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Icom RP2c / Ambe decoding

Posted: Tue Mar 01, 2022 3:46 pm
by g0lgj
Hi running a Icom stack with Raspberry Pi 2 having trouble decoding AMBE stations , I can listen on my own hotspot DVRPT1 and also another repeater running a Pi-star and STM-32 Repeater Controller Kenwood TK-7180 mobiles both which decode fine.

All other stations decode fine. ID-5100 is showing L when AMBE station is transmitting.

Dont think it a peformance issue but has to be something on my stack ?

pi-star is up todate and was doing this before any upgrades etc.

Mark G0LGJ

Re: Icom RP2c / Ambe decoding

Posted: Tue Mar 01, 2022 10:07 pm
by AF6VN
To my understanding, Pi-Star and the RF boards used on them do not do any AMBE CODEC operations, they just pass encoded digital data between the network and the RF modules. AMBE encode/decode is typically done on the radio accessing the system.

HT/other/with CODEC <digitized/encoded FM modulation> hotspot/repeater <demodulated digital> Network...

Just my way of pointing out that I'm not sure what equipment is where in your setup, and what it is meant to provide at that location in the stream

Re: Icom RP2c / Ambe decoding

Posted: Wed Mar 02, 2022 8:10 am
by M1DNS
L in the eighth position is used to link. As set in the UR field.

ie xlxoooAL

Link to: xlx000 module A.

Is that what ur seeing?

If not ive never seen anything transmitting, identifying L
It might be a callsign misconfiguration in the user radio.

Otherwise might need a bit more info, in trying to understand the question ur posting. ??

Sent via smoke signals from my SM-G935F M1DNS (Admin)


Re: Icom RP2c / Ambe decoding

Posted: Wed Mar 02, 2022 9:15 am
by g0lgj
Hi
I am the repeater keeper for GB7NB it is a Icom Stack RP4000v and Icom ID-RP2c with pi-star running Raspberry Pi 2 Model B Rev 1.1 version 4.1.6

Working fine unless a remote station say via REF001C comes in using AMBE and the Audio is broken garbled.

I can listed to the same station via another repeater / Node / hotspot and Audio is fine. Using the same Radio. Tried a different radi on 7NB and same
No comments in QSO re the Audio so I am sure it is something on GB7NB

The L displayed in the ID-5100 is showing packet loss While receiving data through the Internet, some packets may be lost due to a network error

This is only ever shown on AMBE stations.

Can connect to DCS Dplus etc and no issues.
Mark G0LGJ

Re: Icom RP2c / Ambe decoding

Posted: Thu Mar 03, 2022 7:09 am
by M1DNS
Yep. The little L shown in the display. Yeah thats loss coming over the net. Agreed.

When you say ambe do you mean /ambe showing in the callsign?

I've an idea they might be using software running on a mobile phone.
Have a google search re: Droidstar.

Sent via smoke signals from my SM-G935F M1DNS (Admin)


Re: Icom RP2c / Ambe decoding

Posted: Thu Mar 03, 2022 10:52 am
by g0lgj
Hi again , yes showing AMBE in ID field. Such as min is G0LGJ /5100

Yes heard of droidstar but it does not explain why it only happends on one of the repeaters

Mark