Thanks again for the replies. From what ive found the flash sequence etc is down to make/model or aircraft. The main purpose is to aid in seeing it during the day and a flashing light is easier to see than a solid one. The red green is just because may help in direction but white is brighter.
Like i said small, simple and light is all i want.
The ones ive seen and mentioned are:
standalone with battery
https://flytron.com/led-light-systems/319-strobon-standalone.html

needs external power but give info on the flash times and power.
https://flytron.com/led-light-systems/99-strobon-navigation-strobe-light.html

With both of these and what i want to make I get the ideas above and using power transistors to run the led but how is it making the nearly 1amp into the led from the 90mha battery. I would expect a cap of some form to charge and power the flash but none look big enough.
As you can see this one is round and bigger and takes input from the rc receiver which i dont need or want so hopfully make is a lot smaller and external LED's. Yes the flash on multi led would be in sync.

Thanks

 

Do all the flashes need to be synchronized? An ATTiny85 is all you need to flash one led. It’s an 8 pin IC. You can duplicate the ATTiny85 for each led. Or, you can drive a BJT/ MOSFET to drive several LEDs in sync.

The code is simple. I’ve provided sample code below. This code works for one LED or several with a BJT or MOSFET (2N7000) driver.

#define lightPin 4
#define shortTime 3000
#define longTime 7000
#define onTime 1000
void setup() {
pinMode(lightPin,OUTPUT);
digitalWrite(lightPin,LOW);
}

void main() {
long endTime =0;
endTime=millis() + longTime;
while( millis()<endtime);
digitalWrite(lightPin, HIGH);
delay(onTime);
digitalWrite(lightPin,LOW);
endTime=millis() + shortTime;
While(millis()<endTime);
digitalWrite(lightPin,  HIGH);
delay(onTime);
digitalWrite(lightPin, LOW);
}

SparkFun makes a reasonable programmer for the ATTiny series of chips that lets you use the Arduino IDI to develop and upload your programs

This Is as good as what ive done using the addressable LEDs and the ATTiny but they are not that bright but using the mosfet to drive bigger led would be an option

 

I believe those 6 pin micros are 1k word variety out of China that can be had for about $0.03 each. They are OTP and have their own programmer and “mini C” coding language. They are appearing in all sorts of inexpensive things like the small battery powered Christmas blinking strings. I’m looking into it but the programmer and debugger is a small investment but there are folks working on an open source solution.

https://hackaday.com/2019/04/26/making-a-three-cent-microcontroller-useful/

switch the LEDs using tiny mosfets.

 

The requirement is a pair of flashes of about 20 milliseconds spaced about 2 seconds apart. That can be done with 2 or three IC devices and 2 transistors and NO PROCESSOR AND NO CODE! Why try to stick a power consuming processor on a project when cheap CMOS ICs will do the job and draw about 3 milliamps between the pulses? A CD4060 binary counter and a CD4017 decoded decimal counter, and a CD4049 hex inverter are all that is needed. And two transistors to switch the LEDs on for about 20 milliseconds. Also probably 2 resistors and a small capacitor. That is simple and reliable and quite compact. And no need for any code or processor to suck down the battery power.

 

The requirement is a pair of flashes of about 20 milliseconds spaced about 2 seconds apart. That can be done with 2 or three IC devices and 2 transistors and NO PROCESSOR AND NO CODE! Why try to stick a power consuming processor on a project when cheap CMOS ICs will do the job and draw about 3 milliamps between the pulses? A CD4060 binary counter and a CD4017 decoded decimal counter, and a CD4049 hex inverter are all that is needed. And two transistors to switch the LEDs on for about 20 milliseconds. Also probably 2 resistors and a small capacitor. That is simple and reliable and quite compact. And no need for any code or processor to suck down the battery power.

MisterBill2
Thanks for the info, Im ok with some basic programming on arduino type devices but am no where near good enough to work out how you would put together your 2 suggestions. Would you mind expanding on how you would do it. I chose 2 short but hopefully bright flashes as im thinking it would make seeing it a lot easier. the plan is to help in visibility during the day.
These little .03 cent/pence chips look good but as wolframore said they need a programmer etc so not for now.
Red and green was an idea to help with direction but white is better to see and power and weight is an issue i need to consider.

Thanks
Lee

 

Attiny85, setting clock to 4 mhz internal RC osc, running at 5V you're sipping 3mA active. Plus if you need to only flash them at 20mA or less you don't need switching transitors. If you really want to get miserly (not sure why you would need it... if this is for RC - this little amount is nothing) you can put on the watchdog timer between pulses and get to less than 8 uA between pulses.... but it's your project. You can even get better if you use lower voltage but switching gets a little more challenging.

 

Attiny85, setting clock to 4 mhz internal RC osc, running at 5V you're sipping 3mA active. Plus if you need to only flash them at 20mA or less you don't need switching transitors. If you really want to get miserly (not sure why you would need it... if this is for RC - this little amount is nothing) you can put on the watchdog timer between pulses and get to less than 8 uA between pulses.... but it's your project. You can even get better if you use lower voltage but switching gets a little more challenging.

And you can use an Arduino UNO as a programmer. Or for plug & play programming with the Arduino IDE, Sparkfun has a programmer for $15-$20.

 

I will need to sketch the circuit on paper and scan it to produce a PDF that I can post. What it looks like is that it will use 3 IC devices, a CD4049 hex inverter, a CD4017 decimal counter, and a CD4040 12 staGE BINARY COUNTER. Also a resistor and a capacitor for the oscillator . That is about as simple as I can make it. It can safely operate on between 4 and 15 volts, Th clock oscillator that generates all of the timing will run at 50Hz, and setting that frequency is the one adjustment that you need to make. That frequency is determined by the resistor and capacitor and so hopefully somebody can simulate it and arrive at the values for close to 50Hz.The oscillator uses one section of the hex inverter IC. The output of that inverter als feeds the clock inputs of both the CD4017 (pin 14)and the CD4040 (pin 10). The Q12 output of the CD4040 (pin 14) feeds the input of a second inverter on the CD2029, and the output of that second inverter feeds the "clock inhibit" input on the CD4017 (pin 13) . The "9" decded output of the CD 4017 (pin11) feeds the "reset pin on the CD4040 (Pin 11) The decoded "1" on the CD 4017 (pin 2) feeds the inputs of two inverters of the CD4049, and the outputs of those 2 invetres feed the cathodes,(-side) of one LED. The decoded "5" of the CD4017 (pin1) feeds the inputs of the last 2 inverters of the CD4049, and the outputs of those inverters feed tha cathode of the other LED. The + side of both LEDs connects to the positive supply. A series resistor may be needed, depending on the LED types ratings.
The CD4017 and CD4040 both have the positive supply connected to pin 16, and the supply negative side connected to pin 8. For the CD4049 the positive supply connects to pin 1 and the negative connects to pin 8. All 3 ICs use 16 pin sockets
I hope that this description is adequate for you to build the circuit. .