Spontaneous Transmissions - MD-9600

[kg0rp]

I've noticed spontaneous transmissions from my MD-9600. It only happens in DMR mode, never in FM. the log example below is pretty typical. I transmit on a TG, any TG, and then I see 0 second transmissions at random times. The transmission is always tagged as RF voice transmission lost, but as can be seen from the log, the transmission does make it out and receive a response from the Brandmeister network.

Wondering if anyone else has observed this.


I: 2023-06-18 15:17:48.072 This software is for use on amateur radio networks only,
I: 2023-06-18 15:17:48.073 it is to be used for educational purposes only. Its use on
I: 2023-06-18 15:17:48.073 commercial networks is strictly prohibited.
I: 2023-06-18 15:17:48.073 Copyright(C) 2015-2020 by Jonathan Naylor, G4KLX and others
M: 2023-06-18 15:17:48.073 MMDVMHost-20210617_PS4 is starting
M: 2023-06-18 15:17:48.073 Built 16:32:57 Jun 17 2021 (GitID #9106fd6)
I: 2023-06-18 15:17:48.073 General Parameters
I: 2023-06-18 15:17:48.073 Callsign: KG0RP
I: 2023-06-18 15:17:48.073 Id: 3167478
I: 2023-06-18 15:17:48.073 Duplex: no
I: 2023-06-18 15:17:48.073 Timeout: 240s
I: 2023-06-18 15:17:48.073 D-Star: disabled
I: 2023-06-18 15:17:48.073 DMR: enabled
I: 2023-06-18 15:17:48.073 YSF: disabled
I: 2023-06-18 15:17:48.073 P25: disabled
I: 2023-06-18 15:17:48.073 NXDN: disabled
I: 2023-06-18 15:17:48.073 POCSAG: disabled
I: 2023-06-18 15:17:48.073 FM: disabled
I: 2023-06-18 15:17:48.073 Modem Parameters
I: 2023-06-18 15:17:48.074 Port: /dev/ttyACM0
I: 2023-06-18 15:17:48.074 Protocol: uart
I: 2023-06-18 15:17:48.074 RX Invert: no
I: 2023-06-18 15:17:48.074 TX Invert: yes
I: 2023-06-18 15:17:48.074 PTT Invert: no
I: 2023-06-18 15:17:48.074 TX Delay: 100ms
I: 2023-06-18 15:17:48.074 RX Offset: 0Hz
I: 2023-06-18 15:17:48.074 TX Offset: 0Hz
I: 2023-06-18 15:17:48.074 RX DC Offset: 0
I: 2023-06-18 15:17:48.074 TX DC Offset: 0
I: 2023-06-18 15:17:48.074 RF Level: 100.0%
I: 2023-06-18 15:17:48.074 DMR Delay: 0 (0.0ms)
I: 2023-06-18 15:17:48.074 RX Level: 50.0%
I: 2023-06-18 15:17:48.074 CW Id TX Level: 50.0%
I: 2023-06-18 15:17:48.074 D-Star TX Level: 50.0%
I: 2023-06-18 15:17:48.074 DMR TX Level: 50.0%
I: 2023-06-18 15:17:48.074 YSF TX Level: 50.0%
I: 2023-06-18 15:17:48.074 P25 TX Level: 50.0%
I: 2023-06-18 15:17:48.074 NXDN TX Level: 50.0%
I: 2023-06-18 15:17:48.074 POCSAG TX Level: 50.0%
I: 2023-06-18 15:17:48.074 FM TX Level: 50.0%
I: 2023-06-18 15:17:48.074 TX Frequency: 446790000Hz (446790000Hz)
I: 2023-06-18 15:17:48.075 Use COS as Lockout: no
M: 2023-06-18 15:17:48.109 Opening the MMDVM
I: 2023-06-18 15:17:50.171 MMDVM protocol version: 1, description: OpenGD77_HS v0.1.15 GitID #UNKNOWN (Radio:DM-1701, Mode:MMDVM)
I: 2023-06-18 15:17:50.191 Display Parameters
I: 2023-06-18 15:17:50.191 Type: OLED
I: 2023-06-18 15:17:50.596 DMR Network Parameters
I: 2023-06-18 15:17:50.596 Type: Gateway
I: 2023-06-18 15:17:50.596 Address: 127.0.0.1
I: 2023-06-18 15:17:50.596 Port: 62031
I: 2023-06-18 15:17:50.596 Local: 62032
I: 2023-06-18 15:17:50.596 Jitter: 360ms
I: 2023-06-18 15:17:50.596 Slot 1: disabled
I: 2023-06-18 15:17:50.596 Slot 2: enabled
I: 2023-06-18 15:17:50.596 Mode Hang: 20s
I: 2023-06-18 15:17:50.597 Info Parameters
I: 2023-06-18 15:17:50.597 Callsign: KG0RP
I: 2023-06-18 15:17:50.597 RX Frequency: 446790000Hz
I: 2023-06-18 15:17:50.597 TX Frequency: 446790000Hz
I: 2023-06-18 15:17:50.597 Power: 1W
M: 2023-06-18 15:17:50.597 DMR, Opening DMR Network
I: 2023-06-18 15:17:50.598 Opening UDP port on 62032
I: 2023-06-18 15:17:50.598 RSSI
I: 2023-06-18 15:17:50.598 Mapping File: /usr/local/etc/RSSI.dat
I: 2023-06-18 15:17:50.641 Loaded 14 RSSI data mapping points from /usr/local/etc/RSSI.dat
I: 2023-06-18 15:17:50.641 DMR Id Lookups
I: 2023-06-18 15:17:50.641 File: /usr/local/etc/DMRIds.dat
I: 2023-06-18 15:17:50.641 Reload: 24 hours
I: 2023-06-18 15:31:02.584 Loaded 240486 IDs to lookup table - /usr/local/etc/DMRIds.dat
I: 2023-06-18 15:31:02.585 DMR RF Parameters
I: 2023-06-18 15:31:02.585 Id: 3167478
I: 2023-06-18 15:31:02.585 Color Code: 1
I: 2023-06-18 15:31:02.585 Self Only: yes
I: 2023-06-18 15:31:02.585 Embedded LC Only: no
I: 2023-06-18 15:31:02.585 Dump Talker Alias Data: yes
I: 2023-06-18 15:31:02.585 Prefixes: 0
I: 2023-06-18 15:31:02.585 Call Hang: 3s
