I realize that the majority of the discussions here are on QRO matters but once in a while the subject drifts off to the quality of our output rather than the quantity. So, here's something interesting for the stages earlier on in the P.A. chain:http://www.ti.com/lit/gpn/lmh6703
About 0.4 watts into a 100 ohm load using a +/- 5v supply
1.8 GHz bandwidth
2nd Harmonic -87dB below carrier @ 5 MHz, -69 dBc @ 20 MHz
3rd Harmonic -100 dB below carrier @ 5 MHz, -90 dBc @ 20 MHz
IMD -80 dB below carrier @ 50 MHz 5 dBm/tone
Available in quantity at about two bucks each.
So, we can use these as the lower stages of the P.A. chain, what can we use further down the line where real power is involved?