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8

Xastir is most likely what you want. http://xastir.org/index.php/Major_Features#SUPPORTED_TNC.27s:_DARN_NEAR_EVERYTHING.21 YACC - Yet Another APRS Client is also a newer choice. I have not personally tried it. http://www.ka2ddo.org/ka2ddo/YAAC.html


6

There are a lot of things wrong here. Neither plot looks correct. There is no way that Qt plot is realistic for anything but a signal generator. Where's the noise? Where are the three missing constellation points in the Qt plot? APRS isn't QAM (it's AFSK over FM), so I'm not sure why you are expecting QAM. You don't have any filters, clock recovery, or ...


6

2m isn't a good band if you want to do anything digital. Digital modes just aren't very popular on 2m. I think the only digital activity you are likely to find is: D-STAR APRS D-STAR uses GMSK, but the data for voice transmitted on that channel relies on a proprietary codec called AMBE. Any software that can encode or decode it is almost surely illegal, ...


5

The R820T and the R820T2 differ. The R820T can set a narrow IF filter (300 kHz) - but not if the gain is set at maximum. The R820T2 can not set a narrow filter - minimum bandwidth is about 800 kHz. This is easy to see when one runs the dongles with a spectrum display software having nothing connected to the antenna input. I use Linrad, set the IF filter to ...


5

What are the best hardware options for this considering the bandwidth and frequency requirements and availability of stable linux drivers. (I was thinking one of the SDRPlay family of devices but would welcome input on this) So quick summation of your requirements: at least 10 MHz analog bandwidth and 10 MS/s (complex) or 20 MS/s (real-valued) sampling ...


4

You could use Aprx or Direwolf and configure the client as a Receive-only iGate. You can then assist in sending some directly received data to APRS-IS (the Internet side of APRS) and see the data appear on sites like www.aprs.fi You will need a password to be able to log to aprsis but this is trivial once you have a callsign and google for aprs password ...


4

I've used CQRLOG which is built on MySQL but otherwise has many of the same features as other loggers and is fully customizable. If that's too much and you're looking for a simpler solution, Xlog is a barebones logger that can still interchange data with some of the Linux PSK and other digital mode software. Both support all the popular export formats, ...


4

In absence of a clear indication of what Amateur Radio band is being targeted here, an answer for the 13 cm band: You can use 802.11g/OFDM with a 20MHz bandwidth on 2400-2450 MHz Amateur band. You could even modify existing/consumer Wifi equipment to do so. This would give you a (theoretical) 54 Mbits/sec throughput. Obviously you need to check that you ...


3

As far as I read the rtl_sdr source code, no, there's no special case for anything called "820T2"; the relevant file is rtl_sdr.h: enum rtlsdr_tuner { RTLSDR_TUNER_UNKNOWN = 0, RTLSDR_TUNER_E4000, RTLSDR_TUNER_FC0012, RTLSDR_TUNER_FC0013, RTLSDR_TUNER_FC2580, RTLSDR_TUNER_R820T, RTLSDR_TUNER_R828D }; ...


3

No. Most radio peripherals will not pass raw RF samples to or from the host computer, but only fully decoded packets. I'm not familiar with that particular card, but I'm sure if it had such capabilities people would be talking about it. (The so-called “RTL-SDR” TV tuner device does have this mode of operation, which is why it is so popular for cheap SDR ...


3

If the tone is, or can be made to be, a DTMF tone or one of several other simple tone code protocols, then you could use multimon-ng to detect it. multimon-ng will output text corresponding to the detected tones. This also means you don't need to program the amplitude criterion. Something like this: rtl_fm -f <freq> -s 22050 -M wbfm | multimon-ng -a ...


2

A simple way to get a Linux logger is to use a windows logger under WINE Windows Program Loader, or something similar. I've done it before and it works fine, however it can cause problems on a slow computer.


2

The signal interface with traditional hardware radios (such as those controlled by hamlib) is through an audio device (sound card). A glance at QSSTV's manual looks like it works that way. SDR programs generally output the demodulated audio to an audio device. Therefore, what you need is a loopback audio device, one which is used as an output by your main ...


2

This is issue #42 on Direwolf's GitHub page. https://github.com/wb2osz/direwolf/issues/42 To work around it, put the interface into CRC mode "none" with a command like this: # kissparms -c 1 -p radio


2

I haven't really tried this, so beware! I thought the output, as recorded in the file, would actually be the samples in a certain format. So I tried to look it up, and found this page: http://sdr.osmocom.org/trac/wiki/rtl-sdr#rtl_sdr At the bottom of the page is a flow diagram for gnu-radio, which takes the contents of the archive, and de-interlaces it (...


2

4 Raspberry Pi's each with an RTL-SDR dongle may well be cheaper than just one of the higher bandwidth SDR capture devices or a high end Linux PC. They run Linux. Network them together, with each one capturing a 2.5 to 3 MHz slice of the RF spectrum of interest, totalling over 10 MHz. That will also allow offloading your main Linux box, and allow doing ...


1

If you're running under WINE, you can make the port whatever you want. You need to know the Linux device name (like /dev/ttys0 or /dev/ttyUSB or whatever) the TNC is plugged into on the computer. Then all you do is set up a symlink in ~/.wine/dosdevices that "connects" the two. If you look in that directory, you can see the default devices already set up. ...


1

This is actually implementable, as specified, but you may have to code your own app. I wanted to measure whether 2 signals were present. So I ran rtl_tcp on my Pi 3 to serve RTL-SDR IQ samples over a socket. I then wrote 2 DSP filters (in C) that connected to rtl_tcp and measured the magnitudes of the two signals, ran the filters on the Pi 3, and printed ...


1

You didn't specify the OS of the client from which you would like to view the remote session. On the Pi side, use the built in RealVNC to allow remote access. If your remote client is Linux based, take a look at Remmina. It is a free, open source project with support for several Linux variants. If your remote client is Windows based, evaluate TightVNC. It ...


1

This page appears to be what you're looking for. This technique uses the Linux LV2 plugin. You'll have to build an interface with a 555 timer chip. SETUP: an UltraPico Keyer, keys a 555 TIMER CHIP..from the audio output of the 555, an audio cable is attached and goes to the input of a laptop's mic jack input...the 555 time chip sidetone is very rough ...


1

The recording in rtl_sdr can be played in gqrx by following the below procedure carefully: Either A or B: (A) Create a gnu radio program with the flowchart posted by @jcoppens above. A copy can be found at the rtl-sdr site, but as mentioned on Stack Overflow, the rtl-sdr .grc file uses obsolete modules and must be rewritten in the new gnu radio companion (...


1

I'm a software builder and packager. While I don't have any use for cuSDR at the moment, I looked at the svn repository and home page, and did some googling: there was no Linux installation documentation that I could find. there was no common build scripting in the repository. there were no Linux packages prepared. there does seem to be discussions about ...


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