4. Manual Gain Adjustment ~ UL / DL
In order to meet and maintain safe environmental conditions for seamless
network integration, this repeater is equipped with a dip switch assembly that
allows you to manually control the Uplink / Downlink gain individually. The UL
/ DL attenuator control range is from 0dB to -31dB by 1dB increments in
each band. There is a dip switch bank available for each frequency.
Switches
1-5
on top & bottom respectively represent
DL
&
UL
adjustment for
LTE A+B
.
Switches
6-10
on top & bottom respectively represent
DL
&
UL
adjustment for
LTE C
.
4.1 Manual Gain Adjustment ~ UL / DL
–
Con’t.
When do you adjust the Repeater Gain?
This repeater is equipped with an alarm feature that monitors the input gain.
If the input gain is too high, the DL Alarm LED will change color from green
to either amber or red indicating the intensity of the error. High input gain can
occur if the donor antenna is in a location where the receive signal strength
(RSSI) from the cell tower is extremely good (-50dB or better) or if signal
oscillation is taking place. Signal Oscillation is when the amplified signal
from the indoor service antenna is being received back into the donor
antenna.
To determine the cause of your Alarm LED changing color, disconnect the
indoor antenna / service line from the “
INDOOR / OUTPUT
” port of the
repeater while the repeater is ON. If the LED does not change to green, then
your input signal from the cell tower is very strong. At this point you
attenuate the DL gain by 1dB increments till the LEDs turns green again.
Then you must match the same attenuation value to the UL set of switches.
If after reconnecting the indoor / output service line the LED changes back to
amber or red then signal oscillation is taking place. This is the result of your
Indoor / Service
and
Outdoor / Donor
antennas being too close to each
other and should therefore have more separation or continue to add more
attenuation.
When complete, try making some test calls throughout the desired area of
coverage while monitoring the LEDs to see if it changes color. If you are
showing strong signal strength but your calls are not going through, it could
be that you need to attenuate your uplink gain a bit more. Keep in mind
however that you do not want to have more than a 5dB difference between
the uplink and downlink values for optimum system performance.
We encourage you to call us if you are experiencing difficulty when
commissioning your repeater system. We want to make sure you have
seamless integration to the cellular network and optimal system
performance. We are always happy to help
. 1-866-4-JDTECK (53-8325).
13
Avoid putting more than a 5dB difference between the Uplink and Downlink.
14
Frequency Alarms
DL Switches ~ A+B
UL Switches ~ A+B
UL Switches ~ C
DL Switches ~ C
Note Switch Positions
Note Switch Positions
Example of the DL & UL
Attenuated by 4dB
