One of my first projects, this uses old school timers and counters. Most IC's require some clean power so we have a 12 volt regulator from aircraft power with a couple of caps as noise and ripple filters. .01 ufd capacitors are connected as close as possible to vdd on the 4017 chips to keep out noise and make them more stable. The effect I wanted was a multi-flash strobe that toggled from side to side. To accomplish this, two CD4017 decade counters are used  1ea per side. Each IC requires a clock to function. The clock speed chosen is the rate at which you want to flash your light. I used a 556 timer to provide this clock as well as another clock to set the toggle rate from one side to the other. The other 555 timer is hooked up as inverter. Any inverter chip will do here. I happened to have a number of 555's on hand. is all. When the reset on one 4017 is high, the other will be low.One chip enabled, the other chip disabled. This provides the toggle from side to side effect. The diodes on the outputs are steering diodes. When the Q1 port goes high, the diode is forward biased and a high appears on the gate of the FET. At the same time, the steering diode on the Q3 port is reversed biased and prevents the pulse from re-entering the ic. The FET is configured as a switch. I like to use FET's because they handle a lot of current and the high impedance input does not load the circuit. The anode side of the strobe led is connected to aircraft power. The cathode side is connected through the FET to ground. When the FET is turned on, the ground is supplied to the strobe and it will light. It only lights for the duration that the fet is pulsed on.  The pulses are very short duration so I don't have any current limiting on the stobe leds. This allows the current to come up very quickly. A high power high current led should be used here. I use these. When breadboarding this circuit, monitor the current on your strobe line to make sure you don't over drive the leds. The optional panel leds are redundent. I thought they might be distracting so I decided not to use them. Pots could be used in the 556 oscillator circuits to make the clock rates variable. I use a free program called 555 timer pro to help model the circuits. Do a search on the net to find your best download options for that. Per print, this circuit will give you a dual flash per light and an approx toggle rate of 3 seconds. I'm doing this from memory so the math may prove otherwise on the toggle oscillator.) For my light fixtures, I found some inexpensive motorcycle marker lights that were small enough to fit on my wingtips. I took them apart and removed the existing lighting and substituted my own. When I built the plane, I ran wire through the wing spars before covering so that it would be available when I got ready to install this project.  The final result can be seen Here. My final cost was in the neighborhood of 50 or 60 bucks.  Far cheaper than the cost of aviation strobes and the added bonus that you can pat yourself on the back for doing it yourself. Home Page