Apco 25 Repeater?

[n4voxgill]

John, what prohibition is there that prevents ham radio manfufactuers from using anything that is not an open and the way describe it "free" modulation or any other thing including components? I know of none.

 

[kikito]

Point is that APCO Project-25 is not an "OPEN" standard and therefore not a permitted mode in the amateur radio service.

Well point us to an official document from the FCC, NTIA, APCO, PTIG, TIA, ARRL, etc. that states that, maybe we could all learn something rather than keep going back and forth like kids just repeating: is not, it is, is not, it is.... :roll:

 

[kg4icg]

P25 is an open standard and is allowed for use by ham radio, if you look at the ARRL website you just might find out a few things about it. As long as it is not encrypted in the eyes' and ears' of the FCC it is acceptable to be used by hams. By the way there are other digital voice modes out that hams use to that are being Produced by Icom, Alinco, and AOR.

R Collins 8)

 

[groftcc]

Alinco has a digital standard that they provide on some of their Ham radios. If I want to use this technology I have to buy it from Alinco. If you want to hear me while I use it you have to buy a radio from Alinco. This is no different then ASTRO/P25, ProVoice, ect. It's time for ham radio to evolve a bit. The old argument "it's encryption, it's a closed standard" is getting a bit old. P25 is a digital standard open for anybody who wants to use it. Just because you might not want to buy a digital radio doesnt mean that I should not be able to use the standard if I want to.

Craig

 

[n4voxgill]

reviewing some of the technical information on digital on the ARRL site shows that digital must remain within the emission limits for the band and the information about the mode used must be available. Hear is one article;

http://www.arrl.org/tis/info/pdf/0201028.pdf

I did not see any limitations other than don't waste bandwith and information be available. NO requirement for the equipment to be an open form, and not protected by patents.

If anyone can point out requirements it would be good to list them.

 

[nd5y]

Here are all the Part 97 rules on ham radio emission types.

http://a257.g.akamaitech.net/7/257/...ccess.gpo.gov/cfr_2004/octqtr/47cfr97.305.htm
http://a257.g.akamaitech.net/7/257/...ccess.gpo.gov/cfr_2004/octqtr/47cfr97.309.htm
http://a257.g.akamaitech.net/7/257/...ccess.gpo.gov/cfr_2004/octqtr/47cfr97.309.htm
http://a257.g.akamaitech.net/7/257/...ccess.gpo.gov/cfr_2004/octqtr/47cfr97.311.htm

 

[SCPD]

Point is that APCO Project-25 is not an "OPEN" standard and therefore not a permitted mode in the amateur radio service.

Hi John!

I remember you from the old HoustonScan days. That was a great resource to have.

P25 is about as open a standard as you can get. You can purchase copies of the copyrighted specifications here:

http://www.tiaonline.org/standards/search.cfm?keyword=Project+25

The IMBE vocoder is owned by DVSI. In exchange for APCO incorporating IMBE into the standard, DVSI agreed to make IMBE available under "RAND" terms - that's "reasonable and non-discriminatory".

Note: this was done almost ten years ago - now we have much better vocoder options that require zero licensing ... but what's done is done.

Now ... back to putting up a repeater - which was the original point of this thread. As long as the repeater is just passing data straight through without converting the raw bit stream to-or-from audio, then the DVSI patents are not being used in any way (the mobiles and handsets are another matter).

So ... yes it is an open standard and no you do not need a license to build a P25 capable repeater. If you do need to convert the 9600 baud bit stream into audio, DVSI will be more than happy to sell you a chip to do the job.

Regards,
Rick

 

[HabboX]

I remember you from the old HoustonScan days. That was a great resource to have.

Wow, that was long ago.

BTW, in the State of Texas if a radio company considers their digital mode to be "proprietary", then in the eyes of the law it is illegal to decode and it's considered to be scrambled or encrypted. This may not apply to P-25, but kikito mentioned Pro-Voice and Open-Sky.

 

[N_Jay]

To thow another curve here....

