577/Repairs: Difference between revisions

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Next step is adjust and calibrate per the Service Manual.
Next step is adjust and calibrate per the Service Manual.
==Symptom: Power Indicator Light does not come on.==
Found Power indicator lamp holder dangling inside the chassis.
Obvious why the indicator was dark. 
This is a 5V 60 mA incandescent lamp.  Smaller than a grain of rice.  No replacement on hand, but I have a ton of LED's of a similar size and shape.
Unsolder the wires and remove the dead lamp from the holder base.
Fit a suitable LED to the base and select a current limiting resistor to keep the 5V high current supply from burning out the LED.
I have 5V and 15.4 mA going to the LED.  It seems to work just fine.
Solder this holder base to the wire harness.
Plug it in, being careful to observe proper polarity.  Brown is 5V Red is Ground (strange choice of colors, but no one asked me.)
Attach the holder base to the front panel indicator lamp holder.
Turn on and we now have a working power indicator. 
Color is yellow instead of green, but that is of no consequence to me.
[[Category:Instrument repair reports]]

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