[TenTec] Argo V and digital modes

[ken.d.brown at hawaiiantel.net]

You're right about the transients and the sidebands they create. Keyed
CW creates sidebands too. I don't think those sideband components could
be accurately called intermodulation products though. 

> But there is a discontinuity that results from switching between the two frequencies, which produces transients that will excite intermod. Think about it -- even if you manage to switch at a zero crossing, the resulting waveforms have two different slopes by virtue of their different frequencies.
> 
> If you doubt that, look at the spectrum of your "real FSK" in an analyzer set for high frequency resolution.