Ecler ATA1-1R - Manual (Page 4)

4
1. IMPORTANT REMARK
Congratulations! You are the owner of a carefully designed and manufactured equipment. We
thank you for having purchased our ATA1-1R telephone adapter.
It is VERY IMPORTANT that you read this manual before connecting the amplifier in order to
obtain its maximum performance.
We recommend our authorised Technical Services whenever any maintenance task should be
needed so that optimum operation shall be achieved.
1.1. Safety Precautions
This apparatus must be earthed through its mains cable.
Do not expose the unit to rain or water splashes, and do not place liquid containers or
incandescent objects like candles on top of the unit.
Should any connection / disconnection task be done, always disconnect the unit from the mains
supply.
There are no user serviceable parts inside the unit.
2. INTRODUCTION
The conventional telephone line, due to economic reasons, only provides two cables and obviously
does not support two separate signal ways, e.g. from a transmitter to a listener and from the listener to the
transmitter. In fact, those two signals would be mixed and could not be separated from each other. If we
would connect a telephone line directly to the input of an audio mixer, to pick up the voice of a listener who
calls by phone, the high fidelity signal sent to the line to answer (e.g. the speaker's voice from a radio
program) would also appear on the mixer's input, mixed with the listener's voice and with reduced
bandwidth due to the telephone line's bandwidth (300-3000Hz). Since the telephone signal has to be added
afterwards to the speaker's mic signal using the mixer, to obtain the global program signal, there will be
"two added speaker voices", the original one, with high quality, and the other one that appears inevitably on
the telephone line, with reduced bandwidth. The result, possible positive feedback (coupling) and changes
on the speaker's voice, reinforced between 300 and 3000Hz and therefore characterized by an appreciable
nasality.
The telephone adapter is a device that, connected between the mixer and the telephone line, allows
receiving signals from the line and sending them to the mixer and returning signals from the mixer to the
line, but without returning the signal, necessarily, to the mixer again.