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).
Power Supply Load Resistance Readings to Ground
Load
+20V line
- 20V line
5V reg. line
8V line
3.3V reg. line
9V reg. line
5V reg. line
3.3V reg line
2.5V reg. line
* Ohmmeter set to 2k-ohm range. Negative lead grounded.
Figure 9 - Voltage Distribution
Location
Resistance *
P6/pin 1
800 ohms increasing
to infinity
P6/pin 4
0.754 k ohms
P7/pin 5
infinity
P7/pin 7
infinity
P9/pin 1
0.331 k ohms
P9/pin 3
0.330 k ohms
PS2/pin 5
0.308 k ohms
PS2/pin 7
0.879 k ohms
PS2/pin 9
infinity
Table 6
15
Destination
Audio amp Z Bd.
Audio amp Z Bd.
DG Bd. via PS Bd.
5V regulator PS Bd.
LCD Engine L Bd.
DG Bd.
DG Bd.
DG Bd.
DG Bd.