Nokia RM-94 Rf Troubleshooting Instructions page 33

RM-94
6(b) - RF Troubleshooting
Figure 3:Typical frequency tuning curve for the FDK VCO
4500
4000
3500
3000
0 0.5
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.
Issue 1 04/2005
Temperature: +25°C
1 1.5 2
2.55V @ 24.4 .. 25.4°C
High limit
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Copyright © 2005 Nokia. All Rights Reserved.
2.5 3 3.5 4
VCTRL [V]
2.7V @ 24.4 .. 25.4°C
Low limit
Nokia Customer Care
4.5 5 5.5 6
2.85V @ 24.4 .. 25.4°C
33