Giga-tronics 58542 - 3 Theory of Operation; 3.1 Introduction; 3.2 Circuit Description; 3.2.1 VXI Power Meter System Block Diagram

Preface
Publication 21555, Rev. E, September 2002 iii
3.4 Calibrator Module .....................................................................................................................3-4
3.4.1 50 MHz Oscillator ............................................................................................... 3-5
3.4.2 RF Output ........................................................................................................... 3-5
3.4.3 Oven ................................................................................................................... 3-6
3.4.4 Thermistor Bridge ............................................................................................... 3-6
3.4.5 Track & Hold and DAC ....................................................................................... 3-6
3.4.6 Correction Thermistor Circuit ............................................................................. 3-7
3.4.7 Calibrator NVRAM Control Circuit ...................................................................... 3-7
3.4.8 Sensor NVRAM .................................................................................................. 3-7
3.4.9 Sensor Interrupt ................................................................................................. 3-7
3.4.10 Digital Control Circuit ......................................................................................... 3-7
3.5 Digital PC Board (A2)................................................................................................................3-8
3.6 VXI Processor PC Board (A3) ....................................................................................................3-9
3.6.1 VXI Interface ...................................................................................................... 3-9
3.6.1.1 VXI Gate Array.............................................................................. 3-9
3.6.1.2 Shared Memory .......................................................................... 3-10
3.6.1.3 Shared Memory Decoders.......................................................... 3-10
3.6.1.4 Drivers & Transceivers ............................................................... 3-10
3.6.1.5 Logical Address Switch............................................................... 3-10
3.6.1.6 TTL Triggers & Local Bus........................................................... 3-10
3.6.2 CPU & Memory .................................................................................................3-11
3.6.2.1 Processor.................................................................................... 3-11
3.6.2.2 Real Time Clock/Timer ............................................................... 3-11
3.6.2.3 Interrupt Controller...................................................................... 3-11
3.6.2.4 Bus Error Timer .......................................................................... 3-11
3.6.2.5 Local Address Decoders............................................................. 3-11
3.6.2.6 Drivers & Transceivers ............................................................... 3-11
3.6.2.7 Local Memory ............................................................................. 3-11
3.6.2.8 LED Drivers ................................................................................ 3-11
4
Calibration & Testing
4.1 Introduction..............................................................................................................................4-1
4.2 Equipment Required ..................................................................................................................4-1
4.3 Calibration Procedures..............................................................................................................4-2
4.3.1 Calibrator Output Power Reference Level ......................................................... 4-2
4.3.1.1 Equipment Required..................................................................... 4-2
4.3.1.2 Procedure ..................................................................................... 4-3
4.3.2 Calibrator Output Power ..................................................................................... 4-5
4.3.3 Calibrator Voltages ............................................................................................. 4-7
4.3.4 Calibrator Frequency Check .............................................................................. 4-7
4.4 Performance Tests....................................................................................................................4-8
4.4.1 GPIB Port Check ................................................................................................ 4-8
4.4.1.1 Equipment Required..................................................................... 4-8
4.4.1.2 Procedure ..................................................................................... 4-8
4.4.2 Power Sensor Linearity .................................................................................... 4-10
4.4.2.1 Setup Parameters....................................................................... 4-11
4.4.2.2 Equipment Required................................................................... 4-11
4.4.2.3 Test Procedure ........................................................................... 4-12