AR-DV1 DMR BUZZING

[G8OEO]

Just got hold of a used DV1 and I’m not too happy with DMR reception. The firmware is 2102 if that has any bearing on things.

The start of a good strong local DMR transmission (which is fine when received on an Anytone handheld ) frequently sounds chopped or “Dalek-like” then smooths out after a second or two. Otherwise the audio quality is good after it settles down.

I’ve transferred to a known good 12V power supply just in case the unit was getting something dodgy from the AOR brick but it makes no difference.
Also tried varying the signal strength by alternating between an external discone and a short whip.

Would it be a good idea to roll back the firmware?

 

[palmerjrusa]

Just got hold of a used DV1 and I’m not too happy with DMR reception. The firmware is 2102 if that has any bearing on things.

The start of a good strong local DMR transmission (which is fine when received on an Anytone handheld ) frequently sounds chopped or “Dalek-like” then smooths out after a second or two. Otherwise the audio quality is good after it settles down.

I’ve transferred to a known good 12V power supply just in case the unit was getting something dodgy from the AOR brick but it makes no difference.
Also tried varying the signal strength by alternating between an external discone and a short whip.

Would it be a good idea to roll back the firmware?

I know exactly what you mean.

Haven't used my AR-DV1 in a while but DMR transmissions on my AR-DV10 exhibit exacty the same characteristics.

 

[G8OEO]

That’s a bit worrying.
Just to clarify I’m not talking about a short burst of FM demodultor noise before the radio realises it’s a DMR signal and starts decoding.
The memory channels doing this are all fixed to DMR mode rather than AUTO.

 

[G8OEO]

After playing around this morning selecting slot numbers it’s now starting to look like slot1 comms are OK and the buzzing may only be when slot2 stuff is being received. Very strange behaviour which is making me wonder again if it’s a bug in this firmware version.

 

[G8OEO]

Sorry to harp on about this but here's a link to a very short .wav file for anyone interested.

https://www.pontrep.uk/ardv1.wav

Have now updated to latest firmware 2205A and still the same.

 

[palmerjrusa]

After playing around this morning selecting slot numbers it’s now starting to look like slot1 comms are OK and the buzzing may only be when slot2 stuff is being received. Very strange behaviour which is making me wonder again if it’s a bug in this firmware version.

No, don't mean the short burst of static at the start of a DMR transmission, the DMR decoding can be choppy and daleky.

Compared to P25 decoding on my AR-DV10, DMR is high-end audio though.
P25 on my AR-DV10 is just awful.

 

[G8OEO]

@palmerjrusa thanks for the replies.
So far I've only heard DMR stuff plus a quick burst of a clear Tetra channel.
The DMR quality is great IMO, provided I stick only to slot 1 .

 

[palmerjrusa]

@palmerjrusa thanks for the replies.
So far I've only heard DMR stuff plus a quick burst of a clear Tetra channel.
The DMR quality is great IMO, provided I stick only to slot 1 .

The issue I have with DMR signals with my AR-DV10 is the following.

If the DMR digital setting is "auto/color code off" I get the short data burst then it decodes fine, same for digital reception = DMR/color code squelch off with no short data burst now present.

As soon as I turn on the color code squelch in either of the above it decodes with audio dropouts every second or so.

Also, the DMR implementation in this receiver is rudimentary, there's no way to associate a frequency with a particular slot in the memory to confine reception of signals of the same frequency with one particular slot. At least none that I can determine.

 

[G8OEO]

Sorry to hear the DV-10 is giving you stress. I didn’t mess with colour codes so don’t know if the DV1 would behave in the same way. At least it does allow you to set pretty much any parameter independently for each memory channel which is good.

Unfortunately the problems I’m having with DMR reception on slot 2 are a deal breaker for me, so the DV1 is being returned. It’s really disappointing that AOR can produce such impressive tech and fail to get some of the important stuff quite right.

 

[palmerjrusa]

Sorry to hear the DV-10 is giving you stress. I didn’t mess with colour codes so don’t know if the DV1 would behave in the same way. At least it does allow you to set pretty much any parameter independently for each memory channel which is good.

