Windows 7 based "code practice oscillator" interfaced to WinKeyer USB. I don't like the units audio out. Bonus points if it reads the code as well.
Confused what you want. But I bet the solution doesn't involve a computer.
Winkeyer's sidetone frequency can be adjusted to several different frequencies but is always a square wave. No matter what Windows program you run... winkeyer's built in sidetone is always a square wave.
If you want to key a different code practice oscillator whose note you do like, using the Winkeyer or any other keyer, you just plug the CPO's "key in" to the Winkeyer's "KEY1" and make sure the Winkeyer's sidetone is disabled.
A nice simple sine-wave CPO is illustrated here: http://www.nt7s.com/blog/2008/11/nt7s-code-practice-oscillator/
If you want something different... let us know!