I'm catching traffic on the system today and its Encrypted Comm's. Also, the system stopped tracking with 471.000/12.5 setup. Can anyone check it out to see if that setup it correct?
Franklin Twp. Trunk - BAD NEWS
- Thread starter nosoup4u
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I'll keep an eye on it as well. I thought I warned you guys months ago that the PD ops part would be encrypt....
Franklin is using the same communications consultant that Edison did, so I'd expect there to be a lot of similarities.
As for the county, Franklin considered jumping on that system but decided not to because:
poor coverage -- county was spec'ed out at something like 95% on street, Franklin wants 95% in-building.
analog -- county's sites are reportedly spaced too far for digital modulation, which bodes well for monitoring that system.
There were some other considerations too, both pro & con, but I don't remember them.
Jim Robbins
As for the county, Franklin considered jumping on that system but decided not to because:
poor coverage -- county was spec'ed out at something like 95% on street, Franklin wants 95% in-building.
analog -- county's sites are reportedly spaced too far for digital modulation, which bodes well for monitoring that system.
There were some other considerations too, both pro & con, but I don't remember them.
Jim Robbins
Sounds like they need to add a few more towers for better coverage!
73's
Ron
73's
Ron
That was the logistical issue I mentioned months ago - tower site problems. That's why Somerset County's system is running behind schedule for deployment.
From what I've heard from my sources, just about every municipal-level trunk system will be going with encryption for their police operations. Personally, Franklin PD talks way too much now as it is on their conventional channels - I'll be happy with just Fire & EMS.
I really don't miss it either with Edison. I was a member of Squad #1 for almost 2 years, and their Communications Officer. You get a little tired of hearing traffic stops & false burglar alarms. Although, the stuff they would be caught saying at 2 AM was quite entertaining!
From what I've heard from my sources, just about every municipal-level trunk system will be going with encryption for their police operations. Personally, Franklin PD talks way too much now as it is on their conventional channels - I'll be happy with just Fire & EMS.
I really don't miss it either with Edison. I was a member of Squad #1 for almost 2 years, and their Communications Officer. You get a little tired of hearing traffic stops & false burglar alarms. Although, the stuff they would be caught saying at 2 AM was quite entertaining!
You're right about that. I monitor Hillsborough PD all the time, but Franklin and some of the surrounding towns I don't start monitoring until after 10pm. Early in the morning (between 6-9am) can be interesting too. You either get the people who have been up allnight partying, or the people who went to bed mad and woke up even more p*ssed off.
rickey456
Member
Franklin Twp
My system has been apart since our last vacation. When I saw these posts I decided to set it up again and monitor Franklin Twp to check my calculations. Right now I'm receiving a 99.6% signal with the following Trunker readout:
c v 471.8250 1be 42 5a1
v 471.9750 1ca 4e 483
av 472.3250 1e6 6a 394
dv 472.3500 1e8 6c 442
av 472.9000 214 98 376
d 477.4000 278 ffff 0
I checked the math again and still get the 12.5 spacing. Let me know what you get. I have not tried to scan the system using a BC245.
I also received the following message from Trunker:
cell #1 using/may use f=0x1da
can someone tell me what that means? Is it because this is cell #2? BTW 1d8=472. Does that mean that a possible control channel for Cell#1 is 472.1500? Nothing heard here on that frequency.
No other activity seen in the last 2 hours.
My system has been apart since our last vacation. When I saw these posts I decided to set it up again and monitor Franklin Twp to check my calculations. Right now I'm receiving a 99.6% signal with the following Trunker readout:
c v 471.8250 1be 42 5a1
v 471.9750 1ca 4e 483
av 472.3250 1e6 6a 394
dv 472.3500 1e8 6c 442
av 472.9000 214 98 376
d 477.4000 278 ffff 0
I checked the math again and still get the 12.5 spacing. Let me know what you get. I have not tried to scan the system using a BC245.
I also received the following message from Trunker:
cell #1 using/may use f=0x1da
can someone tell me what that means? Is it because this is cell #2? BTW 1d8=472. Does that mean that a possible control channel for Cell#1 is 472.1500? Nothing heard here on that frequency.
No other activity seen in the last 2 hours.
RocketNJ
Member
Doing the math and comparing to Morris County's base/offset, it looks like Franklin/Somerset is the same as Morris.
You need two sets of base/offset entered.
Try the following:
Base 1 - 471.000 Offset 1 - 380 Spacing 12.5 kHz
Base 2 - 476.000 Offset 2 - 520 Spacing 12.5 kHz
This should provide proper tracking of the system.
George
You need two sets of base/offset entered.
Try the following:
Base 1 - 471.000 Offset 1 - 380 Spacing 12.5 kHz
Base 2 - 476.000 Offset 2 - 520 Spacing 12.5 kHz
This should provide proper tracking of the system.
George
rickey456
Member
There were two additional messages this morning:
cell #1 using/may use f=0x2bb
cell #1 using/may use f=0x1bb
cell #1 using/may use f=0x2bb
cell #1 using/may use f=0x1bb
I think that 2nd config did it. Now its tracking with the 12.5 step!
