Back Features
Insert RJ11 Connector
1 – Headset socket
Plugging in a headset will switch transmit/receive
(TALK mode) and receive (MON mode), from handset to
headset.
Note: For safety reasons use only headsets tested and
approved by Greenlee.
2 – Earpiece
Listen here in MON and TALK modes when not using
the headset.
3 – Mute
Press and hold for microphone mute in TALK mode.
4 – Volume control
TALK mode has three volumes: LOW/MED/HIGH. LOW
is similar to a normal phone's level. Acoustic shock
protection is provided in all settings.
5 – Microphone
Talk here in TALK mode when not using the headset.
6 – RJ11 lead socket
Pin 2: Ground; Pin 3: Tip; Pin 4: Ring
When Tip is positive with respect to Ring (normal
polarity), the green LED illuminates.
Lightning: To specification ITU K.17,20, 21 (1500 V).
Digital Services Protection (DSP)
OFF Mode
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Most PSTN and PABX analog telephone lines have a DC
feed of between 24 and 66 volts. The Digital Voltage
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alarm, a rapid beeping sound, warns you if you are
connected to a phone line which has more than 70 V DC.
If the alarm sounds, you have probably connected to a
line carrying a large DC voltage, to power some remote
digital equipment. In most cases this will be an ISDN
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NT or pair gain remote unit. Do not attempt to go off
hook but switch to monitor mode; you should hear the
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characteristic hiss of digital signaling. This will confirm
that the line is not analog but digital. Now you know
that extra care has to be taken with this line; breaking,
shorting, or connecting a normal telephone to this line
will result in disruption to the service.
High Voltage Off-hook Inhibit
If you attempt to go into TALK mode on a line that has a
DC feed of more than 110 V, the tester will not loop the
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line and you will hear longer warning beeps.
As well as protecting ISDN and pair gain services from
disruption, DSP protects the tester from damage due to
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it having to dissipate high power levels in TALK mode.
Field Repair
Field repairs are limited to replacing line cords (with
approved types) and replacing belt clips. Attempting
any other repair at field level is liable to damage the
instrument and will invalidate the manufacturer's
warranty. Check your company policy before considering
any repair. Although limited field repair may be possible,
your company may have a policy of centralized repair.
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