I: 2023-06-18 15:31:02.585 TX Hang: 4s
I: 2023-06-18 15:31:02.585 Mode Hang: 20s
I: 2023-06-18 15:31:02.585 OVCM: off
I: 2023-06-18 15:31:02.585 DMR Roaming Beacons Type: off
I: 2023-06-18 15:31:02.589 Started the DMR Id lookup reload thread
I: 2023-06-18 15:31:02.716 Interfaces Info
I: 2023-06-18 15:31:02.718 IPv4: lo:127.0.0.1
I: 2023-06-18 15:31:02.718 IPv4: wlan0:192.168.1.70
I: 2023-06-18 15:31:02.718 Default interface is : wlan0
I: 2023-06-18 15:31:02.718 IP to show: wlan0:192.168.1.70
M: 2023-06-18 15:31:02.718 MMDVMHost-20210617_PS4 is running
M: 2023-06-18 15:36:16.876 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 15:36:27.556 DMR Slot 2, received RF end of voice transmission from KG0RP to 4000, 10.8 seconds, BER: 0.9%, RSSI: -124/-74/-123 dBm
M: 2023-06-18 15:36:31.000 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 15:36:31.784 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 16:41:35.432 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 16:41:45.331 DMR Slot 2, received RF end of voice transmission from KG0RP to 4000, 10.1 seconds, BER: 0.8%, RSSI: -124/-78/-123 dBm
M: 2023-06-18 16:41:46.997 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 16:41:47.185 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 16:41:48.762 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 16:41:49.482 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 16:41:51.514 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 16:41:52.300 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 16:51:33.948 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 16:51:34.013 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 16:51:38.308 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 16:51:39.103 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 16:57:33.285 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 16:57:33.339 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 16:57:37.594 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 16:57:38.318 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 17:02:26.759 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 17:02:26.939 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.1 seconds, BER: 2.1%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 17:02:31.359 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 17:02:32.083 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:08:37.582 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:08:47.900 DMR Slot 2, received RF end of voice transmission from KG0RP to 4000, 10.4 seconds, BER: 1.0%, RSSI: -124/-124/-124 dBm
M: 2023-06-18 18:08:51.332 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 18:08:52.062 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:09:48.776 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:09:59.097 DMR Slot 2, received RF end of voice transmission from KG0RP to 4000, 10.4 seconds, BER: 0.8%, RSSI: -124/-124/-124 dBm
M: 2023-06-18 18:10:02.555 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 18:10:03.290 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:34:52.057 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:35:00.215 DMR Slot 2, received RF end of voice transmission from KG0RP to 4000, 8.3 seconds, BER: 0.7%, RSSI: -124/-106/-123 dBm
M: 2023-06-18 18:35:03.629 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 18:35:04.372 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:42:31.599 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:42:31.673 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 18:42:35.972 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 18:42:36.759 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:46:47.812 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:46:47.887 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 18:46:52.296 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 2023-06-18 18:46:53.079 DMR Slot 2, received network end of voice transmission from 4000 to KG0RP, 1.0 seconds, 0% packet loss, BER: 0.0%
M: 2023-06-18 18:52:09.971 DMR Slot 2, received RF voice header from KG0RP to 4000
M: 2023-06-18 18:52:10.046 DMR Slot 2, RF voice transmission lost from KG0RP to 4000, 0.0 seconds, BER: 0.0%, RSSI: -43/-43/-43 dBm
M: 2023-06-18 18:52:14.312 DMR Slot 2, received network voice header from 4000 to KG0RP
M: 202

