William Beaty wrote:
On Sat, 20 Oct 2007, Jones Beene wrote:
I find Bill's T-coil comparison enlightening ;-) but lacking (in the
sense of apples-to-oranges) wrt to the latest experiment -- where there
is NO, ZERO, NADA, signal... merely ground, or DrS's touch.
Ah, that's different!
:)
I totally missed any announcement that self-acting or "closed-loop"
operation was achieved.
WHOA slow down, that's not what was said.
I've lost my sound again on this system so I can't hear the sound track
on Video 7 but I don't think it's vital to understand what's happening.
It's in three steps:
-- Apparatus shown unconnected, all LEDs dark.
-- ONE wire is connected, and the LEDs light. The wire is disconnected,
and the LEDs go out again.
-- Dr. Stiffler takes hold of the "input wire" with his hand, and the
LEDs light again, but dimmer this time than when a clip lead was
connected to the device. Is the signal generator still running in the
background at this time? I don't know; my /guess/ would be 'yes'.
(Darn I'd love to hear the sound track on #7 -- if someone types in a
capsule summary I'll be happy.)
At _no_ time is the circuit shown powering itself, nor is it shown
operating with no external connection. The fact that the external
connection is to Dr. Stiffler's hand in no way negates the fact that
there is an external connection.
******************************
ISSUE for Bill:
Tesla-coil type circuits tend to have high impedance, "looking back"
into the circuit, or so I have been led to believe. In contrast, LEDs
have (nearly) ZERO impedance when forward biased (they have a fixed
voltage drop, but no impedance on top of that). This is why they must
normally be driven by a current source, not a voltage source.
To answer a question put elsewhere, by someone (Jones, ?maybe?): No,
you can't light an LED with "voltage only" (high voltage and extremely
low current) -- you need an mA or two to light it, at somewhere between
1 and 3 volts depending on the particular LED. 3,000 volts from a high
impedance coil which can't source more than, say, 0.05 mA won't do the
job; the impedance mismatch is too large.
So how do you drive LEDs from a Tesla coil?
Did a video mention it? Or a message here? All I
saw was discussions of 12V power supply in early videos, but I didn't see
any announcement that the device started running by itself.
Nor did I. AFAIK it did not do that.
So that
explains all the uproar about scoffer sneers, and about needing a Faraday
shield.
No, that was earlier, back with video #4, which just used a two wire
hookup, but in which the output power was apparently far larger than the
input power.
Running by itself *IS* closing the loop.
But it doesn't do that.
