||I know who buzzes in first becuase their light comes
and no one else's can activate until the circuit is reset.
The schematic I used to make the circuit is shown below, compliments of Bill Bowden .
His page has a parts list. I used a few substitutes; for the SCR's,
10uF capacitor, and the 7.5K 5W resistor:
I got my SCR's from allelectronics.com , and they were 400V, 4A
For the 10uF capacitor, I used 30uF, 300V
And for the 7.5K resistor, I used 50K,5Watt
When I first completed the circuit, all three 25W lamps would come on,
and the relay would come on repeatedly. After emailing Bill for help, (thanks, Bill!)
I upped the capacitance on the 10 uF to 30, and began increasing the 7.5K resistor.
As the resistance went up, I knew I was going in the right direction because at about
25K, only two lamps would come on. Then at 50K, it worked like a charm.