Which PDP-8, PDP-11, Etc., Components Require Protection from High Humidity?

Hello Bob, I think 45% is rather dry. I'd keep going with 65% which seems to be fine as well. I can only speak about my particular experience covering some particular bits and pieces. The pdp8/L, pdp8/e, TU56, RK05 etc. boards seems to like frost free and dry storage MUCH (!!) better than anything else. I have seen massive differences in reliability. So just pull the cards and take them into the house. Wirewrap backplanes are quite robust. TU56 drives: Can literally survive water in the basement. Motors tend to rust. Keeping in the garage should be no problem. RK05 drives: You can even store them outside, but not with too much rain. I have units that were stored outside. And they just work better than other units stored somewhere in a basement. Leave them in the garage. PDP8/e and /l PSUs tend to become rusty if stored in really moist conditions. Not very beautiful - but function seems to stay perfect. Except for the boards and most-beloved front panels I'd keep the stuff in the garage. The garage should not float in water. Condensation on the parts should be avoided. But: Keep the disk packs dry! At last: Honeywell X16 gear can be stored under any conditions. Outside with humidity and frost. The cosmetical condition may change. And switches will oxidize. But the machines themselves seem to be impossible to destroy due to the kind of ICs they were using :-) Kind regards Philipp -- Dipl.-Inf. (FH) Philipp Hachtmann Buchdruck, Bleisatz, Spezialit?ten Alemannstr. 21, D-30165 Hannover Tel. 0511/3522222, Mobil 0171/2632239 Fax. 0511/3500439 hachti at hachti.de www.tiegeldruck.de UStdID DE 202668329