Do you want to connect a traditional PC monitor on the VGA output of the MAC (Apple)? Yes you can. It is not the same connector, but this can be done with simple adaptation. No need to add the electronic components to this MAC VGA adapter. It’s just changing the connection between the cable and connectors.

The two connectors are D-Sub 15 points, but the next type of monitor is high density, with three rows of five points instead of two rows of eight and seven points for South-D 15 classic. Note that the vertical sync terminal is not used VertSync side monitor, only the horizontal sync HorzSync terminal is used. The latter receives the composite sync C. Sync from the MAC. The rest of the wiring does nothing special: the three terminals of the component video RGB (Red-Green-Blue, RGB for Red-Green-Blue) are in direct correspondence with their respective mass. Don’t know what the limits are Idx.

• The device is connected to the mains (230V in general) power button allows oscilloscope to turn on, which makes the lights on. (4).
• After a while, there are the spot of light on the display device (sufficient time to emitting cathode heated to a certain temperature and that there is emission of electrons).
• If after a few seconds, the point is still not visible, use horizontal alignment and vertical alignment as shown. (10, 11)
• Using the concentration (or focus) (acting on the anode concentration) brightness (which works on the accelerator anode) controls the sharpness of the spot. (5 and 6)
• The point should not stay too long concentrated at one point: this will end the damage to phosphor screen, with the knob adjust the time base (or sweep time) (9) (which works on the horizontal deflection plates), printed on-site more or less rapidly: at low speeds, we see a spot to move on the screen, if the scanning speed increases, we can see the solid line called the traces.

Viewing the voltage

• Select an entry (called channels) or B (1 and 2)
• Choose direct coupling (coupling ( switch position)
• Set the sensitivity in V / cm or mV / cm on the selected channel, depending on the voltage display. (7 and
• Set the circuit by connecting the instrument ground.
•  Set the time base so that it appears on the screen, the number of periods desired. (9)
• If the curve is not stable, adjust the time by working on the Level “button trigger.
• Perform the setting horizontal alignment and vertical alignment.

Featuring two voltages

The units have a two probe input channel YA and YB: they allow you to see the two voltages.

• Select the two-way “A and B”
• Select the sensitivity (7) and (8) in accordance with the voltage to display.
• Make connections to the oscilloscope.
• The mass is common in cases where it is located between the two terminals which have dipoles will see the voltages, it is necessary to reverse the voltage YB acting on the button “B +”.

Based on the book “Gather yourself” no. 2, 2004.

Synthesizer assembly
Before assembling the board review the recommendations that are given at the beginning of this book. To avoid failure, try to observe generally accepted rules of assembly. List of components within the set of NM5101, presented below :

Parts List of NM5101 set

In accordance with Fig. 3 install and weld components on the board. DA1 chip is installed in accordance with Fig. 4 ( Synthesizer lighting effects part 3 ).
After installation check the quality of the ration and proper installation elements. Recheck charge for lack of short-circuits and breaks tracks.

This device would be interesting for students: introduction to the basics of electronics, allowing you to experience the assembly and adjustment of modern electronic devices. Synthesizer will be used for fan of light effects as a festive illumination, or a tutorial on microprocessor technology and programming.
This device requires a voltage 9-25V and current around 50mA.

Description of this Synthesizer

Fig. 1 and Fig. 2 on the Synthesizer lighting effects part 2 shows the assembly of synthesizer boards and electric circuit.

Synthesizer is based on a microcontroller from Atmel (DD1). Power supply of the microcontroller obtained from the IC regulator DA1.
Elements of CI, C2, ZQ1 set the operating frequency of the internal oscillator of the microcontroller. Resistors R1 … R6, R8 – used for current limiting. SW1 button is a consistent choice of animated images. The basic version of the proposed microcontroller 12 stitched images.

DC to DC converter circuit is an electronic circuit which can be used either to transform one voltage to different level/value; or to provide an isolation barrier for a voltage bus. DC to DC converters are typically being used in power distribution system to provide a local voltage conversion, point of load voltage regulation or power bus isolation.

Download the document of: Theory of Operation for DC/DC converter
» Download Link

My own specifications for my prototype are X= 36cm, Y= 5.5cm. This imparted a quite high pitch tone but I prefer it.

The X and Y dimensions should be played with to generate the exact tone your seeking, also I chose a telephone speaker along with a crystal mic so I got the funkiest tone I could think of. A dynamic mic would limit the treble somewhat most likely make it sound less harsh. I’d be thinking about any mods made to this design (ie. stories, suggestions, etc.) so really feel free to e mail me.

