My first scope was a 2213A. I got it from the auction site. Stated all was working 100%. After powering on for several minutes it would lose its trace and go crazy. The previous owner had removed the board and there are little tabs that hold the board in place. One side of the board was not fit into the tab and the board was bent. after removing the board and making sure the board was in its proper place it has worked fine since and that was 7 years ago.
Brendan
