[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: ...sounds totally newbie, but...



Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi,

I have some foot long 200K power resistors.  But I think you also need a 
say 5pF cap in series too that needs to take like 250kV!!  If anyone wants 
to experiment, I would be happy to donate the resistor part.

Cheers,

         Terry


At 03:53 PM 1/31/2003 -0800, you wrote:
>If you're just trying to tune the primary, etc... and want to dump the 
>energy, why not a resistor in the circuit that provides a load comparable 
>to that of the secondary.   I believe that Terry modeled the secondary 
>load as a 220K resistor with reasonable success (comparing waveforms 
>against spice).. So.. if you could transform that 220K at the secondary to 
>something equivalent in the primary.
>
>Another way to choose the resistor would be to calculate the approximate 
>reactance of the primary at your approximate resonant frequency and then 
>use a resistor that is 10-15 times that (i.e. a loaded Q of 
>10-15).  Sample calculation: 0.08 uF primary capacitor, 200 kHz...  about 
>10 ohms reactance.. so a 100-150 ohm resistor  might work..
>
>
>At 04:32 PM 1/31/2003 -0700, you wrote:
>>Original poster: "Christopher \"CajunCoiler\" Mayeux by way of Terry 
>>Fritz <teslalist-at-qwest-dot-net>" <cajuncoiler-at-cox-dot-net>
>>
>>Ok, it's coming back to me now.
>>The question that arises now, would be how one might go about
>>constructing a "dummy load" that could dissipate the power at
>>a reasonable level... and at the same time, be re-useable on
>>nearly any other new coil...
>>...just a thought.
>>---
>>C.L. Mayeux
>>Owner, MSB Data Systems
>>http://www.msbdatasystems.tk
>>
>> > -----Original Message-----
>> > From: Tesla list [mailto:tesla-at-pupman-dot-com]
>> > Sent: Friday, January 31, 2003 4:41 PM
>> > To: tesla-at-pupman-dot-com
>> > Subject: Re: ...sounds totally newbie, but...
>> >
>> > Without the secondary in place, the gap dissipates almost all the
>> > power as
>> > heat.  The primary current is also maybe 2X higher.  That is
>> > "maybe" ok,
>> > but just be aware of it.
>> >
>> > Operating without the spark gap with resonant sized caps is a sure killer
>> > of NST or caps.  But having the spark gap in circuit should
>> > protect in that
>> > case since the gap will keep the voltage from going too high.
>