DStar, and DMR radio are two different modes.
73 N2DYN Angelo
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Barry
Sent: Friday, March 06, 2015 4:02 PM
To: [log in to unmask]
Subject: Fwd: DMR radio
Sent from my iPhone
Begin forwarded message:
> From: Barry <[log in to unmask]>
> Date: 7 March 2015 4:58:23 am AWST
> To: "[log in to unmask]" <[log in to unmask]>
> Subject: Re: DMR radio
>=20
> Greetings.=20
> I'm totally blind and have been enjoying d-star for 12 months. I'm
>also us=
ing fusion. Haven't yet tried some yet=20
> Cheers.=20
> Barry VK6SP.=20
>=20
>=20
> Sent from my iPhone
>=20
>> On 7 Mar 2015, at 1:30 am, Maurice Mines <[log in to unmask]>
>> wrote:=
>>=20
>> Good morning everybody, as far as I know dstar, this the Jesu method
>>of =3D=
>> digitizing FM UHF VHF radio transmissions are both inaccessible to
>> the =3D=
>> blind.at this time.
>> So as far as I know nine people be able to make any use of the
>> digital =3D=
>> FM radio transmissions hardware and software it completely out of the
>> =3D=
>> question at this time. Can someone correct me if I=3DE2=3D80=3D99m
>> wrong?=
=3D
>> Hopefully one day someone will come up with a method to make this =3D
>> possible. The other issue that many of us have to think about is that
>> =3D=
>> the solution found it will be very costly. Considering that the last
>>=3D time I priced dstar equipment, the price was extremely
>>prohibitive. =3D That=3DE2=3D80=3D99s just my two cents worth for this
discussion.
>>=20
>> Sincerely Maurice mines.
>> message number, 505-369-3283. Note that the text that I have written
>>has =3D=
>> been dictated by using Dragon 4.0 for the Mac, some words, spellings,
>> =3D=
>> and/or syntax errors, may be the result provided the software or the
>> =3D dictation process.
>> Amateur radio call sign, kd0iko.
>> 73 to all and have a good weekend chasing the exit
>> that=3DE2=3D80=3D99s w=
hat =3D
>> you=3DE2=3D80=3D99re interested in doing.
>>> On Mar 4, 2015, at 8:21 AM, Bob Tinney <[log in to unmask]> wrote:
>>> =3D20
>>> Hi,
>>> =3D20
>>> Our local repeater club just ordered the new Yaesu System Fusion
>>> DR1-X=3D=
20=3D
>>=20
>>> repeater. The mobile Yaesu rig that will do C4FM digital is
>>> the=3D20 FTM400DR and a voice board is available for that model. It
>>> will=3D20 announce your call when you turn it on and will also tell
>>> you the=3D20 frequency your tuned to, but it will not tell you much
>>> else. C4FM=3D20 sounds much better than DStar. I don't know how it
>>> compares to DMR, =3D=
>> but=3D20
>>> anything is better than DStar.
>>> =3D20
>>> Bob, K8LR, [log in to unmask]
>>> =3D20
>>>> On 3/4/2015 8:57 AM, Martin G. McCormick wrote:
>>>> Our club had a really good presentation in February by a couple
>>>> of members about DMR which is also known in the US as MotoTRBO
>>>> pronounced MotoTurbo. I strongly suspect it is the new and neat
>>>> thing in amateur radio but it has a lot of growing up to do yet.
>>>> =3D20
>>>> Look it up in a Google search and there is a lot of information.
>>>> =3D20
>>>> DMR is an open-source standard which means anybody can make the
>>>> gear unlike DSTAR so we will probably eventually see many models.
>>>> =3D20
>>>> Here's the good and the bad.
>>>> =3D20
>>>> The best hand-held right now is sold by a company in the United
>>>> States called Connect Systems. I don't know if that's one or two
>>>> words. The radios are made in China but to commercial
>>>> specifications and sell for around $300 a piece to business and
>>>> public safety agencies. Connect Systems gives hams a really good
>>>> price break. The guys who gave the presentation say the radios are
>>>> good and solid like a Motorola. They are UHF only and will do
>>>> analog FM as well as DMR. I'd love to have one, myself, but read on
>>>> 'cause here comes the bad news.
>>>> =3D20
>>>> It's your typical screen toy. There are no voice prompts, no
>>>> helpful beeps except for one that tells you if you are trying to
>>>> transmit on an occupied channel, absolutely nothing that makes the
>>>> radio accessible. There's just a nice strip of glass across the
>>>> front.
>>>> =3D20
>>>> The programming software is all Windows, all the time, your
>>>> typical bundle of lost opportunity.
>>>> =3D20
>>>> Briefly, here is how DMR works.
>>>> =3D20
>>>> There are two tears of DMR. One is for simplex-type operation
>>>> such as what one might encounter in a business of some kind where
>>>> the staff carry talkies around for tactical communication. The
>>>> other tear is repeater-type operation.
>>>> =3D20
>>>> A repeater can handle two simultaneous QSO's and each
>>>> conversation can have a talk group. Think of the old community
>>>> repeater systems that used to be common in the commercial world.
>>>> Instead of different CTCSS tones, you have different talk group
>>>> numbers which is why the loud tone if somebody just transmits,
>>>> thinking the repeater is free when there is a conversation on their
>>>> time slot that is on a different talk group.
>>>> =3D20
>>>> Local systems are connected to the internet, kind of like
>>>> echolink but when you get a talk group going, you tie up one time
>>>> slot out of the two available and nobody else can use the system
>>>> for that slot unless they want to join the talk group.
>>>> =3D20
>>>> A UHF DMR repeater has one input frequency and one output just
>>>> like an analog repeater but two users can share the input because
>>>> their transceivers send packets of audio in bursts at about 20
>>>> bursts per second but the repeater tells each transceiver when it's
>>>> turn comes so they both interleave their packets. It's elegant but
>>>> I can't imagine it on ten or six meters due to the time lag over
>>>> skip distances. It would foul up the repeater's timing and you'd
>>>> probably be able to hear the distant signal but your signals would
>>>> take too long to get back to the repeater which would stray in to
>>>> the other guy's slot.
>>>> =3D20
>>>> I saw a lot of neat technology, here, but since there is no Linux
>>>> support, it's the same old same old.
>>>> =3D20
>>>> =3D09
>>>> Since DMR is an open standard, however, there is more likely to be
>>>> something useful later as more people will be making equipment.
>>>> =3D20
>>>> Sorry for the length of this post, but I figured some might find
>>>> it interesting.
>>>> =3D20
>>>> By the way, the audio is very good, similar to P25 if you have
>>>> heard that.
>>>> =3D20
>>>> 73
>>>> Martin WB5agz
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