Baud rate for p25 Bedford Police Dept.

[hellcat]

Does anyone know the P25 baud rate for the Bedford NH Police Dept? Is it 3600 or 9600?

I have an old Uniden BC250D that a family member gave me. Apparently I need a BCI25D card (to listen to the PD dispatch) that inserts into the scanner. However, no sense seeing if I can find one if the baud rate is not going to work as the 25d card only supports 3600.

It seems to be a very nice scanner other than that.

Check the link below as this is where I got my info.

Digital Scanner News, Rumors and Links Page...

Thanks all.

[AlabamaRS]

all true P25 will be 9600. true meaning No analog on the system

[hellcat]

Originally Posted by AlabamaRS

all true P25 will be 9600. true meaning No analog on the system

Thanks for your response.

However, I am confused. What is all true?

Some local PD's(in my area) upgraded to the P25 a few years ago. Given this, some are using the 3600 baud rate while calling themselves P25. Given this, I still need to confrim what they are using prior to buying something I do not need. I am hoping with a BCi25D my BC250D will accomplish the listening objective.

Does anyone know their baud rate? Or better yet can anyone suggest a reference to use? I have the latest Bearcat freq. book but all it lists is P25. I need a further break down of baud rate.

Thanks again.

[N_Jay]

From the database it looks like it is not trunked so the whole discussion of 3600 BPS vs. 9600 BPS (on the control channel) is irrelevant.

[hellcat]

Originally Posted by N_Jay

From the database it looks like it is not trunked so the whole discussion of 3600 BPS vs. 9600 BPS (on the control channel) is irrelevant.

Mmm...still confused---perhaps I am missing something?

My scanner is trunk capable. The issue is I cannot get the local PD any longer as they went to P25 a few years ago. I thought I needed a digital scanner supporting the P25 to receive their broadcast? The scanner I have will support the 3600BPS but it will not the 9600BPS. Given this, I thought I could obtain a BCi25D to upgrade the radio to P25 3600BPS. But if they are on the 9600BPS there is no point as my radio does not support the 9600BPS.

Is there any source one could reference to determine the BPS as all I can find is they (the PD), are P25.

Thanks to everyone who has responded thus far.

Tina S.

[ka3jjz]

N_Jay, the database isn't really up to date for this entry. The Scan New England wiki shows this freq to be a P25 conventional channel, so it's an interesting question 73 Mike

[edit] Here's the link to the Scan New England NH Portal - police for Hillsborough County - by the way, much as I hate to say it, this is a better site for freqs and such for the NE area...

http://www.scannewengland.net/wiki/i...ce_Departments

[N_Jay]

Originally Posted by ka3jjz

N_Jay, the database isn't really up to date for this entry. The Scan New England wiki shows this freq to be a P25 conventional channel, so it's an interesting question 73 Mike

[edit] Here's the link to the Scan New England NH Portal - police for Hillsborough County - by the way, much as I hate to say it, this is a better site for freqs and such for the NE area...

Hillsborough County Police Departments - Scan New England Wiki

Now you have confused me.

We both seem to agree that it is P25 CONVENTIONAL (not trunked) so how is it an interesting question? (not irrelevant?)

[ka3jjz]

Because I have a little P25 conventional by me, and I'd like to know the answer. 73 Mike

[UPMan]

Since conventional channels don't use a control channel, the answer to the question "Does the department use 3600 or 9600?" is "No."

To the OP: The BC250D with the BCi25D digital card can receive/decode P25 conventional. It can also receive/decode and track P25 channels on a Motorola system (those use 3600 bps control channels). It cannot be upgraded to receive/decode and track P25 trunked systems, which use a 9600 bps control channel (you can receive/decode the voice channels, but not track such systems).

[hellcat]

Originally Posted by UPMan

Since conventional channels don't use a control channel, the answer to the question "Does the department use 3600 or 9600?" is "No."

To the OP: The BC250D with the BCi25D digital card can receive/decode P25 conventional. It can also receive/decode and track P25 channels on a Motorola system (those use 3600 bps control channels). It cannot be upgraded to receive/decode and track P25 trunked systems, which use a 9600 bps control channel (you can receive/decode the voice channels, but not track such systems).

Finally I think I got it. Thank you UPMan!

So if I understand this, "If the PD is not trunked (which I do not think it is), then with the card upgrade I will be able to listen to their broadcast. Is this correct...what you call conventional?" "If the PD was trunked using the P25 (as we know it is), it would be considered the 9600 bps. I could still listen but not track. Is this correct?"

Very interesting debate none the same as I see others felt the same here based on the responses.

Thanks again.

[UPMan]

If the channels you want to monitor are conventional P25, then the card should take care of decoding the audio for you just fine.

Channels that are not on a trunked radio system are commonly referred to as "conventional" systems or channels.

