Technical Manual

Table Of Contents

Tuning

There are only three tuning elements to be acted upon: FL3, L6 and L10. Their loca-

tion on the PCB (all upper side) is depicted in the schematic below:

3.3.2. Test Equipment Settings

Before proceeding, certain controls on the test equipment must be set; some of the

settings depend of the operating band (high or low) of the device under test (DUT).

In addition, it is highly recommended that the ambient temperature during trim-

ming is 24° C (±2°C).

3.3.2.1. Network Analyzer (HP 8711)

The settings for the Network Analyzer are as follows:

• Center frequency: 450 MHz

• Span: 100 MHz

• Display: 5.0 dB/div

• Power: -20 dBm

• Markers:

— low band Mkr1 – 440 MHz, Mkr2 – 430 MHz, Mkr3 – 450 MHz;

— high band Mkr1 – 460 MHz, Mkr2 – 450 MHz, Mkr3 – 470 MHz.

Note: A good idea is to store the instrument state for the two settings, low band and high band.

3.3.2.2. Service Monitor (Rohde & Schwarz CMS50)

The setting for the receiver section check are as follows (RX-TEST):

• SET RF: 432000000 Hz (Low band) / 450000000 Hz (High Band);

• RF LEV: 5 µV (see also note below);

• SINAD;

• AF1: 2kHz;

• MOD1: 3.5 kHz;

• SCOPE MODE;

• BEST RANGE.

FL3

L10