First, just do all of your antenna tuning on ch 20. When it is at minimum SWR on 20 it will be as good as it'll get on 1 & 40 too.
Check the antenna mount's ground connection, it is critical to obtaining the lowest possible SWR. Are you using Firestik's Firering or conventional mount? Also, springs can make tuning an antenna more difficult in several ways, the least of which the spring makes the antenna electrically longer than can sometimes be tuned for.
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