I have used almost every amp for RTTY there is and IMO the best is an Alpha 9500. Expensive but worth it. Auto band change, autotune, handles SWR up to 3:1 with no external tuner, easy to read bargraphs and full legal limit 1500 watts with no time limit. Only major drawback: Does not do six meters but does 160-10. 73, Bill W6WRT