Inforad siren modification

[tigersaw]

For DarrenSV650S, and anyone else who was on the thread about this, which I have lost..

I have managed to interface a siren to the inforad M1 bike GPS thats fitted to the bike.
The idea was that the siren would go off when the warning LED first comes on, and continues if it is flashing - i.e. speeding, otherwise it would cancel. Simply interfacing a siren to the red LED would mean the thing going off all the time at traffic lights etc.

Rather than build something from scratch, it was much easier to buy a timer kit from maplin and modify it.
The timer kit is VF06G - costs £7.99 and can be assembled in the time it takes to drink a coffee. Other cost was the 12v siren, and a small box. The siren can be anything, in fact the bike horn could be used, its a relay output.

The circuit is modified as below:



C2 is changed to 2.2uf to change the timer range to 0 - 10 seconds approx.
The TIP122 is used as an inverter, to change the trigger (LED drive) from +2.7v to a ground signal. Any NPN transistor used in saturated mode would work, I just had this one handy. The capacitor and 5k resisitor is used to make the curcuit work on edge triggering only, so that a constant LED on will only cause one trigger, but a flashing LED will cause the circuit to continually retrigger.
The additional switch (shorting the capacitor on the trigger input) allows the circuit to self test when you turn the ignition on - not good if you start the bike early in the morning.

I fit the device under the seat next to the inforad, using the same fused DC supply:



This is on my ER6 - I forget what the underseat looks like on the SV. I connected the siren via a phono connector - allows me to disconnect it should I want things silent, or if it all went pete tong.

I have tested it plenty around Southampton in the last few days, works a treat - its plenty loud enough to grab attention without having to look at the LED wand thingy. It will continue until you slow down and the LED goes constant.
The only thing I have noticed is that if you speed up again after you have passed the camera, the red LED will flash again and cause it to sound again, but I guess thats just it doing its job properly


Inside the box:

[DarrenSV650S]

Thanks for posting that

So I need this, this, this, this and a 5K resistor (can't find a single resistor on maplin, only big boxes). What size is the other capacitor?

Darren, i can easy swipe a couple 5K resistors and post them down to you if you want..

I owe you for the bar ends anyways..

[tigersaw]

Yes I think those links are correct.
The extra bits are,
2.2 uf capacitor, TIP122 or similar, 2k and 5k resistor, (you could use the R6 4.7k one in the kit, as its not required, its used for the reset switch which I didnt require)
The two unidentified capacitors are, ummm probably 0.01 uf, (WW18U), but anything up to 0.1 should work - as I said, I just used stuff out the junk box. The 2k resistor could just as easily be a 1k.
Also a switch to use as the self test switch.
The siren I used was YD84F, fits in the side plastic nicely. If you want to use the bike horn, then check how much power it consumes. If more than 1 amp, then I'd either not use it at all, or run a separate fused supply to point A on the circuit.

[tigersaw]

Inside the plastic box:

[DarrenSV650S]

Ok thanks again Tiger

Originally Posted by saoralba

Darren, i can easy swipe a couple 5K resistors and post them down to you if you want..

I owe you for the bar ends anyways..

That would be great. Have you got a 2K one too?

[yorkie_chris]

Cracking idea.

...plus, if the siren is the right sort, when you're "making progress" the cagers should hear you coming and assume you're a copper and get out of the way.

Darren what do you need exactly..?

Couldn't find any 5K resistors, theres 4.7K and ones slightly over 5K..

[dyzio]

There's no 5k resistors (in mrs16 size) , you can get 4k7 abd 5k6 or you could get precision resistors (4k99), similar with 2k.

I could find some for saoralba, next time I see him.