[Repeater-Builder] LTR Rocks !
Kinda off track for a Ham repeater group, but been there done that. Mine was due to loss of 800 SMR channels when they were easy to come by, then later impossible to get due to freezes. Exclusivity. You need at least one repeater that has exclusive use in a service area because LTR uses centralized control and the HOME repeater needs to be exclusive. Having the second repeater also exclusive is a big plus. Next narrowband vs wideband. Depending on location you may be narrow band - that seems to work OK. You need two repeaters and controllers. Some repeaters like the Johnson VX have logic built in. Others use IDA, RLC, Trindent, Zetron Model 42, etc. You should be able to handle 6 to 10 groups of 10 to 15 radios pretty comfortably - probably more. The curve for users vs channels is exponential as adding a channel makes much more capacity than one channel by itself. Best success, Steve NU5D wadeds2003 wrote: Hello group. Just looking at putting up a ltr system. I would like to go 2 channels for now just to see how it all works. My plan is to use it for my business plus sublease some space to other companies. Has anyone here ever tried a 2 channel ltr system before? How does it work compaired to a larger system? A tech over at trident told me not to waste my time with a 2 channel system as he said it would not work but I have talked to other people who have done 2 channel systems and
Re: [Repeater-Builder] LTR Rocks !
Steve S. Bosshard (NU5D) wrote: Kinda off track for a Ham repeater group, but been there done that. Mine was due to loss of 800 SMR channels when they were easy to come by, then later impossible to get due to freezes. Exclusivity. You need at least one repeater that has exclusive use in a service area because LTR uses centralized control and the HOME repeater needs to be exclusive. Not quite true. LTR does not use a control channel, and does not transmit continuously, however, if you do not have exclusivity on a channel-ANY channel-you need a monitor rx on the output cross-connected so that it prevents that channel from keying if it hears other traffic. Having the second repeater also exclusive is a big plus. Next narrowband vs wideband. Depending on location you may be narrow band - that seems to work OK. 512 MHz and down to 136 or whatever will all be narrowband by 2013 anyway, except I haven't seen provisions for it for part 95 (GMRS) yet, so it will likely be exempt. -- Jim Barbour WD8CHL
Re: [Repeater-Builder] LTR Rocks !
LTR indeed does not use a dedicated control channel like EDACS or PP - control is distributed. Subscriber units are programmed to seek a HOME repeater and if it is not available (busy channel inhibit) the radios homed to that repeater are dead. When the home repeater is servicing a call it at the same time tells subscriber units to find a new home on RPT #X and will continue to send that data word even after the user on the home repeater is finished, so long as the transmission continues on the new home to service late entry. LTR is considered by the FCC as centralized trunking. De-Centralized trunking lets mobile units decide when to transmit. LTR does not have a provision for the mobile radios not to transmit on a busy channel. In centralized trunking, the site orchestrates mobile transmissions. But I may be wrong, Steve NU5D Jim wrote: Steve S. Bosshard (NU5D) wrote: Kinda off track for a Ham repeater group, but been there done that. Mine was due to loss of 800 SMR channels when they were easy to come by, then later impossible to get due to freezes. Exclusivity. You need at least one repeater that has exclusive use in a service area because LTR uses centralized control and the HOME repeater needs to be exclusive. Not quite true. LTR does not use a control channel, and does not transmit continuously, however, if you do not have exclusivity on a channel-ANY channel-you need a monitor rx on the output cross-connected so that it prevents that channel from keying if it hears other traffic. Having the second repeater also exclusive is a big plus. Next narrowband vs wideband. Depending on location you may be narrow band - that seems to work OK. 512 MHz and down to 136 or whatever will all be narrowband by 2013 anyway, except I haven't seen provisions for it for part 95 (GMRS) yet, so it will likely be exempt.
