12
SR–20C MONOPHONIC OPERATION CONNECTIONS
Refer to Figure 3 as required for the following connections.
1.
Connect the receiving antenna coax to the ANTENNA TYPE N port on the rear–panel using a type–N male
connector. A short flexible jumper, 20 inches maximum, may be used between the ANTENNA port and the
Heliax. Marti Part No. 585–017 Double–Shielded, Low–Loss RG–214/U jumper is recommended.
2.
Balanced program audio output is located at accessory circuit board connector J2–1 and J2–2 (refer to Figure 2).
The output level can be adjusted from –10 to +11 dBm. Connect shielded audio cable to J2–1 and J2–2. If
unbalanced audio is desired, connect a cable to BNC receptacle J2 on the rear panel.
3.
Connect a remote control or subcarrier demodulator to the jack marked, “J1”. The subcarrier load may be 600
to 5K ohms impedance, and the output level is approximately 0.5 Volts peak–to–peak. Systems factory supplied
with 250 KHz IF bandwidth will carry subcarriers up to 110 KHz. For other subcarrier frequencies or narrow IF
bandwidth systems contact the factory. A second subcarrier system can be connected to “J3”. Subcarrier
frequencies may be between 26 KHz and 110 KHz.
4.
For dual channel stereo operation, use only Marti MTS–1 coaxial transformer for splitting the received signal to
the two receivers.
CAUTION
IF DC OPERATION IS REQUIRED, DO NOT APPLY MORE THAN +14V
TO THE UNIT.
5.
Ensure the receiver rear–panel ON/OFF switch is OFF. Connect the rear–panel AC line receptacle to an 85 to
264V, 47 to 63 Hz AC power source. USE ONLY A 3–PRONG GROUNDED OUTLET RECEPTACLE
FOR SAFETY. The unit can also be operated from a +10V to +14V external dc supply. If dc operation is
required, refer to Figure 2 and connect: 1) the positive wire to J2–13 and 2) ground to J2–14.
6.
The receiver is equipped with a rear–panel ground terminal. Connect a ground wire between earth ground and
the GND terminal on the receiver rear panel.
SR–20C COMPOSITE OPERATION CONNECTIONS
1.
Connect the receiving antenna coax to the ANTENNA TYPE N port on the rear–panel using a type–N male
connector. A short flexible jumper, 20 inches maximum, may be used between the ANTENNA port and the
Heliax. Marti Part No. 585–017 Double–Shielded, Low–Loss RG–214/U jumper is recommended.
2.
Balanced monophonic program audio output is located at accessory circuit board connector J2–1 and J2–2 (refer
to Figure 2). The output level can be adjusted from –10 to +11 dBm. Connect shielded audio cable to J2–1 and
J2–2. If unbalanced audio is desired, connect the cable between J2–1 (audio) and J2–3 (ground).
3.
The composite signal output of the receiver is located at J2 on the rear panel. The composite output is con-
nected to the composite signal input of the FM transmitter exciter by a short length of RG–58 coaxial cable.
Connect the cable between J2 COMPOSITE OUT and the composite input on the exciter.
4.
A subcarrier demodulator or remote control can be connected to the SUB 1 OUT J1 or SUB 2 OUT J3 BNC
receptacles on the rear panel. The ability of the STL transmitter system to transmit subcarriers depends upon the
channel bandwidth available. The SR–20C receiver IF filter selectivity must be compatible with the available
interference free channel bandwidth. The following text presents the approximate bandwidth required for
various sub carriers using 50 KHz deviation for 100% modulation.
Subcarrier Frequency
Receiver IF Bandwidth (3 dB)
67 KHz
234 KHz
92 KHz
284 KHz
110 KHz
320 KHz
Содержание SR-20C
Страница 1: ...MARTI ELECTRONICS STL RECEIVER MODELS SR 20M SR 20C October 2003 IM No 597 8105...
Страница 15: ...10 FIGURE 1 SINGLE DUAL SR 20M SYSTEM 597 8105 1 COPYRIGHT 2003 MARTI ELECTRONICS INC...
Страница 16: ...11 FIGURE 2 ACCESSORY REMOTE CONNECTIONS 597 8105 2 COPYRIGHT 2003 MARTI ELECTRONICS INC...
Страница 18: ...13 FIGURE 3 SR 20C SYSTEM DIAGRAM 597 8105 8 COPYRIGHT 2003 MARTI ELECTRONICS INC...
