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Re: "High Frequency" Neon Transformers??

Tesla List wrote:
> 
> Original Poster: "John" <jbowers1-at-jnlk-dot-com>
> 
> Hello all,
> 
> First of all, I'd like to thanks everyone who responded to my previous
> transformer inquiries.  The information provided will be very useful.
> 
> Has anyone heard of high frequency neon transformers?  These are supposed to
> be based on 10 Khz output instead of 60 Hz.  I've also been told that
> they're mostly solid state and MUCH lighter than a conventional neon of the
> same size/ rating.  Anyone use one of these for a Tesla coil driver?  How
> well/ poorly does/ did it work?   Where can one of these be obtained?
> 
> Thanks,
> John Bowers
-----------------------------------------------------------------
John, ALL

I know a former coworker who is now the Chief EE for a firm which makes
these devices.  They are basically a off-line switch mode power supply
(half-bridge circuit for the SSTC interested crowd), running in constant
current mode into a step up transformer with ground fault detection/
monitoring and automatic shutdown.  The open circuit turns ratio of the
HV transformers is designed to produce 12-15kV based on size and current
capability.  The circuit also has a high speed GFI built into it for
fire and long term fault protection. The operating frequency of the 12kV
30mA unit I have in my possession is 25Khz.  

These units will operate a Jacob's ladder fine, and the transformer
is vacuum epoxy impregnated to operate up to 20-25kV (turns ratio
dependent).  I do believe that the GFI internal to the device will
disable the unit in short order with EMI/RFI coming back from even a
small SG driven table-top TC.  Unit must be powered down and restarted
to reset fault and allow unit to resume operation.

The main advantages of this unit are:
1. Safer (detection of external faults, arcs, short circuits and
   automatic shutdown prior to a fire).
2. Better power factor, larger units (15kV, 60mA) have PFC built
   into them with PF of 0.95 or better under all operating conditions.
3. Smaller and lighter then transformers they are replacing.
4. Cost is comparable or cheaper then replacement transformers.

Most newer neon signs are using this new solid state power supply
technology.

Regards

DAVE SHARPE, TCBOR
Chesterfield, VA USA

PS:  Company that manufacture's the unit I have is "Everbrite". 
I'm         sure there are competing manufacturers of similar products. 
This is not intended to endorse one product over another, just provide
general tech info on operation of unit.