You won't see a signal from the preamplifier when there are no input
changes between sample moments
So if 7S12 is not "processing" the trigger from S-53, then S-4 may always
be sampling the "same" spot in time, hence no signal (if I understood this
correctly).
Hi Nenad,
This is not what I meant. After each sampling event the 7S12 memory and vertical screen position are updated to reflect the new input signal voltage. At the same time the whole sampling gate circuitry voltage values are updated such that the bridge follows the input signal voltage. If at the next sampling event the input signal is still the same then the bridge voltages remain the same. When the input signal changed meanwhile then a new correction to the bridge voltage is needed. This will happen because the preamplifier detects the change in the form of a short pulse sent to the 7S12 for further processing. The pulse gets larger when the input change is larger, for instance at the jumps of a square wave. In many applications the horizontal dot distance is short enough to show a smooth trace at the screen. Then the separate corrections in vertical distance are very small.
There is much more explanation in the 7S11 manual. The time base 7T11(A) is much more complicated than the time base counterpart of the 7S12. The 7T11(A) can also do random sampling.
Albert
