Tektronix 2213 Instruction Manual page 143

Each regulated supply has numerous feed points to external loads throughout the instrument. The power
distribution diagram is used in conjunction w ith the schematic diagrams to determine those loads that can be
isolated by removing service jumpers and those that cannot.
The power distribution diagram is divided into circuit boards. Each power supply feed to a circuit board is
indicated by the schematic diagram number on w hich the voltage appears. The schematic diagram grid location
of a service jum per or component is given adjacent to the component number on the power distribution diagram.
If a power supply comes up after lifting one of the main jum pers from the power supply to isolate that supply, it
is very probable that a short exists in the circuitry on that supply line. By lifting jumpers farther down the line, the
circuit in w hich a short exists may be located.
Typical resistance values to ground from the regulated supplies output as measured at the supply test points
are:
+100 V
Resistance values significantly lower may indicates shorted components in the load. Values w ill vary between
instruments.
Always set the POWER sw itch to OFF before soldering or unsoldering service jum pers or other components
and before attempting to measure components resistance values.
POWER SUPPLY ISOLATION PROCEDURE
114 fia tT P 5 0 0
-8 .6 V
+8.6 V 95 f i at W 975
+5 V 330 f i at W 985
+30 V 905 f i at W 965
12.5 k fi at W 966