8525B/8528 Technical Service Manual Table of Contents v
Publication No: 15-02036 Issue 6
4.14 Options .............................................................................................................4-36
4.14.1 F—Fan Assembly..........................................................................4-36
4.14.2 LU—Switched LSB Operation......................................................4-36
4.14.3 L—Lower Sideband Operation .....................................................4-37
4.14.4 M—CW Facility............................................................................4-37
4.14.5 PH—Headphone Output ...............................................................4-37
4.14.6 R—Extended/Remote Control Interface.......................................4-37
4.14.7 AD—Antenna Driver ....................................................................4-37
5 Operating Instructions
6 Maintenance
6.1 General ...............................................................................................................6-1
6.1.1 CMOS Devices................................................................................6-1
6.1.2 Circuit Boards .................................................................................6-1
6.1.3 Transmitter Precautions...................................................................6-3
6.1.4 Probe Precautions............................................................................6-3
6.1.5 Surface Mounted Components........................................................6-3
6.2 Fault Diagnosis...................................................................................................6-4
6.2.1 General ............................................................................................6-4
6.2.2 Voltage Measurement......................................................................6-5
6.2.3 Front Panel Controls........................................................................6-6
6.2.4 Logic Levels....................................................................................6-7
6.2.5 No Reception...................................................................................6-7
6.2.6 No Transmission .............................................................................6-8
6.2.7 Unlocked Synthesizer......................................................................6-8
6.2.8 Typical PA Voltages........................................................................6-8