Gives fully variable total spectrum floodlight output under remote control.
Or it would but nothing now. Full of dust and fluff in the control area and
a long term heat damaged , so presumably dramatically raised ohmage
resistor.
The bands are not discoloured , I think, reading 100 ohm , 5 percent and 1W
size. Currently reading 47K, but scraping back the end thirds of the metal
oxide spirals , the outer section thirds to each end are about 500 ohm each.
This resistor connects mains live to in-series opto-coupler, then small 3W
mains transformer primary (supplying just a 7805 for the microcontroller)
then neutral.
The opto is 4 pin P620 , presumably Toshiba TLP620 , current going through
back to back LED of 50mA rating with transistor receiver.
For the UK a 3W transformer would take about 12mA so 1.2V dropped across 100
ohm, does that seem about right ? presumably uprating to 2Watt, 100R. The
LED side of the opto seems ok at 1V diode drop either way.
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/