hi! i just bought an old(er?) 3M portable overhead projector for cheap. i bought it used, and when the seller turned it on something blew and the light turned out as he was trying to move it. there is a large red on/off switch, i think, i cant find any other way to turn it on. i dont know if the light bulb blew or there is something else that needs fixed. i also cant find a model number on it anywhere. id really appreciate any help. tks!

kim, July 2008

in my case there appears to be a crack in the glass surface that goes down vertically. could this stop the OHP from working? - there is no light on and even the on/off button has no light working.

clasina, March 2013

Inside they are very simple. It is either the bulb or a fuse.
Bulbs can be bought online for about a fiver, and are easy to replace. I recommend you remove the bulb, and see if you can see the filament broken. If it's the bulb, most likely when you turn it on, the fan will still start spinning. If it's the bulb, easy fix.
If the bulb is OK, it may be a fuse. These are located in different places depending on the model.
Also, if it's one with a door that opens on the side, there are switches so that it cuts power when its open. Try checking that.
Hope this helps

P Buzza, August 2008