Am I misunderstanding this? To be P25 compliant means the product conforms to the standards set for the type of modulation etc.....

The vocoder algorithm (eg: IMBE) developed by DVSI is just a way to encode and compress the voice using the open "P-25" modulation standards (C4FM etc...). Another DSP compression and encoding scheme could be used and if that were the case then the licensing issue involving DVSI obviously wouldn't apply. The royalties or licencing would apply to whoever developed that format.


:?

mancow

Yes you are.

The CAI (Minimum standards to be P25 compliant) is the Modulation9C4FM/CQPSK), the voice coding (IMBE) and the channel coding. You need to implement all three in compliance with the standards.

 

[N_Jay]

Point is that APCO Project-25 is not an "OPEN" standard and therefore not a permitted mode in the amateur radio service.

1. It is an open standard.

2. It is permitted.

Sorry, your repeating your incorrect conclusion does not change the facts.

 

[N_Jay]

I remember you from the old HoustonScan days. That was a great resource to have.

Wow, that was long ago.

BTW, in the State of Texas if a radio company considers their digital mode to be "proprietary", then in the eyes of the law it is illegal to decode and it's considered to be scrambled or encrypted. This may not apply to P-25, but kikito mentioned Pro-Voice and Open-Sky.

1. Amateur radio is under Federal laws not state laws.

2. From my understanding of patent law, an amateur could build his own implementation of the DVSI IMBE algorithm legally without royalties.

Payments would only be required if he were to sell it, or use it for personal gain.

 

[SCPD]

BTW, in the State of Texas if a radio company considers their digital mode to be "proprietary", then in the eyes of the law it is illegal to decode and it's considered to be scrambled or encrypted. This may not apply to P-25, but kikito mentioned Pro-Voice and Open-Sky.

I think kikito is more concerned about Alaska state laws. What you describe is not far off from federal law. I think the federal law refers to communications where the operating paramters are not readily available to the public. Which part of the Texas Penal Code is this?

http://www.capitol.state.tx.us/statutes/pe.toc.htm

Is this under Title 7 Chapter 33 or 34 (or somewhere else) ?

-rick

 

[SCPD]

2. From my understanding of patent law, an amateur could build his own implementation of the DVSI IMBE algorithm legally without royalties.

This aspect of "fair use" - for academic and educational purposes - has been eroding in the courts. It started in 1980 when it became legal for publicly funded institutions to retain ownership of their inventions. Some say this gave universities an unfair advantage over privately funded research because they were able to avoid paying royalties on other patents while profiting on their own patents.

http://www.cnn.com/2003/EDUCATION/04/29/patent.universities.ap/

Corporate interests have been pushing towards making the universities pay just like every other for-profit entity.

-rick

 

[N_Jay]

2. From my understanding of patent law, an amateur could build his own implementation of the DVSI IMBE algorithm legally without royalties.

This aspect of "fair use" - for academic and educational purposes - has been eroding in the courts. It started in 1980 when it became legal for publicly funded institutions to retain ownership of their inventions. Some say this gave universities an unfair advantage over privately funded research because they were able to avoid paying royalties on other patents while profiting on their own patents.

http://www.cnn.com/2003/EDUCATION/04/29/patent.universities.ap/

Corporate interests have been pushing towards making the universities pay just like every other for-profit entity.

-rick

The magic words is "Profiting". Amateurs are precluded from Profiting from their hobby!

 

[N_Jay]

BTW, in the State of Texas if a radio company considers their digital mode to be "proprietary", then in the eyes of the law it is illegal to decode and it's considered to be scrambled or encrypted. This may not apply to P-25, but kikito mentioned Pro-Voice and Open-Sky.

I think kikito is more concerned about Alaska state laws. What you describe is not far off from federal law. I think the federal law refers to communications where the operating paramters are not readily available to the public. Which part of the Texas Penal Code is this?

http://www.capitol.state.tx.us/statutes/pe.toc.htm

Is this under Title 7 Chapter 33 or 34 (or somewhere else) ?

