One missile-launcher that should get the pulse going (10)
I believe the answer is:
peashooter
'one missile-launcher that should' is the definition.
The definition suggests a singular noun which matches the answer.
'get the pulse going' is the wordplay.
'get' is a charade indicator (letters next to each other).
'the pulse' becomes 'peas' (I've seen this before).
'going' becomes 'hooter' (I am not sure about this - if you are sure you should believe this answer much more).
'peas' put next to 'hooter' is 'PEASHOOTER'.
Can you help me to learn more?
(Other definitions for peashooter that I've seen before include "Primitive weapon" , "Toy weapon" , "Child's "gun"" , "child's toy" .)