Base, step & offset ch.

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2WAYMAN

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4-14-12 3 PM EDT
Hi all.........
Have been trying to get straight answers about determining the base channel step and offset channels for a Uniden BC296D and BC796D for the Bergen County, NJ Trunked system.
Recently started using UniTrunker (latest version) and have a couple of questions for you very experienced users.
I noticed and opened the Frequency Tab and see all of the working frequencies except for one which I had also programmed per the RR Database.
Then I opened the BandPlan tab and I see the listing for the 450,470,500,700 and 800 mhz bands. When I am running UniTrunker, I notice in the Activity screen the frequencies and to the left of same is the column called LCN (Logical Channel Number) which I thought was only used in Edacs systems. The Bergen County system is a UHF Motorola Type 2 Common Air Interface Exclusive system and what I am trying to obtain is the Base Frequency number(s) ("offset channel(s)") from Uni Trunker. Is that the same as the LCN listed? I have UniTrunker running in Decimal display mode. I am also using the Butel ARC250 Pro software to program these two scanners and in the Trunked Settings it is asking for the system type: Motorola Type II UHF and then for the following:
Frequency Step Offset Channel
Base Config 1 ? ? ?
Base Config 2 ? ? ?
Base Config 3 ? ? ?

I'm not sure whether the step is supposed to be 6.25 or 12.5 and what frequencies should I be using for the three entries. Also, how/where do I find the 'channel numbers' (offset ch.) in UniTrunker? In the article in the RR Wiki entitled : 'Determining Base/Offset and Step in Motorola UHF/VHF Trunked Radio Systems' , it states that in Trunker (the DOS version) the channel numbers were right after the frequency, displayed in hex, but they don't even seem to be showing up there in my 3.8.3 v of M-Trunker either?
Can anyone please shed some light on this and let me know what values to put into my ARC250 Table for this system??
Many thanks in advance for any/all asistance!
73's
 

SCPD

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I notice in the Activity screen the frequencies and to the left of same is the column called LCN (Logical Channel Number) which I thought was only used in Edacs systems.
You are correct. The term was borrowed from EDACS. Every trunking protocol supported by Unitrunker uses channel numbers. "LCN" was a convenient term familiar to all.

The Bergen County system is a UHF Motorola Type 2 Common Air Interface Exclusive system
That's not what I see in the database.

All systems in Bergen County ...

Bergen County, New Jersey (NJ) Scanner Frequencies and Radio Frequency Reference

The Bergen County system ...

Bergen County Trunking System, Hackensack, New Jersey - Scanner Frequencies

This is not a Type II Motorola system. The control channel is P25. The BC296D and BC796D understand P25 voice channels but not the control channel. P25 control channels broadcast the bandplan information over the control channel. On a scanner that supports P25 control channels, you only need the control channel frequencies. The radio acquires the bandplan directly from the control channel.
 

loumaag

Silent Key - Aug 2014
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....
The Bergen County system ...

Bergen County Trunking System, Hackensack, New Jersey - Scanner Frequencies

This is not a Type II Motorola system. The control channel is P25. The BC296D and BC796D understand P25 voice channels but not the control channel. P25 control channels broadcast the bandplan information over the control channel. On a scanner that supports P25 control channels, you only need the control channel frequencies. The radio acquires the bandplan directly from the control channel.
I assume the 296D is just like the 796D; depending on the firmware version (the most recent being necessary) it will handle VHF/UHF P25 just fine. I don't have a system here to re-verify, but it worked when I was in SD and took it to Rapid City for the AFB there. My Pro-96 was too painful to set up for the short time I was there, but the 796D worked just fine.
 

2WAYMAN

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Base,Step & Offset Channels for BC796D&BC296D

4-15-12 1609 hours edt
Hello Fellows and thanks Lou and Unitrunker for the replies-finally some concrete answers!!
Yes, both my Uniden BC296D (portable) and BC796D mobile) have the latest firmware upgrades.
Now, do I need to use the table with the Butel ARC250 software for the Bergen County Motorola Type II
UHF trunked system or not? If so, what do use for the entries in that table (which I have listed and described in my initial post). I have tried numerous combinations of data from others who have made suggestions but NONE of them work. Also, should I put all 7 frequencies (control and 3 alternate control and three voice) for the Alpine site in the software ??? The system is simulcast anyway.
If either or both of you can list what data should appear in that table for me I would greatly appreciate it as I have already spent too many hours trying to get these to work correctly.
My BCD396XT and the BCD996Ds in our unmarked cars work fine -they were a snap to program as they have a setting for P25 in the software/firmware for same and as you stated do read the CC stream for the bandplan info.
Thanks in advance once again and 73's!
 

loumaag

Silent Key - Aug 2014
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Okay, if I remember correctly, for P25 VHF/UHF, set the setting for VHF (or UHF) Moto II. Put anything in the table setup, it will be ignored when the radio detects a P25 signal on the CCh and then it will detect the channel lineup from the P25 CCh stream. As I said earlier, I only did this when I was in SD and I left there late in 2005. I have not done it since, so the memory card may be a little dusty. ;)
 

W2SJW

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Please stop referring to the system as a Motorola Type-II, it is not. It is a standard P25 9600 baud system. You are confusing yourself right from the start if you are looking at options for the system when you have the software set to 'Type-II' mode.

