开云体育

On 2021-01-25 19:41, Tom Lee wrote:

Very cool, Arie -- I've never seen a scope with a P12 phosphor -- only
vintage radar sets. Might be useful with an SA plug-in when doing narrow
RBW sweeps.

Tom

Well, it appears neither have I...

After removing the bezel and orange filter the trace clearly shows as a blue dot with a green afterglow. So, just as Jeff Dutky already expected, option 76 is a P7 long persistence dual phosphor, in this case plus an orange filter. When shining UV on the bare CRT the fluorescence and (long) phosphorescence are both green.

I tried to take pictures in a dim room, they show at least two traces on the 0.5s/div speed (10 seconds total). I uploaded one to /g/TekScopes/album?id=259869 Look at it full screen, dark room.
When setting brightness optimal, in a dim room the naked eye can see three sharp traces (15 seconds). In a normally lit room it would be great for displaying an ECG signal. Maybe that was the original use.

So, riddle solved. Thanks for the great support here!

Arie de Muijnck