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Re: schematics.........
> Original Poster: "Christopher Boden" <chrisboden-at-hotmail-dot-com>
>
> Alright........idea.
>
> I have seen that Chokes don't work too well. Why not? If the last few turns
> of the sec absorb the most impact, why doesn't a choke work? as it would
> seem these are just a few turns of wire as well. hmmmmmm
There has certainly been a move away from chokes while I was absent from the
list. Personally, I still use and love them. However, there is one HUGE
caveat: you MUST, MUST, MUST design the RLC filter just right, so that it is
absolutely non-resonant and built with just the right choke core
size/material. IMHO, most attempts to add protective chokes are misguided
ones that ultimately hasten destruction of the NST rather than protect it
('cause the chokes resonate with the bypass caps).
So moral of my story is: "If in doubt, leave 'em out!"
>> Start with a good RC filter - it won't take you five minutes (like I did)
>> to
>> rig up four 1.5k resistors, two in series on each NST leg, with bottle caps
>> between the middle of each series pair and RF ground. Try to get resistors
>> rated about 100+ Watts. You'll be laughing, not crying!!!
>>
>> Alex Crow
>
> Where can I get the resistors?
> Can I use something other than a (beer)bottle cap? What value?
Excerpt from a post of mine last month:
I have found a source of 3K 225W Ohmite "Vitreous enameled resistors", for
those who need this type. I got them from http://www.elec-candystore-dot-com
(Dale Ward Electronics). They are $7 each, 900+ in stock. That's what I
just got for my next coil. They are not non-inductive, but they will work
fine. Just don't align them axially under the primary coil ;-)
As for bypass caps, doorknob barium ceramic types work fine. Mica
transmitting caps are also fine and not too awfully expensive. Ditto for
the BLUE glassmikes, which I have seen many times in 0.0005uF (500pf) 20kV.
My own bypass caps are 500pf rolled polyethylene, in 2"x6" PVC tubes. I had
left-over 0.030" poly from building my tank caps, so it was my cheapest and
most logical option.
-Adam
adamsmith-at-mediaone-dot-net