User Guide

Issue 1 04/2005 COMPANY CONFIDENTIAL 33
Copyright © 2005 Nokia. All Rights Reserved.
RM-94
6(b) - RF Troubleshooting Nokia Customer Care
Figure 3:Typical frequency tuning curve for the FDK VCO
Even if the PLL is not working properly (Vc outside the valid range), a frequency at the output
of the VCO can be detected between 3GHz and 4.4 GHz (if the VCO itself is ok and the supply
voltage VR7 = 2.78V is applied).
If the frequency or the tuning voltage have other values than given above, see the fault finding
chart for PLL syntesizer below.
Temperature: +25°C
3000
3500
4000
4500
00.511.522.533.544.555.56
VCTRL [V]
Frequency [MHz]
2.55V @ 24.4 .. 25.4°C 2.7V @ 24.4 .. 25.4°C 2.85V @ 24.4 .. 25.4°C
High limit Low limit