User's Manual

tri2525b_ml_03_sd Approved: G.V. 16
Vecima Networks Inc.
3.0 ALIGNING THE ANTENNA
3.1 Preparation for Tuning
Before tuning the antenna insure that the cable modem is not connected to the power inserter. The
cable modem signal will prevent the signal strength indicator from responding to very weak receive
signals.
3.2 Signal Strength and Alignment
The TRI2525B is equipped with an audible alignment aid that simplifies the setup process. It permits
alignment to the hub site without the use of the cable modem or any test equipment.
The aid consists of a level detector for the full receive band, and a beeper sealed into the unit that
sounds at a rate that increases with increasing level. The beeper is activated only for about 3 to 10
minutes each time power is applied to the TRI2525B.
To use the aid, first mount the TRI2525B. If the unit is difficult to tilt or turn, loosen the locknuts on the
V-bolts slightly. Apply power to the TRI2525B when you are ready to begin. The beeper will start
sounding. Point the TRI2525B in the general direction of the hub site, then move it to maximize the rate
of the beeper. The highest rate heard represents the highest receive signal level and the best
alignment. Once the antenna alignment is complete, tighten the locknuts to secure the TRI2525B to the
pole. The beeper will automatically mute between 3 and 10 minutes after the unit was powered up,
turning off faster with higher received signal level.
The detector operates over a wide level range. Installations that are closer to the hub site and
consequently receive a larger signal will have a higher beep rate than an installation further out. In each
case, finding the alignment with the highest beep rate indicates the best alignment.
Note that the TRI2525B alignment aid does not discriminate between signals in the receive band. If
signals other than those from the hub are present, this could result in a misalignment. In this case, a
conventional alignment technique would need to be employed.
3.3 Resetting the Beeper
To reset the timer for alignment, simply unplug the power supply from its AC connection. Wait 5
seconds, and then plug the power supply back into its AC connection. The beeper will begin beeping as
soon as power is available.