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swordholder · 27th Feb 2010, 8:26 pm

Andy,
Yes I did fit a 3mm LED to each switch as an indicator to show which position of the knob was selected. Originally I wanted something "more professional" than a simple felt tip mark as I was not sufficiently adept with a small paintbrush to paint a spot.
I did originally glue the LEDs in place, but decided to light them up as a bit of "flash". They are connected in series across the LT supply, with , if I remember rightly a 2k2 reistor in series.
They serve no other purpose other than to show the switch position and could be omitted and another method used.

Regards
Mike

27th Feb 2010, 8:26 pm	#194
swordholder Rest in Peace Join Date: Aug 2009 Location: East Preston, Sussex Posts: 162	Re: The "Sussex" Homebrew Valve Tester. Andy, Yes I did fit a 3mm LED to each switch as an indicator to show which position of the knob was selected. Originally I wanted something "more professional" than a simple felt tip mark as I was not sufficiently adept with a small paintbrush to paint a spot. I did originally glue the LEDs in place, but decided to light them up as a bit of "flash". They are connected in series across the LT supply, with , if I remember rightly a 2k2 reistor in series. They serve no other purpose other than to show the switch position and could be omitted and another method used. Regards Mike