The product can be used as the voice communication terminal or the double tone number-dialing terminal when the product is matched with the communication equipment. The product has the advantages of the high reliability and the stable performance. The moving-coil type m have the characteristics of the clear voice and the small distortion. The product has adopted the voice transmitting circuit and the dual tone multi-frequency number dialing pre-amplifying circuit so that the output signal intensity of the product has been enhanced.

Main specifications:

Operating temperature:－40℃～55℃

Dimension：202mm×80mm×64mm

Weight：(430±30)g

Frequency range：200Hz～4000Hz

Operating voltage：(12±3)V

Operating current：≤30mA

see table 1 for Frequencies combination of DTMF signal.

LFs(Hz)	HFs(Hz)
	1209	1336	1447
697	1	2	3
770	4	5	6
852	7	8	9
941	*	0	#

Level of DTMF signal:

Level of LFs:(－24±3)dBm

Level of HFs:(－22±3)dBm

The quantity level of HFs is（2±1）dB higher than that of LFs.

The deviation of single frequency among DTMF signal should be

within the range of ±1.5% of rated frequency.