Main characteristics:
1) Case: aluminum alloy die-casting, high anti-violent, able to
glisten, convenient for looking for (optional).
2) Door cover: orient automatically and good self-closing, convenient
for use.
3) Handset: made of special engineering plastic, high anti-knock
resistance, high tensile strength resistance and high
anti-violent.
4) All of the components including handset telephone receiver and
transmitter, keypad, buzzer, circuit board and cabinet are
designed to be multi-layer waterproof and dust-proof that is up
to Class III grade.
5) Phone is provided with high stability, high anti-jamming
capability, and it is up to national standard GB/T 15279-94.

Main technical indexes:
1) Applicable for various types of SPC exchange and dispatching
exchange system with feeding voltage of 48-60V
2) Ambient temperature: -30oC~60oC
3) Relative humidity: 10%~95%
4) Atmospheric pressure: 86~106Kpa
5) Circumstance noise: ≤ 60dB (A)
6) Sound level of ringing: ≥70dB (A)
7) Standard frequency:
a) Low frequency group: 697, 770, 852, 941Hz
b) High frequency group: 1209, 1336, 1477Hz
c) Frequency deviation: ≤1.5%
8) If service line is a 3km signal level:
a) Standard frequency:
i) Low frequency group: -9dB3dB
ii) High frequency group: -7dB3dB
9) Level difference between low and high frequency of compound
signal: 21dB
10) The total distortion caused by intermediation of harmonic wave
is lower than the basic level by at least 20dB
11) Call transmission index: (5km) SLR≤12, RLR≤-1, STMR≥10
12) Output impedance is 600Ω
13) Super strong function is available for dialing 12 groups of
numbers stored in the memory (maximum length of each number
is 16 digits)

Specifications:
1) Defend grade: GB 4208-93 IP 66
2) Call capability of phone: GB/T 15279-94
3) Application scope: metro, light railroad, speedway, ship, mine
4) External configuration specification:
a) External dimensions: 320 x 205 x 120mm
b) Weight: 5.5kg
c) Installation dimensions:139 x 260mm
d) M8 bolt is used to install