Repeats first: cracking a vertical code
Find a letter that appears twice, ask what those two figures have that the others don't, and the letter has told you what it means. One position at a time, and check every letter before you commit.
Codes
2 posts on this. Written by Mat and Alicia, who prepare pupils for the Buckinghamshire Transfer Test every week in Winslow.
Two letters, two jobs
The top letter and the bottom letter never describe the same thing. Cover one with a finger, solve the other, then swap — and prove each rule against a box that does not have that letter.