To confirm, delete the alt ctrl, change max traffic channels to 10 and change LSM to C4FM? (i'm not seeing "voice channels") Thank you
SDRTrunk SDRtrunk error message
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To confirm, delete alt control, reduce traffic channels to 10? (i dont see voice channels) and switch to C4FM? What happens if the data goes to 854.7375 again? the last time it didn't switch over. Thank you
I'm on the road but I would think if you delete the alt control channels, and the cc rotates to an alt cc that's not programmed, it will not have anything to lock onto to and decode.
The advice you are following is flawed. The Manatee Simulcast site is simulcast, thus should be configured as LSM. This is a Motorola system, which means you should be entering all 4 control channels for the Manatee site in your configuration to allow for control channel rolling - which should not happen very often with Motorola system. In your previous screen shots, it looks like your gain is set too high - try backing it down incrementally. What county are you monitoring from - Manatee or Sarasota? Only try to monitor the site that covers the area that you are monitoring from - this will "save" some turn resources. Or you could use single Airspy which alleviates bandwidth headaches almost entirely.
How do I adjust "gain"? I am in Sarasota. I have 1 dongle for the Sarasota zone and 2 for the Manatee zone. The Sarasota zone works fine. The signal for Manatee is somewhat marginal but I have a beam up high pointed that direction. I like to have both zones because not all traffiic comes over both of them. Can you tell me more about Airspy? I have heard of it but am not familiar with it. I tried adding a 3rd donagle to Manatee using a strideburg splitter for the antenna but the noise floor increased. Thank you
The "somewhat marginal" signal should explain some of your issues with Manatee and losing the control channel. Control channels on Motorola systems rarely change, so I'm guessing your received signal quality / strength is the actual issue. Gain is adjusted using the dropdown list labeled Master in the Gain Control section accessed via the tuners tab. Each SDR (Tuner)'s gain can be adjusted individually. Speaking generally, you could lower the gain on the tuners assigned to Sarasota, but increase the gain for the tuners assigned to Manatee. You may need to set up two antennas: one for Sarasota and one for Manatee.
The Sarasota dongle has its own rubber duck since it doesnt need any help. The two dongles for Manatee are on the beam I mentioned with a sma splitter. I checked the gain. It is set to 327 on all three...there is an automatic and various numbers from 0 to 495.
Airspys have a broader bandwidth coverage, either 6 MHz for the Mini or 10 MHz for the R2 depending on the model. Usable bandwidth is roughly 80% of that, so 4.6 MHz and 8 MHz respectively (usable bandwidth for RTL or Nooelec SDRs is 80% of 2.4 MHz or 1.9 MHz). A single Airspy Mini could cover the Sarasota Simulcast site, or a single Airspy R2 could just about cover both sites - except you should probably be using separate antennas and SDRs if you want to receive both sites.
Thank you for that info. I started fiddling with the gain but didn't notice any difference on the scope unless I wasnt doing it right, not sure LNA and VNA are. The Manatee zone has frequencies from 854.3375 to 859.7875 (slightly more than 5 MHZ). The Sarasota zones runs 851.3875 to 853.675 (less than 2.5 MHZ so 1 dongle is fine). BTW I am using nooelec dongles.
I'll posit a theory that once you Manatee signal degrades, you lose the control channel and the SDR originally assigned to the Manatee control channel becomes a pool resource that gets assigned a Sarasota voice channel. Somehow you will need to improve your reception of the Manatee site by increasing the gain of the SDR(s) assigned to it, pointing the antenna at a different direction, raising it, installing better antenna cable or a TTA - or move, lol.
I don't think I'm losing CC...except for the one time it changed from 855.3875 to 854.7375 for about a day. So to increase the gain do I up the LNA number or the VGA number-or both?
BTW Sarasota is permanently assigned to dongle 1...Manatee is free to use 2 & 3 as it sees fit neither are assigned.
You will need to experiment with the gains - every situation is more or less unique.
What works for me, turn master down all the way. Tune to the control channel without starting the dongle. While watching the spectrum, increase the master to where the signal on the cc reaches its highest peak, and you should also see the noise floor just start to rise. That's where you want to be. Right at highest peak and where the floor just starts to rise.
So when you lose the Manatee control channel for whatever reason, that dongle becomes available for assignment by the Sarasota control channel. This is why an Airspy might be a solution for the Manatee site - it can tune to any Manatee control channel if properly configured.
No I don't think so...Sarasota is assigned and always stays with Dongle 1. Dongles 2 and 3 are not assigned. Should I assign one of them to Manatee? Theres two separate zones running simultaneously.
I'm not sure you are understanding the logic. "Unassigned" dongles when not doing anything can be freely assigned a voice channel as needed by the other SDR playing Sarasota. If you "assign" one SDR to the Manatee primary control channel (the cch that is almost always used) that can help somewhat, but if the control channel rolls to a control channel outside its bandwidth, there may ar may not be a SDR resource available. What do you mean by "two separate zones running simultaneously"? If you mean two sites are playing simultaneously, yes I see that and is the basis of my advice.
ToddWilkinson
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I ONLY USE THE CONTROL CHANNEL, give in 10 voice slots, let er buck, my system can be heard at Wadena County Public Safety in Wadena MN, mines setup that way, I use 1 tower and that's all I need, it gets insane at times lol.
If the control channel ever changes, and some do, your sdrtrunk will be sitting there not decoding anything.
What do you mean by 10 voice slots? THe only thing I see is max traffic channels which I have 17 which the number of channels in the zone.
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