I hope I can get the answer to my question. Using Tektronix THS720A I was checking two identical 160 kHz outputs of two identical controllers. With all settings on O-scope being the same, I have on the screen a steady sign wave from controller A. When I check output from controller B, the same exactly sine wave is constantly "running" throughout the screen (sort of on the old analog O-scopes, where you have to use time/div controls to make it steady). I tried to use time/div adjustment of THS720A to "froze" it, but the only effect is that the wave shape is being stretched or compressed. The only way to capture it steady for controller B is to use RUN/HOLD control in HOLD mode.
Both wave shapes are exactly the same (an approximated sine wave). Both controller A and B were checked with their respective loads disconnected. Would it be 160 kHz generating circuit of controller B a potential problem? It appears as the sine wave is being produced, then there is an instant interruption, and when new wave starts going out again, it's thrown of phase; then same thing happens over and over again, keeping the wave shape on the screen constantly "running"?
Both wave shapes are exactly the same (an approximated sine wave). Both controller A and B were checked with their respective loads disconnected. Would it be 160 kHz generating circuit of controller B a potential problem? It appears as the sine wave is being produced, then there is an instant interruption, and when new wave starts going out again, it's thrown of phase; then same thing happens over and over again, keeping the wave shape on the screen constantly "running"?