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nion, 02/19/2016 10:48 PM
add background information on filter replacement

Motorola filter replacement

In order to use the phone as a passive uplink sniffer or even as a BTS, you will have to remove and replace the RX filters.

To replace filters on Motorola phones you will need:

As the shipping cost for such a small-quantity order is relatively high, a complete component kit is
available for online order from

=== Remove existing baluns ===

First you will need to remove existing balun:

Image(motorola_filter_replacement_step_1_low.jpg, 250px)
Image(motorola_filter_replacement_step_2_low.jpg, 250px)

=== Solder new baluns ===

Clean up the phone and solder HHM1526 and HHM1523C1 on the right places (the black dot goes up):

Image(motorola_filter_replacement_step_3_low.jpg, 250px)
Image(motorola_filter_replacement_step_4_low.jpg, 250px)
Image(motorola_filter_replacement_step_5_low.jpg, 250px)

=== Solder ceramic capacitors ===

Last step is to solder ceramic capacitors 04025A150JAT2A and 04025A220JAT2A:

Image(motorola_filter_replacement_step_6_low.jpg, 250px)
Image(motorola_filter_replacement_step_7_low.jpg, 250px)

=== Credits ===

Thanks to [ Sylvain] and Peter who made this possible.

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