On Sun, 14 Mar 2004 12:04:18 -0800, John Larkin
posted this:

On Sun, 14 Mar 2004 19:51:50 GMT, James Meyer
wrote:

The other idea is to make a doubler and a trippler fed from the
fundamental and then feed them into a mixer to get the fifth. If the doubler
and trippler are active (class C) stages, you should get as many db out at the
higher frequency as you put in at the fundamental. The mixer can have gain too.
Three transistors, three tuned circuits, and Bob's yer uncle.

Jim


Why not just bandpass filter the 5th from the square wave? Too simple?


John

Because a square wave has to have a particular on to off ratio to get
enough fifth. Because a square wave needs those nasty logic gates. Because
three transistors are simpler.

Jim