Re: 811A first light

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. John Gudenas by way of Terry Fritz <twftesla-at-qwest-dot-net>" <comsciprof-at-ameritech-dot-net>

Thanks James
Many of us (perhaps not all) building tube coils have found it substantially
easier and cleaner to adjust tank capacitance for tuning as long as the L in
the primary is about where it needs to be. I have accumulated a large
inventory of transmitting micas and variable HV vacuum capacitors to tune
with. Check out the posted discussion with Brent Turner on current limiting.
Get a few more 811A's or one high wattage grid leak resistor. (Go for the
additional tubes as they are cheap and you get a much improved coil).
John W. G.
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, July 10, 2001 9:07 AM
Subject: Re: 811A first light


> Original poster: "James T by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jamest2000-at-att-dot-net>
>
> Hi John,
>  Very nice coil you have. Your careful construction really looks great.
The
> secondary I was using is no where
> near your's in size, but that was just a test.
>  How come nobody seems to use tappable primary's and grid coils(within
> limits I mean)? Seems alot easier than
> changing caps.
>  I will use the original mica cap for current limiting. I don't know what
I
> was thinking anyway, since MOT's
> put out around 2300 volts. Mabey I could remove windings from the
secondary.
>   Regards,
>  James T
>
>
> Tesla list wrote:
>
> > Original poster: "Dr. John Gudenas by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <comsciprof-at-ameritech-dot-net>
> >
> > James
> > The 811A can only handle 175 mA on the plate -at- around 1500 volts. If you
use
> > a MOT with out any current limiting device you will likely melt the
plate.
> > Check out my triple 811A coil on:
> > www.scifair-dot-org/hvdata
> >
> > John W. G.
> >
> > John W. Gudenas, Ph.D.
> > Department Chair of Computational and Natural Science
> > Aurora University
>
>
>