Here i publish some screenshots of my reception of Perseids in August 2017.
This is the first approach and unfortunatly i did not program the reception in adavance so i had to do with the equipment and software available.

GRAVES radar transmit at 143.050 MHz; tuned in USB 1 KHz below to hear the sound alert when something was coming (i did not keep starring the monitor).

    • My setup was:

    • X beam antenna (more or less like a 2 el.  Yagi) on the balcony
    • 15m. RG6 cable
    • RTL-SDR.com V3 dongle
    • RTL-SDR.com FM traps (one at each end of the cable)
    • SDR Sharp software
    • QTH Pesaro, Italy, locator JN63KV
    • Date of reception 2017 Aug. 9 to 13.

All times are CEST (UTC+2)

Here below you can see how i resized the windows and zoomed to take the screenshots.
Set the sample rate to 0.25 MSPS, resize the window and zoom.
I suggest to add a new installation for SDR# and use it only for the GRAVES so you don’t have to mess with the settings everytime you want to receive it. The only thing you have to adjust everytime is the zoom; i played with the config file but i was not able to save the zoom position.

A common problem using low cost SDR for reception of the GRAVES radar is the overloading and intermodulation when some ham radio or repeater are transmitting on  the 2m. band.  The two frequencies are too closed to solve the problem with some band stop filter. This happend to me quite often while i was monitoring the GRAVES.
My antenna was mounted for vertical polarization and I did not try to change to horizontal but this should reduce the problem a little because most of the ham using the FM portion of the band use vertical antennas.

Update: i tried with the horizontal V dipole and the local transmissions on 145 MHz are not overloading anymore. I also received some short reflections from the GRAVES.
Considering that many people use vertical antennas like G.P. or J Pole the horizontal V dipole could be a good solution.

Future plans are a homemade 3 or 4 elements Yagi and some sofware for unattended video recording of a portion of the screen.

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