> If the chips are socketed or you have good soldering equipment
> so the risk of board damage is low, I would replace them.  But if
> there is any risk of damaging the PCBs and the chips weren't out
> stressed beyond spec I would leave them be.  Check if their outputs
> may have been stressed by high currents at the higher voltage.
> Also check any bypass caps that may have been over voltage.
>
> Sherpa Doug

Cheers. It's still a coin-flip. The ICs aren't socketed, but the
soldering's not too bad. On closer inspection (totting up the
ICs that are probably poked) several of the boards have TTL
which will have to come out. Many of them are the original 74xx
series which are hard to find now (or expensive). From what
I can glean from the web, there should be no problem replacing
them with HC or LS. The thing is, it's not just a simple clock. The
Master is set to GMT and local time. Although they must be using
GPS timing now, the secondary function of the master clock is
still needed - that is as a driver for the dozen solenoid slaves
around the ship. The overall logic is certainly replaceable by a
PIC or two but the gamble is whether it can be done by the 25th.

Hmmm, time for a cuppa and a stare

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