[G4EML]

I don't think this has been reported before.

Are you sure you don't have VOX turned on?

Can you use another radio to listen using FM just to confirm that the 9600 really is transmitting. It is not unheard of for MMDVM to generate 'ghost' signals.

Colin G4EML

[VK3KYY]

AFIK 4000 is the network disconnect TG, and some networks send this automatically after a specific time

Is your radio set to TG 4000

Did you actually see the radio transmit for 10 seconds each time?

[ok1pt]

AFIK 4000 is the network disconnect TG, and some networks send this automatically after a specific time

Is your radio set to TG 4000

Did you actually see the radio transmit for 10 seconds each time?

Hi!
I think that the long RF transmissions (8 - 10 seconds) are regular transmissions done by the user. But he clearly writes that there are 0.0 second long transmissions, which are marked as "lost". And there is also written that they appear on the same TG as the previous regular transmissions. So, my understanding is that in this log you can see a mix of regular transmissions on TG4000 (probably for testing purposes, as this TG is not distributed by the network) and spurious transmissions with zero length marked as lost, which is the problem the user is reporting.
With regards, Pavel
73

[kg0rp]

Pavel is correct. The longer transmissions were tests where I keyed the mic. The short 0 second transmissions are the spontaneous transmissions. Yes, I've seen the 0 second transmissions first hand. All I have to do is leave the volume on the radio turned up loud enough to hear it in the other room and I'll sporadically hear the response "unlinked" occur at totally random times. I'm beginning to think it might be a hardware problem on this radio, but I have no way of proving it.

The radio is set to TG4000. To demonstrate the problem, I reboot everything; everything being the 9600, the Pi*, and the 1801that acts as the hotspot. Once everything is settled down, I make a 10 second transmission on TG4000 and then leave it alone. Sure enough, the spurious transmissions start up after a period of time that varies. As I stated earlier, the transmissions appear to be totally random.

It never occurs in FM mode.

Since no one else has reported having a similar issue, I'm marking this down to a probable hardware problem.

Tom - KG0RP

[F1RMB]

Hi,

Sorry for the stupid question, but what is your hardware version, and does the installed firmware matches it (you can see it in Firmwre info screen) ?


Cheers.
---
Daniel

[G4EML]

Hearing the 'Unlinked' message does not confirm the radio is actually transmitting. It just means the network thinks that you have. As I said before MMDVM has been known to generate ghost signals without actually receiving anything.

You are using a simplex hotspot so there is no handshaking with the radio. The spurious transmissions would occur even with the hotspot off.

If you have a second radio set it to FM and listen to the 9600 with the hotspot turned off. You should hear the buzz of the DMR transmission Repeat your test and see if you can confirm the radio is actually transmitting on its own.

Colin G4EML.

[F1RMB]

Maybe you can also, if you have one, use a MMDVM hotspot instead of the 1701 you're using, to see if it's not the 1701 modem that sends such frame to MMDVMHost.

Cheers
---
Daniel

[kg0rp]

Colin (G4EML) was spot on suggesting monitoring with a radio set up for FM. I listened in with my HT tuned to the hotspot frequency, and sure enough, I heard only the network response come back, but nothing went out from the 9600. The culprit is either the 1700 or the P*0. My money is on the Pi*0, antique that it is.

I'll try it with the radio enabled in the Pi* just to eliminate the 1700 from the picture.

Anyway, thanks to everyone for the suggestions, I think this can be closed out as not a 9600 related issue.

Tom - KG0RP

[G4EML]

Thanks for the feedback Tom.

From when I was involved in the network administration I do remember such 'Ghost' transmission occurring sometimes. I can't remember the exact cause though. I don't know if you can easily update your hotspot firmware, but if that is possible then it might be worth doing.

Colin G4EML