| More Model Railway 
		projects: 
			
				| FLASHING 
				RAILROAD LIGHTS This circuit flashes two 
				red LEDs for a model railway crossing.
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			| TRAFFIC LIGHTS Here's a 
			clever circuit using two 555's to produce a set of traffic lights 
			for a model layout.
 The animation shows the lighting sequence and this follows the 
			Australian-standard. The red LED has an equal on-off period and when 
			it is off, the first 555 delivers power to the second 555. This 
			illuminates the Green LED and then the second 555 changes state to 
			turn off the Green LED and turn on the Orange LED for a short period 
			of time before the first 555 changes state to turn off the second 
			555 and turn on the red LED. A supply voltage of 9v to 12v is needed 
			because the second 555 receives a supply of about 2v less than rail. 
			This circuit also shows how to connect LEDs high and low to a 555 
			and also turn off the 555 by controlling the supply to pin 8.  
			Connecting the LEDs high and low to pin 3 will not work and since 
			pin 7 is in phase with pin 3, it can be used to advantage in this 
			design.
 
				Here is a 
			further description of how the circuit works:
					|  |  |  Both 555's are wired as oscillators in astable mode and will 
			oscillate ALL THE TIME when they are turned ON. But the second 555 
			is not turned on all the time!
 The first 555 turns on and the 100u is not charged. This makes 
			output pin 3 HIGH and the red LED is not illuminated.  However the 
			output feeds the second 555 and it turns on.
 Output pin 3 of the second 555  turns on the green LED and the 
			second 100u charges to 2/3 rail voltage and causes the 555 to change 
			states. The green LED goes off and the orange LED turns on.
 The second 100u starts to discharge, but the first 100u is charging 
			via a 100k and after the orange LED has been on for a short period 
			of time, the first 555 changes state and pin 3 goes LOW.
 This turns on the red LED and turns off the second 555.
 The first 100u starts to discharge via the 100k and eventually it 
			changes state to start the cycle again.
 The secret of the timing is the long cycle-time of the first 555 due 
			to the 100k and the short cycle due to the 47k on the second 555.
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			| 4 WAY TRAFFIC 
			LIGHTS This 
			circuit produces traffic 
			lights for a "4-way" intersection. The seemingly complex  wiring to 
			illuminate the lights is shown to be very simple.
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			| MODEL RAILWAY 
			TIME Here is a circuit that will 
				convert any clock mechanism into Model Railway Time.
 For those who enjoy model railways, the ultimate is to have a 
				fast clock to match the scale of the layout. This circuit will 
				appear to "make time fly" by turning the seconds hand once every 
				6 seconds. The timing can be adjusted by changing the 47k. The 
				electronics in the clock is disconnected from the coil and the 
				circuit drives the coil directly. The circuit takes a lot more 
				current than the original clock (1,000 times more) but this is 
				one way to do the job without a sophisticated chip.
 
 
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			| REVERSING A MOTOR-4
			(see 1, 2, 3 in 200 Transistor Circuits) In this example the power is 
			applied via the start switch and the train moves to the away limit 
			switch and stops. The 555 creates a delay of 1 minute and the train 
			moves to the home limit and stops. Turn the power on-off to restart 
			the action.
 
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