If the PD was trunked, they could be on any number of system types, but if using P25 voice, that would narrow it down to two possibilities:

Motorola
P25 Standard

Motorola systems are capable of having both analog and digital voice channels. There are even a few Motorola systems that have only P25 voice channels (but they are still Motorola systems, as the control channel data is all in Motorola format, not the P25 trunking control protocol). The Nashua system is an example of a Motorola system that has some P25 voice channels (http://www.radioreference.com/apps/db/?sid=634).

P25 Standard trunked systems will always have only P25 voice channels. You'd need to head all the way to Greenwich CT for what appears to be the nearest P25 trunked system (http://www.radioreference.com/apps/db/?sid=6238).

[hellcat]

Originally Posted by UPMan

If the channels you want to monitor are conventional P25, then the card should take care of decoding the audio for you just fine.

Channels that are not on a trunked radio system are commonly referred to as "conventional" systems or channels.

If the PD was trunked, they could be on any number of system types, but if using P25 voice, that would narrow it down to two possibilities:

Motorola
P25 Standard

Motorola systems are capable of having both analog and digital voice channels. There are even a few Motorola systems that have only P25 voice channels (but they are still Motorola systems, as the control channel data is all in Motorola format, not the P25 trunking control protocol). The Nashua system is an example of a Motorola system that has some P25 voice channels (Nashua Trunking System, Nashua, New Hampshire - Scanner Frequencies).

P25 Standard trunked systems will always have only P25 voice channels. You'd need to head all the way to Greenwich CT for what appears to be the nearest P25 trunked system (Greenwich Public Safety System (Project 25) Trunking System, Fairfield, Connecticut - Scanner Frequencies).

Excellent info---very clear.

But of course a few other items come to mind now. So if a system is trunked p25 would that be considered the 9600 bps system? You said if "using P25 voice, that would narrow it down to two possibilities"

Motorola
P25 Standard

Is p25 standard and Motorola voice considered the 3600bps? Meaning dispatch is communicating via voice protocal?

What then is the focus on the P25 9600 BPS. Is that consider trunked p25---digitized voice?

Thank you in advance UPMAn.

[UPMan]

The 3600 vs 9600 is in reference to the bit rate of the control channel. It doesn't have anything to do with dispatch or any other voice comm. Check out the info on how trunking systems work here:
RadioSystemsOverview < UnidenMan4 < TWiki
http://www.uniden.com/products/ButIj...othePolice.pdf

[garys]

Originally Posted by hellcat

Excellent info---very clear.

But of course a few other items come to mind now. So if a system is trunked p25 would that be considered the 9600 bps system? You said if "using P25 voice, that would narrow it down to two possibilities"

Motorola
P25 Standard

Is p25 standard and Motorola voice considered the 3600bps? Meaning dispatch is communicating via voice protocal?

What then is the focus on the P25 9600 BPS. Is that consider trunked p25---digitized voice?

Thank you in advance UPMAn.

It can be confusing because often we mix terminology. "Motorola standard" trunking uses a 3600 bps data channel and can use either digital or analog voice. When people refer to those systems as "P25" they are really saying that it uses digital voice.

A true P25 trunking system, regardless of who makes it, uses a 9600 bps data channel and digital only voice, there is no analog voice use at all.

Conventional (non trunk) systems can use digital voice and sometimes people refer to this as P25 as well, even though no trunking is involved. Which is where Bedford comes into the picture. Bedford PC operates on VHF and uses digital (P25) voice.

To add to the confusion, P25 technology is open standard, but there are other proprietary digital voice systems available.

[hellcat]

Originally Posted by garys

It can be confusing because often we mix terminology. "Motorola standard" trunking uses a 3600 bps data channel and can use either digital or analog voice. When people refer to those systems as "P25" they are really saying that it uses digital voice.

A true P25 trunking system, regardless of who makes it, uses a 9600 bps data channel and digital only voice, there is no analog voice use at all.

Conventional (non trunk) systems can use digital voice and sometimes people refer to this as P25 as well, even though no trunking is involved. Which is where Bedford comes into the picture. Bedford PC operates on VHF and uses digital (P25) voice.

To add to the confusion, P25 technology is open standard, but there are other proprietary digital voice systems available.

Thank you Garys for your input. I think I got it now...man how confusing the P25 realm can be.

So given that Bedford uses VHF and uses P25 for it's voice I am confident I can use my BC250D Bearcat once I find a BCi25D card for it. Is my neophyte assumption correct?

Thanks all, I have learned a lot in a short time regarding P25.

Tina S.

[N_Jay]

It's really not that confusing.

As mentioned earlier, one of the biggest problem is that people take short-cuts with what they call different systems, and in the end it confuses everyone, especially those trying to learn by reading posts with short-hand names.

