MDS 05-3447A01, Rev. F
MDS 1710A/C and MDS 2710A/C/D
37
NOTE:
It is very important to use attenuation between all units in the
test setup. The amount of attenuation required will depend on
the number of units being tested and the desired signal strength
(RSSI) at each transceiver during the test. In no case should a
signal greater than –50 dBm be applied to any transceiver in
the test setup.
Invisible place holder
Figure 14. Typical setup for bench testing of radios
7.4 Helical Filter Adjustment
If the operating frequency of the radio is changed significantly, the
helical filters should be adjusted for maximum received signal strength
(RSSI). To adjust the filters, proceed as follows:
1. Remove the top cover from the transceiver by loosening the four
screws and lifting straight up.
2. Locate the helical filters on the PC board. See
Figure 15
.
3. Apply a steady signal to the radio at the programmed receive fre-
quency (–80 dBm level recommended; no stronger than –60 dBm).
This can be done with a signal generator or an over-the-air signal.
4. Measure the radio’s RSSI using one of the following methods:
• With an HHT (See
Section 5.0, TRANSCEIVER PROGRAM-
MING
on page 17).
• With MDS Radio Configuration Software (See
Section 7.5,
Upgrading the Radio’s Software
on page 38).
• With a voltmeter connected to Pin 21 of the
DATA INTERFACE
connector (See
Section 4.2, RSSI Measurement
on page 16).
A
N
T
E
N
N
A
1
3
.8
V
D
C
+
–
A
N
T
E
N
N
A
1
3
.8
VDC
+
–
A
N
T
E
N
N
A
1
3
.
8
VDC
+
–
A
N
T
E
N
N
A
1
3
.
8
V
D
C
+
–
POWER ATTENUATORS
• Fixed or adjustable
• 5W Minimum Rating
POWER DIVIDER
NON-RADIATING ATTENUATOR
• Install on any unused divider ports
• 5W Minimum Rating
COMPUTER RUNNING MDS
"POLL.EXE" PROGRAM
RTU SIMULATORS
MDS P/N 03-2512A01*
MASTER STATION
REMOTE
REMOTE
REMOTE
REMOTE
* Transceiver's internal RTU Simulator may be used if
external simulator is unavailable. See text.
