4-1
SECTION 4 OPERATION - HOW TO USE THE 3HRV HEADEND
REVERSE SWEEP RECEIVER
4.1 INTRODUCTION
This section provides detailed operation of the 3HRV. Included are
detailed descriptions of the various displays of the selected modes of
operation.
4.1.1 Wavetek Stealth Reverse Sweep Concept
With the reverse sweep option, a transmitter is built into the hand-
held sweep receiver. The headend reverse sweep receiver (3HRV) is
set up to receive the reverse sweep sent from the field. When a
reverse sweep is activated from a field test point, the 3HRV receives
the telemetry signal that indicates which receiver is sending the
sweep. The headend receiver measures the sweep, and sends the
results, along with the serial number of the sending receiver via its
telemetry signal to the field. The field receiver with the tagged serial
number then displays the sweep response as measured in the headend
on its LCD. Up to 10 receivers at a time can perform reverse sweep-
ing. If additional receivers attempt to sweep a message is displayed.
4.1.2 Basic Reverse Sweep Procedure
Sweeping the reverse path is a little different from sweeping the
forward path. Because the system is designed with appropriate spacing
for the forward high frequency range, the reverse path may not require
amplification at each station. The lower frequencies aren't attenuated
in cable as much as the higher frequencies. In sweeping the forward
path the amplifier is aligned such that its output is within certain
limits (the amplifier compensates for the cable behind it). However in
sweeping the reverse path the amplifier is aligned such that the
response at the headend is within certain limits
from this amplifier
alignment point
. So, in the reverse path the amplifier compensates for
loss characteristics in the cable in front of it.
Summary of Contents for 3HRV
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