I've recently got hold of a second hand Thandar TM355 bench multimeter. It can be supplied by either 6 "C" cells or there's a 2.5mm barrel plug for power. Unfortunately, the service manual doesn't give any more information than that one must use an "approved AC adaptor".
Looking inside the box, it seems that the batteries are just in parallel with the power input making me think that I just need to supply it with 9V DC (6 times 1.5V), but I thought I should check here whether anyone either (a) knows what the TM355 expects or (b) has experience with this sort of thing and can tell me whether my guess is likely to be right.
I presume that the "AC adaptor" that the manual refers to implies some sort of power brick: there's no obvious bridge rectifier or the like anywhere near the input so I assume that it's expecting DC.
So, the question: Is a 9V DC plug likely to be OK, or will it blow things up?
(PS: I hope this is on topic: Although it's related to a specific device, the question is one that I'd expect some electronics professionals to be able to answer, through having used one themselves)
