Vertical Amplifier rotation
 

I have a Tektronix 465M scope (AN/USM-425(v)1 with an odd problem. I
first noted that the trailing edges of square waves seemed to slope
backwards. A little troubleshooting led me to the following, which
seems to be in the vertical deflection amplifier.

Placing the unit in X-Y mode and attaching a sinewave to Channel one I
adjust the amplitude and trace rotation to get a perfectly horizontal
trace on the graticle centerline. Disconnecting channel 1 and
connecting the same signal to channel 2, I *should* get a perfectly
vertical line. Instead, I get one that is slanted almost two minor
divisions top to bottom. That is, if the to of the line is at the
exact center of the top line of the scale, the bottom of the vertical
line is almost two minor divisions to the left of the center of the
bottom line of the scale.

It's like the vertical axis is rotated, but the horizontal axis is
fine.

Vertical Amplifier rotation
 

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I have a Tektronix 465M scope (AN/USM-425(v)1 with an odd problem. I
first noted that the trailing edges of square waves seemed to slope
backwards. A little troubleshooting led me to the following, which
seems to be in the vertical deflection amplifier.

Placing the unit in X-Y mode and attaching a sinewave to Channel one I
adjust the amplitude and trace rotation to get a perfectly horizontal
trace on the graticle centerline. Disconnecting channel 1 and
connecting the same signal to channel 2, I *should* get a perfectly
vertical line. Instead, I get one that is slanted almost two minor
divisions top to bottom. That is, if the to of the line is at the
exact center of the top line of the scale, the bottom of the vertical
line is almost two minor divisions to the left of the center of the
bottom line of the scale.

It's like the vertical axis is rotated, but the horizontal axis is
fine.


Have you tried it after turning the whole scope to different compass
orientations. ?

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