Re: RSRG Questions

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 8/28/00 8:22:23 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> Original poster: "Alex Madsen" <alexmadsen-at-netzero-dot-net> 
>  
>  RSRG Questions
>  
>  I am in the process of making my first TC(6x30 15kv 60ma NST).  I have a 
few
>  questions about the spark gap.
>  1.  I some time ago someon the TC list said that an air gap tends to burn
>  out NST, and to use a SRSG. Is this true. Also that it increase the TC
>  performance.


A SRSG is very good and is what I use to get 42" sparks from a
12/30 NST.  I use what I call the Six Keys to Efficiency to design
my coils.  Some of these methods that I use are rather new, and
might not be discussed at any other websites that I know of. 
This coil can be seen at my webpage at:

  http://hometown.aol-dot-com/futuret/page3.html

Just click on Spark Gap Tesla Coils.

A static (non-rotary) gap can be used on an NST powered TC, and
can give good results.  It is possible that the NST may need more
protective circuits when used with a static gap vs. the sync rotary.
The type of gap that most often causes problems is a non-sync,
or async rotary, although this too can be used if the NST is well
protected.


>  2.  I have a 1/7 hp 3450 rpm  induction motor Is this powerful enough for a
>  SRSG? and
>  3.  How can it be 3450 rpm when there are only 2 sets of coils. There
>  appears to be some sort of  device that when the motor reaches  an set
>  (unknown to me speed)  it kills the power to the motor. This could be
>  keeping down the rpms. Has any one run into this before ? I will ask the 
guy
>  at the motor shop next time I am in the area.

If you do the math for the number of poles, the ac line freq, etc, it
works out correctly that 2 poles gives 3450 rpm (considering the slip
in an induction motor).  If you want to make a 3450 rpm motor 
synchronous, you have to modify it by filing or machining two flats on
the armature (squirrel cage rotor).   Yes, 1/7 HP is enough as long as
the rotor disc assembly that you install is not too heavy.  I've
successfully used much smaller motors.

Cheers,
John Freau
>