@Mags: re the light bulb on turn-on of amps: with this circuit you do not want a slow power up. It might not start oscillating, and that's the same situation as no loop: one mosfet stays on at very low Rds, and pop goes the mosfet. So put in a switch or relay and just flip that sucker on with the full supply voltage. If you ramp up the supply slowly, like for the very first test of the circuit, do it with an inline ammeter and if you see over 3 amps (no receivers) stop, you aren't oscillating. This does not mean it's not working, just that it needs that full 12v punch to wake up.

With no rx nearby the draw (12 v supply ) should be under 1 amp.

 Provided he makes and wins an argument about Buddhism with those who live there, any wandering monk can remain in a Zen temple. If he is defeated, he has to move on.
In a temple in the northern part of Japan two brother monks were dwelling together. The elder one was learned, but the younger one was stupid and had but one eye.
A wandering monk came and asked for lodging, properly challenging them to a debate about the sublime teachings. The elder brother, tired that day from much studying, told the younger one to take his place. "Go and request the dialogue in silence," he cautioned.
So the young monk and the stranger went to the shrine and sat down.
Shortly afterwards the traveller rose and went in to the elder brother and said:  "Your young brother is a wonderful fellow. He defeated me."
"Relate the dialogue to me," said the elder one.
"Well," explained the traveller, "first I held up one finger, representing Buddha, the enlightened one. So he held up two fingers, signifying Buddha and his teaching. I held up three fingers, representing Buddha, his teaching, and his followers, living the harmonious life. Then he shook his clenched fist in my face, indicating that all three come from one realisation. Thus he won and so I have no right to remain here." With this, the traveller left.
"Where is that fellow?" asked the younger one, running in to his elder brother.
"I understand you won the debate."
"Won nothing. I'm going to beat him up."
"Tell me the subject of the debate," asked the elder one.
"Why, the minute he saw me he held up one finger, insulting me by insinuating that I have only one eye. Since he was a stranger I thought I would be polite to him, so I held up two fingers, congratulating him that he has two eyes. Then the impolite wretch held up three fingers, suggesting that between us we only have three eyes. So I got mad and started to punch him, but he ran out and that ended it!"




As a thing is viewed, so it appears.

Quote from: TinselKoala on July 18, 2012, 12:31:42 AM
@Mags: re the light bulb on turn-on of amps: with this circuit you do not want a slow power up. It might not start oscillating, and that's the same situation as no loop: one mosfet stays on at very low Rds, and pop goes the mosfet. So put in a switch or relay and just flip that sucker on with the full supply voltage. If you ramp up the supply slowly, like for the very first test of the circuit, do it with an inline ammeter and if you see over 3 amps (no receivers) stop, you aren't oscillating. This does not mean it's not working, just that it needs that full 12v punch to wake up.

With no rx nearby the draw (12 v supply ) should be under 1 amp.

Na, I would fuse it. The light bulb was just a story, some may not know of it.
Thanks for the tips. Its good for everyone. ;]

The Tx could be 2 or 3 loops(turns), as long as the conductor length is followed? Smaller, more compact.

Mags

Quote from: Magluvin on July 18, 2012, 12:46:27 AM
Na, I would fuse it. The light bulb was just a story, some may not know of it.
Thanks for the tips. Its good for everyone. ;]

The Tx could be 2 or 3 loops(turns), as long as the conductor length is followed? Smaller, more compact.

Mags

I have not tried a multi turn Tx yet. I was gonna today but I ran out of round tuits.
The circuit is basically an induction furnace; maybe a multi turn coil will turn it into a tenpenny nail-melter.

The Hydraulic Analogy: Current and flow, voltage and pressure, wires and pipes.

OK, thanks for attending and welcome back, I hope you all had a good supper and a nice pipe or cigar after, as is your preference. Don't fall asleep too soon, though !

Now let's examine the Hydraulic Analogy for a bit.

Charge is fundamental, charge is conserved, charge is quantized, charge comes in two flavors, like charges repel and opposites attract, the negative unit charge is carried by the electron and is inseparable from it, positive charge is mostly the absence of electrons where they should be, except in things like proton beam accelerators and such like that there. And an enormous amount of charge, an entire Coulomb's worth, flows past your measuring point every second in a wire carrying one ampere of current.

So we don't really have any macroscopic experience with stuff that behaves just like that. How are we then to analogise QED so that it makes any kind of natural intuitive sense? We have to do the best we can, and it turns out that the Hydraulic Analogy (HA) does pretty good in some areas, and fails miserably in others, in this task of making electricity and charge understandable in the large.

Some electrical phenomena map pretty well to the HA. Others don't. Let's make good use of the ones that do, and step around the ones that don't, unless they carry important messages about what's been left out.

Water, of course, isn't quantized the way charge is (a single water molecule isn't really water), isn't fundamental, only comes in one flavor (if you're lucky) and doesn't mutually repel itself. But nevertheless it can be used to represent some very basic electrical parameters.

Pressure, and voltage. We've seen, using the Voltage Game, how a bunch of repulsive charge can result in a pressure that makes charge flow from a region of high pressure to one of lower pressure. It's pretty easy to see that water pressure or head is the analog of voltage.

Flow, and current. So if pressure is voltage, then flow must be current. Right? Well yes, but with caveats. Once again water isn't charge. Water has no "water field" that acts at a distance. Water doesn't repel like water. But most importantly, water flows at different velocities depending on pressure. Charge doesn't. The speed of charge in a wire is the speed of light, even though the speed of the charge carriers themselves is much slower. This is a great paradox, certainly, and of course my understanding is imperfect... Nevertheless it's an area where water and charge behave differently enough to screw up analogies.But to a first approximation, the flow of water is the analog to the current of charge that is electricity.

So, just like charge needs wires to flow in a complete circuit, so does water need pipes: pipes are the HA analog of conductors.

OK, so we can start building circuits now. We take a tank of water full to the top. We punch a pipe into the bottom of the tank, with a valve we can open or shut or regulate partway.  We put in a pump, since we are going to be pushing water up hill and must supply energy to do so. We put in another pipe and loop it back to the top of our tank. We now have a complete circuit and when we turn the pump on, flow will commence.

In fact we can combine the reservoir tank with an internal pump (powered by unspecified stored energy) and we have a battery analog. We can put in narrow sections of pipe... and we have resistors. We can put in remotely controlled valves for transistors. But the components I am most interested in analogising right now are capacitors and inductors. They present a bit more of a challenge for the HA than wires and switches, but these still can be met fairly well.

Let's take a quick break here and stretch, indulge your vices and flirt a bit. Come back later this evening please, for Capacitors and Inductors: The Hydraulic Analogs, and an introduction to fields of force.