the Electricgermkiller site for instructions on how to  build--Testimonials 
on use & safety >> Lois --- It is a yahoo group  & well worth your 
time._germkiller  sign in_ (http://health.groups.yahoo.c
om/group/microelectricitygermkiller/?v=1&t=search&ch=web&pub=groups&sec=group&slk=1)
  
 
In a message dated 2/8/2013 7:19:10 P.M. Eastern Standard Time,  
[email protected] writes:

Thanks.  I have the Clark zapper, which I bought off ebay a  few years 
back, which is 30kHz only.

I found the following plans for a  15Hz zapper, I may have to give it a go.

_http://www.ryanmcginty.com/orgone/zapperinfo.pdf_ 
(http://www.ryanmcginty.com/orgone/zapperinfo.pdf)