I have a 10 MHZ time base circuit (see attached). It goes through a chain of 74LS90s to divide it down to 1 Hz.
It count up to 99999 just fine. When probed with my scope, I get messages such as "Sine Wave Detected on Ch1",
"DC Level Detected on Ch1", "Unknown Signal on Ch1" and sometimes "Square Wave or Pulse Detected on Ch1".
If I feed a 10 MHZ square wave into the counter chain with my function generator, there is a good clean square
when various points are probed.
Any suggestions would be appreciated.
Thanks
It count up to 99999 just fine. When probed with my scope, I get messages such as "Sine Wave Detected on Ch1",
"DC Level Detected on Ch1", "Unknown Signal on Ch1" and sometimes "Square Wave or Pulse Detected on Ch1".
If I feed a 10 MHZ square wave into the counter chain with my function generator, there is a good clean square
when various points are probed.
Any suggestions would be appreciated.
Thanks
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