DL7APV Pulsare detection

 

B0329+54

 

 

First Tests with the new airspy 10MHz Bandwidth

Does the more bandwidth really help to rx more pulsars, or does the qrm around 433MHz destroy the benefit ?

A 1600 sec try on B0329+54 with both shows no big difference:

 

 

Recorded Files:

b0329+54.bin 2,5MHz 19.June.2021 14:00 UTC

b0329+54_10.bin 10MHz 19.June.2021 14:40 UTC

 

 

 

First tests were done with Airspy just to check the difference

 

 

Reference:

2,5MS 2KSPS 10 Channels 431MHz

New:

10MS 1KSPS 10 Channels 434 MHz

 

 

 

2,5MHz:

  

10MHz:

  

RFI Situation at 10MHz

 

2nd Test with B0329+54 and 900 seconds at 2021 July 15th

2,2MHz RTL Dongle and Tempo Software on Win 10 machine as reference        and                                                                          10MHz Airspy with Presto on a Linux machine

Done for all Tests with Airspy in parallel! RTL always at 431,2MHz and at first approach Airspy with 433,5MHz

WIN/RTL: 2,2MHz 900s S/N=42 (16dB) with Tempo/Win and only S/N = 36 (15,5dB) with presto                                                      Linux/Presto 10MHz 900s S/N = 72 !! (18,6dB)      so abt +3 dB for Airspy !!!!

             

 

 

        

 

Further tests with 2MHz at both Setups

Setup RTL as before                                                                                                                                         Airspy at 2MHz and 431,2 MHz as RTL dongle

 

          

   

Setup RTL as before                                                                                                                                         Airspy at 2MHz and 435,5 MHz as RTL dongle

 

 

               

         

Setup RTL as before                                                                                                                                         Airspy at 2MHz and 437,5 MHz as RTL dongle

   

   

 

Conclusion : the higher bandwidth helps a lot but this advantage is a bit reduced by qrm. Further tests with smaller Pulsars will show…….

 

 

 

 

 

 

 

 

 

 

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Last update juli 2021