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Well, I was more talking about a general device to assist in reverse engineering various RF protocols (and that was before I found the price for this device :)

by heywire 10y ago

Well, I was more talking about a general device to assist in reverse engineering various RF protocols (and that was before I found the price for this device :) ). Now knowing the price, it puts it up with the YardStick One, which is probably out of my price range (I'm cheap). The CC110L + ESP8266 setup that I'm working with currently cost me about $12 shipped, combined (eBay as well). The selling point on using the CC11xx vs. generic rtlsdr is the scanning speed. The particular protocol that my electric and water meters speak is spread spectrum with 400kHz channel spacing and 25 channels. I'm able to park my rtlsdr on a frequency and get about 1/4 of the packets (luckily there is no change in channel during packets). I've tried scanning, but the dongles I have just aren't quick enough. The meters themselves actually use the TI chips, so I know they're up to snuff.

Radio2034 10y ago
Ah, I see. I have a HackRF and several USRPs, so I'm kinda spoiled in terms of bandwidth and capabilities. You could try combining more than one RTLSDRs into one virtual stream using GNURadio. Check this out: http://www.rtl-sdr.com/combining-the-bandwidth-of-multiple-rtl-sdrs-now-working-in-gqrx/ http://www.rtl-sdr.com/combining-the-bandwidth-of-multiple-r... The only catch is that it is not phase coherent, but if you're doing FSK or AM then that's perfectly fine.
- heywire 10y ago
  I've had a HackRF on my wishlist ever since discovering Mike's awesome SDR video series. That said, I wouldn't want to dedicate the device to the meter reading (hence my trying to pare down to the bare essentials). Funny you mention using multiple dongles, I've actually been doing just that while working out the protocol to capture as many messages as possible. Except in my case, since 2.4MHz gets me exactly 6 channels, I can just run multiple instances of my application, each looking at their own 2.4MHz chunk of spectrum. No need to truly synchronize them.

by heywire 10y ago

Radio2034 10y ago

Ah, I see. I have a HackRF and several USRPs, so I'm kinda spoiled in terms of bandwidth and capabilities. You could try combining more than one RTLSDRs into one virtual stream using GNURadio. Check this out: http://www.rtl-sdr.com/combining-the-bandwidth-of-multiple-rtl-sdrs-now-working-in-gqrx/ http://www.rtl-sdr.com/combining-the-bandwidth-of-multiple-r... The only catch is that it is not phase coherent, but if you're doing FSK or AM then that's perfectly fine.

heywire 10y ago
I've had a HackRF on my wishlist ever since discovering Mike's awesome SDR video series. That said, I wouldn't want to dedicate the device to the meter reading (hence my trying to pare down to the bare essentials). Funny you mention using multiple dongles, I've actually been doing just that while working out the protocol to capture as many messages as possible. Except in my case, since 2.4MHz gets me exactly 6 channels, I can just run multiple instances of my application, each looking at their own 2.4MHz chunk of spectrum. No need to truly synchronize them.