OSCOR OSC 5000 - Manually Sweeping Selected Inputs; Checking for Carrier Current Threats

SECTION 6: CONDUCTING A SWEEP
97 REI OSC-5000E
Manually Sweeping Selected Inputs
When performing a sweep, several inputs are easily searched using manual operation.
There are very few friendly signals that exist in some inputs, such as infrared, RF Loop, AC
VLF, and MDC. Rather than allowing the OSCOR to search these inputs, it is faster to
select these inputs in the Manual Sweep Mode, and manually tune to any signals for
verification.
NOTE: Be sure that no computer monitors are turned on when testing the RF Loop
antenna. The loop antenna will pick up and display several harmonic signals from a
video monitor. The Loop antenna may also pick up low frequency RF radiating from
fluorescent light ballast. You may need to try the Loop with the lights turned off using the
OSCOR backlit display.
Checking For Carrier Current Threats
Check every outlet for carrier currents using the AC VLF probe (the OSCOR power cord).
An extension cord is a useful tool for this procedure. Even within the same room,
electrical outlets may be on different circuits and may not transmit carrier current if the
building is large and the electrical circuits are transformer coupled. Each electrical outlet
should be taken apart for inspection. The OSCOR AC power cord can also be used to
test for carrier current signals on any pair of conductors less than 250 volts using the VLF
adapter probe in the OSCOR case. See page 9.
Before testing an unidentified pair of power conductors, a voltmeter should be used to
measure the voltage across the conductors. If this voltage exceeds 250 volts,
do not test
with the OSCOR. If the voltage exceeds 120V, switch the OSCOR power switch to 230V
to provide extra protection against over-voltage.
To test miscellaneous conductors for Carrier Current:
1. Be sure the conductor voltage does not exceed 250V using a voltmeter.
2. Place the OSCOR in the Sweep Mode with the AC VLF input displayed.
3. Press SHIFT then EXPAND to ensure that the maximum frequency window is
displayed.
4. Visually inspect the display for signals. Tune to any signals of interest and evaluate
the signals for threat potential.
WARNING: Exposing the AC VLF probe to an excessive voltage
(more than 450 volts DC) may cause damage to the power circuit.