unlabeled ROM). And it worked even better! Because lacking a frame of reference, it turns out the first card was actually more... chipmunky? Fast, high pitched... and during the self test ("1-2-3-4-5-etc etc") it was trailing off with faint gibberish after the "5...", such that I didn't even know it was supposed to be saying words until I put the other card in, which boomed out a consistent, deeper monotone robot voice with added words.
My kids even joked the original card sounded like "splat" instead of "blast", ha!
Anyway, I'd already ordered the kits to recap both VSU cards (and sound board) per my normal rehab procedures, but they're not here yet. Meanwhile, I'm thinking a higher pitch that increases while trailing off, might in fact indicate an actual (as opposed to "assumed") cap problem: caps losing capacity and being drained before the full sentence is spoken...? So is that indeed the case, or does that particular card have another issue? It seems these cards are somewhat enigmatic with little troubleshooting info out there (they either work or they don't, and the unobtanium synthesis chip is often a culprit).
Any idea on the going value of these cards? Provided I get both working the same, I'm torn between keeping the extra as a spare or selling to recoup some expense.