I know that the impedance matching ability of a transformer goes like

the square of the turns ratio. However, if I want to have, say, a

25:1 impedance transformation, I could use, in principle, any of the

following number of turns which have a five-to-one ratio:

5 and 1

50 and 10

500 and 100

etc. (There are actually an infinite number of combinations)

How do I know what number of turns to use on the primary and

secondary sides of my transformer if I'm winding my own transformer?

Thanks.

Jim Rybak