Running two RTL-SDR Blog V3, coverage question

KD0FEO

Wright County, MN
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I just bought two RTL-SDR Blog V3 and noticed that I have quite a gap in the frequencies, would it be possible to use one dongle to monitor the stations grouped together and another to just catch the 858.3625? I was able to set up SDR Trunk with aliases and whatnot and got it broadcasting to Broadcastify monitoring 851.175mhz - 853.575 but noticed a few errors which I'm guessing it can't access the 858. I'm not interested in monitoring anything but one site and like 2 talk groups but the site is so busy that I often get maximum channels, etc. I've gotten this far on my own, first time experimenting with SDR.

Would what I'm requesting even be achievable? If so, can someone point me in a good direction?


freq.png
 

dave3825

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I just bought two RTL-SDR Blog V3 and noticed that I have quite a gap in the frequencies, would it be possible to use one dongle to monitor the stations grouped together and another to just catch the 858.3625?


851.175 to 853.575 is exactly 2.4. Not sure what the actual usable bandwidth is on that dongle but you could try setting the sample rate in SDRT to 2.56.

That 858 freq would require the second dongle to be parked in that range.


851.175mhz - 853.575 but noticed a few errors which I'm guessing it can't access the 858.
What do those errors say? No tuner available?


not interested in monitoring anything but one site and like 2 talk groups but the site is so busy that I often get maximum channels
Its a phase 1 system with 12 freqs total. Increase the Max Traffic Channels.

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KD0FEO

Wright County, MN
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851.175 to 853.575 is exactly 2.4. Not sure what the actual usable bandwidth is on that dongle but you could try setting the sample rate in SDRT to 2.56.

That 858 freq would require the second dongle to be parked in that range.



What do those errors say? No tuner available?



Its a phase 1 system with 12 freqs total. Increase the Max Traffic Channels.

View attachment 153334
Channel Start Rejected - Phase 1 Channel Grant (Something with a group call)
Deny affiliation group: 0 (Local) Announcement Group:0

I have not seen the tuner unavailable error yet, just the two following above. Thank you for the max channels thing, I know I've looked at that before and wasn't able to put two and two together. I know it's possible to run two dongles but even with the 858 it would still require the control frequencies which is way beyond the 2.4mhz that each dongle handles?
 
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dave3825

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Channel Start Rejected - Phase 1 Channel Grant (Something with a group call)
Deny affiliation group: 0 (Local) Announcement Group:0
First one would be something with SDRT. Second one looks like stuff being broadcast over the control channel.
 

KD0FEO

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First one would be something with SDRT. Second one looks like stuff being broadcast over the control channel.
I just plugged in my second dongle and it appears the program is smart enough and parked the second dongle on the higher frequency by itself, I guess that is problem solved! It's not the exact frequency of 858.3625 but all of the errors have disappeared and events are showing that it's getting voice. I guess programing in all of the frequencies on the other dongle relayed that information and the program knew what it had to do to make it work! Amazingly simple, thank you for the help Dave!

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1703227905163.png
 

dave3825

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You may at some point have to assign that dongle to a dummy freq in the 858 range and assign the other to the rest of the system and set them to autostart.
 

KD0FEO

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