User Guide

CCS Technical Documentation Troubleshooting — RF
RH-17
Issue 1 04/2003 Nokia Corporation Confidential Page 37
Manual Verification:
Set the phone to local mode and turn on the AMPS transmitter to the channel which
failed on Power Level 2. (adjusting for cable loss).
Troubleshooting:
Troubleshoot the cell transmitter as described in Table 2, setting the TX AGC values to
those listed for Power Level 0 in Table 1.
Tests 111 - 115 TN AMPS PL3 (or 4, 5, 6, or 7) Po
Description:
This procedure tunes power levels 3 through 7, all on the center channel. Power level 0
was tuned in the previous test. (Power levels 0, 1 and 2 are the same for this phone.)
Explanation of Result:
The result is measured transmit power in dBm for power levels 3 through 7 on
channel 384.
Manual Verification:
Use the same procedure as in previous tuning, but on channel 384 selecting correspond-
ing Power Level. Note that the limits are different from the previous tuning.
Troubleshooting:
Troubleshoot the cell transmitter as described in the beginning of this document, setting
the AGCs as in Table 1 for the power level which failed.
Test 118 TN TX DC Offset Carrier Suppression
Description:
The DC offset voltages on the I and Q inputs to the modulator are adjusted for minimal
carrier feedthrough (maximum carrier suppression). Initially the DC offsets are set to a
nominal value, and the power of a tone offset in frequency 20 kHz from the carrier is
measured in dBm and recorded as a reference (in this tuning). Then in the next tuning,
the carrier suppression (delta between center tone and tone that is offset 20 kHz) is
measured. If it passes, it is reported in that tuning. If not, the DC offsets are adjusted
until it passes, and the passing value is reported. This step reports the delta between the
reference at 836.52 MHz + 20 kHz, and the minimum carrier level at 836.52 MHz.
Explanation of Result:
The result is a delta in dB between the reference at 836.52 MHz + 20 kHz, and the mini-
mum carrier level at 836.52 MHz, found by adjusting the DC offsets for I and Q individu-
ally. The delta should be at least 35 dB.
Manual Verification:
Set up the phone as in the next Test 119 , and record the reference power of the offset
tone. Measure the delta between the center and offset tones. If the delta is 35 dB or
greater, the phone passes. If less than 35 dB, vary the "I" DC offset on the "values" line in