HP 8112A Operating, Programming And Servicing Manual page 46

Switching On
4-2 Operating
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Figure 4-1. HP 8112A Front Panel
The HP 8112A performs a "self test" when the power is switched
on. All the front panel LEDs should light momentarily. If a fault is
detected, the word "ERROR" is illuminated and an error code is
displayed on the front panel digital display. The possible error codes
are:
A key is stuck in the depressed position.
Fail RAM test
Fail Period Timing test
El2
Fail Delay Timing test
El3
Fail Width Timing test
El4
Fail Slope Generation test
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