RE: [TCML] 7.5V 52A Filament Transformer for 3CX3000 Needed

["Lau, Gary" <Gary.Lau@xxxxxx>]

Cameron,

I can appreciate your desire for a factory-made transformer over a DIY hack.  A well-performing coil that looks like trash just isn't too special.  So I understand if this isn't something worth considering, but it may be for others.

If one started with a junked variac - one with burnt windings or a missing brush assembly or whatever, that would make a superb foundation for winding a low voltage heavy gauge secondary.  It's easy to wind on, doesn't have the saturation issues of a MOT, and one could then easily fine-tune the secondary voltage by choosing the primary tap point (soldered).  Maybe pre-solder a couple of primary taps prior to winding the secondary...

Regards, 
Gary Lau
MA, USA

> -----Original Message-----
> From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On
> Behalf Of Quarkster
> Sent: Monday, June 15, 2009 12:59 AM
> To: Tesla Coil Mailing List
> Subject: Re: [TCML] 7.5V 52A Filament Transformer for 3CX3000 Needed
> 
> Steve -
> 
> The biggest advantage of using a variac in conjunction with a filament
> transformer is the ability to "dial-in" the correct filament voltage.
> Depending on when they were made, you may find filament transformers with
> 115, 117, 120, or 125 volt primaries.
> 
> With a variac, you can set the correct filament voltage regardless of
> transformer input voltage rating, variations in local line voltage, or line
> voltage "droop" in your equipment when everything is operating at full load.
> Obtaining maximum tube life is VERY dependent on maintaining correct
> filament voltage.
> 
> Regards,
> Herr Zapp

_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla