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Uniden Band Plan Entry

From The RadioReference Wiki

Custom Band Plans for Analog or Digital or Mixed Mode (Analog & Digital i.e. Motorola Type II) Trunk Systems require that you enter both a Lower and an Upper Base Frequency value.

Though, APCO P25 Phase I and II systems do not usually require a Band Plan, as it should be carried on the Control Channel, for a slightly distant Site, reliable/initial Reception and Decode may require a "Manual entry" of Custom Band Plan. Here's how to determine these values.

For Site(s) with a single band plan:

Lower Base Frequency: Base Frequency as provided in the RRDB
Upper Base Frequency: Lower Freq + (759-Offset) *step

For Sites with multiple Band plans, you need to calculate the upper base frequency for each entry: Upper Basen = Basen + (Offsetn+1 - 1 - :Offsetn)*Stepn

Where:
  • Basen is the lower base frequency for this 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 Band Plan Frequency Table

Base Spacing Offset
155.4150 15.0 380
157.2000 12.5 436
157.4700 15.0 454
Lower Base 1 = 155.4150 MHz
Upper Base 1 = 155.4150 MHz + (436 - 1 - 380) * 15kHz
Upper Base 1 = 155.4150 MHz + 55 * 15kHz
Upper Base 1 = 155.4150 MHz + 0.825 MHz = 156.2400 MHz
Lower Base 2 = 157.2000 MHz
Upper Base 2 = 157.2000 MHz + (454 - 1 - 436) * 12.5 kHz
Upper Base 2 = 157.2000 MHz + 17 * 12.5 kHz = 157.4125 MHz
Lower Base 3 = 157.4700 MHz
Upper Base 3 = 157.4700 MHz + (759 - 454) * 15 kHz
Upper Base 3 = 157.4700 MHz + 305 * 15 kHz = 162.0450 MHz


Typically, Custom Band Plan APCO25 Phase I & Phase II: 700mhz and/or 800 mhz may be needed to be entered for the fringes of a systems, as newer System may have their towers point inward (to only cover their jurisdiction, avoiding interference with neighboring jurisdictions). For initial proper 'Reception & Decode' may need the Custom Band Plan set by the user - short of moving closer with the scanner to a single tower. Additionally, adjustment of P25 audio decode level adjustment to Manual mode may be necessary - if you can't reliably receive and decode a System's Site(s) data and voice.

Typical Custom Band Plan for a 700mhz Phase I System

Position Base (Mhz) Spacing
0 851.012500 12.5 khz
1 762.006250 12.5 khz

Typical Custom Band Plan for a 800mhz Phase I System

Position Base (Mhz) Spacing
0 762.006250 12.5 khz
1 851.012500 12.5 khz

Typical Custom Band Plan for a 700mhz Phase II System

Position Base (Mhz) Spacing
0 851.006250 6.25 khz
1 762.006250 6.25 khz
2 851.012500 12.5 khz
3 762.006250 12.5 khz

Typical Custom Band Plan for a 800mhz Phase II System

Position Base (Mhz) Spacing
0 762.006250 6.25 khz
1 851.006250 6.25 khz
2 762.006250 12.5 khz
3 851.012500 12.5 khz

Now, it may seem counter-intuitive that each P25 Custom Band Plan(CBP) not only starts at Position 0, and includes a frequency-range that 'seems' to be 'un-needed', as well as starting with that 'un-needed' frequency-range first, manual entries may need to be made to start to monitor a distant (yes, +1mi or more) Phase I or II system (or another CBP). Some users, have even noted in the 6th or 7th position a unique frequency-range appearing in the Band Plan after decent-to-quality reception (or in any Position for that fact) of a System's Site; these anomalies are not unusual. Hence, why in many Forums Users ask, "have you tried to drive close to 'tower x' with 'scanner y', while, some do not realize not everyone wants to drive around with a $500 scanner on their passenger seat to get the proper "Band Plan" for their "Desktop" scanner. As well, it's a "User Best Practice" to update their Firmware before any reception or decode issues are noted/posted in the Forums.

For more Info See our Rebanding and Uniden Scanners article and our Software Support for Uniden Rebanding



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