#### rananthony04

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-Robert

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-Robert

In the Win96 Help file there is this nasty formula when discussing Extended Trunking Tables: Voice Frequency = Base + [(channel – Offset) x Step]

This same formula is used in this most excellent but mind-numbing Wiki:

http://wiki.radioreference.com/index.php/Determining_Base/Step/Offset_for_VHF/UHF_Motorola_Systems

It seems that Lo and Hi are pertaining to the "channel numbers" in a system. The Wiki describes that 0-379 are dedicated for 'receive' and '380 -759' are for transmit. So it starts with 380 and can't go past 759, IMHO. Also something about the channels cannot overlap

I created a spreadsheet for the formula: Base + Channel + Offset = Frequency.

480.5000 + Some Number + .0125 = 482.0875 (your first channel)

I started with 380 and I worked up from there.

I found that

480.5000 + 507 + .0125 = 482.0875 (first channel)

through eventually where

480.5000 + 681 + .0125 = 484.2625 (last channel)

I think that solves Glendale, Monetbello, & Oat Mountain.

For Burbank I programmed in

470.0125 + Some Number + .0125 = 470.0625 (first channel)

and right away I found that

470.0125 + 384 + .0125 = 470.0625 (first channel)

through

470.0125 + 402 + .0125 = 470.2875 (last channel)

So you'd create a Customized Fleet Map as follows:

Lo: 384 || Hi: 402 || Base 470.0125 || Offset 380 || Step 12.5

Lo: 507 || Hi: 681 || Base 480.5000 || Offset 380 || Step 12.5

Again, w/o Trunker S/W, this is just a good guess. And you are on your own for Pomona.

HTH, Mike

If the base does start (we don't know without the hex value) at 407.0125 and the step is 12.5, then the last channel in the 470 MHz freq range is channel 402.

470.2875 - 470.0125 = .275 / .0125 = 22 channels. The next channel (403) is the base channel of the second group, 480.500 (assuming it's hex is correct). Using the same math as in the previous table, then 484.2625 - 480.500 = 3.7625 /.0125 = 301 channels. 301 channels + 22 channels = 322 channels which falls within the range for Motorola tables. Thus all 5 sites are covered.

Lo:

Lo:

And of course, if the coverage is from 380 to 759, the second table Ch Hi should be 759.

My 2 cents.

Thanks again

-Robert

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