From: "Barton B. Anderson"
Date: Sun, 19 May 2002 23:34:27 +0000
Subject: Re: [TSSP] Racing arcs
--Boundary_(ID_tpac39shIE2pbMGuGbGH6w) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT Hi Paul, Following is my primary data in fixed width font. NOTE: Inner turn of primary was incorrect previously. I was off by 0.375" (can't believe I did that, but I did. When I found that error, I realized why I made it and decided to get this primary down once and for all. Thus the following): Turn O.D. LuH 1 11.375 3 1.5 12.25 4 2 12.9375 5 2.5 13.8125 6 3 14.5625 7 3.5 15.375 9 4 16.125 11 4.5 16.875 13 5 17.5625 15 5.5 18.3125 17 6 19.0625 20 6.5 19.8125 24 7 20.4375 26 7.5 21.1875 31 8 21.9375 34 8.5 22.75 39 9 23.375 43 9.5 24.1875 49 10 24.9375 53 10.5 25.625 60 11 26.3125 64 11.5 27.125 73 12 27.875 77 12.5 28.6875 87 13 29.375 91 13.5 30.125 102 14 30.9375 107 14.5 31.625 119 15 32.375 125 15.3 32.875 137 Today I began the tuning process. I first measured the sec w/toroid in position = 69.7kHz. I used low power (transformer allowed only 100V in) and set up my strike rod about 4 feet from edge of toroid and parallel to toroid). I left the toroid at 77" as is. I started deep in at turn 10 and worked my way out. Even at the low voltage input, it is still no problem breaking out. However, to direct the streamers toward the strike rod, I placed a breakout point on the toroid. Here's the how it went. Turn 10: several brushy sparks. infrequent rod hits. no racing sparks. Turn 11: less brushy sparks. more rod hits. no racing sparks. Turn 12: 4 to 5 sparks. many rod hits. no racing sparks. Turn 13: 2 to 3 sparks. mostly rod hits. no racing sparks. Turn 14: same as above. Turn 15: 2 to 3 sparks. heavy rod hits but irratic. no racing sparks. Went back between turns 13 and 14 and began tuning within these turns. Best tune for sparklength was achieved at 13.5 turns and ended up with 1 to 2 sparks at a time. Note, with "low power" I never had a problem with racing sparks (I guess that would fit into the lastest theory as well). I removed the breakout point and ran the voltage up for some moderate power levels. The coil ran great, arcs were fierce, and no racing sparks. I didn't get a chance tonight to adjust coupling. Still to be done. But when I do this, I think I'll raise the primary as opposed to messing around with the secondary. I expect maybe a 1/4" change from present. I rescoped the coupled modes tonight after replacing a potentiometer with a setup of a cource multiturn pot and a fine multiturn pot for higher accuracy of the frequency. Took some time but worked out great. Anyway, here are the modes (kHz) measured (tap at 13.5): 60.1, 71.7, 237.9, 366. Can't give max spark lengths until I can get outside with the coil. Tonight, even with only 100V input, I hit 6 feet at times (up and over the strike rod), so it seems to be running pretty well. At best tune, the sparks had a huge curve to them (heading up and curving back down to the strike rod). I like your thought of setting up the six dimensions for each coil. That would really help organize the data and help out with what to test next. I was hoping to get enough time to take the system outside over a ground plane, but the weather didn't cooperate (windy, cloudy, periodic rain). Take care, Bart --Boundary_(ID_tpac39shIE2pbMGuGbGH6w) Content-type: text/html; charset=us-ascii Content-transfer-encoding: 7BIT Hi Paul,Following is my primary data in fixed width font. NOTE: Inner turn of primary was incorrect previously. I was off by 0.375" (can't believe I did that, but I did. When I found that error, I realized why I made it and decided to get this primary down once and for all. Thus the following):
Turn O.D. LuH
1 11.375 3
1.5 12.25 4
2 12.9375 5
2.5 13.8125 6
3 14.5625 7
3.5 15.375 9
4 16.125 11
4.5 16.875 13
5 17.5625 15
5.5 18.3125 17
6 19.0625 20
6.5 19.8125 24
7 20.4375 26
7.5 21.1875 31
8 21.9375 34
8.5 22.75 39
9 23.375 43
9.5 24.1875 49
10 24.9375 53
10.5 25.625 60
11 26.3125 64
11.5 27.125 73
12 27.875 77
12.5 28.6875 87
13 29.375 91
13.5 30.125 102
14 30.9375 107
14.5 31.625 119
15 32.375 125
15.3 32.875 137Today I began the tuning process. I first measured the sec w/toroid in position = 69.7kHz. I used low power (transformer allowed only 100V in) and set up my strike rod about 4 feet from edge of toroid and parallel to toroid). I left the toroid at 77" as is.
I started deep in at turn 10 and worked my way out. Even at the low voltage input, it is still no problem breaking out. However, to direct the streamers toward the strike rod, I placed a breakout point on the toroid. Here's the how it went.
Turn 10: several brushy sparks. infrequent rod hits. no racing sparks.
Turn 11: less brushy sparks. more rod hits. no racing sparks.
Turn 12: 4 to 5 sparks. many rod hits. no racing sparks.
Turn 13: 2 to 3 sparks. mostly rod hits. no racing sparks.
Turn 14: same as above.
Turn 15: 2 to 3 sparks. heavy rod hits but irratic. no racing sparks.Went back between turns 13 and 14 and began tuning within these turns. Best tune for sparklength was achieved at 13.5 turns and ended up with 1 to 2 sparks at a time.
Note, with "low power" I never had a problem with racing sparks (I guess that would fit into the lastest theory as well). I removed the breakout point and ran the voltage up for some moderate power levels. The coil ran great, arcs were fierce, and no racing sparks. I didn't get a chance tonight to adjust coupling. Still to be done. But when I do this, I think I'll raise the primary as opposed to messing around with the secondary. I expect maybe a 1/4" change from present.
I rescoped the coupled modes tonight after replacing a potentiometer with a setup of a cource multiturn pot and a fine multiturn pot for higher accuracy of the frequency. Took some time but worked out great. Anyway, here are the modes (kHz) measured (tap at 13.5):
60.1, 71.7, 237.9, 366.
Can't give max spark lengths until I can get outside with the coil. Tonight, even with only 100V input, I hit 6 feet at times (up and over the strike rod), so it seems to be running pretty well. At best tune, the sparks had a huge curve to them (heading up and curving back down to the strike rod).
I like your thought of setting up the six dimensions for each coil. That would really help organize the data and help out with what to test next. I was hoping to get enough time to take the system outside over a ground plane, but the weather didn't cooperate (windy, cloudy, periodic rain).
Take care,
Bart
--Boundary_(ID_tpac39shIE2pbMGuGbGH6w)--
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.