Telex ST-300 Operating Instructions

Preliminary Operating Instructions
Telex Model ST-300 Auditory Assistance Transmitter
Carefully unpack your Auditory Assistance Transmitter. If there is any damage or
shortages, please refer to the "Warranty Service Information".

Set-up Instructions:

Power: Power will be received from the supplied "wall cube". Before applying
power, it is suggested that all input cords be plugged in and the antenna be screwed
onto the transmitter. Insert the cord plug into the transmitter before plugging in the
wall cube. The wall cube normally supplied is for 120 V AC, 60 Hz use only.
Transmitter Location: Select a suitable location for the transmitter. Try to keep a
clear, unobstructed path between the transmitter and the receiver. The transmitter
should not be located near metallic objects such as building structures and file
cabinets. Locating the transmitter on top of a file cabinet is OK. Avoid high heat sources
such as radiators .
Antenna: The transmitter uses a special "reverse" RF connector on the model ST-300.
This is intentional and is designed to comply with FCC Part 15 Rules. The antenna
supplied should be the only antenna used with the ST-300. The antenna is designed to
operate in the vertical position.
Audio Input: One or both of the audio input connections can be used at the same time. A
single modulation limiter serves both inputs. If either input is not used, that input should
be "turned off". Unbalanced devices should be plugged into the ¼ in. (quarter inch)
Unbalanced Audio input jack located on the rear panel. Tip is "hot" and the barrel is
ground. Balanced devices should be plugged into the Balanced Audio "XLR" jack
located on the rear panel. Pin 1 is Common (or ground), Pin 2 is audio input, Pin 3 is
audio input. See operating instructions for additional information.
E.D.R. audio: The Telex ST-300 Transmitter is equipped with E.D.R., Enhanced
Dynamic Range (companded) audio. This mode greatly improves the Audio Signal
to Noise Ratio when the ST-400 is used with the Telex Model SR-400 receiver. The
E.D.R. mode must be selected on the transmitter and receiver to be effective. Also,
The E.D.R. Mode must be de-selected if the ST-300 is used with more economical
receivers such as the Telex SR-50 receiver. See Operating Instructions for further
information.