What kind of lamp to use with a stroboscopic disc?

@stringreen 
many thanks for the quick response. It's odd – I thought fluorescent was the case. So I tried a fluorescent desk lamp that I have and it didn't work. I will look into one of those night lights that you talk about.

@miner42 
Would you be so kind as to walk me through how to use that app with a turntable? The documentation is pretty thin. Thanks!