>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

It strikes me that the time has come for your customer (even if he is a
friend) to bite the bullet and buy new, because the cost and time involved
in getting this going again is going to be horrendous, and rapidly approach
the cost of a new item.

At the end of it all, even if you get it going properly, it seems to me that
the likelihood of another drastic failure in another part of it is going to
start to increase - read "climbing the far side of the bathtub curve".

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