[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Beginner Q's
- To: tesla@xxxxxxxxxx
- Subject: Re: Beginner Q's
- From: "Tesla list" <tesla@xxxxxxxxxx>
- Date: Fri, 18 Nov 2005 11:40:42 -0700
- Delivered-to: testla@pupman.com
- Delivered-to: tesla@pupman.com
- Old-return-path: <vardin@twfpowerelectronics.com>
- Resent-date: Fri, 18 Nov 2005 11:44:41 -0700 (MST)
- Resent-from: tesla@xxxxxxxxxx
- Resent-message-id: <qJMesB.A.QV.WEifDB@poodle>
- Resent-sender: tesla-request@xxxxxxxxxx
Original poster: "D.C. Cox" <resonance@xxxxxxxxxx>
With only a 30 mA drive xmfr and a 3.5 inch coil don't use 24
AWG. You need more turns --- around 1,200 to 1,400 on the sec coil
with an aspect (winding) ratio of 4.5:1. Using only 600 turns will
drastically cut your output performance down. A 4 inch dia. ID PVC
water pipe sanded down inside and out, coated inside and out, then
wound will work good with this size xmfr. We use 30 AWG on our
secondaries with this size xmfr. You could get away with 28 AWG but
don't want to go smaller or output is reduced.
Use a .008 uF (8 nF) tank capacitor value --- easy to make up with
MMCs and a lot better than rolling your own from a space savings
standpoint. This will keep your xmfr from trying to resonate with
the cap. Also, be sure to use a Terry filter on the xmfr.
Using MMC caps also allows you to keep your coil base small which
makes the spark look larger. A very large base with a small spark
has an illusion of making the spark look even smaller.
Dr. Resonance
Ok I think I need some education!
If you will permit me I would like to post the
calcs for the coil I am trying to build.
I understand some of what it means but I am an
electrician not an engineer. Any pointers or
information on this design would greatly help!!
'Flea
POWER SUPPLY
Allanson Luminous Tube Transformer 120v input
15kv
output
30ma
450VA
General Electric Volt-Pac Variable Transformer 120v input
120
- 140v output
7.5A
SECONDARY COIL
Outer
Diameter
3.5 inches
Coil
Length
14 inches
Aspect
Ratio
1:4
Turns
651.1628N
Windings
#24 Gauge Magnet Wire
Wire
Length
596.3566 feet
Resonant
Frequency 680.287 KHz
RF
Resistance
249.68 12 Ohms
XL @
Resonance
35618.78 Ohms
Max Unloaded Q @ Resonance 142.657
Inductance
8.337334mH
Distributed / Stray
Capacitance 6.572969pF
Approximate Loaded
Q 50.94893
Terminal
Capacity
6.572969pF
Resonant Frequency Drop
to 480.963 KHz
TRANSFORMER / CAPACITOR MATCHING
Max Primary
Capacitance .0038 microfarads
Minimum Voltage
Rating 37500 Volts
SPARK GAP
Type
Static
Number of
Gaps 8
Gap
Spacing
.010 - .020 inches
TANK CAPACITOR
Type
Rolled
Plate
Thickness
Aluminum Roof Flashing
Dielectric
; .040 Inches (40 mils) Polypropylene
Plate
Length
60 Inches
Plate
Width
14 Inches
Capacitance per
Roll
.019 microfarads
Voltage per
Roll 8000v
Rolls Required (Series Connected) 5
Final
Capacitance
.0038 microfarads
Maximum Transformer
Capacitance .0038 microfarads
Final Volt age
Value 40kV
PRIMARY COIL
< B style="mso-bidi-font-weight: normal">
Inductance Needed for
Resonance 14.4microhenries
Type
Flat Spiral
Conductor
.24" (1/4") copper tube - .3725" (5/16") OD
Number of
Turns 8N
Spiral
OD
14.75" (14-3/4")
Spiral
ID
5.375" (5-3/8")
Turns
Spacing
.3125" (5/16")
Approximate Tap
Point Turn 7-8
TOPLOAD (TOROID)
TOROID 1
Torus
Size
1" X 6"
Torus
Capacitance
5.10 pF - This to match secondary terminal capacity
Suggested
Diameter 2" - 4"
Suggested Power
Level 200W - 400W
TOROID 2
Torus
Size
2" X 8"
Torus
Capacitance
6.80 pF - This to match secondary terminal capacity
Suggested
Diameter 3" - 5"
Suggested Power
Level 400W - 800W