Strobe question

incandescent will not work, as others said or implied.

IF you can find a light which runs on battery power, it will not be effected by the fluctuating AC line and should provide a more accurate reading. Also if your strobe disk is small enough, you should try to play a dynamic LP as you are checking for speed by placing the stylus in the outer grooves. This will allow you to account for stylus drag.

I use the KAB strobe which works as described above, but it is expensive and some report not quite as accurate as the Timeline.

I had the same problem when I first got the SDS. I found the VPI supplied strobe disc useless. It was not flat, not round, and fluorescent light hardly worked with it. I got a KAB SpeedStrobe and problem solved. It's $100, but hassle free and simply an essential accessory with the SDS.