Questions about using my scope
turbosupra
Posts: 1,088
I took some scope samples tonight on a signal that has 2 states. I'm not sure what all of the values under Channel 1 represent though and I couldn't find anything in the help file.
Going left column top to bottom and then right column top to bottom (these are guesses, are they correct) :
Negative voltage
Positive voltage
Peak to peak voltage
Peak to peak voltage for a signal that is positive and negative
Frequency rising edge occurrence to next rising edge occurrence in milliseconds
Frequency in cycles per second
Not sure
It looks like the signal is right around 312 cycles per second, why does the scope show a low of what appears to be below 0 volts, especially in DC mode? Am I correct on my symbol interpretations for the symbols under the channel 1 values?
For my school project, I need to calculate the proper capacitance using Xc = 1 / 2∏fC so I want to make sure I get the frequency correct as well. Thanks for reading!
DC sample in the "OFF state"
AC sample in the "OFF state"
DC sample in the "ON state"
AC sample in the "ON state"
Going left column top to bottom and then right column top to bottom (these are guesses, are they correct) :
Negative voltage
Positive voltage
Peak to peak voltage
Peak to peak voltage for a signal that is positive and negative
Frequency rising edge occurrence to next rising edge occurrence in milliseconds
Frequency in cycles per second
Not sure
It looks like the signal is right around 312 cycles per second, why does the scope show a low of what appears to be below 0 volts, especially in DC mode? Am I correct on my symbol interpretations for the symbols under the channel 1 values?
For my school project, I need to calculate the proper capacitance using Xc = 1 / 2∏fC so I want to make sure I get the frequency correct as well. Thanks for reading!
DC sample in the "OFF state"
AC sample in the "OFF state"
DC sample in the "ON state"
AC sample in the "ON state"
Comments
Hanno?
Peak high voltage Period
Peak low voltage Frequency
Voltage swing ??
??
John Abshier
Sorry I took so long- travelling...
The bottom left is the "average" of the signal: avg=sum of measurements/number of measurements
The bottom right is the "root mean square" of the signal: rms=sqrt(sum of measurements^2/number of measurements)
See: http://en.wikipedia.org/wiki/Root_mean_square
Hanno
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Co-author of the official Propeller Guide- available at Amazon
Developer of ViewPort, the premier visual debugger for the Propeller (read the review here, thread here),
12Blocks, the block-based programming environment (thread here)
and PropScope, the multi-function USB oscilloscope/function generator/logic analyzer
Assuming that because you didn't correct my other labels, then they were correct and the list goes
Negative voltage____________Frequency rising edge occurrence to next rising edge occurrence in milliseconds
Positive voltage_____________Frequency in cycles per second
Peak to peak voltage_________Root mean square
Average of the signal
Or was John correct and it goes like this?
Peak high voltage Period____________Frequency rising edge occurrence to next rising edge occurrence in milliseconds
Peak low voltage Frequency__________Frequency in cycles per second
Voltage swing_____________________Root mean square
Average of the signal
max: maximum measurement in V (search for highest sample)
min: minimum measurement in V (search for lowest sample)
peak to peak amplitude: difference between max and min in V (max-min)
average: mean of samples (total all samples then divide by number of samples)
period: time between repeating waveform in seconds (use a state machine to find repeating waveform then measure that time)
frequency: frequency of repeating waveform in hz (1/period)
rms: root mean square of signal (square root of sum of squares)
Hanno
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Co-author of the official Propeller Guide- available at Amazon
Developer of ViewPort, the premier visual debugger for the Propeller (read the review here, thread here),
12Blocks, the block-based programming environment (thread here)
and PropScope, the multi-function USB oscilloscope/function generator/logic analyzer
From the left column down:
1. Vmax (peak)
2. Vmin (peak)
3. Vmax-Vmin (peak-to-peak)
4. Vave (average/DC value)
From the right column down:
1. T (period of waveform = 1/f)
2. f (frequency of waveform = 1/T)
3. RMS
The "line" that's visible doesn't mean the "zero" line--it simply indicates which measurement is being displayed, so the top left item isn't peak negative voltage, it's the peak maximum voltage of the waveform.
--Scott