Wiardgroup

> as short as two years. SMD seem like it will have the same problem as early eight bit 
> digital. The rate of change is very highly accelerated. 2708 EPROMs are still available, 
but 
> you need an old programmer to recognize them.
> 

Somebody asked what a 2708 is. The 2708 Eprom was a 1K x 8 bit device used to store 
the operating system of some very early digital musical instruments.

Someone once told me the Buchla 400 has 16 of them in it. Don't know if that is actually 
true. But it is a real problem for keeping those instruments alive. You need to pull all of 
them, read the binary files and store the files. Then have backups of the chips to program 
in case some go bad.

Musical instruments are about the only case where the concept of "archival" applies to 
electronics. There are 300 year old harpsichords still in use. Some very old pipe organs. It 
is not unreasonable to hope some of the instruments from this century can be kept alive 
and playing for a long time also. Wiard modules are painstakingly designed to last as long 
as possible.

Electrolytic capacitors have around a 20 to 25 year lifespan. The only module that has 
them in the signal path is the Borg filters. There was no way around it. Everything else is 
DC coupled and there is no component in the signal path with a known limited lifespan. I 
expect them to function for a century at least. I know that is not important to most users, 
but it is all part of designing for everyday reliability.

Waveform City #3 just came back for service and all it needed was new pots and one new 
jack (switch contact failed). It was still in calibration after 8 years in the field. Gotta love 
that solid state technology (and those quality trim pots).