Telex Audiocom US-2002, User Instructions

28

Sidetone Adjustment

The US-2002 uses full-duplex audio, the same as a conventional telephone line, in which the talk and listen audio are sent and 
received on the same line. Thus, when you talk on a channel, you also hear your own voice back in the speaker or headphones. 
This is called sidetone. 

If you are using the US-2002 with a microphone and speaker, sidetone could cause unwanted feedback, since the microphone 
may pick up your returned voice audio and re-amplify it. This could also happen if you are using a headset where the ear 
cushions do not completely cover the ears. In either case, you should minimize the amount of sidetone. 

NOTE:

If you are using headphone that completely enclose the ears, you may want a certain amount of your own voice 

level heard to overcome the muffled sensation when talking.

To 

adjust sidetone using a speaker and microphone, or open-ear style headphones

, do the following:

1.

Simultaneously press the 

ALL Talk

 and

 PA 

keys to activate the test tone.

2.

Tap the 

channel 1 call key

 to send the test tone on channel 1.

3.

If you are using a headset, adjust the 

volume control

 at the US-2002 until you hear the test tone. 

OR
If you are using a speaker, adjust the 

volume control

 at the speaker.

4.

Using a small flathead screwdriver, adjust the

 channel 1 sidetone

 through the access hole in the bottom of the

US-2002 (Figure 16 on page 28) to minimize the tone volume.

5.

Tap the 

channel 1 call key

 to turn off the test tone on channel 1 when finished.

6.

Tap the 

channel 2 call key

, and repeat the steps 3 - 5 for the channel 2 sidetone.

7.

Tap any 

other key

, except a call key, to turn off the test tone when finished.

To 

adjust sidetone using headphones that completely enclose the ears

, do the following:

1.

Tap the 

Headset key

 to turn the headset microphone on.

2.

Tap the

 channel 1 Talk key 

to turn it on.

3.

While speaking into the microphone, use a small flat-bladed screwdriver to 

adjust the channel 1 sidetone

 so you 

hear your voice at an acceptable level in the headphones.

4.

Tap the 

channel 1 Talk key

 to turn it off when finished.

5.

Tap the 

channel 2 Talk key 

to turn it on, and adjust the channel 2 sidetone as for channel 1.

6.

Tap the 

channel 2 Talk key

 to turn it off when finished.

FIGURE 16.

US-2002 Bottom View