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There are two things related to using oscilloscopes that I am a bit fuzzy on for a practical lab exam I will take tomorrow morning:

1) Use the oscilloscope to determine the frequency of the square wave between terminals B and C of the test box. ( We will press and hold down the button on this box to activate it).

I'm guessing the box has some kind of square wave function generator built in. So, it sounds to me like I wire this up to one channel of the oscilloscope and adjust the controls until I see the square wave on screen. Then, I take one full cycle of the square wave and count the divisions on screen. Then, multiply this by the time/div setting that is on the scope, and then calculate the frequency by 1/(time)? Does that sound correct?

The next problem:

2) First, before connecting the function generator to the circuit, set its output to a sine wave that is 8 volts peak to peak (peak to trough). Next construct the circuit shown (it's a circuit with a capacitor, inductor, 1000 ohm resistor, and the function generator all in series). Adjust the frequency of the function generator so that the current in the circuit is a maximum. Use the oscilloscope to measure the circuits maximum current at this frequency.

My questions for this problem are:

a) Should the function generator have an explicit voltage scale on it that I will be able to dial up the 8 volts peak to peak voltage? I don't remember the ones we've been using this semester having that capability.

b) To measure current, do I measure the amplitude and then multiply by the volts/div setting, then use ohms law to get the current? I = V/R I am really not sure about this one.

c) Just to make sure, I put the leads of the oscilloscope across the resistor, right?

Thanks very much for any help on this. Sorry to be so long-winded!

Tim

1) Use the oscilloscope to determine the frequency of the square wave between terminals B and C of the test box. ( We will press and hold down the button on this box to activate it).

I'm guessing the box has some kind of square wave function generator built in. So, it sounds to me like I wire this up to one channel of the oscilloscope and adjust the controls until I see the square wave on screen. Then, I take one full cycle of the square wave and count the divisions on screen. Then, multiply this by the time/div setting that is on the scope, and then calculate the frequency by 1/(time)? Does that sound correct?

The next problem:

2) First, before connecting the function generator to the circuit, set its output to a sine wave that is 8 volts peak to peak (peak to trough). Next construct the circuit shown (it's a circuit with a capacitor, inductor, 1000 ohm resistor, and the function generator all in series). Adjust the frequency of the function generator so that the current in the circuit is a maximum. Use the oscilloscope to measure the circuits maximum current at this frequency.

My questions for this problem are:

a) Should the function generator have an explicit voltage scale on it that I will be able to dial up the 8 volts peak to peak voltage? I don't remember the ones we've been using this semester having that capability.

b) To measure current, do I measure the amplitude and then multiply by the volts/div setting, then use ohms law to get the current? I = V/R I am really not sure about this one.

c) Just to make sure, I put the leads of the oscilloscope across the resistor, right?

Thanks very much for any help on this. Sorry to be so long-winded!

Tim

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