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3SRV
The Wavetek hand-held System Sweep Receiver performs essential
cable TV system preventive maintenance tests with accuracy and
ease. Signal levels, hum, C/N, and frequency response can be quickly
tested without subscriber interference.
The Sweep System is made up of two components; the 3SR Receiver,
and 3ST Transmitter. The contents of this manual will describe the
care and operation of the 3SR Receiver, including Reverse Sweep
option using the 3HRV Headend Reverse Sweep Receiver.
Frequency response is tested by injecting a low level signal in vacant
spectrum areas, and monitoring cable system carrier levels in occupied
spectrum areas. In addition to generating the sweep test signal, the
3ST Transmitter continuously monitors the system carriers. The 3ST
sends headend level readings to the 3SR Receiver with every sweep
update. In this way, any headend level changes are compensated by
the receiver to maintain the utmost measurement accuracy.
With the Reverse Sweep option, a transmitter is built into the handheld
sweep receiver. The headend sweep transmitter (3ST) is set up
to receive the reverse sweep sent from the field. When a reverse
sweep is activated from a field test point, the headend transmitter
receives the telemetry signal that indicates which receiver is sending
the sweep. The headend transmitter 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.
The addition of the 3HRV to the Wavetek Sweep System takes the
responsibility of the reverse sweep away from the 3ST. This serves to
speed up the reverse sweep rate. In addition, the 3HRV sends out
reverse ingress/noise information with every update of its forward
telemetry, so reverse telemetry need not be received in order to check
the reverse ingress condition. In addition, the 3HRV allows up to 10
users to sweep the reverse path simultaneously.
Highlights:
- Frequency
Range: 5 to 1,000 MHz
Accuracy: + 10 ppm at 25°C; + 10 ppm drift over
temp.; + 3 ppm/year aging
Resolution Bandwidths: 30, 280 kHz (30 kHz for CSO/CTB only)
Tuning Resolution: 10 kHz
Sweep Resolution: 250 kHz maximum
1.2.2 Level Measurement
Range: -40 to +60 dBmV
Resolution: 0.1 dB
Accuracy: + 1.0 dB from -20 to + 50°C (typical),
(relative to 25°C)
- Depth of Modulation
Assumes presence of white reference on any VITS line. Nonscrambled
channels only.
Range: 80 to 100%
Resolution: <0.5% at 85%
1.2.11 Serial Interface
Serial, RS232; Epson, IBM Printers
- General
Log Linearity: +0.5 dB (typical)
Flatness: +0.5 dB @ 25 °C, @ 20 dBmV
Dimensions: 15.2 cm (W) x 25.4 cm (H) x 5.1 cm (D), 6"
(W) x 10" (H) x 2" (D)
Weight: 1.95 kg (4.3 lbs.), w/Reverse Sweep Option
2.2 kg (4.9 lbs.)
- Powering
Battery Life: 2.5 hours continuous (absolute worst case),
replaceable battery cartridge; w/Reverse
Sweep Option 1.75 hours continuous
(absolute worst case)
Charge Time: 4 hours fast charge; 30 hours slow charge
(with unit operating)
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