Re: question about "lambda" (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 20 Aug 2007 22:25:42 -0700
From: Frank <fxrays@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: question about "lambda" (fwd)

Hi, Makes sense for those who played with ham radio.
It means the fraction of the operating wavelength you are interested in.
For TC's, it is the wavelength of your particular 
coil and then a portion of that wavelength.

The relationship of frequency and wavelength is:

lambda =  speed of light in M/s/ frequency where 
lambda is in meters and frequency is in cycles
lambda = 300,000/ frequency when the frequency is in khz

Example:
If a coil is operating at 1 mhz,
1/4 lambda = 1/4 (300,000/ 1000) = 75 meters.
1/2 lambda = 1/2(300,000/1000) = 150 meters
etc

Since coils are all about resonance, you can tune 
them for best performance and design of the 
secondary can be made so be in fractional lengths 
of lambda for a desired resonant frequency and will give better sparks

We used to tune antenna feed lines and antenna 
lengths to fractions of wavelength to get the 
best efficiency out of a particular ham band.
Depending on the type of transmitter, solid state 
or tube, we further tuned them for current feed 
(transistor) , odd multiples of 1/4 lambda, or 
voltage fed (tube) , multiples of 1/2 lambda, to optimize energy transmission.

A few numbers I remember was a 2 meter ground 
plane had 19" radials (tube) and a CB feed coax 
length was best in odd multiples of 9 ft (transistor).

Obviously we will not make a TC secondary 
anywhere near 1/4 or 1/2 wavelength but we can 
design it with lengths to correspond to increments of those wavelengths.

Frank

At 09:08 PM 8/20/2007 -0600, you wrote:

>---------- Forwarded message ----------
>Date: Mon, 20 Aug 2007 12:40:41 -0500
>From: Matthew Boddicker <shmerpleton_town@xxxxxxxxxxx>
>To: tesla@xxxxxxxxxx
>Subject: Re: question about "lambda" (fwd)
>
>It's Matthew Boddicker.
>
>When you say 1/2 or 1/4 wavelength, 1/2 or 1/4 of what? What would be a full
>wavlength? I guess a more accurate question would be, what is the fraction
>compared to?
>
>Thanks,
>Matthew Boddicker
>
>
> >From: "Tesla list" <tesla@xxxxxxxxxx>
> >To: tesla@xxxxxxxxxx
> >Subject: Re: question about "lambda" (fwd)
> >Date: Thu, 16 Aug 2007 20:44:34 -0600 (MDT)
> >
> >
> >---------- Forwarded message ----------
> >Date: Thu, 16 Aug 2007 19:33:46 -0700
> >From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
> >To: Tesla list <tesla@xxxxxxxxxx>
> >Subject: Re: question about "lambda" (fwd)
> >
> >Hi Matthew,
> >
> >Lambda in the electrical sense is simply wavelength, thus 1/2 wavelength
> >or 1/4 wavelength.
> >
> >Wow, 4 pF? Very low and little energy for spark creation. Your question
> >is very interesting. But, how about some specifications on the coil
> >parameters?
> >
> >Take care,
> >Bart
> >
> >Tesla list wrote:
> >
> > >---------- Forwarded message ----------
> > >Date: Thu, 16 Aug 2007 14:25:18 -0500
> > >From: Matthew Boddicker <shmerpleton_town@xxxxxxxxxxx>
> > >To: tesla@xxxxxxxxxx
> > >Subject: question about "lambda"
> > >
> > >Hi, this is Matthew Boddicker
> > >It's either a brain-fart or just a lack of reading the right information,
> > >but what exactlty does "1/2 lambda" and "1/4 lambda" mean exactly?
> > >
> > >Also, probably tied into the same subject, I was tuning my coil by moving
> >an
> > >alligator clip connecting the wire from the primary coil to the capacitor
> > >from the max inductance down to the minumum. I was getting very little
> > >sparks at the beginning, even when I had  the primary circuit the same
> > >calculated frequency as the secondary. The capacitor is 4.075 picofarads.
> > >The "tuned" circuit, to match the same frequency of 438 kHz secondary, is
> > >being given an inductance of 32 microhenrys. But at this inductance (a
> > >grounded rod was held 3.5" away from the top load), there was a tiny bit
> >of
> > >purple corona. This observation was consistant until I hit an inductance
> >of
> > >11microhenrys when many sparks broke out between the top load and the
> > >grounded object. This frequency for the primary is calculated at 752kHz.
> > >That's over 300kHz off! why does that work!?!?!
> > >
> > >Thanks,
> > >Matthew Boddicker
> > >
> > >_________________________________________________________________
> > >Tease your brain--play Clink! Win cool prizes!
> > >http://club.live.com/clink.aspx?icid=clink_hotmailtextlink2
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
>
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