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2 wire secondary



Subject: 
        2 wire secondary
  Date: 
        Sat, 12 Apr 1997 15:08:28 -0700
  From: 
        Gary Weaver <gweaver-at-earthlink-dot-net>
    To: 
        tesla-at-pupman-dot-com


I built a secondary coil using 2 wires side by side connected in
parallel. The wires are both #24 wound on a 4" PVC pipe 12"
long.  I have another coil wound with 1 wire #24 on a 4" PVC pipe 12"
long.  I tested the the performance of the 2 coils using
the same power supply, the same Richard Quick spark gap and the same .01
uf capacitor.

Primary is 1/4" copper tubing flat wound.  8 turns spaced 1/2" center to
center =.250 between the coils.  The inside diameter
is 5.5" and the outside diameter is 13.5". 

Secondary #1 is 532 turns of #24 wire 4.5" dia wound 11.5" long.  Ohms =
14.519  KHZ = 596.8  uh = 10679

Secondary #2 is 2 coils 266 turns each of #24 wire 4.5" dia wound 11.5"
long connected in parallel.   Ohms = 7.26 for one
coil divided by 2 = 3.63 for both coils.    KHZ = 1193.6 for 1 coil.  uh
= 2670 for 1 coil.

Test 1

Toroid 5"x9" on Sec. #1. Primary tap = turn 7. Output = thin blue 7"
sparks to a grounded sphere.

Toroid 5"x9" on Sec. #2. Primary tap = turn 1.75. Output = very white
hot 8.5" sparks to a grounded sphere.

Test2

Toroid 4.5"x16" on Sec #1. Primary doesn't have enough turns to tap. 
Output = 0"

Toroid 4.5"x16" on Sec #2. Primary tap = turn 3.25. Output = very white
hot 12.5" sparks to a grounded sphere.


A coil wound with #20 wire 4.5" dia. 11.5" long, ohms = 3.767, KHZ =
935.7, uh = 4344.  With toroid 4.5"x16" the primary
should tap about turn 4.5 unless I made a mistake in my calcualtions.  A
difference of 1.25 turns in test 2.

The main advantage I see using 2 wires in parallel is the smaller
primary coil.  Some of my primary coils are very large.  Also
larger toroids can be used. 

The 2 wire secondary coil output sparks are hotter and longer than the
coil wound with 1 wire.  2 #24 wires in parallel should
be about equal to a coil wound with #20 wire.


Gary Weaver     Experement 7927