User's Manual

10 Tuning the Receiver Front End © Tait Electronics Limited 2005
6. Adjust the receiver VCO trimmer until the actual band matches the desired
band. The bands turn green. Click Finish. This stores the lock band in the
reciter. The icon
on the Frequency Setup tab indicates that this task is
complete. Proceed to tune the front end.
Tuning the Receiver Front End
The second step in tuning the reciter frequency is to tune the receiver front
end. Tuning aims to maximise the receiver’s sensitivity and to flatten its
response across the lock band (switching range).
To help you do this, there is a graph of the RSSI readings in step two of the
Tune Receiver Front End Wizard. A number of RSSI readings are measured
across the switching range. These readings are then continually averaged to
produce the graph.
You should aim to achieve a response that looks something like this:
On UHF, 800 MHz, and 900 MHz reciters, you adjust helical filters. On VHF
reciters, you adjust trimmer capacitors.
Equipment ■ Tuning tool
■ CTU
Setup
6
4
3
1
2
5
1 PC 2 RS-232 cable 3 Programming port
4 CTU 5 Noise source 6 Reciter