UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Driving a piece of electroluminescent tape in lieu of a magic eye

G6Tanuki · 2nd Dec 2019, 3:07 pm

I've thought about this 'fake magic-eye' thing a bit in the past - rather than using electroluminescent stuff I had the idea of using a disc of relatively-thick Perspex/Plexiglass/Lexan or similar, with both faces very finely abraded [2400-grade wet&dry paper] so they're matt and act as a diffuser, then place a green LED behind it.

I even pondered using a few milliamps 'stolen' from the output-valve's cathode to light it: maybe add in an AGC-controlled FET to vary the brightness of the LED to better replicate the function as a tuning-indicator.. Modern green LEDs are really rather bright even at 5mA!

2nd Dec 2019, 3:07 pm	#6
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,007	Re: Driving a piece of electroluminescent tape in lieu of a magic eye I've thought about this 'fake magic-eye' thing a bit in the past - rather than using electroluminescent stuff I had the idea of using a disc of relatively-thick Perspex/Plexiglass/Lexan or similar, with both faces very finely abraded [2400-grade wet&dry paper] so they're matt and act as a diffuser, then place a green LED behind it. I even pondered using a few milliamps 'stolen' from the output-valve's cathode to light it: maybe add in an AGC-controlled FET to vary the brightness of the LED to better replicate the function as a tuning-indicator.. Modern green LEDs are really rather bright even at 5mA!