wrote in message
...
Hi,

I'm currently having trouble with my good-ol' HM1005. It has some
problems focusing correctly.
When it's cold, you first see nothing on the screen. Increasing
intensity results in an almost completely glowing screen, looking like
an EL-backlight. Leaving it on for some minutes shrinks the glow more
and more to a spot (in X/Y mode) or to a horizontal line (in normal
operating mode). Now it's possible to use that thing, but it's not
completely working correct.
On the left side of the line the beam is more intense. I've made a
photo of that, please have a look at
http://www.preamp.org/dinge/hm1005.jpg.
Using a time base of 50ns shows some kind of overshoot next to that
bright spot. The trace is moveable to X and Y as it should (I did that
on the photo, so the bright spot is not on the grid).

I'd appreciate any kind of help that can lead me to the source of this
strange behaviour.


Thanks in advance and with best regards from Germany,

Lasse


Did it gradually or suddenly go wrong?
If you feed in a known accurate ,say, 1V pk-pk 1KHz signal in, does it give
the correct screen indication of 1V, 1KHz with relevant settings ?


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Diverse Devices, Southampton, England
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