Re: OLTC update - Poor seconadry Q

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Terry,

On 30 Aug 2002, at 15:21, Tesla list wrote:

> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> 
> Hi All,
> 
> I have adjusted my coil as best I can but the output still seems "weak".  I
> think I now know why.  My secondary Q is only 36.  That works out to a
> secondary AC resistance of about 3300 ohms!!  R = 2 x pi x F x L / Q

Thankyou for confirming my suspicions.

Regards,
malcolm

 
> Paul - The pinger file is here if your are interested.
> 
> 	http://hot-streamer-dot-com/temp/OLTCsec.CSV
> 
> The waveform is at:
> 
> 	http://hot-streamer-dot-com/temp/OLTC08-30-01.gif
> 
> Just to give an idea of how bad this is...  I am pumping and quenching 317
> watts into the secondary system.  53 watts is going to streamers and a
> stunning 264 watts is going into heating up the secondary!!!
> 
> So 83 percent of the power is "lost" :-((
> 
> Some notes are at:
> 
> 	http://hot-streamer-dot-com/temp/OLTCnotes.txt
> 
> The entries at the last tell of the Q=36 case.
> 
> So... I don't know if it is the SonoTube, surroundings, proximity effects,
> plastic wrap coating...  Have to test some things...  A small chance it
> could be the anti-parallel diodes...
> 
> Of course, this is not a problem with the basic OLTC technology, that works
> great!, but rather an age old problem of making secondaries without really
> low Q...
> 
> Of course, ideas on how I can fix this are more than welcome :-)) 
> 
> The specs of the secondary system are:
> 
> L = 480mH
> Wire gauge = #28
> Turns = 2760
> Winding length = 41 inches
> Diameter = 10.75 inches
> Q = 36.0  :-p
> Fo = 38.2kHz
> Csec = 35pF
> 
> Torroid 24" diameter x 6.5" cord    
> Center or toroid 3.5 inches above last secondary turn.
> 
> Cheers,
> 
> 	Terry
> 
> 
> 
> 
>