开云体育

7B7 new typo Chris? A 7B87 would be nicest for single sweep records with pretrigger, so you can view the leading edge of the spike and probably the whole spike. Things also depend on the time span of the spike, so on the time/div setting for a good display of the spike. Fast sweep rates can not be recorded in a single sweep. Details for a 7B87 can better wait I think until it's sure that you have one.
You can set the trigger level to above +5 V like John suggested and then record a single sweep. You might also close the curtains and dim the lights and hope you see the real time single sweep. But you might miss the leading edge or more of the spike. Then you might try a delaying/delayed time base setup. Set the 7B85 for triggering at about +2 V (so for triggering immediately when you switch on the power) and slow enough speed to see the spike occurring also. Next set the time bases for delayed sweep and "starts after delay time". Choose a proper speed for the delayed sweep and a proper delay time at the 7B85 to catch the spike (lights dimmed even further...).
Of course for the PS this means power off and on many times.

Albert


---In TekScopes@..., <chris@...> wrote :

Sorry, a typo, I read my poor handwriting of 7854 (the mainframe
itself) as a 7B54! You are quite right, the other plugin is a 7B7!
Apologies. Thank you very much for the clear and detailed
instruction, but one question, was I clear in explaining this spike
is a single one, just at turn on? Not an ongoing event like ripple? I
will try your instructions and report back, thanks again. I was
expecting to have to use the storage facility, this looks a lot more
straightforward.


Best Regards,
Chris Wilson. 2E0ILY