How to build a 3amp-min Circuit.

[xszaui]

Hi,

I am trying to build a 3 amp-min circuit and measure the magnetic field generated along the wire, but having problems figuring out how to build a stable circuit.

I have a:

DC power supply (150V 3amp),
insulated copper wire
rehostat (Which I think I have a wrong one as it glows red hot when placed in the circuit, and was beginning to smell).

Any links and tips on what I could do to generate a magnetic field around 50V/3amp would be great. The above is just the setup I am imagining which may be far off. (It's maybe the most inexpensive or maybe there is a better option).

Help is most appreciated.

Thanks,

Zaui

 

[Integral]

To get 3A from a 150V source, you must 50 Ohms resistance in the circuit. You did not say what gauge of wire, or how long your wire is.

for a 50 Ohms resistance you need about 50,000ft of 10ga copper (this is according to my CRC handbook of Chem & Physics)

If you are using 20ga wire it is down to 5000ft.

So how much wire do you have and what gauge is it?

 

[berkeman]

And that 50 Ohm power resistor will dissipate 450 watts. This experiment sounds a bit ill-conceived, xszaui. Can you please post more details about exactly what you are trying to do, so that we can help you design the experiment to be safe and achieve your goals?

 

[xszaui]

More details

Hi,

I am trying to build an exploded version of a quartz oscillator.

Pictures of something similar can be found at:
http://en.wikipedia.org/wiki/Crystal_oscillator"

However, commercial versions are always magnetically shielded or coated with metal which distorts the field making it near impossible to measure the magnetic field.

The voltage I would like to apply is 50V and 3 amp-min of DC current. The resonant output of the quartz oscillator should produce a magnetic field ('if I understand the articles correctly').

I don't know if I need to have a very thin sheet of quartz or there is a way to make a whole uncut crystal resonate. This is my first time working with piezo electrics and I'm pretty new to building circuits in general.

Help would be most appreciated.

Thanks

Zaui

 

[berkeman]

Hi,

I am trying to build an exploded version of a quartz oscillator.

Pictures of something similar can be found at:
http://en.wikipedia.org/wiki/Crystal_oscillator"

However, commercial versions are always magnetically shielded or coated with metal which distorts the field making it near impossible to measure the magnetic field.

No. They are hermetically sealed for a different reason -- long-term stability of the oscillation frequency.

The voltage I would like to apply is 50V and 3 amp-min of DC current. The resonant output of the quartz oscillator should produce a magnetic field ('if I understand the articles correctly').

No. There is no significant magnetic field involved in quartz crystal oscillators.

And you sure as heck don't need 50V and 3A to run a crystal oscillator. Crystal oscillators are low-power, low-voltage circuits that are used to provide a stable timebase. If you want high power oscillations, you start with a low-power crystal oscillator circuit, and then amplify the voltage waveform output from the oscillator. You don't try to build a 150W crystal oscillator.