8
TS42DLX Deluxe Test Set
Users Guide
Operation
The test set has two basic modes of operation: Talk
mode and Monitor mode. Talk mode is used for off-
hook operations (such as dialing verification, automatic
number identification, and audio quality verification).
Monitor mode is for audio monitoring of the Tip and
Ring pair while on-hook. In Monitor mode, the test set
has a high input impedance, which allows monitoring
of the line without disrupting conversations or data
signaling if present.
W
Caution
When testing circuits that are close to a
battery source, clipping onto a line may case
loud pops in the receiver. Holding the
receiver tightly against your ear may cause
acoustic shock. The test set is designed to
rest comfortably on the shoulder with some
space between the receiver and the ear. It
should be used in this position when
working close to a battery source.
Shorting the Tip and Ring leads together
while connected to a data line will disrupt
data on the line.
Talk/Monitor Switch
The TALK/MONITOR switch is a rocker switch located
on the side of the test set. The T position puts the test
set into Talk mode. The M position puts the test set into
Monitor mode.
Using the Test Set in Monitor Mode
While in Monitor mode, the test set is always on-hook.
The test set draws no direct current from the line and it
transmits no signals to the line. In this mode, the test
set has a high AC input impedance, which allows
listening for audio signals without disrupting
conversations or data signaling that might exist on the
line.
HI/LO VDC
(high/low Vdc)
LEDs
When the test set is on-hook and the TEST key is pressed, the unit measures the DC voltage
across Tip and Ring and indicates the voltage level as follows:
Voltage Range Indication
0 V to 2 V
LO Vdc LED lights for 5 seconds
2 V to 42 V
LO Vdc LED blinks for 5 seconds
42 V to 53 V (Normal CO battery voltage)
Both the LO Vdc and HI Vdc LEDs flash once
53 V to 140 V
HI Vdc LED blinks for 5 seconds
Above 140 V
HI Vdc LED lights for 5 seconds
If the indicated voltage causes either LED to light solidly for 5 seconds, the voltage has been
measured at a level which the test set will not allow off-hook operation.
If the test set is placed in Talk mode on a loop with more than 140 Vdc, the test set will lock out
and the HI Vdc LED will remain lit until the test set is placed in Monitor mode or the voltage
drops below 140 V.
Table 2. Test Set Keypad Control and Indicators (continued)
Key or Indicator
Description (see Figure 3)
