A. How to determine the pre-attenuation (for TX and RX)
The pre-attenuation values can be determined for a specific phone model. You will need a properly working phone with a fully loaded battery, a suitable RF adapter and an RF cable, the Universal Antenna Coupler and a 410x or 420x Series Mobile Service Tester.
Start the 4100/4200 in Fault Find mode and select the appropriate system(s) (i.e. frequency bands).
Select a frequency channel on which you intend to test.
Connect the mobile to the tester using the RF adapter and the RF cable.
Select medium power levels for RX and TX (power level step 9 to 11, RF level at –80 dBm).
Set the pre-attenuation values to 0 dB.
Start a test.
Note down the results for MS Pwr and RX Level.
Repeat the measurements for the other frequency channels that you intend to test.
Remove the RF adapter and connect the Universal Antenna Coupler instead.
Place the mobile on the coupler and fix it.
Repeat the above measurements.
For all the different channels, calculate the difference between the results (measurements with the RF adapter versus those with the Universal Antenna Coupler, both for TX (MS Pwr) and RX (RX Level). This gives the pre-attenuation.
Select AUTOTEST, CONFIG and then INSERT to define and save the mobile name with the related parameters.
Start the AUTOTEST for the new mobile type and check for proper operation.
