User manual SENNHEISER SZI 1029

[. . . ] coverage area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 m2 Threshold voltage for automatic on/off function . . . . . . . . . . . . . . . . . . . 50 mV (RF signal) RF output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BNC socket Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx. [. . . ] The operational status of the diodes and the radiator is indicated by a green and a red LED at the front. If only the red LED is lit, the radiator is in stand-by mode and a mains voltage is present, but there is no RF carrier. If only the green LED is lit, the radiator is operating and transmitting an IR signal. The radiator switches on automatically as soon as it receives an RF signal of at least 50 mV. When the RF signal is no longer present, the radiator switches back to stand-by. If both the red and the green LED are lit, the radiator indicates a malfunction: more than four diode groups fail to operate. The radiator will continue to operate at a reduced radiating power but it should be repaired as soon as possible. The sockets and controls are on the base of the SZI 1029 (see diagram on the left). On each side, the radiator is fitted with a heat sink. When installing the radiator, care should be taken that these sinks are not covered and that the radiator is not mounted horizontally. The optimum position is vertical or almost vertical so that air can circulate freely through the cooling fins and heat is dissipated quickly. The modulator signal is fed to the BNC RF input. An automatic modulation control compensates for cable losses and ensures an optimum modulation level for the IR diodes. At the RF output socket (BNC) the signal can be daisy-chained to additional radiators. The mono/multi switch increases the radiating power by 3 dB when set to "mono". 50 % larger, but at the same time, the THD becomes greater, which would lead to interference with higher channels in multichannel operation. For this reason, you should only switch to "mono" for singlechannel applications and use the "multi" position for multi-channel operation. The SZI 1029 radiator has a 5/8" thread and is supplied with an adaptor for conversion to 3/8" or 1/2" threads. You will find suitable attachments such as mounting plates or table stands in the chapter "Accessories". The radiator's IEC mains connector can be secured by a steel clamp. The SZI 1029-24 variant is equipped with an XLR-4 connector as power supply socket. Green LED: operation indicator Red LED: stand-by Red and green LEDs: malfunction indicator LED indicators of the SZI 1029 MONO MULTI CHANNEL INPUT OUTPUT 1 1 2 3 4 5 6 7 234 5 6 7 1 Heat sinks RF input, BNC socket Mono/multi switch RF output, BNC socket Thread for mounting the radiator IEC mains connector Steel clamp for securing the mains connector Bottom view of the SZI 1029 with sockets and controls SZI 1029 IR Audio Transmission Technology | Modulators/Radiators MONO MULTI MONO MULTI CHANNEL INPUT OUTPUT INPUT CHANNEL OUTPUT Daisy-chaining the SZI 1029 When planning and installing an IR system you have to pay attention to use the correct terminating impedance for the radiator chains. Sennheiser IR modulators have an output impedance of approx. [. . . ] You can see that the signalto-noise ratio decreases the further you go away from the radiator. Eventually, the noise becomes so loud in relation to the useful signal that the squelch in the IR receiver mutes the audio output. A signal-to-noise ratio of 26 dB (the outer characteristic in the polar diagrams) gives an intelligible but noisy signal. A signal-to-noise ratio of > 40 dB, on the other hand, ensures a clear audio signal without the annoying noise. [. . . ]