Recent content by sophiecentaur

A trucker in a cafe may not be the best source of this kind of information. Even nice blokes can talk BS about EE. There's a principle that says appropriate fuses should be in any circuit. Plug an electric kettle into an extended lighting circuit and no one dies; they just don't get their cup...

I reckon that, on a humid day, the leaves / twigs could be steaming (if you look closely). There are many sites that describe the OP's idea but the only one I found that 'really worked' was this one which used 127 one foot square mirrors with a wooden target at unspecified distance. This is an...

If this is to be used for several hours, how does the angular range work? But what about the image size at the focus on the tree? You have even less than 1kW of incident power and an image size of say 4cm diameter. What sort of temperature will that produce? Fine for boiling water but what...

Did you actually make it work? What was the size and focal lengths of the added elements and how big was the image of the Sun at the final focus? It seems to me that the arrangement in the diagram is the equivalent of a single mirror with a focal length of the original 150 ft.

I'd like to know if it will make that rumbling noise all the ones on films make. And they're always there when the people look up, too. I reckon overhead with twelve hours to impact would be comforting. But NIMBY.

A linear array will have similar directivity normal and 'horizontal"' to a 2D array pattern in one plane but its gain could be much lower. The OP doesn't want to tell us any details - or he has none available. As you say (and I already said) we need to know some context. Maybe he's trying to...

Many people want to "do it this way" because "this way" is appealing. A successful engineer defines the job and the priorities first and then finds the best way to achieve that. Toolshops make their profits by selling flashy gear that may only be used once by the customer who couldn't actually...

I went back to this, from the original post and I would like to know how directivity can be achieved - or if it is relevant here. What frequency would you be operating at? It may be relevant. Equal lengths of feeder from the elements will produce in-phase result for broadside conditions - OK...

That would work in some circumstances but induced volts (or currents) from interfering sources could upset that idea. The normal form of connecting signals is an 'unbalanced' line with signal and earth wires. That would not be possible in your suggestion. But we really don't know enough about...

Arrays of piezo sensors can be designed to have a sensitivity pattern in just the same way as an RF array. It's a matter of the impedances of the sources and the impedance of the amplifier. An appropriate "summer circuit" will add the currents from all the sensors if the sensors have a high...

My last house had an overhead supply and T-T earthing. Nobody died so nothing was "really wrong". There are obviously a range of opinions about this and I won't lose too much sleep over it, whatever the outcome. But it annoys / worries me that my house (and everyone around me) may be served by...

We are in different worlds and I need some advice which applies to a particular practical situation in UK. I appreciate your input because of your high level technical knowledge but I need specific advice about what is approved over here in UK and how much I may have to pay. This whole issue...

That statement includes the word "misconception" and I agree with that in some circumstances. Many faults are not just a simple 'short circuit' though. I'm used to fused plugs which prevent excessive current through an appliance. But even they will not blow when in series with a typical T-T...

Hardly a straw man argument. I could ask you if you had the opportunity to change from a TN-S system to T-T would you change? What would be a good reason? T-T is a last resort when there is no low resistance company earth supplied? I notice you write from US which is often a different electrical...

There are many accepted practices in the past which are not acceptable now. It's only cost that affects that. The presentEarth Loop resistance is 130Ω which is in spec. But that is not inherently safe because it relies on active protection. The standards for T-T earthing are surely only there...