New generation of MMDVM's ?

asgard

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What you think about a new generation of multimode Hotspots based on CML Micro baseband ic's like CMX998/CMX981 or sdr technology?

As MMDVM was a game changer in digital communication for hams and Jonathan Naylor have his well deserved place in history book for this shift, i really belive that actual mmdvm boards, simplex or duplex reached they full potential and despite of design improvements nothing new can come.
Beside DMR and P25 , (ignoring c4fm,dstar,pocsag, analog) TETRA is a huge desired feature for hotspots to be used world wide in ham hobby, really nice to have it in PiStar or simillar. (I remember that Andrew Taylor was open to this ideea) , feature not suported by actual hw /sw and a challange for some "smart people" .
Past 2 years i heard same stories as: " someone is working", "cannot be done" ,"no hw available" "so sw available" "if you want it so bad whay you don't doit youself" etc.
I'm still wonder if from so many smart fellow hams with strong knowledge in hw/sw we can't make a team for this project and even fund the team and product , something like kickstarter project so will be a win/win for everyone ?
 

wowologist

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Isnt TETRA encrypted by design...which makes it completely unusable for amateur radio use?
 

wowologist

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"There are Tetra SDR software apps that decode unencrypted transmissions. I'm not sure why it wouldn't work for amateur radio."

Um, because it's against the law to obfuscate communications while transmitting as an amateur radio operator...
 

R0am3r

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"There are Tetra SDR software apps that decode unencrypted transmissions. I'm not sure why it wouldn't work for amateur radio."

Um, because it's against the law to obfuscate communications while transmitting as an amateur radio operator...
Digital signals and encrypted signals are not the same thing. Digital signals (DMR, P25, NXDN, TETRA, and others) are certainly allowed on the amateur radio bands.
 

wowologist

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TETRA is not just digitally encoded it has an encryption algorithm inherent to itself(albeit extremely weak). That's why a specialized decoder had to be created for it, and the only reason like 10~ is years ago it really wasnt put into public service use in the US (as I recall) was because at the time BIG/M\oto had competing tech and didnt want "euro-trash" encroaching on ther US contracts...
 

asgard

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TETRA is not just digitally encoded it has an encryption algorithm inherent to itself(albeit extremely weak). That's why a specialized decoder had to be created for it, and the only reason like 10~ is years ago it really wasnt put into public service use in the US (as I recall) was because at the time BIG/M\oto had competing tech and didnt want "euro-trash" encroaching on ther US contracts...
No is not. you are wrong. Tetra is allowed in ham, there is tetra clear, no encryption. do a search after tetra algo, tea etc. debating if tetra is allowed /legal or not is not the point as we have the answer already .
br'
 

wowologist

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Ahh so your one of the ones that actually think D-star is legal for ham use also....neways...gg
 

Will001

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Maybe the "next generation" doesn't want to throw hundreds, possibly thousands, at HF equipment. Why are so many in the "old guard" of the HAM community so opposed to experimenting with new technology? And they wonder why young people are so disinterested with this hobby...

Ahh so your one of the ones that actually think D-star is legal for ham use also....neways...gg
Like asgard said, digital voice and ENCRYPTED digital voice are two totally different things. Unencrypted digital voice is totally legal whether it is P-25, DMR, DSTAR, TETRA, NXDN, or any other digital voice mode that can be transmitted and received in the clear. The moment someone slaps encryption on their signal, it becomes illegal. Maybe you are thinking of TETRAPOL, which has built-in encryption.
 

kb9mwr

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Maybe the "next generation" doesn't want to throw hundreds, possibly thousands, at HF equipment. Why are so many in the "old guard" of the HAM community so opposed to experimenting with new technology? And they wonder why young people are so disinterested with this hobby...


Like asgard said, digital voice and ENCRYPTED digital voice are two totally different things. Unencrypted digital voice is totally legal whether it is P-25, DMR, DSTAR, TETRA, NXDN, or any other digital voice mode that can be transmitted and received in the clear. The moment someone slaps encryption on their signal, it becomes illegal. Maybe you are thinking of TETRAPOL, which has built-in encryption.
Just ignore people like that. There were patent issues concerning the vocoder of D-Star, but those expired a few years back. And there has been a working voice decoder for a number of years. I bet that guy doesn't even support use open source, he just is using that past issue for arguing purposes. It gets old folks.
 

KD8DVR

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No is not. you are wrong. Tetra is allowed in ham, there is tetra clear, no encryption. do a search after tetra algo, tea etc. debating if tetra is allowed /legal or not is not the point as we have the answer already .
br'
But not in the USA... Tetra is illegal here, except for one system in NJ that has a waiver.
 

kb9mwr

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To clarify: Tetra isn't illegal in the USA because of encryption as that can be turned off. It's illegal because we have outdated rules, and the 4 slot TDMA that it uses isn't a permitted emission type here in the good old USA.
 

jparks29

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Ahh so your one of the ones that actually think D-star is legal for ham use also....neways...gg
You do realize that modern encryption is just another digital mode these days, right?

Use a public standard, like AES, and publish the key. You're no longer obfuscating your message, just operating on a different digital mode. Now, whether or not someone has the equipment is their problem. It'd be like someone complaining they can't listen to APRS packets because they don't have a TNC or tracker.
 

jparks29

John McClane
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as far as hotspots and whatnot goes... I think people are going backwards. The idea isn't to rely on the internet to carry your traffic, it's to use H/W that allows multiple simultaneous modes. No more buying super expensive proprietary hardware.

You have repeaters that cover half of state, hundreds if not thousands of square miles, able to be analog, or any flavor of digital, seamlessly.
 
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