Re: RF Chokes (was Re: Third try at first light)

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

Original poster: Terry Fritz <twftesla-at-uswest-dot-net>

Hi Steve,

	When the main gap shorts, the cap to ground and the series chock will ring
just like the primary circuit.  You are shorting the filter caps out
through the inductor.  This ring may be just as bad as the primary circuit
ring.  Thus "I" would use resistors instead of chokes so there will not be
any ringing.  You may want to check the following especially the last two.

http://hot-streamer-dot-com/TeslaCoils/MyPapers/rcfilter/rcfilter.html
http://hot-streamer-dot-com/TeslaCoils/MyPapers/primarycircuits/pricir.html
http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg
http://hot-streamer-dot-com/TeslaCoils/Misc/Filter.jpg

Cheers,

	Terry


At 12:15 PM 12/8/2000 -0500, you wrote:
>On Thu, Dec 07, 2000 at 07:33:54PM -0700, Tesla list may have written:
>> > $25 is still alot of money to us poor college students. ive seen some
>> > coilers using wire wrapped around some pvc or toilet paper tubes. is
>> > this sufficient for a small coil?
>> 
>> If your talking about RF chokes I don't know. I wouldn't think that it would
>> be enough, but I also thought that the general consensus was steering clear
>> of RF chokes.
>> 
>
>May I ask what the reason for this is?
>
>On my first coil - I used RF Chokes. Ran great. The first time I got lazy and
>connected it up without the chokes (I never made a permenant setup - all the
>parts were seprate) - it burned out my tranny (an oil burner) within a few
>seconds. 
>
>On another ocasion, a while later, I did it again, and was again lazy, and
>burned out an NST (which was half burned before it was given to me) within
>a few seconds. (I am currently depotting both of these trannies to see if
>I can get them working again)
>
>However, the times I ran it with the choke coils - it worked great. My plan
>for the next setup is to make 2 new choke coils (I never liked the old ones
>- long story as to why).
>
>Actually...I was planning to make a sort of high voltage side RF filter
>by hooking a choke coil up to each tranny output and a cap going to ground
>(havn't investigated good values but - I figure a few peices of poly and foil
>should do the job nicely)
>
>Is this a bad idea? I have noticed talk of protecting trannies with large
>resitors and such, what are the advantages/disavantages here?
>
>-Steve
>-- 
>"If you shake it more than 3 times you are playing with it."
>                -- Mike Laramie 
>