Unfortunately the problems I’m having with DMR reception on slot 2 are a deal breaker for me, so the DV1 is being returned. It’s really disappointing that AOR can produce such impressive tech and fail to get some of the important stuff quite right.

Is that AR-DV1 blocked or you receive the unblocked version?

See you're in Northumberland, born and raised a little north and over the border.

 

[G7HID]

The issue I have with DMR signals with my AR-DV10 is the following.

If the DMR digital setting is "auto/color code off" I get the short data burst then it decodes fine, same for digital reception = DMR/color code squelch off with no short data burst now present.

As soon as I turn on the color code squelch in either of the above it decodes with audio dropouts every second or so.

Also, the DMR implementation in this receiver is rudimentary, there's no way to associate a frequency with a particular slot in the memory to confine reception of signals of the same frequency with one particular slot. At least none that I can determine.

Not making excuses for AOR but all their DMR testing is done with a radio communications test set, the reason being they have very little DMR in Tokyo and little they can air test with.. and in the past have relied on myself and others reporting and testing firmware fixes for DMR problems.... Tetra on the other hand they have stacks of..

Mike

 

[G8OEO]

Is that AR-DV1 blocked or you receive the unblocked version?

See you're in Northumberland, born and raised a little north and over the border.

Pretty sure it was an unblocked unit as normally sold in U.K.

I’m located in Ponteland not far from Newcastle Airport. Not a bad spot for DMR testing.

 

[G8OEO]

Not making excuses for AOR but all their DMR testing is done with a radio communications test set, the reason being they have very little DMR in Tokyo and little they can air test with.. and in the past have relied on myself and others reporting and testing firmware fixes for DMR problems.... Tetra on the other hand they have stacks of..

Mike

I wonder if my slot 2 DMR woes are entirely software related or maybe a function of dodgy hardware In that particular DV1.

I can only make a wild guess here but there might be some sort of decoder timing error/lag at the start of a slot 2 transmission which causes a little data from the tail end of Slot 1 to pollute the stream until the receive loop becomes properly locked on after a second or two.

I would love to know if other units have the same problem.

 

[G7HID]

Does this happen on all the DMR systems that you have listened to ?

Mike

 

[G8OEO]

It was one system with four UHF channels, another system with one channel.
Plus two different ones at VHF.
All the commercial repeater channels I could receive over the last few days produced the same problem fairly consistently and only ever on slot 2. Audio quality on slot 1 was pretty good in all cases.
I just got my DMR hotspot working this afternoon and it would have been good to experiment with that but too late now.

 

[G7HID]

OK...

Mike

 

[palmerjrusa]

It was one system with four UHF channels, another system with one channel.
Plus two different ones at VHF.
All the commercial repeater channels I could receive over the last few days produced the same problem fairly consistently and only ever on slot 2. Audio quality on slot 1 was pretty good in all cases.
I just got my DMR hotspot working this afternoon and it would have been good to experiment with that but too late now.

I'll check this out with my AR-DV1 and report back.

 

[G8PTN]

Hi All, I have not done extensive testing on DMR slots, I have the default setting of (1+2). I have been listening to my local repeater GB7NR on slot 2 this afternoon and have not noticed any issues.

The AR-DV1 is running firmware 1907B.

I wonder if it could be a timing issue, since DMR is generally quite sensitive to this.

73, Dave

 

[citiot]

Mine has always done this. Also, in auto, there is an occasional random "hiccupburpphartsniff" that seems to be the decoder trying to decode random static. Dunno.

 

[SigIntel8600]

My DV-1 was hanging on a frequency after scanning for a few minutes. I patiently loaded and tested every firmware from 1907B - 2205A. Same issues. My order of banks by mode was 1-P25, 2-FM, 3 TETRA, 4-AM. I found that the DV-1 was hanging on an AM bank of memories (specifically 121.5 AM) which followed an 800 MHz TETRA bank. I swapped banks - AM first then TETRA as the last bank, and no more hanging on AM. I run 1907B so I can run the eSPYonARD software.

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