-rick

But the opperating parameters ARE readily available simply by purchasing the TIA specifications.

 

[SCPD]

But the operating parameters ARE readily available simply by purchasing the TIA specifications.

Not for ProVoice and OpenSky ... which was the reason for my question. I think we've put the ham P25 repeater issue to rest.

Should someone take the time to dissect and reverse engineer how a proprietary, non-published protocol works ... and then publish their findings ... that would eliminate the "not readily available" constraint. I'm just wondering how the Texas law(s) are worded.

-rick

 

[SCPD]

The magic words is "Profiting". Amateurs are precluded from Profiting from their hobby!

Nor was Duke University when sued because their purely academic work made use of two existing patents developed by former staff. I hope it really is that simple but ... (google time) ... here's a WSJ article on the topic ...

http://www.uh.edu/ednews/2004/wsj/200410/20041012laserpatent.html

Duke figured it had a solid defense. It was following a time-honored "experimental use" exception whereby academics, in the name of research, could infringe on patents so long as they didn't sell the results in commercial markets.

This is the same fair use that prevents liability for anyone who likes to tinker - whether kitchen table engineer or research scientist. In the suit, the conditions of "profit" get a little blurred.

Imagine using a drill to build something which you then sell. The concenpts behind the drill are owned by an employee. You (or your company) paid for parts to constuct the drill (or in the actual suit, a laser). The drill isn't incorporated into the end product and need never leave the shop floor. According to the suit described above, your company may be liable.

Clear as mud to me but that's law.

-rick

 

[N_Jay]

The magic words is "Profiting". Amateurs are precluded from Profiting from their hobby!

Nor was Duke University when sued because their purely academic work made use of two existing patents developed by former staff. I hope it really is that simple but ... (google time) ... here's a WSJ article on the topic ...

http://www.uh.edu/ednews/2004/wsj/200410/20041012laserpatent.html

Interesting.

And now you know why it is so important that amateur radio stay far away from commercial activities.

The whole hobby is about "Idle Curiosity"!

 

[HabboX]

Which part of the Texas Penal Code is this?

http://www.capitol.state.tx.us/statutes/pe.toc.htm

Is this under Title 7 Chapter 33 or 34 (or somewhere else) ?

I don't know. I'd have to go back and read it again. The laws in Texas regarding radio interception are almost word for word the same as Federal law, but where federal law says, "exception", the state law says, "Affirmative defense to prosecution."

I hired an attorney in July 2001 after I recorded the communications of a SWAT incident in which a SWAT team broke into the house of a man distraught over losing his business and having marital problems. A SWAT sniper shot another officer in the head, then the man inside was arrested an charged with Capital Murder.

Basically the attorney said that as long as the mode wasn't proprietary and the equipment to intercept the signals was readily available, then I could do whatever I wanted.

I can even disclose what I hear over the radio to a third party. Evidently there is plenty of case law that indicates that such disclosure is a right afforded under the first ammendment. I hired the same attorney to clarify that when I started AlertPages.com.

 

[rfaricy]

Point is that APCO Project-25 is not an "OPEN" standard and therefore not a permitted mode in the amateur radio service.

Absolutely wrong.

Alinco's digital modulation radios and card upgrades CERTAINLY don't use an open standard, but they still sell it, it is licensed, and is FCC type accepted. P25 is in fact an open standard and is permitted for use in amateur radios, as long as the transmissions are not encrypted. There are SEVERAL amateur repeaters in use which support P25, and some are P25 exclusively.

Any modulation, in fact, even experimental, can be used by amateurs so long as the transmissions are not encrypted.

Further, federal FCC laws supercede any of your Texas state laws (or in any state for that matter). Since the FCC allows for digital modulation by amateurs, any ham, anywhere in the US, may use it. If Texas bans the use of it, then they are referring to FCC licensees which do not hold amateur radio licenses (such as private businesses, etc), and cannot override the federal laws which permit amateurs to use digital modulation.

N0NRF
General Class Amateur Radio Operator
(And someone who knows what he is talking about)