I found?that you insert the blank character differently depending on whether your five letter call is 1x3 or 2x2. If the former, you insert the blank character at the beginning and if the latter you insert the blank at the end. The point is that the third character in the menu?can only be a numeral. When I read the manual carefully?this point is mentioned there?but it is not clearly stated (at least to my mind).?
I am a happy camper now and my WSPR beacon is operating nicely?as I write.
Hiroki AH6CY