RocketNJ
Member
Glad to hearyou got it working.
Now we need someone to get trunker data for Burlington sowe can figure out that one. That too is probably split.
Now we need someone to get trunker data for Burlington sowe can figure out that one. That too is probably split.
nosoup4u said:
rickey456
Member
Rocket
I'm not familiar with the calculations that are neded for the digital radios. Can you show me how to do them to come up with that second set of values. Thanks.
I'm not familiar with the calculations that are neded for the digital radios. Can you show me how to do them to come up with that second set of values. Thanks.
RocketNJ
Member
Here's the original Trunker info for Franklin you posted.
c v 471.8250 1be 42 5a1
v 471.9750 1ca 4e 483
av 472.3250 1e6 6a 394
dv 472.3500 1e8 6c 442
av 472.9000 214 98 376
d 477.4000 278 ffff 0
System receive base range goes from 0 to 379 and system transmit from 380 to 760 (that is the scanners receive range). These are channel numbers associated with particular frequencies.
471.825 above has a hex channel number of 1be, or 446 decimal. 446 - 380 = 66 decimal. Now you need to assume a channel spacing (to be verified later). Let's assume 12.5 kHz (which is the correct step size for UHF T band systems). 66 x 0.0125 MHz = 875 kHz. So 471.875 MHz - 0.875 MHz + base freq of 471.000 MHz for the first range.
To prove that take another channel in the 471/472 range and do the math. Channel 2 is 472.325 MHz and hex chan number 1e6, decimal chan 486. 486 - 380 = 106. 106 x 0.0125MHz = 1.325 MHz. 472.325 - 1.325 MHz = 471.000 MHz. So we now know the first base, offset, and step are indeed 471.000/380/12.5 kHz.
Now for the second set. Since the other frequency you have listed is 477.400 with hex chan 278, decimal is 632. Doing the math you can see it wouldn't work out with the 471.000/380/12.5 kHz range. It is common for UHF T band and 500 MHz systems to have two sets of base/offset/step. Knowing that Morris County is set for 476.000/520/12.5 kHz for the second range I tested that using the 477.400 freq.
So 632 - 520 = 112. 112 x 0.0125 MHz = 1.4 MHz. 477.400 - 1.400 MHz = 476.000.
If you did not know the second base/offset/step then you would need to know at least two frequencies in the second freq range (476 - 478) in order to calculate it out.
Now with that said if anyone can get the Trunker data for Burlington we can figure out the tables.
c v 471.8250 1be 42 5a1
v 471.9750 1ca 4e 483
av 472.3250 1e6 6a 394
dv 472.3500 1e8 6c 442
av 472.9000 214 98 376
d 477.4000 278 ffff 0
System receive base range goes from 0 to 379 and system transmit from 380 to 760 (that is the scanners receive range). These are channel numbers associated with particular frequencies.
471.825 above has a hex channel number of 1be, or 446 decimal. 446 - 380 = 66 decimal. Now you need to assume a channel spacing (to be verified later). Let's assume 12.5 kHz (which is the correct step size for UHF T band systems). 66 x 0.0125 MHz = 875 kHz. So 471.875 MHz - 0.875 MHz + base freq of 471.000 MHz for the first range.
To prove that take another channel in the 471/472 range and do the math. Channel 2 is 472.325 MHz and hex chan number 1e6, decimal chan 486. 486 - 380 = 106. 106 x 0.0125MHz = 1.325 MHz. 472.325 - 1.325 MHz = 471.000 MHz. So we now know the first base, offset, and step are indeed 471.000/380/12.5 kHz.
Now for the second set. Since the other frequency you have listed is 477.400 with hex chan 278, decimal is 632. Doing the math you can see it wouldn't work out with the 471.000/380/12.5 kHz range. It is common for UHF T band and 500 MHz systems to have two sets of base/offset/step. Knowing that Morris County is set for 476.000/520/12.5 kHz for the second range I tested that using the 477.400 freq.
So 632 - 520 = 112. 112 x 0.0125 MHz = 1.4 MHz. 477.400 - 1.400 MHz = 476.000.
If you did not know the second base/offset/step then you would need to know at least two frequencies in the second freq range (476 - 478) in order to calculate it out.
Now with that said if anyone can get the Trunker data for Burlington we can figure out the tables.
RocketNJ
Member
Oh, and these calculations are valid for any Motorola Trunked system whether analog/digital, VHF/UHF/800, etc.
rickey456
Member
Rocket
Thanks for the explanation. Not having a digital radio, I didn't understand what was needed. So let's look at Edison Twp.
There is a 6th frequency [which never made sense to me because I couldn't work it into the '380' formula]---
478.7125 339 ffff 0
--------------
there's the key-- the ffff,0
339h= 824 dec
824 - 520 = 304 x 0.0125 = 3.8
478.7125 - 3.8000 = 474.9125 with 12.5 spacing
So guys here's the second freq, for Edison.