The amps could be any old common op-amp construction that could drive a speaker or take a microphone input.I just made use of some surplus material I’d lying around to build mine. The finished object had all the circuitry inside the tube and the power supply on the outside, with one control for the gain of the speaker (microphone was at fixed gain).

Note, if you locate this in front of the amplifier and turn every thing up, without adding any dampening towards the pipe, it is going to feedback just like you won’t imagine! You’ll most likely wish to avoid this because it tends to hurt your ears. I put a bit of foam rubber in one end of the pipe and an old sock in the other to dampen feedback. I like to leave my alternatives open though, so I also didn’t make this a permanent addition. My prototype is essentially a fuzz, as my guitar will overload the speaker quite easily and the tube just adds a bit of strange overtone and what I swear will be the smallest hint of reverb. Sounds wonderful though! Clean tones by way of a related set up would sound good too, but I haven’t constructed one of those yet. Perhaps a larger speaker (4-5″) and an old carpet pipe would probably add better characteristics for clean tones. Try altering the tube material also for a different tone, I almost used a little bit of gutter piping when I first made this, right now I wonder what it would’ve sounded like.

Download the Pipe Bomb Microphone construction in PDF file:
» Download Link

• Voltmeters measure voltage.
• Voltage is measured in volts, V.
• Voltmeters are connected in parallel across components.
• Voltmeters possess a extremely higher resistance.

Connecting a voltmeter in parallel

Measuring voltage at a stage
When testing circuits you often have to find the voltages at numerous factors, for instance the voltage at pin 2 of a 555 timer chip. This can seem complicated – where should you connect the second voltmeter lead?

• Connect the black ( damaging -) voltmeter lead to 0V, normally the negative terminal of the battery or power provide.
• Connect the red ( constructive +) voltmeter lead to the point you exactly where you need to measure the voltage.
• The black lead can be left completely connected to 0V whilst you use the red lead as a probe to measure voltages at numerous factors.
• You may wish to make use of a crocodile clip around the black lead to maintain it in location.

Voltage at a stage truly means the voltage difference in between that stage and 0V (zero volts) that is normally the damaging terminal of the battery or energy provide. Generally 0V will probably be labelled on the circuit diagram as being a reminder.

Analogue meters get a little energy from your circuit under check to run their pointer. This might upset the circuit and give an incorrect studying. To prevent this voltmeters should possess a resistance of at least 10 occasions the circuit resistance ( get this to become the highest resistor worth near exactly where the meter is linked).

Most analogue voltmeters utilized in school science are not appropriate for electronics simply because their resistance is too very low, usually a couple of k. 100k or even more is required for most electronics circuits.

Wiring diagram:

You should look is the color of wires on the wiring diagram, if reversed in the installation of the cable then there will be a short circuit.

Picture above is the wiring diagram for single pole light switch. For the installation of one light that can be controlled from multiple locations, please visit this page.

This article will teach you how to check measure a diode. This is a basic knowledge for students and electronic hobbysts. If your project is failed or your electronic device is broken, then you need to check the components. And before you check the components, you need to learn how to check and measure the components. Here is the explanation about how to check the diode:

________________________

Being able to determine the polarity (cathode versus anode) and basic functionality of a diode is a very important skill for the electronics hobbyist or technician to have. Since we know that a diode is essentially nothing more than a one-way valve for electricity, it makes sense we should be able to verify its one-way nature using a DC (battery-powered) ohmmeter as in Figure below. Connected one way across the diode, the meter should show a very low resistance at (a). Connected the other way across the diode, it should show a very high resistance at (b) (“OL” on some digital meter models).

Determination of diode polarity: (a) Low resistance indicates forward bias, black lead is cathode and red lead anode (for most meters) (b) Reversing leads shows high resistance indicating reverse bias.

Of course, to determine which end of the diode is the cathode and which is the anode, you must know with certainty which test lead of the meter is positive (+) and which is negative (-) when set to the “resistance” or “Ω” function. With most digital multimeters I’ve seen, the red lead becomes positive and the black lead negative when set to measure resistance, in accordance with standard electronics color-code convention. However, this is not guaranteed for all meters. Many analog multimeters, for example, actually make their black leads positive (+) and their red leads negative (-) when switched to the “resistance” function, because it is easier to manufacture it that way!

