Re: Request for help with air core transformer/power transfer system

["Tesla list" <tesla@xxxxxxxxxx>]

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


You would need some type of magnetic core on both sides of the glass if you
operate at 60 Hz.  To do it without a mag. core would require a high freq.
current.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Monday, December 06, 2004 10:00 PM
Subject: OT: Request for help with air core transformer/power transfer
system


> Original poster: David Speck <dave@xxxxxxxxxxxxxxxx>
>
> List,
> I know this isn't directly TC related, but I hoped someone with more
> transformer theory experience that I have might lend a hand, with Terry's
> indulgence.  Please feel free to respond privately.
>
> ->Sound enough like electricity transmission without wires ;o))  But
> respond direct if not really related to Tesla coils) - T. <-
>
> I'd like to transmit about 6 volts AC at 60 Hz and 250 mA through a glass
> plate about 1/4" thick without drilling a hole in the glass, and without
> making any really esoteric circuitry like a high frequency drive
> circuit.  I don't have a lot of time for experimentation, so I though I'd
> run my idea past you and see what you thought.
>
> I have space to put a 4 1/2" OD flat circular pancake coil (about 1/4"
> thick) on each side of the glass.  I figured I'd run 6 volts from a wall
> wart into the primary, and have a matching secondary directly opposite it,
> on the other side of the glass, from which I'd feed a diode bridge and
> filter cap on the secondary side..  I know similar arrangements are used
to
> recharge batteries of implanted medical devices, but I don't know if they
> work at 60 Hz or higher frequencies.  My main concern is making an
> arrangement that will not burst into flames during prolonged unattended
> operation.
> Questions are:  Would it be better to have primary and secondary circuits
> with a relative few turns of heavier wire, or lots ot turns of finer
> wire.  I expect that you'd get more inductance, but more resistive heating
> with finer wire, but in the absence of an iron core to corral the magnetic
> flux, I worry about drawing too much current from the wall wart into the
> primary with a few turns of thicker wire.
> Is there a way to calculate the optimum number of turns and wire size for
> this arrangement?
>
> Is there any simple arrangement of soft iron wire or sheet that would help
> to constrain/direct the magnetic flux for better energy transfer without
> involved magnetic core fabrication?
>
> Thanks in advance for your thoughts.
>
> Dave
>
>
>
>