246 and splintering above 866.0

[Jay911]

Hi all,

As some of you may have seen already, a colleague here in Alberta is having a hard time getting a particular trunk system (City of Red Deer) to track in his 246. All indications point toward this being a splinter system, except that most people seem to maintain that no splinter channels exist above 866.0 mhz. The 246 appears to not track this system either, from what jaythescanman is saying. It shows TG info if it locks onto the control channel, but is trying to move to the wrong channel 0.125mhz too high (i.e. 867.6125 vs actual freq 867.0500).

I haven't been in Red Deer myself for a while, but I think my BC250D worked there, and I thought my 396 did just fine - but I could be wrong. Are there any other examples of "splinter" systems above 866 having issues with the 246 and/or 396 (and associated family of scanners)? If so, any chance of a fix?

 

[slicerwizard]

(from the original thread)

My bad. Lack of coffee error. No, that isn't a splinter system. Splinter systems are 800 MHz systems whose frequencies below 866 MHz end in .xxx0 rather than .xxx5; Since that system doesn't have any frequencies below 866 MHz, one should be able to program it as a spliter system or as a regular system and everything should work fine.

However, the earliest firmware versions for the 246T didn't handle systems with frequencies above 866 MHz properly (they had to be created as splinter systems, even if they weren't, otherwise entry of frequencies above 866 MHz was rejected ("Out of Band"), which also led to off-by-12.5kHz errors!)
If the scanner isn't running the latest firmware (2.05), it should be upgraded. If it is running 2.05, then it sounds like the problem hasn't been fully fixed.


Motorola 800 MHz band channel numbering (repeater outputs):

Standard plan:
Channel 1: 851.0375 ... Channel 599: 865.9875 (25 kHz steps)

Splinter plan:
Channel 1: 851.0250 ... Channel 599: 865.9750 (25 kHz steps)

Extended band:
Channel 600: 866.0125 ... Channel 719: 868.9875 (25 kHz steps)
Channel 720: 866.0000 ... Channel 1022: 868.9500 (25 kHz steps)


The system in question has channels in the 720 to 1022 range (but the 866.0300 entry is invalid - someone messed that one up); Current 246T firmware handles channels 1 to 719 properly; I don't know if it works properly with 720 through 1022.

 

[Jay911]

If the scanner isn't running the latest firmware (2.05), it should be upgraded. If it is running 2.05, then it sounds like the problem hasn't been fully fixed.

Sounds like it isn't, then. jaythescanman reports his 246 has ver 2.05 firmware.

He sent out his Unitrunker files and they report the channel numbers as follows (in decimal), with a band plan supplied by rfmobile, tweaked by me:

602 - 866.0500
612 - 866.3000
622 - 866.5500
642 - 867.0500
662 - 867.5500
682 - 868.0500
702 - 868.5500

(With the standard band plan, it was reporting the same channel numbers, with the resultant frequencies 0.0125mhz higher.)

Channel 720: 866.0000 ... Channel 1022: 868.9500 (25 kHz steps)

Okay! THAT is what he needs. Starting at 866.0 instead of 866.0125. But if Unitrunker is reporting 602 for 866.05, doesn't that imply the trunk controller is sending out references to ch 602 and not ch 722?

(but the 866.0300 entry is invalid - someone messed that one up)

That was my fault. I was adding the previously unknown 866.3000 freq and had too much 866.05/867.05/etc on my brain. Fixed now in the DB and elsewhere.

On one hand this sucks if it's a firmware issue, but on the other hand at least it'll be fixable, presumably. Do you know if the same problem befalls the 396 and 996?

 

[jaythescanman]

guess I sit and wait...It sucks I spent so much money on it for it just to simply not work how its supposed to

 

[slicerwizard]

It looks like some systems don't follow the band plans I posted, e.g. they use channel indexes 600 to 719 for .xxx0 frequencies, when we'd expect to see them refer to .xxx5 frequencies. I guess there's a flag for this in newer Motorola programming software.

Uniden's left hand (which makes the traditional scanners), seems to be aware of this and provides four band plans for 800 MHz systems:

Plan # Main Extended
Plan 1: .xxx5 .xxx5
Plan 2: .xxx5 .xxx0
Plan 3: .xxx0 .xxx0
Plan 4: .xxx0 .xxx5

[if any of that is wrong, blame their horrible manuals ("If the last three digits of frequencies are less than 869.0000....") WTF does that mean?]

So plan 2 or 3 might work.

Uniden's right hand (the 246/330/396/996 crew) does not seem to be up to speed on this issue. AFAIK, all of those models only do plan 1 (standard) and plan 4 (splinter).

So I guess it means firmware upgrades for all of those models. I wonder how they'll handle it? Either two new system types or an additional entry in the system options menu. Time to upgrade UASD and ARC software as well.

 

[slicerwizard]

guess I sit and wait...It sucks I spent so much money on it for it just to simply not work how its supposed to

Yup, you're boned. At least you don't have a 396 or 996 doorstop.