On Sat, Jun 27, 2020 at 02:37 AM, Michael W. Lynch wrote:
I do not know if this is relevant, but I have a 485 that did a similar thing.
The square wave supplied by the calibrator was fine when the trace was
centered and as you moved the trace away from center, the trace shrank
vertically .. the problem ...a very dirty
beam finder switch.
Thanks Mike, very relevant, I cleaned up the beam finder switch and the difference between bottom and top height is now 1.8 and 2.5 squares (1:1.4) so an improvment over 2.5 and 4 squares (1:1.6). Beam finder switches clearly don't get used much!
Regards,
John
