Using an external 50 ohm termination on my DSOX3024, is there a way to directly meausre power level in dbm?

Using an external 50 ohm termination on my DSOX3024, is there a way to directly meausre power level in dbm?

- You want to see the time domain POWER waveform? On a LOG scale? Why?

I don't think any scope anywhere does that.

If you get a rectifying Schottky diode, provide a power envelope, but on a linear scale (W or mW).

maybe a power meter would better suit your needs? I believe some can show the time domain waveform like you want, natively. Agilent also recently released this tool:

http://cp.literature.agilent.com/litweb ... 8126EN.pdf - It's all about convenience. I have an RF power and voltmeter. It would be convenient if I could meaure it on the oscilloscope and not have to drag out another piece of test equipment.

The DSO-X3024 already has a 50 impedance and can measure several parameters including RMS. So why not have a selection for dbm ? It's just math! When the 50ohm impedance is turned off the dbm selection in the measurements menu would be disabled.

A) You can use the FFT Math function to determine the power level of your signal (in Vrms or dB).

B) You can drop your signal over a 1 Ohm resisor and use the equation P = (V^2)/R where R = 1 and therefore your power will equal your voltage reading squared. This will give you your power level in Watts, not dBm. To convert to dBm you need to use the equation dBm = log(Power/1mW). Keep in mind that 'Power' in the previous equation must be in the form of mW.

**Important note for Option B above: Make sure your 1 Ohm resistor has a sufficient power rating for your test. If you're dropping 5 Volts accros it then you need a resistor with a power rating of greater than 25 Watts.