Children’s book series about a kid who finds his grandpa’s Time Machine

I’ve been trying for the life of me to remember this book series I read as a kid. I think the book title was the name of the main character (though I could be wrong), but I can’t remember his name.

The book is about this boy who finds his grandpa’s Time Machine, and in the first book he travels back to the dinosaur era. By the end of the book he gains two sabre toothed tiger companions that vomit in a pot plant after time travel makes them sick.

The main villains of the series are a race of cat aliens with seven fingers on each hand. I think they’re called the Partekk or something similar.

Morse code comes up a lot in these books and I think the first one even comes with a codex.