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RE: Building A VTTC, staccato pcb

Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

Hello VTTC builders,

A couple of years ago a silk screened staccato PCB was available. There may
be a few left out there floating around. They were very nicely made and the
bugs were mostly out. It was somewhat of an open, joint project, including
FutureT (aol) check his home page. The maker is on my tongue tip, sorry.

I was very easy to assemble.

Jim Mora
Long Streamers

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Wednesday, August 23, 2006 11:09 AM
To: tesla@xxxxxxxxxx
Subject: Re: Building A VTTC

Original poster: Mddeming@xxxxxxx

Hi Dr. H,

The staccato contrrollerr must be more than just a pulse-width
controller. PWCs cannot lower the frequency at which the pulses
occur, only their width., ie you can't get 20 PPS from a 60 Hz source
with just a pulse-width controller.
While any tube can be operated far below its design parameters for
longevity, some tubes are designed so that, when operating properly,
they are  in the "glowing plate mode" without melting. When in doubt
R.T.F.M.   (RCA TT-5)  ;^)

73s / 88s ???
Matt D.

In a message dated 8/23/06 9:01:20 A.M. Eastern Daylight Time,
tesla@xxxxxxxxxx writes:
Original poster: "Henry Hurrass" <Dr.Hankenstein@xxxxxxxxxxxxx>

I think the whole idea of the staccato controller in the first place is to
limit the "watts dissipation" that the plate really thinks it's seeing. As
an example, if you limit the duty cycle to say 50%, you could conceivably
double the plate dissipation (thus producing a longer spark), but the
"average plate dissipation" would still be below the "max plate
dissipation" allowed for the tube. I.E.: 500W times 50% duty cycle equals
250W avg. = longer spark. Without the staccato controller (which is really
only a pulse width or duty cycle controller AKA: CW Mode) the plate would
normally melt. I personally do not like to see plates glowing any color
other than black for longevity of the tube. Who cares what the BBS rate is
as long as you find the sweet spot where you would back-off the duty cycle
to make your coil a long time AND a long spark performer. Look at the
plate: If it's glowing, you are probably giving too much "hammer".  enjoy
and BTW nice work!

Dr. Hankenstein