DRAKE HCP2550A Manuale di istruzioni - Pagina 5

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HCP2550A CHANNEL PROCESSOR
EAS
READY
POWER
The R.L. Drake HCP2550A is a high quality, frequency
agile channel processor capable of converting any VHF,
UHF, or CATV input signal to any standard output channel
between 54 and 550 MHz. Input and output frequency
are easily set with front panel pushwheel switches.
Selectable preamp and AFC provide stable reception of
weak or out-of-tolerance signals. A/V ratio and output
level controls are also provided along with IF loop-thru
connections to offer exceptional flexibility.
The synthesized input tuning permits reception of Off-Air
TV channels 2 through 69, standard CATV channels
2 through 125, and IRC, HRC channels 1 through 125.
A selectable preamp ensures reliable reception of weak
input signals. Selectable AFC ensures that out-of-
tolerance cable channels, VCR modulators, or UHF
translator signals will not affect the IF or RF output
frequencies of the HCP2550A. A front panel indicator
lights for signals that are within the AFC lock range.
A selectable and adjustable threshold level control for the
input signal level is also provided. An internally generated
carrier is substituted for input signals below the set
threshold level. A front panel signal indicator lights for
input signal strengths greater than a threshold value.
The use of SAW filtering permits reliable adjacent channel
operation of multiple Channel Processor and modulator
units. IF loop-thru capability in the HCP2550A supplies a
padded IF output prior to channel conversion.
This feature provides the capability to replace the
standard internally generated IF output with an alternate
source of composite IF, or allows the insertion of IF
scrambling equipment.
Introduction - Description
RF INPUT
+
CATV
100
IRC
PRE-AMP
AFC
CATV
HRC
4
OFF
STD
AIR
OFF
ON
OFF
ON
INPUT
CHANNEL PLAN
CHANNEL
RF OUTPUT
PILOT
A / V
THRESHOLD
RATIO
4
LOCK
DETECT
SIGNAL
The synthesized RF output can be set for any CATV
channel 2 through 78 and 95 through 99. FCC required
channel frequency offsets are automatically provided.
Offsets of ± and zero can be selected with a rear panel
switch. RF output level is front panel adjustable to
+60 dBmV maximum.
The output modulator section of the HCP2550A accepts
Emergency Alert System (EAS) signals as required by the
FCC Part 11 for many CATV systems. Either automatic or
manual activation of the Emergency Alert System input is
controlled by the rear panel (EAS) switch.
Coaxial connectors are provided for the RF Input, the IF
Loop-out and Loop-in, and the RF Output. All of the
above mentioned features, combined with a carefully
designed low intermodulation output stage, provide
reliable operation in a densely crowded SMATV or cable
environment.
1
OUTPUT
LEVEL
7
8
OUTPUT
ENABLED
OUTPUT
CHANNEL