Ok so I decided to pull the rpm read out out of my drill press. first off good news it's got a 9v powersupply but the transformer thats next to this board says it's 9vac which is depressing. but it plugs right into this board. this board has a power input and a laser output and emitter/collector connector. so if i'm correct it needs to have a ac to dc converter somewhere on the chip or could the transformer be read wrong. here is a list of every thing thats on the board. every thing is labled with a silk screen except for the ic which is sanded on the top i'm assuming to remove any of the identifying marks.
7 - 150k resistors
1 - 10k resistor
1 - 470k resistor
4 - 15k resistors
5 - 1n4007 diodes
1 - 7530 transistor?
4 - 9012 transistor?
3 - 104 ceramic caps
2 - 30 ceramic caps
1 - 223 ceramic cap
1 - 12 mhz crystal (12.000 KDSY 5B)
2 - 220uf caps 16v
1 - 1uf cap 116v
1 - 20 pin chip of unknown markings (pcb has XTAL next to it)
1 - power connector
1 - 1 emitter/detector connector
could someone look at the picture and make a guess as to what it might be?
it came out of a ryobi 12 inch drill press.