Issue with CTCSS decoding.

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G4KWT
Posts: 4
Joined: Fri Nov 27, 2020 6:16 pm

Issue with CTCSS decoding.

Post by G4KWT » Wed Dec 23, 2020 1:50 pm

Issue with CTCSS decoding.

Firmware Version: 07:32:36 Dec 2020 [ b36ef62 ]

Test Equipment: Marconi Communications Service Monitor 2945

Test Signal: 433.775MHz, -110dBm, CTCSS 118.8Hz @ 250Hz deviation.

GD77 Radio programmed to 433.775MHz, FM mode with 25kHz bandwidth.
Rx CTCSS set to 118.8Hz.

Issue: If the test signal's CTCSS tone modulation is switched
off and back on again the tone squelch on the radio closes
but does not re-open. It appears to have latched in the
closed state. This latching is reset if the carrier is
switched off and back on again.

Denis G4KWT

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F1RMB
Posts: 2518
Joined: Sat Nov 16, 2019 5:42 am
Location: Grenoble, France

Re: Issue with CTCSS decoding.

Post by F1RMB » Wed Dec 23, 2020 2:26 pm

G4KWT wrote:
Wed Dec 23, 2020 1:50 pm
Issue with CTCSS decoding.

Firmware Version: 07:32:36 Dec 2020 [ b36ef62 ]

Test Equipment: Marconi Communications Service Monitor 2945

Test Signal: 433.775MHz, -110dBm, CTCSS 118.8Hz @ 250Hz deviation.

GD77 Radio programmed to 433.775MHz, FM mode with 25kHz bandwidth.
Rx CTCSS set to 118.8Hz.

Issue: If the test signal's CTCSS tone modulation is switched
off and back on again the tone squelch on the radio closes
but does not re-open. It appears to have latched in the
closed state. This latching is reset if the carrier is
switched off and back on again.

Denis G4KWT
I suggest you to re-test with the next beta release.
Out of curiosity, in which real life condition a sub-tone is not sent continuously ?

---
Daniel

OH1E
Posts: 96
Joined: Sat Nov 16, 2019 8:59 am

Re: Issue with CTCSS decoding.

Post by OH1E » Thu Dec 24, 2020 11:00 pm

F1RMB wrote:
Wed Dec 23, 2020 2:26 pm
I suggest you to re-test with the next beta release.
Out of curiosity, in which real life condition a sub-tone is not sent continuously ?
---
Daniel
case 1. using svxlink and use setting send tone only when traffic(example: TX_CTCSS=SQL_OPEN). repeater ptt will stay on, but subtone only sent with traffic. so between user change there is no tone at all(to mute all static). commonly used setting.
case 2. be portable/mobile on edge of repeater might cause this when signal is low with a lot static with it.

riku

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F1RMB
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Location: Grenoble, France

Re: Issue with CTCSS decoding.

Post by F1RMB » Fri Dec 25, 2020 6:14 am

Riku wrote:
Thu Dec 24, 2020 11:00 pm
F1RMB wrote:
Wed Dec 23, 2020 2:26 pm
I suggest you to re-test with the next beta release.
Out of curiosity, in which real life condition a sub-tone is not sent continuously ?
---
Daniel
case 1. using svxlink and use setting send tone only when traffic(example: TX_CTCSS=SQL_OPEN). repeater ptt will stay on, but subtone only sent with traffic. so between user change there is no tone at all(to mute all static). commonly used setting.
case 2. be portable/mobile on edge of repeater might cause this when signal is low with a lot static with it.

riku
I completely understand case #1, but case #2 has nothing to do with this, it's just the signal that going up and down the squelch level (or even noise floor).

G4KWT
Posts: 4
Joined: Fri Nov 27, 2020 6:16 pm

Re: Issue with CTCSS decoding.

Post by G4KWT » Sat Dec 26, 2020 4:09 pm

I suggest you to re-test with the next beta release.
Out of curiosity, in which real life condition a sub-tone is not sent continuously ?
---
Daniel
Hi Daniel

I will try that.

Our local 70cm repeater, GB3BN, has a remote EchoLink. Transmission from the remote EchoLink
station is inhibited while the repeater is transmitting its CTCSS tone. The Repeater drops its CTCSS tone
at the end of an RF station's over, and after the morse 'T', to allow the EchoLink remote connected
station to transmit (reply) through the repeater.

My curiosity would be - why would you latch the CTCSS tone squelch in the 'off' state when the CTCSS tone
dissappears from the signal? The receiver muting should simply follow the presence/absence of the CTCSS tone,
with possibly a small hang time to allow for a weak/fluttery signal.

Denis G4KWT

G4EML
Posts: 919
Joined: Sat Nov 16, 2019 10:01 am

Re: Issue with CTCSS decoding.

Post by G4EML » Sat Dec 26, 2020 5:15 pm

I was surprised to see this report because the radio certainly didn't have this fault in the past.

I have just checked and it appears to have been introduced with the DEC 20th release. The previous Nov 12th release is working as it should.

Due to the policy of not releasing the current source I can't investigate any further.

Colin G4EML

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F1RMB
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Location: Grenoble, France

Re: Issue with CTCSS decoding.

Post by F1RMB » Sat Dec 26, 2020 5:37 pm

Hi,

Due to one of the big cleanups, this bug was introduced (while fixing another one).
The fix is ready and will be part of the next release.


Cheers.
---
Daniel

VK3KYY
Posts: 7481
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Issue with CTCSS decoding.

Post by VK3KYY » Sun Dec 27, 2020 6:42 am


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EB3AM
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Re: Issue with CTCSS decoding.

Post by EB3AM » Mon Dec 28, 2020 8:46 am

G4EML wrote:
Sat Dec 26, 2020 5:15 pm
Due to the policy of not releasing the current source I can't investigate any further.

Colin G4EML
Please.
What did I miss? :oops:

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