R&S ZVA24, Руководство по обслуживанию

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Repairs R&S ZVA
1177.5333.02 3.120 E-11
Receiver levels
The following is assumed:

The LO synthesizer section (synthesizer1 mod. 20, synthesizer2) associated with the reflectometer to
be tested is OK.

The network controller associated with the reflectometer to be tested is OK.

One reflectometer in the instrument is functioning.

Loosen cable W515 (coupler unit -> MEAS) and cable W518 (coupler unit -> REF) at both ends
and screw off at the MEAS and REF receiver inputs.

Connect the receiver input (MEAS or REF) to a functioning instrument port using an adapter cable.

Set the ZVA to the CW sweep mode.

Set the frequencies and output levels for the port used for the measurement as indicated in the
table and read off the level for the receiver to be tested (wave quantity ax or bx).
Frequency Output level Displayed level
ax or bx
10 MHz -30 dBm
+20 dBm

3 dB
100 MHz -30 dBm
+5 dBm

3 dB
1 GHz -20 dBm
-5 dBm

3 dB
2.5 GHz -20 dBm
-10 dBm

3 dB
3 GHz -20 dBm
-10 dBm

3 dB
8 GHz -20 dBm
-10 dBm

3 dB
9 GHz -20 dBm
-10 dBm

3 dB
12 GHz -20 dBm
-10 dBm

3 dB
15 GHz -20 dBm
-8 dBm

4 dB
18 GHz -20 dBm
-8 dBm

4 dB
20 GHz -20 dBm
-8 dBm

4 dB
With the stated levels, the cable loss must still be taken into account. For the specified cable, it is
0.25 dB/GHz (0.5 m) or. 0.5 dB/GHz (1 m).
If the measured values are more than 2 dB below the levels list in the table, the board must be
replaced.
Testing the Network Controller Board
Testing the IF inputs
It is assumed that there is one functioning reflectometer in the instrument.

Disconnect the IF-MEAS and IF-REF cable from each of the reflectometers.

Connect the input to be tested at the end of the appropriate IF cable (W136, W137, W138, W139,
and W146, W147, W148, W149) to a functioning port using the adapter cable and SMA-N adapter .

Set the ZVA to CW sweep mode, CENTER 17.512345 MHz.

Setting at the port used for the measurement: POWER -10 dBm

Setting at the port associated with the network controller under test: WAVE QUANTITY ax or bx.