User Manual

Two Channel UHF Cell Enhancer
User Handbook
Handbook Number: 50-187601HBKM Page: 44 of 51
6.2 Downlink
Confirm that there is a signal at the expected frequency and strength from the base station. If this is
not present then the fault may lay outside the system. To confirm this, inject a downlink frequency
signal from a known source at the master site BTS input and check for output at the remote site
feeder output.
If a signal is not received at the output it will be necessary to follow the downlink path through the
system to find a point at which the signal is lost. The expected downlink output for the given input can
be found in the end-to-end test specification.
6.3 Uplink
Testing the uplink involves a similar procedure to the downlink except that the frequencies used are
those transmitted by the mobile equipment.
6.4 Fault repair
Once a faulty component has been identified, a decision must be made on the appropriate course to
carry out a repair. A competent engineer can quickly remedy typical faults such as faulty connections
or cables. The exceptions to this are cable assemblies connecting bandpass filter assemblies that are
manufactured to critical lengths to maintain a 50-ohm system. Care should be taken when replacing
cables or connectors to ensure that items are of the correct specification. The repair of component
modules such as amplifiers and bandpass filters will not usually be possible in the field, as they
frequently require specialist knowledge and test equipment to ensure correct operation. It is
recommended that items of this type are replaced with a spare unit and the faulty unit returned to AFL
for repair.