Download Tests of STO IF Components S. Weinreb April 15, 2009

Tests of STO IF Components
S. Weinreb
April 15, 2009
• Two 1-2 GHz IF amplifier plates and one 5
GHz converter plate for the Texas test flight
have been assembled and tested.
• Components for six more IF amplifier strings
are on hand for the Antarctic flight.
STO IF Amplifier Plates
Test data on SN1 shows noise output power spectrum with input terminated
and DC supply at 5.0V (310mA) and 4.0V (300mA). Resolution 1 MHz, total
output power of -25.1 dBm, and monitor detector output of -1.83 mV.
Expected input signal of -60 dBm/GHz will raise these levels by 20 dB.
There are 10+6 dB pads between the two 38 dB IF amplifiers.
Test data on SN2 is almost identical with -25.3 dBm output power and
monitor detector output -1.98mV at 5.0V DC.
Test Setup for 5 GHz Converter
Rohde and Schwarz 4-port network analyzer is used to provide 6.5 GHz LO
and measure conversion gain shown on next slide. A 5 GHz bandpass filter
will be added at input by U. of Arizona.
STO 5 GHz Converter Plate, April 15, 2009
Test data shows conversion gain (~18 dB) with +7 dBm LO at 6.5 GHz and also
with 0 dBm LO power. RF input was 4 to 6 GHz giving 2.5 to 0.5 GHz IF out.
For -5 dBm output, -23 dBm input power is needed. There are 3 dB pads at RF
input and IF output of mixer.
Calibration Curve for Monitor Detector
At design IF output of -5 dBm detector output is -100mV.
Detector Voltage Out vs IF Power Out
100000.0
Vdet, mV
10000.0
Measured Det Out
Square Law
1000.0
100.0
10.0
1.0
0.1
-30 -25 -20 -15 -10
-5
Pout, dBm
0
5
10
15
Parts for Six More IF Amplifier Plates
• Amplifiers, power splitters, attenuator pads, and cables to be combined with
Lorch filters and packaged in a receiver box for the Antarctic flight. Some
additional cables and pads will be required.