SDRplay Community Forum

Hello,

What is the best way to measure power coming down to the SDR from the receiving antenna? Would a simple multimeter be sufficient?
I've read that RSP can only tolerate 0dBm (1mW).

I want to measure exactly how far the transmitting antenna needs to be not to damage my RSP DUO. I am not looking for any relay/switching products at this time.

Thank you
Pete

Hello PeterSDR,

The best system to measure the power coming from the antenna to the RSPduo......is the RSPduo itself equipped with a suitable attenuator. As an example, consider (a very, very worst case) that your receive antenna outputs 1 W (+30 dBm): inserting an 80 dB attenuator between antenna and RSPduo, the RSPduo will precisely measure a power level of: +30 -80 = -50 dBm.

Now reverse the line of reasoning: you have an 80 dB attenuator between antenna and RSPduo and the RSPduo shows a level of -85 dBm: then the power coming from the antenna will be: -85+80 = -5 dBm = 0.3 W. You can find attenuator build data and dBm/power conversion tables in the two references below. If you really expect high power, you can build the attenuators with resistors rated 1W or more.

https://www.sdrplay.com/community/viewt ... 2&start=50

https://www.sdrplay.com/community/viewt ... 3&start=10

Thank you glovisol. Exactly what I was looking for.