moto type 2 vs P25 phase 1

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vocoder

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Why does moto type 2 CC seem to have more of a "punch" than P25 phase 1 CC?
Is type 2 wider than P25? Baudrate? Protocol differences? (one protocol less influenced by noise than the other?)
I'm guessing the P25 is more narrow than the type 2.
 

troymail

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Why does moto type 2 CC seem to have more of a "punch" than P25 phase 1 CC?
Is type 2 wider than P25? Baudrate? Protocol differences? (one protocol less influenced by noise than the other?)
I'm guessing the P25 is more narrow than the type 2.
Punch... how do you mean?

P25 control channels are 9600 baud while older Motorola (aka? P16) are 3600 baud... The "slower" signal probably sounds like you can hear more shifts in the data stream while the P25, being much faster, provides less of that type of sound.

I believe they both use pretty close to if not the same bandwidth.
 

vocoder

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sorry, lack of a better word.
"punch" = louder, when listening too, moto type 2 CC seems to travel a bit more distance.
Audio of moto type 2 CC appears to be louder than P25 phase 1 CC, at the same scanner volume setting.
 

troymail

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sorry, lack of a better word.
"punch" = louder, when listening too, moto type 2 CC seems to travel a bit more distance.
Audio of P25 phase 1 appears to be lower than type 2 at the same scanner volume setting.
It is certainly true that the older signals - trunked or conventional - "travel" (can be received) further away....

Newer systems are generally required to provide coverage but not much beyond the intended area of coverage. In some cases, multi-site (aka "state" or other) systems even reuse their frequencies within their own systems. This isn't possible if the signal is so strong and travels as far -- it would only serve to interfere with that and other systems using the same frequencies.
 

vocoder

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Maybe it has something to do with Motorola type 2 being able to use analog VC's, thereby the CC protocol would have to different from the P25 phase 1 CC.
 

troymail

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Maybe it has something to do with Motorola type 2 being able to use analog VC's, thereby the CC protocol would have to different from the P25 phase 1 CC.
:confused:

The protocols/data streams are certainly different. However, the signal strength differences (which dictate the distance) are simply related to newer requirements and changes in technology.
 

marksmith

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Maybe it has something to do with Motorola type 2 being able to use analog VC's, thereby the CC protocol would have to different from the P25 phase 1 CC.
I think it's mainly due to lack of directional output (wider propogation), and as was mentioned, limited coverage outside jurisdiction of use.

P25 is part of the improved utilization of the spectrum, while the Motorola Type II technology is prior to the more recent legislation concerning rebanding and other spectrum efficiency.

It is still in the brute force FM days that supports wide band analog voice in addition to the first digital voice protocols.

536/436/ws1095/996p2/996xt/325p2/396xt/psr800/396t/HP-1/HP-2 & others
 

slicerwizard

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P25 control channels are 9600 baud while older Motorola (aka? P16) are 3600 baud... The "slower" signal probably sounds like you can hear more shifts in the data stream while the P25, being much faster, provides less of that type of sound.
P25 control channels are 4800 baud, which is only one third faster than 3600 baud Moto CCs.

The FM demodulated audio of a 3600 baud control channel sounds louder than that of a C4FM P25 control channel because it is louder.
 

troymail

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Ok - maybe this is where I was confused...

https://wiki.radioreference.com/index.php/APCO_Project_25


Motorola ASTRO IMBE

This is a P25 non-compliant Motorola digital solution, and is also called the "ASTRO Digital CAI (Common Air Interface) Option". This is a proprietary trunking solution that uses the Project-25 vocoder as its digital voice solution on top of a standard Motorola Type II Smartnet/Smartzone system.
  • The Motorola ASTRO IMBE solution uses the Motorola Type II 3600 Baud Smartzone control channel.
  • The Motorola ASTRO IMBE solution can allow both analog and P25 CAI digital radios to operate on the same network.
Project 25 Digital Trunking

This is the Project 25 Digital trunking solution that is vendor independent and designed around the Project 25 Digital Trunking standards. The State of Michigan, the State of Colorado and the State of Illinois (STARCOM21) are three systems that use this format.
  • Project 25 Trunking uses a 4800 baud, 9600bps control channel.
  • All radios on a Project-25 Digital trunking system must use digital voice - no analog trunking capability is provided.
 
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Ok - maybe this is where I was confused...

https://wiki.radioreference.com/index.php/APCO_Project_25


Motorola ASTRO IMBE

This is a P25 non-compliant Motorola digital solution, and is also called the "ASTRO Digital CAI (Common Air Interface) Option". This is a proprietary trunking solution that uses the Project-25 vocoder as its digital voice solution on top of a standard Motorola Type II Smartnet/Smartzone system.
  • The Motorola ASTRO IMBE solution uses the Motorola Type II 3600 Baud Smartzone control channel.
  • The Motorola ASTRO IMBE solution can allow both analog and P25 CAI digital radios to operate on the same network.
Project 25 Digital Trunking

This is the Project 25 Digital trunking solution that is vendor independent and designed around the Project 25 Digital Trunking standards. The State of Michigan, the State of Colorado and the State of Illinois (STARCOM21) are three systems that use this format.
  • Project 25 Trunking uses a 4800 baud, 9600bps control channel.
  • All radios on a Project-25 Digital trunking system must use digital voice - no analog trunking capability is provided.
Not entirely. The actual flash option on Motorola equipment is for "9600 baud trunking" (P25 trunking). The basic error, the term baud is often referred to represent the over the air data rate in bps where it really should refer to the symbol rate (two bits per symbol for C4FM). It's one of the overlooks in P25. 3600 baud is really 3600 bps control channel and 9600 baud is really 9600 bps.
 
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