Pure DMR simplex doesn't require synchronisation as the timeslots are ignored. Dual Capacity Direct Mode and repeaters do, of course, require a timing sync signal from either a nominated timing leader or repeater. In both cases, lack of sync doesn't actually make things "fall apart", it's just impossible to gain access and you get the low beep of failure.
449 UK simple irritating noise?
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Re: 449 UK simple irritating noise?
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Re: 449 UK simple irritating noise?
Thanks for that! I wondered how it all worked, I knew there was something to with timing but not sure what as I'm still new to it myself.
Sent from my GP300 using DTMF
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Re: 449 UK simple irritating noise?
hi andy,(i think that you was the you that posted the original post) i have read all off the posts , and although i don't quite know what type of noise you are refering to , there is a company called lh agro which transmit data on lots of freqencies including 449.450 and they have something to do with farm machinery tractor data ect and can wipe out some of the 449 mhz chanells the other one is 453.550 , which is a common railtrack frequency. if you look on the ofcom website you will find out which other frequencies are affected . i have one of these transmitters about 10 miles from me and it some of the 449.mhz chanells are unuseable
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Re: 449 UK simple irritating noise?
I thought d m r was all suppose to be analogoue
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Re: 449 UK simple irritating noise?
Thanks for all the suggestions. It's DMR simplex by the sound of it. There seems to be more of it every day.
'SOMEONE GET ME A SAW!'
Andy.
Andy.
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Re: 449 UK simple irritating noise?
Sorry I meant I thought all 449 channels had to be analogoue
Sorry my wrong word Andy
Sorry my wrong word Andy
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Re: 449 UK simple irritating noise?
It seems more and more users are migrating to DMR so restricting the 449 and 458 MHz channels to analog only would just create a headache.
I believe as long as conforming to the license conditions then any mode of transmission is acceptable.
2M0SRM
Quansheng tg-uv2
yaesu FT-7900E
Motorola DP3600 UHF + VHF
MTH800
MTP850s
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Quansheng tg-uv2
yaesu FT-7900E
Motorola DP3600 UHF + VHF
MTH800
MTP850s
SRH3800
CM-9000
MTM5400
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Re: 449 UK simple irritating noise?
That’s annoying
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Re: 449 UK simple irritating noise?
The new Mitex DMR handies seem popular.
- Werthers
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Re: 449 UK simple irritating noise?
Time for DMR scanners. I haven't seen any DMR scanners about but I'm sure it wont be long now.
There are a couple handheld DMR radios that offer a scan function which scan color codes, time slots, and talk groups when a DMR signal is found.
There are a couple handheld DMR radios that offer a scan function which scan color codes, time slots, and talk groups when a DMR signal is found.
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Re: 449 UK simple irritating noise?
Looking above £300 for a DMR scanner but they are out there and work.
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Re: 449 UK simple irritating noise?
Is Whistler t r x 1 any good
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Re: 449 UK simple irritating noise?
using a baofeng dm1801 with the recently deceased opengd77 firmware, using it to listen into DMR. you can disable cc and tg filtering.
it can't scan ranges but i usually find frequencies via SDR.
it can't scan ranges but i usually find frequencies via SDR.
SDRPlay RSP1A + CrossCountryWireless Loop
Icom IC7410 + thunderpole boomerang
Retevis RT90 (opengd77) + Diamond x50
Yupiteru MVT-9000MKII, Baofeng DM-1801 (with opengd77)
Icom IC7410 + thunderpole boomerang
Retevis RT90 (opengd77) + Diamond x50
Yupiteru MVT-9000MKII, Baofeng DM-1801 (with opengd77)
- Werthers
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Re: 449 UK simple irritating noise?
Is Whistler any good