Power Supplies
Verify the power supplies generated on the 34970-66501 circuit board.
The front panel filament voltage, + 5 V backplane and +5 V fan are
switched by the On/Standby switch. All other power supplies operate
whenever the AC power cord is connected.
To check the power supplies, remove the instrument cover as shown
on page 174. The power supplies can be checked from the bottom of
the instrument as shown below. Be sure to use the correct ground
point when checking the supplies.
+
–
Continued on the next page...
W a r n i n g
•
Exposed Mains
•
Do Not Touch
+18 V float
–18 V float
+5 V float
Ground Float
6 Vrms filament
Chassis
Earth Reference
+5 V Earth Referenced
3 V battery
6
Chapter 6 Service
Troubleshooting Hints
165
Summary of Contents for 34970A
Page 1: ...Agilent 34970A Data Acquisition Switch Unit Service Guide ...
Page 34: ...32 ...
Page 35: ...2 Quick Start 2 ...
Page 49: ...3 Front Panel Overview 3 ...
Page 62: ...60 ...
Page 63: ...4 Calibration Procedures 4 ...
Page 118: ...116 ...
Page 119: ...5 Theory of Operation 5 ...
Page 159: ...6 Service 6 ...
Page 177: ...General Disassembly 4 3 2 1 6 Chapter 6 Service Disassembly 175 ...
Page 178: ...Internal DMM Disassembly 3 2 1 Chapter 6 Service Disassembly 176 ...
Page 180: ...Additional Chassis Disassembly 1 2 Chapter 6 Service Disassembly 178 ...
Page 181: ...Plug In Module Disassembly Needle nose Pliers 6 Chapter 6 Service Disassembly 179 ...
Page 182: ...180 ...
Page 183: ...7 Replaceable Parts 7 ...
Page 220: ...Chapter 7 Replaceable Parts Manufacturer s List 218 ...
Page 221: ...8 Schematics 8 ...
Page 272: ......