User Guide

PAMS
Technical Documentation
WinTesla User Guide
NHD–4
Page 38
Original 11/97
Rx Slope
The purpose of this tuning operation is to calibrate the linear relationship,
or slope, between a change in the received power by the CDMA receiver.
This tuning is needed if the duplexor, CDGACR (N1), CDSB (D704),
CDRFI (N700) or BBFIL (N2) is changed.
Definition of Tuning
This tuning determines the linear relationship, or slope, between a change
in the received power by the CDMA receiver. To do this a CW signal is fed
into the CDMA receiver. The initial CW signal power is stored as BPOW1.
Next, the CW signal power is incremented until the RxCtr changes by 256
steps. The CW signal power required to do this is recorded as BPOW2.
The difference between BPOW1 and BPOW2 should be approximately 32
dB. From this data the RX Slope is determined. It is then manipulated
mathematically so that the RX Slope equals “1”. When it does, a one bit
change in the RxCtr will result in a 1/8 dB change in receiver gain. The
RX/TX designator on the name of this tuning implies that the transmitter is
on when this tuning is performed. A separate tuning must occur when the
transmitter is not on, hence the reason for the RX_Slope (RX) tuning.
Rx Slope calibration steps & equipment:
– Using the JBS–7 service jig, replace the standard battery of the phone
with the dummy battery BTS–4.
– Apply +6.0 V to dummy battery.
– Select ” Tuning – Rx Slope”
– Set up the signal generator as requested and press the step 1 key.
– Change signal generator set up as requested and press the step 2
key.
– Press <save & exit> to store value to EEPROM or <cancel> to exit
without saving.