UBCD396XT
41.Calculating upper base frequencies
Custom Band Plans (800 Custom, VHF, UHF) require that you enter both a lower and an upper base frequency value. Here's how to determine these values.
The Lower Base Frequency (or Base ) is always the base frequency as provided in the RRDB. The Upper Base Frequency is calculated from the following formulas:
For sites with a single band plan:
Base + ( (759 – Offset ) × Step )
Where:
∙Base = the lower base frequency listed in RRDB.
∙Offset = the offset for this entry.
∙Step = the step for this entry.
For sites with multiple band plans:
Upper Basen = Basen + ( Offsetn+1 – 1 – Offsetn ) × Stepn
Where:
∙Basen is the lower base frequency for the entry.
∙Offsetn+1 is the Offset for the next band plan (for the last table, use 760)
∙Offsetn is the offset for this band plan
∙Stepn is the step for this band.
For example:
Custom Frequency Table
Entry | Base | Spacing | Offset |
|
|
|
|
A | 155.4150 | 15.0 | 380 |
|
|
|
|
B | 157.2000 | 12.5 | 436 |
|
|
|
|
C | 157.4700 | 15.0 | 454 |
142
