R&S ZVA8, Service Manual

Page: 320 / 606

Repairs R&S ZVA
1177.5333.02 3.12 E-11
Doubler67
The doubler contains a frequency doubler for the range 40 GHz to 70 GHz, a switchable filter unit and a
broadband amplifier for the range 10 MHz to 70 GHz.
Range Frequency range from
driver42
Doubler Output frequency
1 10 MHz to 41.6 GHz --- 10 MHz to 41.6 GHz
2 20.8 GHz to 27.0 GHz x 41.6 GHz to 54.0 GHz
3 27.0 GHz to 35.0 GHz x 54.0 GHz to 70.0 GHz
Receiver67
The receiver section has two channels (measurement channel and reference channel). The
measurement channel contains a buffer amplifier, two mixers for each of the frequency ranges 10 MHz
to 2.5 GHz and 2.5 GHz to 70 GHz, LO doublers, LO amplifiers and an IF amplifier. The reference
channel is identical to the measurement channel without the buffer amplifier. In the mixers, the input
signal is directly converted to the IF signal 17.5 MHz. In the frequency range 10 MHz to 24 GHz the
mixers are used as basic wave mixers (IF = LO
– RF). In the range 24 GHz to 70 GHz the mixer for the
upper frequency range works as a harmonic mixer (IF = 3LO
– RF).
The LO signal section contains a frequency doubler for the range 12 GHz to 24 GHz, a switchable filter
unit, an adjustable attenuator and a broadband amplifier for the frequency range 30 MHz to 24 GHz.
Range Basic frequency range
from synthesizer
Doubler Output frequency
1 30 MHz to 12.0 GHz --- 30 MHz to 12.0 GHz
2 6 GHz to 8.15 GHz x 12.0 GHz to 16.3 GHz
3 8.15 GHz to 12.0 GHz x 16.3 GHz to 24.0 GHz
Each of the reflectometers RM1 and RM2 contain two voltage-controlled fans to perform optimum
cooling.
Diplexer80
Combiner Unit
In the Combiner Unit the generator signals from the Base Unit (10 MHz to 50 GHz) and from the
Reflectometer Unit (50 GHz to 80 GHz) are combined and the reflected or transmitted signals from the
DUT are splitted to a Coupler for the frequency range 10 MHz to 50 GHz and to the Converter Unit
(frequency range 50 GHz to 80 GHz). The Coupler separates the signal going to the DUT (Ref) from the
signal coming from the DUT (Meas). This two signals are directly fed to the Base Unit (port1 or port2).
Switch
The generator signal coming from the Base Unit is switched to the Coupler (frequency range 10 MHz to
50 GHz) or to the Converter Unit (frequency range 50 GHz to 80 GHz).