New GD77 and MD9600 Beta firmware June 19th 2022

S58SMS
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by S58SMS » Mon Jul 18, 2022 10:05 am

Do you have any email, to send a video to you?

W8LDO
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by W8LDO » Mon Jul 18, 2022 2:58 pm

G4EML wrote:
Mon Jul 18, 2022 9:49 am
From your description it sounds like the timeslot detection is occasionally failing. It does not seem to be a common occurrence and so the cause might be difficult to find. It may depend upon the number of a DMR channels being scanned, the amount of activity on the scanned channels, the order of the channels.

You say it only happens when scanning but that may be because scanning puts a heavy load on the radio. As you suggested you could try lowering the scanning speed.

Until we can come up with a repeatable scenario it will be difficult to fault find.

Maybe you can continue to do some testing. Try creating a new zone and only including a few repeaters with high activity, then scan that zone to see if the problem occurs. Then possibly change the channels to ones that have less activity. Any clues as to what may be causing your problem would be helpful.

Colin G4EML
Thanks Colin for the post. I am still playing with speeds on the scan to see what the highest speed can be optained without the issue. Will Make new post if I find a speed that will work without the issue. I use scan alot and I am aware some never scan. Made the post for awareness. Thanks to the team that make this firmware possible. Great job!

G4EML
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by G4EML » Mon Jul 18, 2022 4:55 pm

The local RF environment has a big effect as well. Here I can only hear a few DMR repeaters and none of them are busy. It’s very rare to hear both timeslots in use at the same time. So trying to reproduce reports such as yours is difficult.

Colin.

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F1RMB
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by F1RMB » Mon Jul 18, 2022 6:21 pm

Since I never had a bad timeslot detection here, I'm still a bit doubtful because the TS detection code is quite picky.

Are you sure you don't have a contact with TS override set ?
Have you double checked everything ?

Cheers.
---
Daniel

W8LDO
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by W8LDO » Tue Jul 19, 2022 3:14 am

F1RMB wrote:
Mon Jul 18, 2022 6:21 pm
Since I never had a bad timeslot detection here, I'm still a bit doubtful because the TS detection code is quite picky.

Are you sure you don't have a contact with TS override set ?
Have you double checked everything ?

Cheers.
---
Daniel
Its the same audio from the opposite time slot, just sounds distorted. Push the star button on mic to change time slots and it clears right up. Hit the star key again it goes quiet like the time slot filter is working correctly again. I will be scanning listening to for example time slot 1 and can hear time slot two after scan stops distorted while on time slot 1. Push the star key and engage time slot two and the audio clears up. Go back to time slot 1 and hear nothing again, while still receiving signal on the meter for time slot 2.

VK3KYY
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by VK3KYY » Tue Jul 19, 2022 3:22 am

For duplex repeaters the signal meter reading is not per TS, becuase repeaters transmit continuously on both TS even if there is no traffic on one of the TS.

Only simplex hotspots and simplex transmissions from other radios, does the firmware need to synchronise with the DMR frame pulses to sample the RSSI at the correct time.

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F1RMB
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by F1RMB » Wed Jul 20, 2022 9:37 am

gavalar wrote:
Wed Jul 20, 2022 8:53 am
i cannot open bin files for some reason is there another format avilble please
http://opengd77.com/viewtopic.php?f=5&t ... 763404c8bb

G4EML
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by G4EML » Wed Jul 20, 2022 11:24 am

Linkford...

Thanks for the explanation. From what you describe there certainly appears to be something wrong. The fact that you hear distorted audio tends to indicate it is not simply a timeslot detection issue. Switching timeslots with the star key will reset the decoding which is probably why it clears the audio for you.

I do remember hearing something similar during the development of the firmware. However I have not heard it recently and can't remember exactly what the cause was.

However as mentioned before this may be difficult to track down. Any experiments you can do would be helpful, especially if you can find a repeatable way of reproducing the problem.

Colin G4EML

W8LDO
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by W8LDO » Wed Jul 20, 2022 12:26 pm

G4EML wrote:
Wed Jul 20, 2022 11:24 am
Linkford...

Thanks for the explanation. From what you describe there certainly appears to be something wrong. The fact that you hear distorted audio tends to indicate it is not simply a timeslot detection issue. Switching timeslots with the star key will reset the decoding which is probably why it clears the audio for you.

I do remember hearing something similar during the development of the firmware. However I have not heard it recently and can't remember exactly what the cause was.

However as mentioned before this may be difficult to track down. Any experiments you can do would be helpful, especially if you can find a repeatable way of reproducing the problem.

Colin G4EML
The Distorted audio is the same conversation as what is being broadcasted on the opposite time slot. It sounds like bleed over. when i switch time slots and it clears up, because i am actually hearing the conversation on the right time slot. go back to the original time slot where the audio was distorted and hear nothing, just a signal on the meter. It appears when i do the switch the time slot filter functions properly again. Its like the scan catches the audio from the talk group before the filter activates properly.

VK3KYY
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Re: New GD77 and MD9600 Beta firmware June 19th 2022

Post by VK3KYY » Wed Jul 20, 2022 11:35 pm

What is the callsign of the repeater you are listening two?

Do you know what hardware it uses, specifically does it use commercial hardware e.g. Motorola or is using non commercial MMDVM hardware?

If its not a ham radio repeater, its possible it had some from of basic encryption, which causes some partial audio decode but not complete decode.

If it is a non ham repeater, you can try turning off the CRC check, as we think some commercial repeaters deliberately send invalid CRC data with the transmission so that it can't be listened to

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