If you have successfully set up the 396 & 996's on that system, look at the band plan that the system fed into those units (through the screen, or the software) and that will give us a starting point as to how to help you figure out the tables that the old models need.
 

karldotcom

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Well, to be fare, the programming screen for the 796D says "4: TYPE2/P25 UHF" and it asks you for the settings.


Can you post a pic of your Unitrunker screen?

or type out a list of the LCN and what frequency corresponds to it?
 
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2WAYMAN

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Base, Offset Channel & Step

4-15-12 2125 hours edt
Hi guys and thanks for the help. I just ran UniTrunker using my 396XT for inline signal and these are the frequencies which showed up tonight: ( I had the display set for DECIMAL)
LCN: Freq..:
03-0434 472.71250 alt cc (listed in RR as the actual cc)
03-1150 477.18750 alt cc
03-1202 477.51250 cc tonight
04-1374 478.58750 alt cc
Now, per RR database, the same Alpine site also has the following frequencies listed:
472.63750 , 477.16250, 477.53750

The other site at MAHWAH hjas the following frequencies listed, but I cannot receive the cc at my location and I have been told the antenna is facing west and I am south of it.
470.8750, 471.1250, 472.2250, 472.3250 (supposed cc),472.9000 and 477.21250

Looking forward to finally being a ble to program these units! Thanks again for all the assistance! 73;s
 

karldotcom

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If you are using Butel to program the scanner, put all seven of those frequencies listed in the same bank (in a row, 1-7).....

Under Trunk -> System Settings, select "Motorola Type 2/UHF" and leave the base offset information blank.....

load that into your scanner and see if works.....it should lock onto the current control channel
 

loumaag

Silent Key - Aug 2014
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Please stop referring to the system as a Motorola Type-II, it is not. It is a standard P25 9600 baud system. You are confusing yourself right from the start if you are looking at options for the system when you have the software set to 'Type-II' mode.
...
Really, if you aren't following this conversation, you really need to stay out of it. Since you posted directly after me, I assume you are referring to my instruction to set it to Moto Type II for VHF or UHF for a VHF or UHF P25 system. Up at the top of the topic, it was clear the system in question was a P25. You apparently really have no idea how a 796D is programmed; if you think I gave the wrong instruction, I am pretty sure you have never programmed a 796D for a P25 VHF or UHF system.
 

2WAYMAN

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New Jersey
Excel sheet from scanner dude ke4pjmj???

4-25-12 11 PM EDT
Hello all......
In regards to the topic at hand.......In the Motorola forum there was a post regarding an Excel Spreadsheet
which was apparently designed by Brian Cathcart also known as ScannerDude KE4PJMJ which deals with determining base, offset and step for Motorola UHF/VHF trunking systems when you know at least one control channel frequency..
Does anyone here know Brian and or how to contact him? Or, does anyone happen to have a copy of his Excel sheet???
All assistance is greatly appreciated .
Thanks and 73's
 

loumaag

Silent Key - Aug 2014
Joined
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Messages
12,935
Location
Katy, TX
4-25-12 11 PM EDT
Hello all......
In regards to the topic at hand.......In the Motorola forum there was a post regarding an Excel Spreadsheet
which was apparently designed by Brian Cathcart also known as ScannerDude KE4PJMJ which deals with determining base, offset and step for Motorola UHF/VHF trunking systems when you know at least one control channel frequency..
Does anyone here know Brian and or how to contact him? Or, does anyone happen to have a copy of his Excel sheet???
All assistance is greatly appreciated .
Thanks and 73's
I may have a copy buried in some archive around here, but Wayne (staff member here) has one that does basically the same thing on the RR WIki. Go to this page and then scroll to the bottom, it is the last link in the actual article.

However, I need to point out that neither Wayne's nor Brian's spreadsheet has anything to do with the subject at hand. Those are used to calculate the base, step, offset for UHF and VHF Moto Type II systems. For a UHF or VHF P25 system and a 796D, you just need to put anything in the table as it will be ignored, the default that comes up is fine. Actual P25 table numbers will not load in the 796D table.
 
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