Scale Power Measurement
Pengcheng JiaNov 21, 2002
System Setup
LabView Program
Power SupplyAgilent 3631
Power SupplyKEPCO
Signal SourceWiltron 68001
TWTA
Power MeterHP438A
Coupler #1
Power Sensor AAgilent 8485A
DUT
Coupler #2
Attenuator20dB / 100 Watt
Spectrum AnalyzerHP8563
Power Sensor BAgilent 8481B
GateBias
DrainBias
8 Channel Supplyfor 32 MMICs
Control Program
Calibration Procedure
Coupler #1
Power Sensor A
Power Sensor B
(a)
SMA to N Adapter
Coupler #1
Power Sensor A Power Sensor B
(b)
SMA to N Adapter
Attenuator 20dB / 100 Watt
Coupler #2
Spectrum Analyzer
Power Meter & Power Sensor
• Calibration of power meter (for 438A)
1. Press Zero
2. Connect power sensor to POWER REF port, press Cal Adj, enter the Ref CF number on your power sensor
3. Press Cal Factor, enter the CF number at your frequency
Note: When calibrate with high power sensor 8481B, remove the 30 dB attenuator, then connect to Power Ref port
Kepco RA55 Power Supply
KEPCO 8 Channel Power SupplyKEPCO 8 Channel Power Supply
•Use PC’s program to control 8 channel all together
•Use Kepco’s program to control one channel at one time
•Always set current limit to protect your system
Up to 15V, 12A each channel
TWT Wait for warm up Gain is adjustable, very high gain(40-
50 dB), Watch out your system’s limitation
Always connect with load at output port before turn the RF output on
Let’s standby and cool down several minutes before turn the power off
Tips for WinCal Key WinCal License KeyWe use a parallel port hub to connect the
license key with 3 computers and 1 printer. The key and the printer is on the top port of the Hub. You can switch it to different computers by pressing the button at the lower part.
Always connect the printer and make sure the printer is working fine. Otherwise the key may not be seen by the computers.
Tip for 85108A The 85108A test set has an option H11. This
option support 2 bands: 1-20GHz or 6-50GHz. It can’t work continuously from 1 to 50Ghz. It means if you measure from 1 to say 30 GHz. The result will be very strange.
Always load the configuration disk when you change the band.
Press Disc->Load->more->Machine Dump->select your band(NP for normal non-pulse measurement)->Load file