I plan to use some contact cleaner on numerous places around my boombox controls and will have to take a few things loose. If my box has been off for a week, do I still have to worry about getting zapped from a cap?
A few minutes should be enough. Just make sure the box is unplugged from the mains (as some boxes have uninsulated transformer terminals etc). If you need to do work inside the box while it is powered up (e.g. adjusting motor speed etc) then I recommend using batteries to power it. It is good that you asked because capacitors in any tube (valve) equipment can store high voltages, so with that type of equipment waiting hours after switching off could be advisable. As for CRT (tube) TVs if the right procedures aren't followed they really could zap you even after a week. I just realised that would actually apply to the small number of TV boomboxes that were made.
