Re: Cold Cathode Transformer

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "BRIAN FOLEY" <ka1bbg@xxxxxxxxxxx>

Hi, worked in a sign shop years ago, we built a sign for the shop 75 feet
tall, used 9 pieces of 25kv at 120 ma for white cold cathode, the sign was
so bright lifting out of boston, mass you could see the glow in the sky.
about 38 miles from the airplane.  cul brian f.
----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Wednesday, January 18, 2006 5:35 PM
Subject: Re: Cold Cathode Transformer


> Original poster: FIFTYGUY@xxxxxxx
>
> In a message dated 1/18/06 7:01:33 AM Eastern Standard Time,
> tesla@xxxxxxxxxx writes:
>
>  >Cold cathode tubes do not require the heating
>  >elements as neon tubes do, thus, they have immediate start up, can
>  >also be dimmed, and have long life. The tube is what is actually
>  >"cold cathode", and the transformer current simply needs to be
>  >capable of starting it.
>
>      I thought all neon lighting was cold cathode? I know some
> fluorescents are cold cathode - are these what you're thinking of?
> Not sure why anybody would want to dim neon (although a friend of
> mine did so for a display in his house, using a variac).
>      15kV seems like an awful lot of voltage to start a fluorescent
> bulb - don't they all contain, by definition, mercury vapor that the
> neon tube lacks?
>      120mA also seems on the a low side of running current for even a
> single fluorescent bulb?
>
> -Phil LaBudde
>
>