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vic vic is offline
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Default Distorted oscilloscope trace

Hi,

I recently bought an oscilloscope on eBay, and I don't know if the
seller lied in the description or if it was damaged during the
transport, but the trace is completely distorted and shows strange
grid-like patterns. I made a few pictures and a little video :

http://img222.imageshack.us/img222/1984/focused.jpg
http://img212.imageshack.us/img212/6566/unfocused.jpg
http://www.youtube.com/watch?v=c5RTaTM0tJk

The shape of the trace changes when I change the y-position dial. This
makes me think the problem is in the tube and not in the electronics.

I'm wondering if this could be caused by a bent grid somewhere in the
tube ? Could it have been damaged if the oscilloscope received a shock
for example ?

I think the tube is pretty much toast, as well as the scope since there
is no way I could find a replacement tube (Tektronix 2225), but I
wouldn't mind to be proven wrong :-) Thanks.