The BF3 tubes require a very fast, very sensitive front end amp. It must be capable of reproducing and amplifying 60 nanosecond pulses faithfully and handle millivolt level signals riding on 2000 volt dc levels. (simple 3kv disk capacitor often used to couple to amp).
Most often, in surplus counters, this is handled by an ingeniously designed single or two stage discrete transitor amp. There are a number of good modern linear IC's which might handle the job available now.
Richard Hull
Created on Friday, February 16, 2001 5:21 PM EDT by Richard Hull