
Section 5: Options and Accessories
Page 5-4
8197 Instruction Manual
Crosstalk (Isolation): 80 dB minimum.
Output Phase Noise:
Typically less than -130 dB/Hz 1 kHz from carrier for
10 MHz input to base station amplifier.
Line Tap Size:
5.25 L x 2.63 W x 1.71 H inches. (133 L x 67 W x 43 H mm).
Mounting hole pattern: 4.75 x 1.75 inches (121 x 44 mm).
5.2.1.2
Model 8140VT VersaTap
TM
Frequency Synthesizer
The VersaTap
TM
is a single-frequency synthesizer whose output is factory-set to
any frequency between 1 kHz and 16 MHz in 1-kHz increments and up to 20
MHz in 2 kHz increments. Some special frequencies can be furnished, such as
the 3.5795454...MHz TV color sub-carrier. Exact frequencies must be specified
at time of order.
Input:
Buffered high impedance input. Accepts 10.0 MHz with signal level
between 100 millivolts and 5.5 V p-p on a DC voltage of 7 to 12 VDC. The DC
current requirement is 110 milliamps at +12 VDC.
Output A:
A sine wave of 600 mV rms at the specified frequency into a 50-ohm
load for frequencies greater than 60 kHz. A TTL output for frequencies below 60
kHz with a source impedance of 50 ohms (SN74S140) driver.
Output B:
A TTL output at the specified frequency with a source impedance of
50 ohms (SN75S140 driver). If the internal jumper, W6, is moved to location W5,
Output B is HIGH when the VersaTap
TM
is phase locked to the incoming
reference and LOW when it is unlocked.
Lock LED:
The LED will light when the VersaTap
TM
is locked to the incoming
reference. The LED will blink if the DC input is low, which may cause the
VersaTap
TM
to malfunction. The LED will be unlit when the VersaTap
TM
is not
locked to the incoming reference.
VersaTap
TM
Size:
8.3 L x 4.2 W x 1.7 H inches. (211 L x 107 W x 43 H mm).
Mounting hole pattern 8.88 x 2.75 inches (225.4 x 69.9 mm).
5.2.1.3
Model 8140TA Line Extender Amplifier
The Line Extender Amplifier must be used to boost the output signal when the
coaxial distribution network is more than 1500 feet (457 m) long. The Line
Extender will drive an additional 1500-feet (457 m) of RG58 coaxial cable with
Model 8140 Line Taps installed along its length.Two DC-isolated 50-ohm
terminators must be used: one at the input tee connector of the Line Extender
Amplifier and one at the far end of the cable connected to the output of the Line
Extender Amplifier.
See the “Typical Interconnection Diagram” at the end of this section for an
approved method of interconnection.