Recent content by Mike_In_Plano

The concept of "mutual inductance" means everything when analyzing this problem. At 25cm, the mutual inductance will be very low for small diameter coils. Even with large diameters, the mutual inductance is low. The circuit requires high primary currents typically with a parallel capacitance...

Brushed core-less and brush-less motors give the most bang per lb when you consider power and efficiency. Maxon motor and micro motor produce awesome core-less motors and can offer them with planetary gears.

Regarding the ancient technology for making precise settings - The Dekastat! http://www.tegam.com/pdf_files/calibration/resistors/ds1463_obs.pdf I'm so happy I could kiss a duck on the beak after finally rediscovering this technology

1. Look for anything that may arc, like motor brushes, and relays. brush arcing can be suppressed with line filters grounded with short, wide conductors to the motor body. Relays respond well to these products: http://www.cde.com/resources/catalogs/Q-QRL.pdf Or you can use zero-cross relays...

You can vary the thing and still get good results. i.e. the right leg has the same ratio as the left leg is good and sufficient. To see why the system works better with equal values, find di / dRtest (i in galvenometer) as a function of the values with one value, Rtest set. Then set di/dR to...

Most arcing occurs when the circuit is open. An MOV or RC snubber will eat the arc energy, improve relay life, and decrease glitches in the controller. You might try these guys: http://www.cde.com/resources/catalogs/Q-QRL.pdf Simply building an RC snubber is a bad idea because the resistor...

The concept of a 0V point was put forward by Dan White and consultants as a way of conceptualizing that when currents start flowing, points on the same ground system will likely have differing voltages due to the impedance between points and the development of voltage between points as a...

I don't know how ambient pressure will effect your ion count, but that circuit will be very sensitive to temperature... I don't perceive any means to trace your ion detector back to any measure of UV... I'd stick with a UV sensor or a UV pass filter with a piece of fluorescent material, and a...

This type of signal is an asymmetric pulse rather than sine wave. Essentially, you cannot have a "negative" amount of light. Peak-Peak measurements are more applicable. However, if your sensor's output reflects cable power, then the 10 log (Vout / Vnoise) reflects the signal to noise in terms...

A 24V, 300 W machine gives the same power as a 12V, 300W machine when each is running at rated speed, voltage, and current. Tying a 24V alternator into a 12V battery will allow it to charge at 1/2 of rated speed, but it will only deliver 1/2 of its rated power. The 24V machine has thinner wire...

Eeek! I made a mistake. Well, a lot of them, but the one in question regards the magnetic field calculator. It's at K&J magnetics. Sorry for any time I may have wasted...

This splits the topic into two more branches: We have the RF and low noise analog circuits, such as amplifiers, where wasted signal on the input reduces the signal-to-noise ratio. Thus a radio receiver is optimized to use as much of the signal as possible in the amplifying device (i.e...

Curiously, there is a semiconductor component that behaves like this, the DIAC. http://en.wikipedia.org/wiki/DIAC Unfortunately, it lakes the charming flash-flash-flash of the neon bulb.

Since I was a lad, I dreampt of building one of these for my grandfather. But, my studies have shown that you really do need quite a wind speed to produce the advertised power, and lesser speeds just produce dribbles of energy. Another frustration, and this is on the part of folks such as...

First, build everything to the left - No MOSFETS / transformer... Spend time with the resulting circuit until you are satisfied it's working. Then, add the MOSFETS with transformer, but no output rectifiers. Be careful as you explore this configuration as the mosfets are likely to be damaged...