Re: SDR Radio S/N measurement
That does not tell me your circumstances, only your use. While it helps a litle (rules out Radio Astronomy tweaks) it still does not suggest what is best for you. Presuming you are passing rational (are using the RTL dongle for 50 MHz and higher) then your circumstances of interest are local noise levels and whether or not you have local high power signals to contend with within 10 MHz or so of the frequencies you find interesting. I have published for some time now a source dll for SDRC using RTL dongles. It features three different gain setting modes that set all levels at the same time. One is little or no compromise for sensitivity, one is major compromise to improve dynamic range, and one is a reasonable compromise between the two. It does not feature three individual gain settings as it's too easy to find yourself off in the woods lost and alone.toggle quoted message Show quoted text
The BASIC method for setting the gain control is fairly simple. Set the gain to about 10 dB give or take whatever. Find a signal that sticks up about 20 dB above the noise fuzz. Increase the gain step by step until you hit an increase that causes the signal and noise to increase about the same. That is maximum practical sensitivity without severely compromising dynamic range on the very limited dynamic range of the RTL dongles. If there is a lot of high power stations you may have to compromise sensitivity by dropping the gain a step or two.
You can grab "SDRSourceRTL2832Y Distribution 20180320.zip". And if you are into sharing sets of favorites the "Merge SDRC Favorites" tool can be useful. (Thanks to Leon Koning who helped debug it.
My WorldShare folder, https://drive.google.com/open?id=0B4ImLhg3WKL5fnhRalBOVU8wVmFma1ZzR25LVEZYR0RBMzBwTFh6M0psbkZOei03ZVBDeTQ, also has some useful files (and some cat pictures.)
On 20190623 01:56:18, Chris van Lint wrote: