That's mighty brave of you to admit that you have "gaydar", something you have to be "gay" to have. Wow. See how trying to be cute and clever can simply backfire?
You need to catch up to today, old man. I could have called it a "breeder meter" but really it is all the same thing, it is something we all have.
http://en.wikipedia.org/wiki/Gaydar
There is no requirement of "being gay" in order to be able to tell when somebody is likely gay... That's just one of those things gay people try to pretend is "special" to them. Makes them unique snowflakes...