396t Other Settings!

[Larryfire26]

I would like to know if you need the following settings set:
base freq, step and offset and how do you determine what those numbers are if there not listed?

also do you need to adjust the hold time to 8, what about the enable i-call is this needed?

now we go to the apco band plan what if any info do you need to enter in there?

LCN is ok as thats understandable as is the control channel.

any help is appreciated

thanks all

 

[UPMan]

1) Base, freq and offset are needed for UHF and VHF Motorola Type II systems.
2) If you adjust hold time to 8, the scanner will stay on that system for 8 full seconds before moving to the next system. Most people set it to "0".
3) Enable i-call if you want to receive i-calls.
4) 99% of APCO 25 systems do not require a band plan to be entered.

 

[dgoodson]

If you program base/step/offset for a UHF Trunk system, then do you still need to program the individual site frequencies?

I guess I don't understand the relationship betweeen the purpose of the Band Plan data and individual frequencies.

 

[UPMan]

With the base/step/offset entered you need to program at least the control channel frequencies. The base/step/offset values are used by the scanner to convert the channel number sent on the control channel to an actual voice channel frequency.

 

[N9NRA]

Just was reading this thread, and i too was wondering as i`m looking at programming some VHF/UHF trunked systems in this area. Question for ya Upman, if i read your post right, then i can use the C-Channel only mode with these systems (VHF/UHF MOT type 2 systems) as well? Thanks! Your hard work is most appreicated ! N9NRA

 

[UPMan]

Correct. In any event base/step/offset is required. If you don't want to use the trunking activity indicators feature, then entering the voice channels are optional.

 

[ka3jjz]

Paul, since we're talking about 'other settings' here, it's not too much of a hijack...

On the 396, do you still need to change the AGC settings one at a time? In the previous firmware, you had to disable the digital AGC to modify the analog AGC, and vice versa. What about the 996?

73 and thanks Mike

 

[UPMan]

Yes and Yes. (I could swear I've seen this asked and answered today...but couldn't find it. Feels a bit like Bill Murray in Ground Hog day.)

 

[dgoodson]

What do the Base/Step/Offset "numbers" signify, particulary "offset" with a range of 380 to 759? I can guess that "base" + some_number x "step" tells the radio which frequency to hop to for a Talkgroup, but it isn't obvious to me what the value represented by "offset" would be used for.. maybe an offset in teh digital message on the control channel where the frequency info is held or soemthing like that? just curious.

 

[slicerwizard]

The offset value indicates the starting channel number for a defined range of channels. 380 is a common value because it's the lowest repeater output channel number used on Motorola VHF/UHF systems (0 to 379 are repeater input channels, which scanners tend to ignore)

The step size indicates how far apart (in kHz) adjacent channels are and the base frequency is the starting frequency for the range.

So if base=400 MHz, step=15 kHz, offset=380,

channel 380=400.000
channel 381=400.015
channel 382=400.030
etc.


Motorola VHF/UHF systems support three ranges for repeater inputs and another three for repeater outputs.

 

[bwilborn]

The offset value indicates the starting channel number for a defined range of channels. 380 is a common value because it's the lowest repeater output channel number used on Motorola VHF/UHF systems (0 to 379 are repeater input channels, which scanners tend to ignore)

The step size indicates how far apart (in kHz) adjacent channels are and the base frequency is the starting frequency for the range.

So if base=400 MHz, step=15 kHz, offset=380,

channel 380=400.000
channel 381=400.015
channel 382=400.030
etc.


Motorola VHF/UHF systems support three ranges for repeater inputs and another three for repeater outputs.

Ahh, I think I see. The most confusing thing to me was figuring out what the 'offset' was. Basically what you're saying is that the channel is more of an index than a frequency, kind of similar to an LCN on an EDACS system?

-- B