Hubbel RFL PLC Hybrid Pro, Руководство пользователя

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RF-MCHYBRIDPRO-01
Hubbell Power Systems, Inc. – RFL™ Products
June 2019 31 973.334.3100
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If performing in-circuit testing, with hybrids connected to each other, to
transmitters/receivers, and to the line tuner, always use the meter’s high-impedance
input
•
When using the high-impedance input on an FSVM, a “reference impedance” must be set so
that the meter can accurately calculate power levels. Verify that the reference impedance is
set to the operating impedance of the hybrid (typically 50 ohms)
F
IGURE
37 shows an example of how ports might be terminated for a balanced hybrid bench test:
•
TX1 is terminated by the signal generator’s source impedance setting
•
TX2 is terminated by a dummy load
•
OUT is terminated by the meter’s 50-ohm input
TX1
TX2
BAL
OUT
50-ohm
dummy load
To FSVM
50-ohm input
50-ohm source
impedance
Figure 37 – Example Terminations, Balanced Hybrid, Insertion Loss Test, TX1 to OUT
F
IGURE
38 shows an example of how ports might be terminated for a skewed hybrid bench test:
•
TX is terminated by a dummy load
•
LINE is terminated by the signal generator’s source impedance setting
•
RX is terminated internally on the hybrid; no external termination is needed
TX
RX
SK
LINE
To FSVM
high-impedance input
50-ohm
dummy load
50-ohm source
impedance
Hybrid port internally
terminated (J4 = IN)
Figure 38 – Example Terminations, Skewed Hybrid, Insertion Loss Test, LINE to RX