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

Re: [TCML] Tuning primary to secondary with a scope

It's good to remember that Leon Theremin invented his instrument (basically, a collection of small Tesla coils--well, almost) without a scope. Pretty remarkable, when you think about it. 

===Carl






This is the reason scope tuning is of little value for accurate tune at high power.

By all means use scope to tune ballpark then full power runs followed by small primary tap changes is the way to dial in the final tune. Keep in mind this will change every time you run the coil in different surroundings.

I thought you classic coil boys would be against all this modern scope stuff anyway ;)


Colin Heath




On 21 Mar 2012, at 09:54, Phil Tuck wrote:


Snip" and in real life, the resonant frequency of the secondary comes down
from the capacitive loading of the sparks, once it starts to break out."

Yes that is something most people forget! I run dummy streamers out from the
toroid (bits of wire contacting the toroid surface, but isolated the other
end) and measure the secondary again. Different lengths and differing angles
will all produce different results. I go for a figure a bit lower than the
average result, and tune the primary to that.
My secondary is 82 kHz while I tune the primary to 72 to 73 kHz. I try to do
this at any venue that is inside, as ceiling height (usually 6 to 7 feet
where I go) affects things considerably in a medium coil
Moreover, if your coil only puts out 4 foot, there is little point in
simulating a streamer with 5 foot + of wire!

Regards Philip Tuck
www.hvtesla.com.

.


-----Original Message-----
From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On Behalf
Of Jim Lux
Sent: 20 March 2012 21:58
To: tesla@xxxxxxxxxx
Subject: Re: [TCML] Tuning primary to secondary with a scope

On 3/20/12 12:40 PM, Phil Tuck wrote:

To scope the secondary I just remove the RF earth and feed the signal
into the base and use a probe as an aerial, as far away as you can
pick it up still. Even then if someone walks past [say] 8 foot away on
a medium sized coil, you can see the effect on the scope.

There is a difference in the results gained between scoping them
separately (probably the correct manner) or with both sitting in situ
on the coil, but only around two or three  kilohertz, I find on mine.
As Gary states it's best to learn doing them separately, first of all,
to avoid possible confusion.

Phil


and in real life, the resonant frequency of the secondary comes down from
the capacitive loading of the sparks, once it starts to break out.


_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla

_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla

_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla



_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla