Re: RF power meter calibration
Yes,
The scope's 50 Ohm termination resistor terminates the cable from the attenuator, so the cable gives a flat frequency response.
The big attenuator reduces the power sent to the scope's termination resistor so it isn't burned out. 5v RMS is about +26dBm or 200mW. Some scopes have 125mW rated terminations, but don't count on them being any more.
Relatively few scopes have protection systems monitoring the input, and even with those known to do so, it is not wise to rely on it. It doesn't always work fast enough to save the resistor or the input amplifiers. If you have protection and know it, still plan things to not need it. Let it be a back-up. Spend a bit of time getting it right and it's still a heluva lot quicker than having to fix a destroyed scope along the way.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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