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Ermi and all,
If you are interested in bench testing a transmitter, Ermi’s advice is excellent. He mentioned the importance of using a 10X probe and this is an often overlooked and misunderstood aspect of measurements using a scope.
He is correct and all I want to do here is to offer a bit of explanation. A 1X probe presents a load to the test point which includes the scope input resistance and capacitance plus the cable capacitance of the probe. Typically the input R of a scope is 1 Mohm with a capacitance of 15 pF. This is significant at even medium RF. A 10X probe presents primarily a high resistance load which will minimally affect a circuit.
RF measurement with a scope or a DVM requires caution since the measurements depend to a great extent on the characteristics of the measurement device and the probe. Ermi’s suggestion on using a 10X scope probe is dead on! Also, make sure the probe is properly compensated and that the bandwidth of the scope is adequate, though most scopes will suffice for the AM BCB frequencies. DVMs, however, are mostly not satisfactory for AC measurements at RF.
Moral of this story is that measurements need to be interpreted with knowledge of the methods and equipment used.
Thanks, Ermi, for the great tutorial and I hope I added some good information. I assume that you, as will I, will answer any further questions.