[Scan-DC] rebanding status comment from Lt. Dallas Lipp

[Jeff Krauss]

Posted on radioreference.com by Lt. Dallas Lipp, Montgomery County 
Fire and Rescue Service:


"MC has hit a snag in the rebanding process. As the techs started the 
frequency realignment process (the actual act of rebanding the 
system) they noticed significantly degraded performance on some of 
the new frequencies at some sites. Further investigation determined 
that there are filters on the tower top amplifiers on some sites that 
are significantly degrading performance on some of the new 
frequencies. As a result of this discovery the channels that had been 
realigned have been moved back to their old assignments until a 
solution to the filter issue can be implemented.

All of that said, Fire/Rescue has moved from the legacy zones in the 
radios (zones marked with an "*") to the rebanded zones (no "*"). The 
reason we have made this change is that concurrent with the rebanding 
of the system we had to transition from our existing VRSs (Vehicular 
Repeater Systems) to new DVRSs (Digital Vehicular Repeater Systems). 
The old VRSs would not support the new frequency assignment so we had 
to install new DVRSs that would support the frequency.

We could not roll back (nor we we want to roll back even if we could) 
the VRS/DVRS transition when the system rebanding hit the snag. As a 
result once the majority of the DVRSs had been installed we advised 
our users to start using the "non-*" zones on the radios all of which 
have the new DVRS frequencies programmed; by doing this we ensure 
that our users can continue to use the DVRSs to enhance coverage when needed.

What this means to those scanning the system is that the old 
frequency assignments are still in use and will be for some time to 
be determined.(a resolution plan is being developed today). That 
said, as a result of the VRS/DVRS transition MCFRS will be operating 
exclusively on the "non-*" (post-rebanding) zones from this point 
forward. On the trunked side of the rebanding equation the talkgroups 
work regardless of what frequency is in use or where the talkgroup is 
selected in the radio (* or non-* zones in MCFRS radios). What 
impacts the user are the conventional channels embedded in each zone; 
those have to match or stuff doesn't work.

For those that are not familiar the DVRSs (or previously VRSs) are 
conventional repeaters that are interfaced to the trunked radio 
system. This allows a user who is out of range of the trunked system 
to switch to a conventional channel and continue to communicate with 
users on the trunked system and vise versa.

In addition to the DVRSs using the new channel assignments, the 
conventional channel that we use exclusively as a simplex talk-around 
channel (7 Oscar) has also moved to the new channel assignment in the 
"non-*" zones.

Hope this helps to unscramble some of the understandable confusion."