Motorola RF Amplifier quick start Above 110ºF, Below 32ºF

4STARLINE

5Verify that the input level agrees with the design specification input. If the level is different from design, adjust accordingly.

For example: the design level is 19 dBmV at the highest frequency and the design pad value is JXP-3B. If the actual measured level is 21 dBmV, then you must change the pad to a JXP-5B.

If the actual levels are significantly different from the design levels, it is recommended that you investigate or consult system management before proceeding.

6Connect the signal level meter to the output test point and tune the meter to the high-end channel.

7Turn the manual gain reserve (MAN) control to maximum (fully clockwise) and then reduce the output by the amount indicated below:

Amplifier	Above 110ºF	32ºF to 110ºF	Below 32ºF
BLE*/*	3 dB	4 dB	5 dB
MB*/*	4 dB	5 dB	6 dB
BT*/*	4 dB	5 dB	6 dB
MBE*/*	3 dB	4 dB	5 dB

8Check the amplifier output tilt by measuring the high band- and the low band-edge carriers:

!High = channel 116 (745.25 MHz) or channel 136 (865.25 MHz)

!Low = channel 2 (55.25 MHz) or channel 3 (61.25 MHz)

!If the tilt is less than required, install a higher value SFE-*-*

!If the tilt is greater than required, install a lower value SFE-*-*

!If the high value equalizer provides too much tilt and the low value equalizer provides too little tilt, use the lower value equalizer. Under-equalization is preferential to over-equalization.

9You must adjust the input pad if you use a STARLINE Cable Simulator (SCS-*) and the design value is changed.

For each 1 dB increase in SCS-*value, 1 dB of loss is introduced at 750 MHz or 1.1 dB of loss at 870 MHz. Therefore, to maintain a proper gain level it is necessary to adjust the input pad value as follows:

!For each increase in SCS-*value, decrease the input pad by 1 dB.

!For each decrease in SCS-*value, increase the input pad by 1 dB.

!If you replace an SFE-*-*with an SCS-*, reduce the value of the input pad by the value of the SCS-*.

10Measure the output level at the highest frequency. It should be within 1 dB of the system design level. If it is not, you must adjust the interstage pad and/or the output pads accordingly.

The input pad is normally changed to accommodate excessive input levels. Because it only attenuates excess signal, it has no effect on the overall performance of the amplifier.

RF Amplifier Quick Start Guide