
Troubleshooting R&S
ZVB
1145.1078.82 3.64
E-1
Bridge Directivity
The following is assumed:
•
The generator and receiver sections of the reflectometer associated with the bridge unit are OK.
¾
Screw the SHORT from an N calibration kit to the port connector.
¾
Perform a sweep from 300 kHz to 8 GHz, measure S11, save measured values (Data -> Mem :
Math = Data/Mem).
¾
Screw the MATCH from the N calibration kit to the port connector.
¾
The trace gives the directivity.
Frequency range
Directivity
300 kHz to 50 MHz
< -10 dB
50 MHz to 8 GHz
< -16 dB
If the measured values are greater than the values stated in the table, the bridge unit must be replaced.
Bridge unit: Port Matching
It is assumed that there is a functioning reflectometer in the instrument.
¾
Loosen cables W514 (GEN -> Bridge unit), W515 (Bridge unit -> MEAS) and W518 (Bridge unit ->
REF) at both ends and unscrew at the bridge unit.
N.B.:
When loosening, support the cable with a 7mm spanner
¾
Terminate the bridge unit input and bridge unit outputs with 3 SMA terminations.
¾
Connect N test cable to a functioning instrument port and perform a 1-port calibration at the end of
the cable.
¾
Connect the end of the test cable to the port of the bridge unit under test and display the Sxx
magnitude on the screen.
Frequency range
Sxx dB
300 kHz to 2 GHz
-12 dB
2 GHz to 8 GHz
-18 dB
If the values in the table are exceeded, the board must be replaced.
Summary of Contents for ZVB 4
Page 57: ...Instrument Construction and Function Description R S ZVB 1145 1078 82 I 3 2 E 1 ...
Page 133: ...1145 1078 82 5 5 E 1 Spare Parts List Mechanical Drawings ...
Page 142: ...1145 1078 82 5 15 E 1 Block Circuit Diagram ...
Page 143: ......
Page 144: ......
Page 145: ......
Page 146: ......
Page 148: ......
Page 149: ......
Page 150: ......
Page 151: ......
Page 152: ......
Page 153: ...1145 1078 82 5 17 E 1 Circuit diagrams ...
Page 154: ......
Page 155: ......
Page 156: ......