Hubbel RFL PLC Hybrid Pro, Руководство пользователя

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RF-MCHYBRIDPRO-01
Hubbell Power Systems, Inc. – RFL™ Products
June 2019 19 973.334.3100
NOTE: If the current limiting resistor is used, the RX termination must be done on the skewed
hybrid. In other words, if J5 is set to “IN”, J4 must also be set to “IN”. If J5 is set to “OUT”, J4
can be either “IN” or “OUT”.
Table 4 – Skewed Hybrid Specifications
Skewed Hybrid Specifications
Operating Impedance (each port)
50 ohms (75 ohms available by request)
Insertion Loss (TX to LINE) approximately 0.5 dB
Insertion Loss (LINE to RX) approximately 13 dB
Isolation / Trans-hybrid loss (TX to RX) greater than 40 dB
Power Rating 10 Watts, each port
Second Harmonic Distortion At least 80 dB below the fundamental frequency
Third Order Intermodulation Products At least 60 dB below the fundamental frequency
4.3 Skewed Hybrid Front Panel Test Switch
F
IGURE
14 shows the functional circuit of the test switch on the skewed hybrid front panel. The switch
is most commonly used for taking reflected power measurements when the channel is in service. With
the switch in the NORM position, connections are made from HYB OUT to the input of the reflected
power measurement device (instrument), and from the output of the instrument to the TO TUNER port.
Once the connections have been made up and the instrument is ready to measure, the switch is placed
in the TEST position. This diverts the signal energy through the instrument and the measurement is
then recorded. After the measurement has been recorded, the switch is placed back in the NORM
position, and then the cables may be removed. Throughout this process, the power line carrier channel
is never out of service.