I recently converted my aging YBA Integre DT's volume control to a remote Alps kit purchased off of eBay for the reasonable price of about $40 and am very happy with the results, but in the process, I spent way too much time puzzling over the power LED circuit. That sounds ridiculous until you know how it's powered.
The power switch is a DPDT that disconnects both legs of the power from the IEC C14 connector. When the switch is off, the LED is shorted by the "unused" throw of the DPDT switch.
When the switch is on, the LED has no complete circuit, but it lights! Voltage measurements with a Fluke DVM gave 37 VAC or 30 VDC across the LED when it was lit. I've searched this forum and googled it, and I've found no reference to this weirdness.
I'll leave the answer as an exercise for now.
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Topic - Odd means of lighting an LED in YBA Integre DT. - h_h 13:27:15 01/25/11 (4)
- RE: Odd means of lighting an LED in YBA Integre DT. - Nagratech 08:17:57 01/26/11 (3)
- RE: Odd means of lighting an LED in YBA Integre DT. - h_h 11:27:17 01/27/11 (2)
- RE: Odd means of lighting an LED in YBA Integre DT. - Michel 20:48:16 02/03/11 (1)
- Thanks, I didn't see it, but I'll look again. - h_h 10:22:57 02/04/11 (0)