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A scoping question
I am going to try my new rotary out on sunday, and since the coil is
permanently situated at the museum 50 miles away, I want to be well
prepared, since I can`t just run back to the workshop and fix something
up.
To monitor the primary capacitor voltage, I will use the fiber probes,
with the 50kV transducer across the cap, and in order to get all 3
breaks displayed relative to 50 Hz, I must trigger on the primary
voltage into the pig, right? (this will be with the 500V transducer and
the other channel of the receiver).
I will then adjust the electrodes for equal bang size.
However, with the lowly Gould 20 MHz scope, That I have been using up to
now, I have had problems locking on to the slow 50 Hz signal, while the
coil was running. This was sensing the secondary field with a small
antenna (but it survived being 4 meters away from the coil).
I now have a Tektronix 485 (350 MHz), which I bought because I assume
that such a great analogue scope would have better ability to lock to a
slow signal. (This is all something that I have heard, I have little
experience in this field).
I have about 10 meters of optic fiber cable, so the scope can be
situated safely in the trunk of the car, that long away from the coil,
but the question is this, should I expect the scope to be able to
trigger on the 50 Hz signal at one channel, in the presence of a 100kHz
signal on the other channel, or do I have to make some sort of pulsing,
or a square wawe at 50 Hz, to enable the scope to sync reliably on 50
Hz? And if, how do I convert a sine wawe to square in a simple fasion
(there is little time, now)?
I have rather great expectations to this scoping event, since the scope
has a delayed sveep function, allowing me to focus into part of the
signal, I imagine a shot, where i see the top trace documenting the
positioning of the breaks relative to the 50 Hz signal on the bottom
trace, and then a zoom in on one of the ringdowns, hopefully displaying
details about whatnotch quenching is occurring. Would be quite an
informative screendump, if I manage to capture it on film from this
analogue scope.
Cheers, Finn Hammer