Delay Circuits

This switch allows the model train at such a station will automatically slow down. The train stands for a certain amount of time and then slowly pulls back. You do not own the train to stop. The relatively simple circuit works. P1 potentiometer for setting the waiting time, while turning to A caused a shorter waiting time and turn to B results in a longer waiting period. P2 is to set the brake and acceleratieweg. Here, too, turn to A results in faster acceleration and the train slows. ..

Delay switching for power amplifiers

Delay switching for power amplifiers

This delay can be used in power amplifiers, to prevent the fuses fail when the amplifier is turned on. The circuit is very simple with a relay which turned on when C2 and C3 are charged. If the relay has not been applied, the resistors used to control connected to feed. If after some time the relay attracts the bridge resistors. Watch out for your own safety when building this circuit. On the whole circuit is power. F1 should be the value of having the fuse that normally would be used...

Delaying Pulse from 555 circuit

Delaying Pulse from 555 circuit

The circuit below illustrates generating a single positive pulse which is delayed relative to the trigger input time. The circuit is similar to the one above but employs two stages so that both the pulse width and delay can be controlled. When the button is depressed, the output of the first stage will move up and remain near the supply voltage until the delay time has elapsed, which in this case is about 1 second. The second 555 stage will not respond to the rising voltage since it requires a negative, falling voltage at pin 2, and so the second stage output remains low and the relay remains de-energized. ..

Delay circuit with LM339

Delay circuit with LM339

In this circuit a LM339 quad voltage comparator is used to generate a time delay and control a high current output at low voltage. Approximatey 5 amps of current can be obtained using a couple fresh alkaline D batteries. Three of the comparators are wired in parallel to drive a medium power PNP transistor (2N2905 or similar) which in turn drives a high current NPN transistor (TIP35 or similar). The 4th comparator is used to generate a time delay after the normally closed switch is opened. ..

Power Off Delay Relay circuits

Power Off Delay Relay circuits

The two circuits below illustrate opening a relay contact a short time after the ignition or ligh switch is turned off. The capacitor is charged and the relay is closed when the voltage at the diode anode rises to +12 volts. The circuit on the left is a common collector or emitter follower and has the advantage of one less part since a resistor is not needed in series with the transistor base. However the voltage across the relay coil will be two diode drops less than the supply voltage, or about 11 volts for a 12.5 volt input. ..

Digital Countdown schematic with 555

Digital Countdown schematic with 555

This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with the output held high. When the switch is opened, the timer produces an approximate 1 second clock signal, decrementing the counter until the 0 count is reached. When the zero count is reached, the 'carry out' signal at pin 7 of the counter moves low, energizing the 12 volt relay and stopping the clock with a low signal on the reset line (pin 4). The relay will remain energized until the switch is again closed, resetting the counter to 9. The 1 second clock signal from the 555 timer can be adjusted slightly longer or shorter by increasing or decreasing the resistor value at pin 3 of the timer. ..

Long delay schematic with CD4040

Long delay schematic with CD4040

Generating long delays of several hours can be accomplished by using a low frequency oscillator and a binary counter as shown below. A single Schmitt Trigger inverter stage (1/6 of 74HC14) is used as a squarewave oscillator to produce a low frequency of about 0.5 Hertz. The 10K resistor in series with the input (pin 1) reduces the capacitor discharge current through the inverter input internal protection diodes if the circuit is suddenly disconnected from the supply. This resistor may not be needed but is a good idea to use. ..

AC time delay circuit with 555

AC time delay circuit with 555

Described timer to participate in the current circuit switch - bulb without any modification of existing pipelines. Connect the timer is in Figure 1 The time switch has only two outlets, which is connected in parallel to the button (Fig. 1a) or switch (Fig. 1b). If you use the button works as a classical staircase circuit switch. Connect a timer switch in parallel to the original, we will extend bulb shines as the time required to leave the room. Dimensions of the timer are so small that it can be installed into standard electrical box under the original power switch. The wiring does not need to change anything, there is no need nor any assistant conductor. The timer is triggered by voltage drop. Switch closes when the interrupt for a moment the power supply which can happen even when a storm or manipulations in the substation. In places where the network is "soft" power matters and executive appliances such as vacuum cleaner...

Delay circuit for a long time periods ( 4060 )

Delay circuit for a long time periods ( 4060 )

If you need a timer circuit, we go after the most proven 555th However, if the delays are longer, based on timing capacitor capacity is too large. In this case, a circuit of Figure 1 After pressing the button - reset circuit - starts multivibrator. ..

amplifier delay output relay

amplifier delay output relay

This is a simple circuit which I built to one of my audio amplifier projects to control the speaker output relay. The purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circuit is wait around 5 seconds ofter the power up until the spakers are switched to the amplfier output to avoid annoying "thump" sound from the speakers. Another feeature of this circuit is that is disconnects the speaker immdiatly when the power in the amplifier is cut off, so avoinding sometimes nasty sounds when you turn the equipments off...

Delayed start for mains equipment

Delayed start for mains equipment

The schematic requires few components, because the timer function has been incorporated by Nutchip. For once, from the start, made up of contacts of the relay RE1 connected to terminal M2. If we turn on an appliance at the end of time, we will use the relay contact is signed (normally open) and the COM contact (common). But if we are interested in off the load at the end of time we will use the pair of contacts COM and NC (normally closed). The relay RE1 is driven by Nutchip junction 4 of the transistor TR1, and is suitable for connecting devices up to 300-350W of power. For higher powers use a power relay out, as described below...

Delayed Power supply schematic

Delayed Power supply schematic

I had designed up an oscillator with a Power Output circuit. Problem was when power was applied to the entire circuit, the output of the Oscillator gave a Momentary Spike into the output circuit. Thus Driving it full on for a split second. This Circuit connected in the DC Supply to the Power amp, just gives a Tiny Delay. Not sure if it will be useful to others, But Thought I would post it anyway...

Delay switching for Loudspeaker

Delay switching for Loudspeaker

The supply of circuit becomes from a AC line in the J1. This voltage can be from a separate transformer 2X12V (the prices of materials that I give it is for 2X12V AC), from existing coil 12V in their M/T of power amplifier or if it cannot become somebody from the two, then from the coils of mainly supply final amplifier, adapting always the prices of resistances R1/2 and R3, proportionally the price of voltage that is supplied the amplifier, according to the law of Ohm and the fall of voltage that we want to achieve (R=V/i). The voltage that it should we have in point A, before the IC2, should is bigger than + 15V 200mA, the IC2 supplies all the relay and led. ..

Mains Delay Switch For Lambs and Motors

Mains Delay Switch For Lambs and Motors

A circuit that will find enough applications. Basically the designing became in order to exist delay in quench one or more lamps in a stairwell or in any other space exists this need. It can become use, for the control various motor or other appliances, what is connected in the contacts of J3. The activation command is given by exterior pressing switches connected parallel [Fig2]. Does not exist restriction in the number of these switches. The switches lead with a simple cable of three cables with small diameter, to the J1. Each switch is constituted by the pressing switch and Led that works constantly, facilitating to find the place of switch in dark spaces. If the switches are placed in exterior spaces, it will be supposed they are waterproof. ..

Very simple Delay circuit!

Very simple Delay circuit!

The two circuits di atas illustrate opening a relay contact a short time after the ignition or ligh switch is turned off. The capacitor is charged and the relay is closed when the voltage at the diode anode rises to 12 volts. The circuit on the left is a common collector or emitter follower and has the advantage of one less part since a resistor is not needed in series with the transistor base. However the voltage across the relay coil will be two diode drops less than the supply voltage, or about 11 volts for a 12.5 volt input...