[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [TCML] MOTS Tuning, Capacitors, and Spark Gaps
Interestingly, i got all of the capacitors for free! I don't know if this will work for you, but if you go to a metals recycler place, you should find lots, of all different sizes. when the metals place gets the microwave, they have to take out the capacitor, and at the place i got mine, he just threw them in 55 gallon drums. they are mixed in with very high uf, relatively low voltage engine starter motors, but if you dig through, you should be able to get pretty much any capacitance you want. the most common are in the .9 - 1uf range. .8's-.9's are also common. i sorted through 2 55 gallon drums, and found 91 capacitors ranging from .55 - .78. the reycling places have to pay to get rid of the things, so i got mine for free!
Also, i rebuilt my plate capacitor, and managed to get the coil running for about 15 seconds total. nice 4 inch sparks, and lots of purple corona, until the glass gave out again, and cracked allowing the electricity to flow inbewteen the plates.
I will look into those caps for my MMC. Thanks!
Sincerely,
Joel Torgeson
________________________________
From: Jim Mora <wavetuner@xxxxxxxxx>
To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
Sent: Monday, August 24, 2009 4:54:26 AM
Subject: RE: [TCML] MOTS Tuning, Capacitors, and Spark Gaps
Hi Joel,
Wow 80 of them! A lot of us could use some more level shifters! Take heart!
Maybe you can sell them and buy CDC's for a nice performing MMC!
Jim Mora
Much easier to get to 9nf by setting in series one row of .15uf caps: try
16! CDC also makes a .1uf 2kvk caps... 11 should work to get just under 9
nf.
Jim Mora,
PS I did not run these on Java MCC for sizing to coil parameters.
-----Original Message-----
From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On Behalf
Of Lau, Gary
Sent: Sunday, August 23, 2009 6:19 PM
To: Tesla Coil Mailing List
Subject: RE: [TCML] Tuning, Capacitors, and Spark Gaps
Additionally, 80(!) of pretty much any kind of cap in series is going to
have a very high equivalent series resistance (ESR), since resistance is
additive. Resistance in the primary circuit is a performance killer. If
cost is a concern, a beer bottle/salt water cap will do much better.
Regards, Gary Lau
MA, USA
> -----Original Message-----
> From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On
> Behalf Of David Speck
> Sent: Saturday, August 22, 2009 8:00 PM
> To: Tesla Coil Mailing List
> Subject: Re: [TCML] Tuning, Capacitors, and Spark Gaps
>
> Joel,
>
> Well, for starters, microwave oven caps do not have the proper
> characteristics for a TC tank circuit. They are designed for use at 60
> Hz, but are unacceptably lossy at TC tank frequencies. The relatively
> low value internal bleeder resistors will also rob you of power,
> especially working with only a 9 kV NST.
>
> The rest of the description sounds promising. Check the TCML archives
> about MMC capacitors. Those have had an excellent success rate. Not
> exactly cheap, but the will work. MWO caps will not.
>
> Dave
>
> Joel Torgeson wrote:
> > Alright,
> >
> > I've now built my tesla coil, and am very disappointed that it
fails to work. My
> transformer is a 9,000v 30ma NST. I have tailor-built my capacitor out of
capacitors
> from microwave ovens. They are internally resisted, and with 80 of them in
series i
> hit my target capacitance of .0088 uf. My primary consists of 1/4 inch
copper tubing
> spaced 1/4 inch between each winding. there are 15 turns of tubing in a
flat
> pancake configuration. My secondary consists of approximately 760 feet of
24
> AWG magnet wire wrapped around 3.26 inch outside diameter PVC pipe. The
> topload is of the tubing and pie-pan variety, using 3 inch aluminum
tubing/ducting.
> This makes a ~ 15 inch toroid on the top. i am using a 8 ft grounding rod
that isn't
> attached to anything important. There is no metal inside the secondary, so
that isn't
> a problem. My biggest concern is the spark gap. It's a static gap, not
split up into
> multiple gaps, just one big one. it is 5.6mm wide, and has a
> > hair drier running on cool temp, high velocity blowing on it for
quenching.
>
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla