Although resistance measurements vary greatly depending on the type of ohmmeter,
table 6 shows resistance values that you can use for relative measurements. All
resistance values were taken using the same range (ohmmeter ranges have different
output voltages and current, so readjusting the meter ranges could not be done for
relative measurements).
Figure 9 - Voltage Distribution
Power Supply Load Resistance Readings to Ground
Load Location Resistance
*
Destination
+20V line
P6/pin 1
800 ohms increasing
to infinity
Audio amp Z Bd.
- 20V line
P6/pin 4
0.754 k ohms
Audio amp Z Bd.
5V reg. line
P7/pin 5
infinity
DG Bd. via PS Bd.
8V line
P7/pin 7
infinity
5V regulator PS Bd.
3.3V reg. line
P9/pin 1
0.331 k ohms
LCD Engine L Bd.
9V reg. line
P9/pin 3
0.330 k ohms
DG Bd.
5V reg. line
PS2/pin 5
0.308 k ohms
DG Bd.
3.3V reg line
PS2/pin 7
0.879 k ohms
DG Bd.
2.5V reg. line
PS2/pin 9
infinity
DG Bd.
*
Ohmmeter set to 2k-ohm range. Negative lead grounded.
Table 6
15
