T&L Publications

I suspect that the term "magnet wire" refers to one of the earlier uses of this type of wire, winding electromagnets. In general, magnet wire is solid wire with the insulation applied as a thin film (a few thousandths of an inch). This allows a maximum amount of copper in a given cross sec...

The indicator sounds like a style of gas gauge that was used on old cars (possibly before WW II). The position of the needle depends on the ratio of the currents in the two coils and not on the magnitude of the currents. This is a superior arrangement to the hot wire indicators which followed them. ...

The oscilloscope will not indicate VSWR. It is shown connected to the output of a detector connected to the output of the slotted line. It may show a square wave if the signal source is modulated with a square wave, but this is not indicated in the drawing. The test setup shown can be used to measur...

Motors that are designed as capacitor run motors (as opposed to capacitor start motors) often have two identical windings that are desigend to be excited 90 degrees ot of phase. One winding is connected directly to the power source and the other winding is fed through a series capacitor. Often only ...

In general, the run capacitor is the more rugged part. Both types of capacitor perform the same function. They provide a voltage that is shifted in phase from the AC power line. Some motors run on a single phase. These motors have to be started as a two phase motor, single a single phase winding doe...

Some attention should be paid to power ratings here. When a motor is stalled, the stall current is simply the applied voltage divided by the armature resistance. Even small motors can have stall currents in the ampere range. Either the motor controller has to be able to withstand the maximum stall c...

You might consider using a CPLD instead of a microcontroller for this type of application. These consist of a number of cells, each of which has a cluster of logic gates and a flip-flop. They are programmed by software using a schmatic diagram of the logic desired as the input. Counters and timing c...

Wikipedia isn't 100 percent reliable, and this is probably an example. The Royer converter is a push-pull oscillator that uses magnetic saturation of a transformer or inductor to determine the frequncy of oscillation. In the simplest form, a single transformer has primary, secondary, and feedback wi...

The Royer circuit produces a square wave output. The switching transistors are saturated, so the voltage drop can be reduced below about half a volt without much difficulty. With a 12 volt supply, the off collector will go up to about 23.5 volts. A normal rectifier will drop this by about 1 volt, so...

Most op amps are compensated by using one dominant pole, which is set at a much lower frequency than the remaining poles. In the case of the uA741, this pole was in the 10 Hz region. This pole is usually created by a capacitor made using the metal and silicon oxide layers (usually less than 10 pF). ...

One form of voltage doubler is simply a Royer type of inverter with diodes connected from the transistor collectors to the output. Thje Royer converter is a push-pull transformer coupled circuit. The primary winding on the transformer acts as an autotransformer, resulting in a voltage of twice the s...

There will be a pole for each transistor and possibly others due to stray capacitances. The NPN stage is a common base stage from a feedback point of view. The pole for this transistor will be in the neighborhood of the Ft of the transistor (probably slightly lower). This might be in the 100 to 200 ...

I would suggest two solar cells, mounted back to back. Take the difference between the two photocurrents. This can be done by connecting the solar cells in parallel with one reversed with respect to the other (plus of first cell to minus of second cell; minus of first cell to plus of second cell. Co...

You might be able to use a silicon photodiode or solar cell to get an estimate of the light output. A silicon photodiode usually has a scale factor of .4 to .6 amperes per watt at its peak wavelength (usually near 900 nanometers). The graph of spectral response can be used to correct this for the LE...

I assume that you are talking about the device shown in Pat. No. US 6,460,540. This appears to use an inflatable cuff to trap liquid moving down the trachea and providing a tube for sucking out the trapped liquid. The top of the cuff appears to be an area that would be difficult to drain entirely an...