@PhilCohen 's post on pre-buying equipment and preserving it reminded me of a concern I have. This thread will also be useful to him for storing his gear.
I have some old vintage/legacy type gear that I am not currently using, but am not willing to get rid of (largely for sentimental reasons plus I fancy I might set some of it back up ...with modern speakers).
I will list concerns that (I think) I know about and hope you will flesh it out with better detail.
So, for gear that is in long term storage:
Phono - manually rotate the platter on occassion...I'd say quarterly. This will spread and grease of lubricants in the gearing and prevent the motor from taking a "set" in the stored position. Any belt (which is likely to need replacement anyway) will stay more flexible. I inferred this from how we stored mechanical equipment at the nuclear plant (much equipment is installed years before they push the "on button" and it is important everything work when you do).
Optical disc players - Cycle the disc drawer and let the disc spin up quarterly (same philosophy as for phono)
Preamp - No maintenance concerns (?) Do they have smaller capacitors that need to be recharged?
Amp - The capacitors should not be allowed to completely empty, so unit should be plugged in and turned on periodically (no need for signal). However, I have no idea how often this should be done or how long!
Thanks!