decoding problem

[Alpha-SG31]

Hello,
There is something I don't understand: I have an RTL-SDR running with PagerMonitor and another RTL-SDR running elsewhere with multimon-ng same antenna, yet PagerMonitor decodes only half the transmissions or produces errors.
In the log, I see it interpreting an alphanumeric frame as numeric.

Here is what PagerMonitor decoding

POCSAG512: Address: 310053 Function: 0 Numeric: ] 2267.9 928283]17.9 5673-142[77-9]9]2U 144]23846029[UU]5]938]50291-070.12.U -]4UU144].386.4[039U 0.95 .63U.186.1].U-U 4[2U 5]5]619U -.1]UU--]4UU[ 5]930000

and multimon-ng are decoding.

POCSAG512: Address: 310053 Function: 0 Alpha: NXS Secure message (teleA) / 5 Rue de Tran 31000 Toulouse
"This is not an original message, but an example."

Some messages are not being received by Pagermonitor.

What is the problem?
Do you think this can be fixed?

Thanks.

[Dj3ky]

Hello,
did you installed over docker or native with install.sh on bare-metal?

[Alpha-SG31]

Hello,
Native with install.sh.

[Dj3ky]

This should proboably be problem with your settings or antenna. Please check frequency, gain (maybe put higher than you have),... Also check Settings -> Feed Filter -> Message type that you have All or Alpha only.

[Alpha-SG31]

The settings are correct, i’ve already checked and the antenna is the same for both SDRs.
It decodes messages in that format.

on Pagermonitor POCSAG512: Address: 319900 Function: 2 Alpha: NX ANNULATION - Mission - Personne malade - VSAV 02 - EQ

on Multimon-NG POCSAG512: Address: 319900 Function: 2 Alpha: NX ANNULATION - Mission - Personne malade - VSAV 02 - EQ

The only problem arises when there is a postal address.

[Dj3ky]

Can you check this: In SDR setting on Multimon-ng part check CHARSET (-C). Did you put here FR
(proboably you are from French)?
And after that restart server or client.

[Alpha-SG31]

Yes, I'm French; I think I've already tried that, but I'll give it a go.

[Dj3ky]

Is it working now?

[Alpha-SG31]

Hello,
No, the FR hasn't changed anything; as soon as there's a postal address, it doesn't decode it.

[Dj3ky]

Can you give me one batch of messages one that is ok (from your system) and the same one that is wrong decoded (from pagermonitor) that I can compare and check.

[Alpha-SG31]

It's in the first message.

Here is what PagerMonitor decoding

POCSAG512: Address: 310053 Function: 0 Numeric: ] 2267.9 928283]17.9 5673-142[77-9]9]2U 144]23846029[UU]5]938]50291-070.12.U -]4UU144].386.4[039U 0.95 .63U.186.1].U-U 4[2U 5]5]619U -.1]UU--]4UU[ 5]930000

and multimon-ng are decoding.

POCSAG512: Address: 310053 Function: 0 Alpha: NXS Secure message (teleA) / 5 Rue de Tran 31000 Toulouse
"This is not an original message, but an example."

I have modified the original message for privacy reasons; if you need the actual message to avoid skewing the results, I can email it to you. Just provide your email address or send me a message at Alpha31@rescueteam.com.

[Dj3ky]

Hmm that souds really weird. What dongle do you have and which version, do you have usb hub or extension cable maybe for SDR, on what hardware you are running this server? Can you also printscreen settings of SDR?