Keypad Test; Front Panel - Stanford Research Systems SR810 Manual

Front Panel

the number of on LED's until all of the LED's are off. The SR810 is still
operating, the output voltages are updated and the unit responds to
interface commands. To change a setting, press any key other than
[Phase] or [Freq] to return to normal operation, change the desired
parameter, then press [Phase] and [Freq] together to return to the test
mode. Turn the LED's all off with the [Phase] key.

Keypad Test

To test the keypad, press the [Phase] and [Ampl] keys together. The
displays will read 'Pad code' and a number of LED indicators will be
turned on. The LED's indicate which keys have not been pressed yet.
Press all of the keys on the front panel, one at a time. As each key is
pressed, the key code is displayed in the Reference display, and nearest
indicator LED turns off. When all of the keys have been pressed, the
display will return to normal. To return to normal operation without
pressing all of the keys, simply turn the knob.
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