Written by admin 10 comments posted in amateur radio hf rtl sdr tagged with hf noise floor rtl sdr rtl2832 rtl2832u january 17 2017 lowering the noise floor on hf with high quality coax bonito is a company that sells various products such as their own small active antennas.
Sdr noise floor reduction waterfall.
Between two radio systems with the same antennas the system with a lower noise floor better noise reduction will be better.
Unless you put an lna in front of it.
First i measured noise using cw mode with a 100 hz bandwidth.
3 is now 1850 khz when using the network interface and 230 khz using the usb interface.
That s actually the more likely the noise that most people see than thermal noise.
This will allow signals to be more visible in the fft rf spectrum and waterfall displays.
With the rtl sdr having an 8 bit adc you hit sampling noise pretty quickly.
The bandwidth for the afedri sdr net ver.
This is an rtl sdr software defined radio receiver with rtl2832u adc chip 1ppm tcxo sma f connector r820t2 tuner and aluminium case with passive cooling.
It should like any other receiver have a certain noise floor nf but this figure was hard to find on the internet so that i decided to measure it myself.
Tunes from 500 khz to 1 7 ghz with up to 3 2 mhz 2 4 mhz stable of instantaneous bandwidth.
In this blog i will describe how i measured the nf the.
If you are looking for a decent hf sdr at a great price look no further than the afedri sdr net.
The importance of noise reduction signal is measured against electrical noise similarly to measuring the height of a mountain from mean sea level called signal to noise ratio.
But you may find the display will drop off the screen so no waterfall is visible this can be altered under the display tab and the spectrum scale i run mine on auto for the high and 140db for the.
Ultimately your thermal noise is dependent on what you put in front of a rtl sdr.
You should adjust this so that the noise floor sits near the bottom of the rf spectrum window.
Vertical axis of the rf spectrum window.
Sdr digital noise reduction.
I ran two receivers rsp2 and perseus side by side sharing the same antenna on the same frequency.
The afedri sdr net receiver covers the hf band from 100 khz to 30 00mhz.
Rtl sdr blog r820t2 rtl2832u 1ppm tcxo sma software defined radio.
Sdr spectrum noise floor running the numbers.
My objective was to calculate sdr spectrum noise floor from first principles using the above formula.
I ve recently received an rtl sdr dongle and i m picking up a lot of noise that is probably coming from my pc especially a lot of spikes on the 2m band.
What else can i do to reduce the noise floor and get rid of the rfi on 2 meters.
The rtl sdr is an ultra cheap software defined radio based on dvb t tv tuners.
