Tech / Special Interest → Ham Radio > anybody here doing packet on 2m?

anybody here doing packet on 2m?

I'm only just starting with ham radio and got into it primarily for emergency communications purposes. It also seemed at first to be a relatively inexpensive hobby when I saw the prices for wide-band SDR usb receiver sticks ($20) and chinese handheld radios ($35). I have since then been to the local HRO so no need to explain explain prices to me

What I'm currently trying to do is simply listen to packet traffic which for EmComm around here is pretty much all AFSK1200 primarily on the 2m band (some also on 1.25m/220MHz).

The two ways I have attempted to do so are:

1.) SDR usb stick (I tried two different kinds) with gqrx software and its afsk1200 decoder.

2.) Baofeng UV-5R+ with a Kantronics tnc.

So far neither attempt has worked (I never got a single character out of #1 and only rare packets using #2). I should probably add that I tried a number of different antennas with no difference in behavior (I don't think it is a signal strength issue).

What I'd like to know from those that are using packet is what equipment you are using, what has and what hasn't worked for you and probably most of all what kind of tuning is needed to successfully decode afsk1200 ?

There are plenty of reports on the Internet of using either method (or other combinations such as Baofeng to soundcard modem) but very little detail on what exactly was done to make it work. It always sounds as if it simply works which so far it hasn't for me.
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Can't speak for the SDR problems, but turn off the battery saver on the baofeng... it will clip the packets and they won't decode. (experience talking here...)
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"When the hammer drops, the bullshit stops"

I have a Kenwood TH-D7 and it has a built in TNC. My issue is findng software for Windows 8. I got Hyperterm to work in Windows 7 but I switched laptops.

Putty has serial capabilities and works fine under windows 8
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"When the hammer drops, the bullshit stops"

Once the RTL2832U SDR driver ( »sdr.osmocom.org/trac/wiki/rtl-sdr ) is working on a suitable platform (Beagleboards, Raspberry pi, etc), please try out commands like this:

rtl_fm -f 144800000 -s 22050 - | multimon -a AFSK1200 -t raw /dev/stdin