amplifier for output of THDB_ADA

[Altera_Forum]

I have an OFDM transceiver with SMA output from the THDB_ADA (Terasic) board. I need to amplify this output to drive a line. I am asking for about 1 AMP into a variable load (between 10 ohms to 600 ohms) at frequencies between about 300 kHz and a few MHz. 

 I have struggled to find an amplifier able to do this. Does anyone have any suggestions on how I might do this?

[Altera_Forum]

1A into 600 ohms is 600 V. Do you mean it? Not impossible, but it restricts the amplifier offer to a small choice of special high voltage amplifiers, e.g. from APEX/Cirrus. For clarity, you should specify the intended output voltage range and impedance of the amplifier. 

 THDB_ADA has AD and DA channels have a high pass characteristic by their input and output transformers. For 300 kHz transmission, you possibly should bypass it.

[Altera_Forum]

Actually, yes, 1A into 600 Ohms would be too much. The input impedance is non-constant and frequency dependent because of multipath effects on the power line. My simulations suggest that it will vary between 10 Ohms and about 300 Ohms and also have spikes at certain frequencies. Impedance matching will be extremely difficult so I guess my aim is to couple sufficient power to carry the signal from one part of the line to another. 

 To increase the power, i'm looking for an amplifier able to operate between about 0.5 MHz and 5 MHz. Output power about 20W I guess. I haven't been able to find such an amplifier - it seems like the no man's land between audio and RF.