Рубрика «Англоязычные»

Comment on Receiving GOES Weather Satellite HRIT with an SDRplay and 2.4 GHz WiFi Grid Antenna by Stephen D Frost

I respectfully disagree. RG-6 is dirt cheap and is the type of cable that is used for satellite and cable TV installations. It is swept tested for 3 ghz. A 50 foot run loses about 4.5 db. A sawbird LNA / filter at the dish gives 30 db gain and the dish itself another 20 to 25 db depending on the size of the dish. There will be a slight loss because of impedance mismatch but the SWR is only 1.5:1

Comment on Getting the V3 Bias Tee to Activate on PiAware ADS-B Images by RobR

On the Raspberry Pi running Stretch I needed to blacklist the builtin DVB-T drivers or rt_biast would fail with a “usb_claim_interface error -6” message. To blacklist, create the file /etc/modprobe.d/blacklist-rtl.conf and add these lines to it:

blacklist dvb_usb_rtl28xxu
blacklist rtl2832
blacklist rtl2830
Also create the file /etc/systemd/system/dump1090-fa.service.d/bias-t.conf and add these lines to it:

ExecStartPre=/home/pi/rtl_biast/build/src/rtl_biast -b 1

Reboot your Pi and the LNA should be powered up.

5G support

5G support submitted by /u/promach
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New monitor, unwanted side effect.


right in the centre of the marine band and business radio.

upgraded from an old dual dvi monitor to a gaming one (Asus MG278Q) on displayport.

submitted by /u/starvaldD
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Comment on KerberosSDR Preview: A 4x Coherent RTL-SDR for Direction Finding, Passive Radar and more by Thom

I was looking at your setup for passive radar. I use an RTL-SDR dongle for AIS on my sailboat. It was nice to see traffic and the circling airplane on your tests. But in both scenarios you and the reference signal was stationary. In a sailboat the reference signal will be stationary but the boat will be moving. Albeit under 9 MPH but course changes would be an issue. If using Yagi antennas one would have to change the aim of the antenna if the boat tacked onto a different course. Has it been tested at all in this type of scenario? With Omni directional antennae?

Comment on New Alternative WxToImg Website with Most Files by Farid YD1HVZ

Fix Installer if your installer always crash at windows 10

Antennas • Re: Recommended outdoor antenna for SDR?

There are active antennas that provide the frequency range you want, e.g. like the R&S®HE700 with the Rod antenna but than the price is also quite high, since with the other antenna elements it works up to 18 GHz (thats 18 000 MHz).

Models Frequency range
R&S®HE700 10 kHz to 18 GHz
R&S®HE700 Rod antenna 10 kHz to 100 MHz
R&S®HE700 Dipole antenna 100 MHz to 1500 Hz
R&S®HE700 Spiral antennas 1.5 GHz to 18 GHz

You might try an active antenna the cheapest form is a short whip with an associated pre-amplifier. For starter from an old active car antenna could do, since it had to work for AM and FM (~600 kHz up to ~108 MHz).
If you search the internet you will find ideas how to DIY e.g. http://www.g8jnj.net/activeantennas.htm.
Comercial active antennas come in price ranges from a few hundred up to and exceeding 10 000 € (e.g. like the R&S antenna above), but then you get several GHz of Bandwidth and all the bells and whistles you could possibly wish for.

For SW and below just put 5 or more meter of wire horizontally up for FM and above simple groundplanes will do, since for receive you can get away with a lot and still receive signals. You can always improve with time

Statistics: Posted by snn47 — Sun Jan 20, 2019 6:48 am

GOES 16 woes continue…

GOES 16 woes continue...

Second attempt at receiving images from GOES 16 here, using raspberry pi running goestools. After my last attempt was foiled by an issue with the bias tee of my SDR that resulted in the LNA not being powered, I was hopeful that I would get an image this time. Firing up goestools, my viterbi error rate never went below 2000, indicating no signal. However when I connected the SDR to my laptop and ran CubicSDR, the waterfall showed a clear (perhaps weak) signal at the 1.68 GHz range when pointed at the satellite's approximate location:

Definetely something


Which dissapeared when not pointed at GOES, ruling out interference

Despite not changing antenna positioning at all between running goestools and the waterfall, the latter clearly (I believe) showed some reception from GOES. My question is how is it possible to then not be getting a single packet or drop in vit rate? I don't see where there could be a fault in the hardware (in case it was my Pi I tried running goestools on a linux machine, no luck), and I find it hard to believe it's the software. Or was the signal just too weak? Thanks in advance for any ideas/help, this project is fascinating and frustrating at the same time!

submitted by /u/drwhoxenon
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Comment on Using a LimeSDR / PlutoSDR to Transmit Digital Amateur Television with DATV Express by AD5NL

I was taking a look at that myself. I was able to get it transmitting with the dvb_s2 example on my Lime, but didn’t have a receiver handy (I don’t think you can use the Lime with both gr and sdrangel at the same time).

I’ve got a cheap chinese sat receiver in the garage somewhere I bought a couple years ago, been meaning to try modding it as you did in your video to receive DVB-S/S2.

btw good videos, very educational

Troubleshooting Help • Is there any way to run audio through DAP BEFORE Aux VFO???

I'm trying to run a voice inverted signal through the DAP then out the AUX VFO to VB Cable then to a Zello application. I can get this to work if it is the selected frequency and running through the default audio device selected in Windows but when I route it out the Aux VFO it is still scrambled. Is there any way to make DAP process the audio BEFORE it is routed out the Aux VFO????

Statistics: Posted by Fireman3351 — Sun Jan 20, 2019 4:35 am

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