Brontekst bekijken van SBM-20

{{Project
 |Name= SBM-20
 |Picture=
 |Omschrijving= Investigating the old soviet SBM-20 geiger tube
 |Status=Initializing
 |Contact=thomas
}}

== 4-in-1 counter ==

Building a four-in-one geiger counter, to compare tubes with. 

[[File:Four sbm tubes.jpg|thumb|left]]

[[File:Quadruple geiger.jpg|thumb|left]]