Build these simple motorcycle alarms yourself using veroboard and cheap off-the-shelf components. They are suitable for 6-volt as well as 12-volt systems - so they'll protect your "Clasic Bike". In standby mode they use absolutely no current - so they won't drain your motorcycle battery.
Introduction
The prototypes of the Basic Motorcycle Alarms were built using only the Stripboard Layouts as a guide. So - if you have faithfully reproduced the layout - you will have a working circuit.
Once you're satisfied that your layout is correct - and you have made a careful and thorough check of the underside of the board - it's time to power-up the circuit and test its operation. This is always an anxious moment. If you construct a lot of circuits - you might consider building the
Current Limiting Power Supply - or alternatively - you could add the Simple Current Limiter to your existing PSU. Both will let you set an upper limit on the amount of current supplied to your circuit - and so protect it from any serious damage.
Circuit No.5 - Setup
A resistor and an LED are all that's needed to demonstrate that the "Siren" output is working properly - and you can simulate the trigger-switches using two short lengths of wire.
Connect an LED - in series with a 2k2 resistor - across the "Siren" terminals. I used a Yellow LED in the diagram but you can use whatever colour you have available.
Connect short lengths of wire to the "Tilt" and the "Negative" terminal. Strip the ends of the two wires - but keep them separate from one another.
Finally, connect the 12-volts DC to the input terminals. Pay particular attention to the polarity of the supply. Note that the positive connection goes to the board's centre terminal. Before you turn on the power - make sure that your "Tilt" switch wires are not touching each other.
Turn On The Power
Take the two wires you've connected to the "Tilt" switch terminals - and touch the ends together. The relay should energize and the yellow LED should light.
Next - separate the "Tilt" switch wires. If you've left out D3 - the relay should de-energize - and the yellow LED should turn off.
If you've included D3 - the relay should remain energized - and the yellow LED should remain lit. This means that the alarm is triggering and latching properly. Turn off the power. The relay should de-energize - and the yellow LED should turn off.
Repeat the test a few times - to make sure that the circuit is operating reliably.
Circuit No.6 - Setup
A resistor and an LED are all that's needed to demonstrate that the "Siren" output is working properly - and you can simulate the trigger-switches using two short lengths of wire.
Connect an LED - in series with a 2k2 resistor - between the "Siren" and the "Negative" terminals. I used a Yellow LED in the diagram but you can use whatever colour you have available.
Connect short lengths of wire to the "Tilt" and the "Negative" terminal. Strip the ends of the two wires - but keep them separate from one another.
Finally, connect the 12-volts DC to the input terminals. Pay particular attention to the polarity of the supply. Note that the positive connection goes to the third terminal from the top. Before you turn on the power - make sure that your "Tilt" switch wires are not touching each other.
Turn On The Power
Take the two wires you've connected to the "Tilt" switch terminals - and touch the ends together. The relay should energize and the yellow LED should light.
Next - separate the "Tilt" switch wires. If you've left out the solder-bridge in the top left-hand corner of the diagram - the relay should de-energize - and the yellow LED should switch off.
If you've included the solder-bridge - the relay should remain energized - and the yellow LED should remain lit. This means that the alarm is triggering and latching properly. Turn off the power. The relay should de-energize - and the yellow LED should turn off.
Repeat the test a few times - to make sure that the circuit is operating reliably.
If You Find a Problem
If - in the course of the test - you find that something is not working properly, then a careful inspection of the circuit board should turn up the cause of the problem. If the LED is not lighting - check that it's connected the right way round. Where you've cut the board to size - look for small loose strands of copper left behind by the saw. It can also happen that the stripboard itself is faulty. I have seen cases where the copper tracks have not been completely severed from one another during manufacture.
If you've built your circuit using the specified components - and you've followed the step-by-step construction guide described on the Support Page - then the chances are that any bug will be caused by something minor - a component connected the wrong way round - a missing or unwanted solder bridge - an incomplete cut in the track etc.
If you can't see anything obvious then adopt a systematic approach to faultfinding. Begin by double-checking that all of the cuts in the tracks have been made, that they are all - In The Right Place - and that they sever the track completely. Use a magnifying glass. It only takes the smallest strand of copper to cause a problem.
When you're satisfied that the tracks have been severed in all the right places, check that you have made - and correctly placed - all the solder bridges. Mark each bridge with a felt-tip pen - or something similar - so that it can be easily identified later.
Next, carefully examine the full length of each track. Look for unwanted solder bridges. Your felt-tip markings will tell you which ones should be there - and help you identify the ones that shouldn't be there.
If all else fails and you still haven't found the cause of the problem - work your way through the assembly instructions on the Support Page. Check each individual component and the link - to make sure that it's present and correctly positioned.
Print out the drawings and mark off the components as you go. Pay particular attention to the orientation of the diodes. Take your time and examine each individual component carefully.
SUGGESTIONS