Re: More Coupling...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jon Rosenstiel by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jonr-at-pacbell-dot-net>


Subject: Re: More Coupling...


> Original poster: "Barton B. Anderson by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>
>
> Hi Paul and Everyone,
>
> My reply here is to ask (plead) for more coiers to make coupling
measurements.
> All that is needed is a DMM capable of volt and amp readings (or meters
capable
> of this). Also needed is a primary that can be moved above and below the
> secondary base line in steps (or the secondary to achieve the same
result).
> Measurement is easy (we can define that later).

<snip>

Hi,

Just finished performing coupling measurements on my new small coil. I used
Terrys method, (applying a heavy current, (11.5A with my heater),  to the
primary and measuring the secondary voltage. (With a 10k resistor and a 1uF
capacitor across the secondary).

My coil is as follows:
Secondary OD=4.2"
Secondary winding length=24.5"
Secondary wire size=28
Secondary measured inductance=56mH

Primary ID=7.2"
Primary wire dia=0.1875"
Wire spacing=0.25", (0.4375" center to center)
Total turns=21
Tap position=17.25
Measured inductance=0.1131mH, (at 17.25 tap)

Secondary elevation           K
-0.375"                               0.110
0                                         0.103
0.25"                                  0.099
0.5"                                    0.095
0.75"                                  0.091
1.0"                                    0.087
1.25"                                  0.083
1.5"                                    0.079
1.75"                                  0.075
2.0"                                    0.072
2.25"                                  0.068
2.5"                                    0.065
2.75"                                  0.062

Hope this is useful,

Jon