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Intro and NST hints

Hello coilers everywhere !                                    As a new
member of the TC Mailing List , thought I would give a brief intro to
myself .My business is producing high quality neon tubes for signage ,
lighting , sculpture , and plasma art . My hobby is , of course , Tesla
coils and other H.V. related stuff . I've been coiling for about 10
years (on and off) , but have ALWAYS had a fasination with electricity
and light ,(Strange , how both business and hobby contain those same two
elements) Most coils to date have have been under 1 KVA , but I'm
collecting parts for one in the 2.5 KVA range.      I'm sure I'll have
lots of questions once I start building this coil , but for now , here's
a hint on finding cheap (if not free) neon transformers and how to use
them. This applies to 12 & 15 KV , mid-point ground , balanced output
transformers.(all 12 &15 KV NSTs in U.S.A. that I've seen are of this
type) The failure mode of a lot of these type NSTs is a shorted or open
secondary on only one side , which renders them as junk to the sign
trade. Therefore, most neon sign shops will sell 'bad' NSTs for little
or nothing. However , very often , the other side of the secondary still
works fine (-at- 1/2 of rated sec. voltage) , from mid-point ground to the
good HV terminal. (Caution-as this puts one side of your charging
circuit at ground potential) Want more voltage ? Find two of these
'half-bad' NSTs , preferrably of the same brand   and case style , but
allways of the same voltage and current ratings. Note and cap off bad HV
terminals and do not use. Connect the sec. mid-point ground terminals
together (usually a 1/4 X 20 stud on one end of the case). Connect case
grounds together and to the grounded (green in U.S.A.) wire to the 120
volt supply line. Now connect the primaries in paralell and energise. If
there is no voltage across the good HV terminals, reverse primary
connections on one transformer only.You should now have a 'good'
NST(electrically speaking) made from two 'bad' ones. ATVANTAGES:
cheapness , good low cost approach for beginners , or bringing that new
coil into tune , without risking burnout of a good NST. DISATVANTAGES:
twice the size , weight , and power requirements of one NST.
Happy & safe coiling to all,                                   Tony
Greer , a.k.a. Special Effects Neon , Lubbock , Texas