Sennheiser SI 29-5 User Manual

SI 29-5

IR Audio Transmission Technology | Modulators/Radiators

Features

Modulator with up to five narrow-band audio channels

Each audio channel can be programmed to any of the 32 carrier frequencies

Several units can be cascaded to make systems of up to 32 channels

Integrated IR monitoring diodes

19“ (1 U) housing

Delivery includes: 1 x SI 29-5 modulator

General Description

The SI 29-5 is a 5-channel modulator. Its audio channels can be programmed to any

of the 32 narrow-band channels, and monitoring is no problem due to integrated IR

transmission diodes. The modulator is easy to program and features clear LED dis-

plays for monitoring all modulator functions.

Tec hnic al Da t a

Modulation .................................................narrow-band FM

Nominal/peak deviation...........................± 6 kHz/± 7 kHz

Amplitude limitation..... limiting amplifier (max. 30 dB)

Deviation display .................peak/5 dB/3 dB/ 1 dB/0 dB/

–1 dB/–3 dB/–5 dB/–7 dB/

–10 dB/–15 dB/–20 dB

Audio channels ..................................................................five

Channel frequencies .................................... 55 – 1,335 kHz

AF inputs I .........................................transformer-balanced

XLR-3F sockets, optional

12 V phantom powering

AF input II..................................... 25-pole sub-D socket, in

parallel with AF inputs I,

optional 12 V phantom powering

Input sensitivity................... 50 mV – 1.5 V (line) optional

0.5 mV – 30 mV (microphone)

AF frequency response................................50 – 12,000 Hz

THD ................................................................................< 0.5 %

AF signal-to-noise ratio................................. > 70 dB (A)

rms

RF outputs................................ 2 x BNC, short-circuit-proof

RF cascading sockets .................................................2 x BNC

Output impedance...........................................................50 Ω

Suppression of harmonics........................................ > 60 dB

Power supply ......... 12 V AC, via NT 29 plug-in mains unit

Power consumption .............................................max. 17 W

Dimensions .............................approx. 485 x 45 x 340 mm

Weight .................................................................approx. 4 kg

Cat. No. 003986

Recommended Accessories

Plug-in mains unit

NT 29 European version Cat. No. 004002

NT 29-120 USA version Cat. No. 004003

NT 29-UK UK version Cat. No. 004004

BNC-BNC co-axial cable

GZA 1019 A 1 (1 m) Cat. No. 002324

GZA 1019 A 5 (5 m) Cat. No. 002325

GZA 1019 A 10 (10 m) Cat. No. 002326

GZV 1019 A BNC coupler Cat. No. 002368

SI 29-5

Dimensions of the SI 29-5

485 mm

340 mm

45 mm

The SI 29-5 is a multi-channel modulator in a compact 19“ (1U) housing. Five audio

channels can be programmed to any of the 32 standardised narrow-band channels.

Using the cascading sockets at the back, up to seven SI 29-5 can be cascaded to

make a 32-channel system. The AF inputs at the back of the modulator are avail-

able twice. You have a choice of either feeding the audio signals to separate XLR-3F

sockets or to a 25-pole central sub-D connector for all inputs. Both input types are

connected in parallel and balanced by a transformer.

The modulator is programmed with the menu keys and the +/– buttons. By simul-

taneously pressing the INPUT key and either the + or – key, you can select the audio

channel to be transmitted. With CHANNEL, you can assign one of the 32 standard-

ised carrier frequencies to the selected audio channel. To avoid accidental repro-

gramming, you need to hold the CHANNEL key for about 1.5 seconds af ter you have

released the +/– but tons i n order to make the modulator accept the new carrier

frequency. Beside channels 0 – 31 you can also choose the “OF” (off) position, which

switches the audio channel off. The corresponding LED will go out. Switching of f

unused channels will increase your radiators’ output power as the number of chan-

nels reduces the radiator coverage area accordingly.

The AF LEVEL key serves to adjust the sensitivity of the corresponding audio input.

You can adjust line signals between 50 mV and 3 V in 50 steps. All modulator set-

tings are stored in an EEPROM. As a result, the data remain stored even if the modu-

lator has been disconnected from the mains for a long period of time. With the help

of the two IR monitoring diodes, you can listen to the RF signal with a suitable IR

receiver – even when the radiators have not yet been connected or do not cover the

technicians’ area.

You can connect two chains of IR radiators to the RF outputs of the SI 29-5. The BNC

sockets are short- circuit-proof. By means of the RF cascading sockets, the summing

signals of several SI 29-5 can be mixed. The two sockets are connected in parallel

and can be used both as an input and as an output.

For example, to set up a 15-channel system as shown in the drawing at the bottom

left, simply connect the modulators (no particular order necessary) with BNC-BNC

cables. The signal of all modulators will be available at any of the RF output sockets,

and you can operate the devices just as before. When setting up multi-channel

systems, you have to pay special attention not to assign a carrier frequency twice.

Even if one channel only transmits the carrier, the transmission of the modulated

signal on the other channel will be disturbed.

1 LED display for indicating the audio channel (1 – 5)

2 LED display for indicating the transmission

channel (0 – 31)

3 IR transmitting diodes for monitoring the RF

output signal

4 LED bargraph for deviation display

5 Menu keys

6 five LEDs for indicating the audio inputs which

deliver their signal to the RF output

7 +/– keys

1 2 3 4

5 6 7

SI 29-5 front panel

1 BNC RF cascading socket for connecting

additional SI 29-5

2 Five XLR-3F audio inputs, transformer balanced

3 BNC RF cascading socket for connecting

additional SI 29-5

4 BNC RF outputs to radiators, short-circuit-proof

5 Socket for plug-in mains unit, connector is twist-

locked to the socket

6 25-pole sub-D socket for all audio inputs,

in parallel with the XLR-3 inputs

1 2 3 4 56

SI 29-5 back panel

IR Audio Transmission Technology | Modulators/Radiators