One button, two beeps

[_]

Well, not beeps really, flashes.

I want a button on the car dash that I can hit that will flash both sets of
turn signals twice. A thank-you button. Hit the button once, get two
flashes. I don't think the simplest solution is to count the flashes that
the existing flasher makes, but a simple logic circuit that flips a relay.

 

[petrus bitbyter]

Well, not beeps really, flashes.

I want a button on the car dash that I can hit that will flash both sets
of
turn signals twice. A thank-you button. Hit the button once, get two
flashes. I don't think the simplest solution is to count the flashes that
the existing flasher makes, but a simple logic circuit that flips a relay.

Most simple circuit I can imagine consists of three timers. 555 types for
instance. The first timer starts when you hit the button and switches the
lights on. When it's timed out, it switches the lights off and starts the
second timer. Once this is timed out, it starts the third timer that turns
the lights on again until it's timed out.

petrus bitbyter

 

[ehsjr]

Well, not beeps really, flashes.

I want a button on the car dash that I can hit that will flash both sets of
turn signals twice. A thank-you button. Hit the button once, get two
flashes. I don't think the simplest solution is to count the flashes that
the existing flasher makes, but a simple logic circuit that flips a relay.

If your button & circuit ran the 4 way flasher for 2 cycles,
would that give you the "thank you" timing you want? If so, a
one-shot set long enough for 2 cycles would probably be simplest.

Ed

 

[MooseFET]

Well, not beeps really, flashes.

I want a button on the car dash that I can hit that will flash both sets of
turn signals twice. A thank-you button. Hit the button once, get two
flashes. I don't think the simplest solution is to count the flashes that
the existing flasher makes, but a simple logic circuit that flips a relay.

Look up the CD4060. It can turn on an N-channel MOSFET directly if
you run it on about 10V.

In the ap-notes see how to make an RC oscillator using it.

Use an RC circuit to make the button press into a reset pulse for the
4060.

Run one of the outputs (call it Q(N)) to the MOSFET.

Connect the anode of a diode to the Q(N+2) output. This limits your
option one what Q(N) is.

Connect the cathode of the diode to the oscillator's input.

When you reset the CD4060, the oscillator runs until Q(N+2) goes high
and then stops. Q(N) goes high twice during that time.

 

[_]

Look up the CD4060. It can turn on an N-channel MOSFET directly if
you run it on about 10V.

In the ap-notes see how to make an RC oscillator using it.

Use an RC circuit to make the button press into a reset pulse for the
4060.

Run one of the outputs (call it Q(N)) to the MOSFET.

Connect the anode of a diode to the Q(N+2) output. This limits your
option one what Q(N) is.

Connect the cathode of the diode to the oscillator's input.

When you reset the CD4060, the oscillator runs until Q(N+2) goes high
and then stops. Q(N) goes high twice during that time.

Perfect.

Thankyou.