[karesz*]

Yes, its possible to replace a mech-chopper with Reeds, but what abot reliability?
You have to calculate with i.e. 10 millions of correct switching-and how many hours are there if we assume a switching frequency of some 100 Hertzs?
We can find an impulse generator from -I think- Ortec they has Reed switched circuit for Nuclear Physics and is an old development from later 50s or early 60s but its a relative unknowed equipment and nowadays is no more reliable...