As far as Burlington County- do anyone know if the system can easily be picked up in Philadelphia? If so, the next time I visit my daughter in Center City I will get a Trunker reading on it.
Thanks for the explanation. Not having a digital radio, I didn't understand what was needed. So let's look at Edison Twp.
There is a 6th frequency [which never made sense to me because I couldn't work it into the '380' formula]---
478.7125 339 ffff 0
--------------
there's the key-- the ffff,0
339h= 824 dec
824 - 520 = 304 x 0.0125 = 3.8
478.7125 - 3.8000 = 474.9125 with 12.5 spacing
So guys here's the second freq, for Edison.
As far as Burlington County- do anyone know if the system can easily be picked up in Philadelphia? If so, the next time I visit my daughter in Center City I will get a Trunker reading on it.
rickey456
Member
Rocket NJ
Is that second number always 520?
Is that second number always 520?
RocketNJ
Member
The base/offset/step can be anything.
Think of it as a reference table.
The TRS database says that the base is 470.000 MHz, offset 380, and 12.5 kHz spacing. Without the second entry in the table the highest mappable channel would be 474.450 MHz. There are 380 "channels" available in the table). 380 x 0.0125 MHz = 4.450 MHz. 470.000 + 4.450 = 474.450 MHz.
Since some systems have frequencies that fall out of the range with just one base/offset/step entry, they need a second entry.
Since we know that the frequency in question is 478.7125 MHz and it's channel ID is 339H or 825 Dec (you were off by 1), let's assume step is 12.5 kHz since the channel is not divisible by 25 kHz, and the base for the second group is 476.000 MHz (the beginning of the second range of infrastructure tx range in T Band (the 470 T band tx goes from 470.000 to 472.9875 and 476.000 to 478.9875). So with assuming base of 476.000 and step of 12.5 kHz you can calculate out an offset of 608.
Notice we cannot use 520 as in Franklin or Morris? 472.450 MHz which is one of Edison's channels is channel 576 Dec, or 240 Hex. Check my math with Trunker. Since 576 Dec is higher than 520 you can see the system cannot use 520 as the second offset.
It is up to the system engineer to set the tables up based upon frequencies used in the system.
The key is the second offset cannot be lower than the channel number of the highest freq in the lower frequency range. In your example of using 520 for the second offset the scanner would not receive 472.450 MHz freq since it would not map out to a channel.
It is confusing but I hope this sheds some more light on the subject.
Try the first table entry as 470.000/380/12.5 and second entry as 476.000/608/12.5. Let me know the results.
Think of it as a reference table.
The TRS database says that the base is 470.000 MHz, offset 380, and 12.5 kHz spacing. Without the second entry in the table the highest mappable channel would be 474.450 MHz. There are 380 "channels" available in the table). 380 x 0.0125 MHz = 4.450 MHz. 470.000 + 4.450 = 474.450 MHz.
Since some systems have frequencies that fall out of the range with just one base/offset/step entry, they need a second entry.
Since we know that the frequency in question is 478.7125 MHz and it's channel ID is 339H or 825 Dec (you were off by 1), let's assume step is 12.5 kHz since the channel is not divisible by 25 kHz, and the base for the second group is 476.000 MHz (the beginning of the second range of infrastructure tx range in T Band (the 470 T band tx goes from 470.000 to 472.9875 and 476.000 to 478.9875). So with assuming base of 476.000 and step of 12.5 kHz you can calculate out an offset of 608.
Notice we cannot use 520 as in Franklin or Morris? 472.450 MHz which is one of Edison's channels is channel 576 Dec, or 240 Hex. Check my math with Trunker. Since 576 Dec is higher than 520 you can see the system cannot use 520 as the second offset.
It is up to the system engineer to set the tables up based upon frequencies used in the system.
The key is the second offset cannot be lower than the channel number of the highest freq in the lower frequency range. In your example of using 520 for the second offset the scanner would not receive 472.450 MHz freq since it would not map out to a channel.
It is confusing but I hope this sheds some more light on the subject.
Try the first table entry as 470.000/380/12.5 and second entry as 476.000/608/12.5. Let me know the results.
478.7125 was Edison's old EMS repeater. Notice how all of Edison's freq's are narrow-band 3-digit types (ie-472.450)? The 478.7125 wouldn't fit into the narrow-band requirements. Plus, they would have had to set up a multi-table layout just for one frequency...
Rickey,
There is no one on the Burlington County system yet at all. The fleetmaps and assignments haven't even been finalized, and the radios still have the default test channels stored in them.
There is no one on the Burlington County system yet at all. The fleetmaps and assignments haven't even been finalized, and the radios still have the default test channels stored in them.
I caught some radio tech's on the Franklin & Somerset system just a while ago. I still had the 2ndary config set to 520 and it was tracking the talkgroups fine. 1 tech was on the somerset system, talking to the other tech on the franklin system on t/g 1616 in analog mode. Later on, I was catching clear digital on 40016.
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