Tuning A 700/800 Mhz Duplexer; Tuning A Vhf Duplexer; Vhf Duplexer Tuning Setup - Motorola ASTRO 25 GTR 8000 Manual

MN003286A01-E
Chapter 5: GTR 8000 Base Radio Optimization
• Tuning tool (thin blade) (VHF)
• N-to-N bullet connector (UG29A/U or equivalent)
• 7/16-inch Nutdriver (UHF)
• 7/16-inch Open End Wrench (UHF)
• N-to-BNC Adapter (UG349A/U)
• N-to-N Connector (UG57B/U)
5.10.3

Tuning a 700/800 MHz Duplexer

No field tuning is needed on a 700 MHz or 800 MHz duplexer. The duplexers are pre-tuned to operate
over the entire sub-band.
5.10.4

Tuning a VHF Duplexer

The following procedures are most easily performed with the duplexer module removed from the rack
or cabinet. Know the transmit and receive frequencies for the particular base radio before beginning.
If the duplexer module is tuned according to instructions and does not meet specifications for return
loss, insertion loss, and/or isolation, the duplexer must be returned to the Motorola Solutions Support
Center (SSC) for repair.
5.10.4.1

VHF Duplexer Tuning Setup

Perform the tasks in Setting Up for VHF Duplexer Tuning on page 167
module. See Figure 61: VHF Duplexer Tuning Setup on page
166
before tuning the VHF duplexer
167.