One problem with using an ohmmeter to check a diode is that the readings obtained only have qualitative value, not quantitative. In other words, an ohmmeter only tells you which way the diode conducts; the low-value resistance indication obtained while conducting is useless. If an ohmmeter shows a value of “1.73 ohms” while forward-biasing a diode, that figure of 1.73 Ω doesn’t represent any real-world quantity useful to us as technicians or circuit designers. It neither represents the forward voltage drop nor any “bulk” resistance in the semiconductor material of the diode itself, but rather is a figure dependent upon both quantities and will vary substantially with the particular ohmmeter used to take the reading.

For this reason, some digital multimeter manufacturers equip their meters with a special “diode check” function which displays the actual forward voltage drop of the diode in volts, rather than a “resistance” figure in ohms. These meters work by forcing a small current through the diode and measuring the voltage dropped between the two test leads. (Figure below)

Meter with a “Diode check” function displays the forward voltage drop of 0.548 volts instead of a low resistance.

The forward voltage reading obtained with such a meter will typically be less than the “normal” drop of 0.7 volts for silicon and 0.3 volts for germanium, because the current provided by the meter is of trivial proportions. If a multimeter with diode-check function isn’t available, or you would like to measure a diode’s forward voltage drop at some non-trivial current, the circuit of Figure below may be constructed using a battery, resistor, and voltmeter

Measuring forward voltage of a diode without“diode check” meter function: (a) Schematic diagram. (b) Pictorial diagram.

Connecting the diode backwards to this testing circuit will simply result in the voltmeter indicating the full voltage of the battery.

If this circuit were designed to provide a constant or nearly constant current through the diode despite changes in forward voltage drop, it could be used as the basis of a temperature-measurement instrument, the voltage measured across the diode being inversely proportional to diode junction temperature. Of course, diode current should be kept to a minimum to avoid self-heating (the diode dissipating substantial amounts of heat energy), which would interfere with temperature measurement.

Beware that some digital multimeters equipped with a “diode check” function may output a very low test voltage (less than 0.3 volts) when set to the regular “resistance” (Ω) function: too low to fully collapse the depletion region of a PN junction. The philosophy here is that the “diode check” function is to be used for testing semiconductor devices, and the “resistance” function for anything else. By using a very low test voltage to measure resistance, it is easier for a technician to measure the resistance of non-semiconductor components connected to semiconductor components, since the semiconductor component junctions will not become forward-biased with such low voltages.

Consider the example of a resistor and diode connected in parallel, soldered in place on a printed circuit board (PCB). Normally, one would have to unsolder the resistor from the circuit (disconnect it from all other components) before measuring its resistance, otherwise any parallel-connected components would affect the reading obtained. When using a multimeter which outputs a very low test voltage to the probes in the “resistance” function mode, the diode’s PN junction will not have enough voltage impressed across it to become forward-biased, and will only pass negligible current. Consequently, the meter “sees” the diode as an open (no continuity), and only registers the resistor’s resistance. (Figure below)

Ohmmeter equipped with a low test voltage (<0.7 V) does not see diodes allowing it to measure parallel resistors.

If such an ohmmeter were used to test a diode, it would indicate a very high resistance (many mega-ohms) even if connected to the diode in the “correct” (forward-biased) direction. (Figure below)

Ohmmeter equipped with a low test voltage, too low to forward bias diodes, does not see diodes.

Reverse voltage strength of a diode is not as easily tested, because exceeding a normal diode’s PIV usually results in destruction of the diode. Special types of diodes, though, which are designed to “break down” in reverse-bias mode without damage (called zener diodes), which are tested with the same voltage source / resistor / voltmeter circuit, provided that the voltage source is of high enough value to force the diode into its breakdown region. More on this subject in a later section of this chapter.

• REVIEW:
• An ohmmeter may be used to qualitatively check diode function. There should be low resistance measured one way and very high resistance measured the other way. When using an ohmmeter for this purpose, be sure you know which test lead is positive and which is negative! The actual polarity may not follow the colors of the leads as you might expect, depending on the particular design of meter.
• Some multimeters provide a “diode check” function that displays the actual forward voltage of the diode when its conducting current. Such meters typically indicate a slightly lower forward voltage than what is “nominal” for a diode, due to the very small amount of current used during the check.

__________________

The original article how to check and measure the diode using digital multimeter can be found on allaboutcircuits.com.