Re: magnifier questions

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Original poster: "Dr. Resonance" <resonance@xxxxxxxxxx>


Use a sparkgap in which multiple sections are connected in series --- you
need a fast quench time. Usually 6-8 series connection sections will work
best.

Large dia. rotor so the ft/sec break speed is high.  24-30 inch dia. rotor
if possible.  Variable speed DC motor on RSG to adj as necessary.  The 2-3
HP DC treadmill motors work good for this.  Use a variac on them and rectify
output.  Also, use large filter cap on output of power supply to the motor.
Be sure to use a safety bleeder resistor across this cap.

Keep driver impedance low --- use copper tubing (100 turns with pri tapped
across first 10-12 turns) on large dia. coilform.

Driver coil should have inductance of 6-7 times the inductance of the
resonator coil.

Use 3.14 for h/d ratio of resonator coil (pi).

Resonator terminal capacitance 8-10 times dia. of resonator coilform dia.

If possible, match the impedance of the driver system to the base impedance
of the resonator coil.  In theory, this works best but in practice it's not
always possible.  Get as close as you can.

Dr. Resonance



And now my second project is building a relativ large magnifier and I´ve a
few questions.
The magnifier should operate at mode 2,3,6
first a few coil specs:
power level around 10-14kVA prim.cap 0.1µF-0.2µF
primary:
flat primary made from 2,4" wide copper sheet
10turns inner circle: 32,7" outer circle: 48,5"
driver:
31,85" diam. 250turns AWG.11-12
winding length is 34,6" (240t) and the last 10 turns are spaced 0,14" so
total 37". resistance around 4.7 ohms
inductance measured 31,5mH Cs=37pf foil isolated
extra coil:
12,59" diam.x 62" winding length 1075turns AWG17-18.(1.32mm)
measured 67.2mH Cs=25,5pf fres without topl.=122khz

I studied the Colorado Springs notes and simulated the
modes of Teslas second master oscillator.And my destination
was to have the same frequencies in an scaled down magnifier,
with some modern knowledgement.
now my questions:

How much topload should I use?
normally I would drop the resonator to around 70khz.

That´s around 50pf Ctop or a Toroid 44"x10" + shielding toroid.
The shielding toroid also has a small capacity which add to the top
terminal.
Another possible Toroid (for me,because i will use satellit-bowls as
support for the aluflex tubing) has the dimensions 60"x12" Ctop around
64pf+shielding toroid.
I´ve than read Ed wingates coil specs,and he uses a lot of
more Topload than my first toroid.
On the photos he always uses a small breakout point,
but i won´t use a break out point.

The second question:
The coupling:
I´ve calculated with magsim k=0.56.
With the flat primary i could only go to k=0.45
With optmag I simulate this and get a somewhat lower output voltage.
And the last question:
Will my magnifier work?
I know I ignored a few design rules.
(extra coil h/d ratio 5:1 / a lot of inductance in the driver)
best regards
Alex