Systems can be Analog or Digital voice
Each digital system is different.
The most common is P25 and it is an open standard.
ASTRO and Pro-Voice are two examples of pre-P25 proprietary digital
ASTRO was Motorola, and Pro-Voice is Harris/Tyco/MA-COM

Systems can be conventional or trunked systems.
"Conventional" is the common name for non-trunked.
(Most) Trunked systems have a control channel that is unique for the type of trunking.
Conventional system do not have a control channel.
SmartNet-SmartZone, and EDACS are two very common but different proprietary trunking systems.
P25 Standards also contains a trunking control channel specification. (Different from SmartNet-SmartZone and EDACS

Some people use shorthand to name the protocols. SmartNet-SmartZone gets called 3600 baud (or BPS), and P25 gets called 9600 baud (or BPS),
EDACS is also usually 9600 BPS (But completely different than P25) but no one calls it 9600 PBS unless they are trying to differentiate it from a fairly rare type of EDACS that uses 4800 BPS. (Be happy for small favors)

Now, if that did not confuse you enough, Motorola built systems for a number of years using the SmartNet-SmartZone control channel and P25 voice channels. Hence the invention of systems mislabeled 3600 Baud P25.

If we would just clearly say what we really mean and get rid of the shorthand it would be so much easier.

As you have probably figured out, the system you are trying to listen to is a P25 conventional system.

As such it does not have a control channel, so the issue of control channel speed is irrelevant.
As for what scanner will receive it, any scanner capable of P25 will be fine.
Since it is not trunked you don't have to worry about whether your particular scanner is capable of P25 trunking or only the older Motorola and MA-COM signalling.

[garys]

Originally Posted by hellcat

Thank you Garys for your input. I think I got it now...man how confusing the P25 realm can be.

So given that Bedford uses VHF and uses P25 for it's voice I am confident I can use my BC250D Bearcat once I find a BCi25D card for it. Is my neophyte assumption correct?

Thanks all, I have learned a lot in a short time regarding P25.

Tina S.

Yes, exactly.

I was at You Do It Electronics in Needham a few weeks ago and I think they had a couple of these cards in a display case with other scanner and radio equipment. It might be worth a call to see if they actually have them or if it was just empty boxes.

[garys]

Yeah... the simplifies it quite a bit.

Originally Posted by N_Jay

It's really not that confusing.

As mentioned earlier, one of the biggest problem is that people take short-cuts with what they call different systems, and in the end it confuses everyone, especially those trying to learn by reading posts with short-hand names.

Systems can be Analog or Digital voice
Each digital system is different.
The most common is P25 and it is an open standard.
ASTRO and Pro-Voice are two examples of pre-P25 proprietary digital
ASTRO was Motorola, and Pro-Voice is Harris/Tyco/MA-COM

Systems can be conventional or trunked systems.
"Conventional" is the common name for non-trunked.
(Most) Trunked systems have a control channel that is unique for the type of trunking.
Conventional system do not have a control channel.
SmartNet-SmartZone, and EDACS are two very common but different proprietary trunking systems.
P25 Standards also contains a trunking control channel specification. (Different from SmartNet-SmartZone and EDACS

Some people use shorthand to name the protocols. SmartNet-SmartZone gets called 3600 baud (or BPS), and P25 gets called 9600 baud (or BPS),
EDACS is also usually 9600 BPS (But completely different than P25) but no one calls it 9600 PBS unless they are trying to differentiate it from a fairly rare type of EDACS that uses 4800 BPS. (Be happy for small favors)

Now, if that did not confuse you enough, Motorola built systems for a number of years using the SmartNet-SmartZone control channel and P25 voice channels. Hence the invention of systems mislabeled 3600 Baud P25.

If we would just clearly say what we really mean and get rid of the shorthand it would be so much easier.

As you have probably figured out, the system you are trying to listen to is a P25 conventional system.

As such it does not have a control channel, so the issue of control channel speed is irrelevant.
As for what scanner will receive it, any scanner capable of P25 will be fine.
Since it is not trunked you don't have to worry about whether your particular scanner is capable of P25 trunking or only the older Motorola and MA-COM signalling.

[hellcat]

Originally Posted by garys

Yes, exactly.

I was at You Do It Electronics in Needham a few weeks ago and I think they had a couple of these cards in a display case with other scanner and radio equipment. It might be worth a call to see if they actually have them or if it was just empty boxes.

Thanks Garys I will do that. Take care.

[hellcat]

Originally Posted by garys

Yeah... the simplifies it quite a bit.

Wow! If I just got that detail from the onset I would have not been confused. However, you did use confuse more than a few times in your detailed paragraphs (Ha, Ha, Ha).I agree as you have said: "If we would just clearly say what we really mean and get rid of the shorthand it would be so much easier." Bravo! If I had the granting power you should be awarded a Ph.D! Thanks for taking the time to break it down. My guess is others will refer to this thread as well.

Thanks again to all who helped.

Tina