R&S ZVA24, Service Manual

Page: 319 / 606

R&S ZVA Repairs
1177.5333.02 3.11 E-11
The LO signal section contains a frequency doubler for the range 8 GHz to 16 GHz, a switchable filter
unit, a second frequency doubler with filter for the range 16 GHz to 24 GHz and a broadband amplifier
for the frequency range 30 MHz to 24 GHz.
Range Basic frequency range
from synthesizer
Doubler 1 Frequency Doubler 2 Output frequency
1 30 MHz to 8.0 GHz --- 30 MHz to 8.0 GHz --- 30 MHz to 8.0 GHz
2 4 GHz to 8.0 GHz x 8.0 GHz to 16.0 GHz --- 8.0 GHz to 16.0 GHz
3 4.0 GHz to 6.0 GHz x 8.0 GHz to 12.0 GHz --- 16.0 GHz to 24.0 GHz
Each of the reflectometers RM1 and RM2 contain two voltage-controlled fans to perform optimum
cooling.
Reflectometer Unit ZVA67
A reflectometer unit comprising a
coupler , a generator section (Driver42 and Doubler67) and a
receiver section (Receiver67) is incorporated in every port (Port1 to 4). The generator and the
receiver are screwed together to form a compact unit.
Coupler Unit
The coupler contains a bias-T and two directional couplers. One coupler is used to separate the signal
going to the DUT from the signal coming from the DUT. The reference signal (= measure of the signal
to the DUT) is obtained from the second coupler. The reference signal provides a reference for relative
measurements.
Driver42
The driver contains a frequency doubler for the range 12 GHz to 24 GHz with a switchable filter unit and
a second frequency doubler with a switchable filter unit for the range 24 GHz to 42 GHz. Switchable
amplifiers and attenuators and two adjustable attenuators are used to keep the output level constant
and to attenuate it electronically.
Range Basic frequency range
from synthesizer
Doubler 1 Frequency Doubler 2 Output frequency
1 10 MHz to 12.0 GHz --- 10 MHz to 12.0 GHz --- 10 MHz to 12.0 GHz
2 6.0 GHz to 6.75 GHz x 12.0 GHz to 13.5 GHz --- 12.0 GHz to 13.5 GHz
3 6.75 GHz to 9.0 GHz x 13.5 GHz to 18.0 GHz --- 13.5 GHz to 18.0 GHz
4 9.0 GHz to 12.0 GHz x 18.0 GHz to 24.0 GHz --- 18.0 GHz to 24.0 GHz
5 6.0 GHz to 6.75 GHz x 12.0 GHz to 13.5 GHz x 24.0 GHz to 27.0 GHz
6 6.75 GHz to 9.0 GHz x 13.5 GHz to 18.0 GHz x 27.0 GHz to 36.0 GHz
7 9.0 GHz to 10.5 GHz x 18.0 GHz to 21.0 GHz x 36.0 GHz to 42.0 GHz