LTR Channel Schemes

[GlacierClipper]

Here are the normal LCN Schemes for programming an LTR system.

LCN 1, 5, 9, 13, 17

LCN 4, 8, 12, 16, 20

LCN 2, 6, 10, 14, 18

LCN 3, 7, 11, 15, 19

Some LTR systems are programmed with the highest frequency as being the first LCN.
There are many LTR systems that have the lowest frequency as being the first LCN.
A few LTR systems does not have an certain type of frequency order.

 

[WayneH]

I wish all systems were that normal. Nowadays they don't need to follow those arrangements due to the data buss restrictions that used to exist, and required the gaps.

-Wayne

 

[DaveH]

I don't believe the gapping was so much due to the controller internals
as it was to allow HR "aliasing". Trunked channel groups (at least in the
US) seem to have been handed out in 5-channel increments. The gaps
were meant to allow itinerant mobiles who did not have a valid HR on
a system they were visiting (legitimately), to be "aliased" onto an existing
HR. Spreading out the channels that way allowed for maximum flexibility.
And if two or more smaller systems ended up merged, if they had
non-overlapping plans, might make things a bit easier.

As for HR numbering, I've seen everything: reverse-ordered by-5,
systems with different plans merged or HRs added, and some with
increments of 1.

Dave

 

[BirkenVogt]

The channel gaps are there because the "free" repeater is determined by which one last transmitted on the bus. If they are all bunched up 1,2,3,4,5 then number 5 gets by far the most "free" hits because it also gets used for slots 6,7,8,9,10,11...20. Now if you spread those 5 out on 1,5,9,13,17 then 1 gets slots 1,2,3 and 4. 5 gets slots 5,6,7, and 8. And so on. That way they all get relatively even loading.

Newer controllers have nothing to do with it, if it is LTR it follows this format, period. Some of the legacy stuff is quite restrictive in this way.

Frequency has nothing to do with anything really, the controller has no idea what frequency the radio is on.

Birken

 

[joespca]

Hi any one here know the FM communicationsLTR system frequencies?

 

[Saint]

FM Comm Frequencies

Hi any one here know the FM communicationsLTR system frequencies?

The Frequencies for Fm Communication Systems are in the data base on this web site, all 7 different systems, is this not what your looking for ??, several people are working on posting the information for these 7 systems.\
Steve

 

[joespca]

Ltr system

i am lookinf for the ither system frequencies found on this link
http://www.radioreference.com/modules.php?name=RR&sid=4704

 

[DaveNF2G]

Don't hijack threads!

You've already asked about this in the New York forum, which is the correct place for your question. Do you think everyone's trying to keep the frequencies secret or something?

 

[DaveH]

i am lookinf for the ither system frequencies found on this link
http://www.radioreference.com/modules.php?name=RR&sid=4704

How do you know there are any "missing" frequencies? Just because there are
gaps in the channel numbers, does not mean they exist. That's just the way LTR
works. I see only groups homed on channel 11 listed, and that channel is known.

Dave