PI-STAR Looping

General support for the Pi-Star System
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Joined: Thu Jun 14, 2018 5:54 pm

PI-STAR Looping

Post by W8DSB » Tue Jan 29, 2019 3:03 am

@Andy, lately there have been a lot of hotspots getting into loops on high profile talkgroups like TAC310. I just had the same issue on our local clubs TG because one user forgot to turn off his truck hotspot when he pulled up at home. We as a club just built 20 jumbospots for a club project, all is great until the Saturday morning breakfast when everyone comes together to eat :) There should be a way to fix this if we all work together.

I first thought we could split the colorcodes but mapping it on paper proves this is not a doable solution. I think, however we could split the frequency. If you are lucky enough to own a full duplex hotspot you can run them next to each other because they can't hear each other. If you run a half dulplex hotspot then two of them will transmit and receive on the same freq creating the loop.

I understand from asking before that some hardware modems will not take a different tx and rx freq in the modem however why can't pi-star push a rx freq when listening and push a tx freq when transmitting working around the modem limitations. If we could do this then we could work around most looping issues.

Yes we could all run different freq within our club however with 20 jumbospots, a DMR 40 watt repeater running pi-star on a tower. I only want to maintain ONE codeplug for all.

What are the thoughts on this?

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Re: PI-STAR Looping

Post by MW0MWZ » Tue Jan 29, 2019 7:38 pm

OK here goes...

1. So long as the chosen modem on the config page is NOT a "dual" modem, you should be able to configure them for split, if that is not the case, ensure they have the correct mmdvm_hs firmware (and not mmdvm_hs_dual on them. The exception to the rule here is the DVMega boards, they really don't like split.

2. Hotspot "Node Type" in the General config should be private unless you are a repeater keeper or have a good reason not to, this will lock the hotspot to your own DMR ID/Callsign on all modes - this is one of the very things it is designed to guard against, I know that while this is a licence requirement in the UK, it may not apply in the US - but you are seeing first hand why its not so crazy :)

Start with those and see if that improves things for you....

73 de MW0MWZ

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