Extremely Simple PIR Prop Trigger Version 3
About three years ago I posted a tutorial on how I use a PIR driveway alert to trigger props that use a sound sensor for their trigger. That tutorial was very basic and described only using the driveway alert right out of the box to trigger sound activated props. While this worked very well there was still a little annoying chime when the driveway alert activated. The post received a lot of feedback along with some great suggestions. This tutorial uses the same driveway alert but has a simple modification based on wonderful suggestions from other forum members, especially BobbyA, that makes this trigger even more effective. I use this PIR trigger system on all of my sound activated props (and I have a lot of them) and it works great every time. You should be able to complete this setup within a couple of hours.
Materials:
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1 - Driveway Alert – About $10 - $16 on sale at Harbor Freight
2 - Small gauge speaker wire – About $8 per 25’ roll at Lowe’s Hardware
3 – Wire connectors - Abut $4 per package. You will need both male and female connectors
4 – A 5 or 10 ohm resister - $about $4 per pack of 5
5 - Can of flat black spray paint - $1.00 at Walmart
Tools:
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1 – Small screwdriver
2 – Heat gun or hair dryer
3 – Soldering iron with rosin core solder for electrical connections
4 – Wire cutters
5 – Wire strippers
6 – Wire crimpers
7 – Dremmel tool or small cutting tool
8 – Glue gun with glue sticks
Ok, let’s get started.
Step 1: Open the driveway alert receiver case and locate the speaker. Using the small wire cutters cut the wires to the speaker. Leave enough wire on both ends to allow adding wire to extend the speaker from the case.
Step 2: Using the Heat gun to soften the glue holding the speaker remove the speaker from the case. Use caution. It will take only a little heat so soften the glue enough to remove the speaker. Too much heat will warp the plastic case. It helps if you use a small screwdriver to carefully lift the speaker from the case.
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Step 3: Strip the insulation from the cut ends of the speaker wires and from the ends of the wire you are adding to the speaker.
Step 4: Using the soldering gun and solder, solder a short length of wire to the cut speaker wires then use the glue gun and glue insulate the connection with a dab of glue Note: I am not great at soldering but you don’t have to be. It doesn’t have to be pretty. But if you don’t want to try soldering the wires you can just twist the wires of any of these connections together and hold them together and insulate them with a dab of glue from the hot glue gun.
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Step 5: On the other end of these speaker wires attach wire connectors. Set this aside for now.
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The finished conmections should look something like this. Set this part aside for now.
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Step 6: Now moving to the driveway alert case, using the soldering gun and solder attach a 5 or 10 ohm resister to one of the speaker wires inside the driveway alert case
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Step 7: Next using the solder gun and solder attach a short length of new speaker wire to the speaker wires in the driveway alert case. This wire needs to be long enough to exit the case. Now using the wire crimpers crimp a female connector on the ends of the wire.
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Step 8: Using the glue gun and glue, secure the soldered ends of the wire to the inside the plastic case. This will secure the wire as well as provide insulation for the electrical connections. Be sure the connections are in a space that is away from the circuit board and will allow the plastic case to be put back together.
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Step 9: Using the dremmel or some other similar small cutting tool cut a hole in the driveway alert plastic case to allow the speaker wires to exit.
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Step 10: Put the case back together and using the glue gun and glue secure the speaker wires in the exit hole.
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Step 11: Now take the speaker and wire assembly and using the glue gun and glue secure the driveway alert speaker over the sound sensor of your prop (in this case my interactive talking pumpkins). Just use a little glue around the edge of the speaker to secure it to the prop then secure the wires to the prop with glue to keep them from pulling away.
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Step 12: Now you need some a speaker wire assembly to connect the PIR receiver to the speaker. Cut a length of speaker wire to whatever length you need and then crimp male connectors on each end.
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Step 13: Using the hot glue gun and glue put a dab of glue over the speaker hole in the plastic receiver case. This will keep paint from going inside the receiver when you paint the case.
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Step 14: Now paint both the PIR sending unit and the receiver flat black.
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That's all there is to it. When you are ready to set the assembly up just put the PIR sending unit wherever you want to trigger the prop. Put the prop with the speaker attached in place. Put the receiver where you want it by the prop and connect the receiver and the prop together with the wire you made in step 12.
One note of caution however. If you use more that one of the driveway alerts to trigger different props be sure to get driveway alerts that operate on different channel frequencies. If you don’t every time one prop is triggered every other prop on that frequency will trigger at the same time. I learned this the hard way. There should be a sticker on the box with the channel for the alert close to the USP code bar.
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Here is how the setup works on this prop.
I hope this is useful.
About three years ago I posted a tutorial on how I use a PIR driveway alert to trigger props that use a sound sensor for their trigger. That tutorial was very basic and described only using the driveway alert right out of the box to trigger sound activated props. While this worked very well there was still a little annoying chime when the driveway alert activated. The post received a lot of feedback along with some great suggestions. This tutorial uses the same driveway alert but has a simple modification based on wonderful suggestions from other forum members, especially BobbyA, that makes this trigger even more effective. I use this PIR trigger system on all of my sound activated props (and I have a lot of them) and it works great every time. You should be able to complete this setup within a couple of hours.
Materials:
1 - Driveway Alert – About $10 - $16 on sale at Harbor Freight
2 - Small gauge speaker wire – About $8 per 25’ roll at Lowe’s Hardware
3 – Wire connectors - Abut $4 per package. You will need both male and female connectors
4 – A 5 or 10 ohm resister - $about $4 per pack of 5
5 - Can of flat black spray paint - $1.00 at Walmart
Tools:
1 – Small screwdriver
2 – Heat gun or hair dryer
3 – Soldering iron with rosin core solder for electrical connections
4 – Wire cutters
5 – Wire strippers
6 – Wire crimpers
7 – Dremmel tool or small cutting tool
8 – Glue gun with glue sticks
Ok, let’s get started.
Step 1: Open the driveway alert receiver case and locate the speaker. Using the small wire cutters cut the wires to the speaker. Leave enough wire on both ends to allow adding wire to extend the speaker from the case.
Step 2: Using the Heat gun to soften the glue holding the speaker remove the speaker from the case. Use caution. It will take only a little heat so soften the glue enough to remove the speaker. Too much heat will warp the plastic case. It helps if you use a small screwdriver to carefully lift the speaker from the case.
Step 3: Strip the insulation from the cut ends of the speaker wires and from the ends of the wire you are adding to the speaker.
Step 4: Using the soldering gun and solder, solder a short length of wire to the cut speaker wires then use the glue gun and glue insulate the connection with a dab of glue Note: I am not great at soldering but you don’t have to be. It doesn’t have to be pretty. But if you don’t want to try soldering the wires you can just twist the wires of any of these connections together and hold them together and insulate them with a dab of glue from the hot glue gun.
Step 5: On the other end of these speaker wires attach wire connectors. Set this aside for now.
The finished conmections should look something like this. Set this part aside for now.
Step 6: Now moving to the driveway alert case, using the soldering gun and solder attach a 5 or 10 ohm resister to one of the speaker wires inside the driveway alert case
Step 7: Next using the solder gun and solder attach a short length of new speaker wire to the speaker wires in the driveway alert case. This wire needs to be long enough to exit the case. Now using the wire crimpers crimp a female connector on the ends of the wire.
Step 8: Using the glue gun and glue, secure the soldered ends of the wire to the inside the plastic case. This will secure the wire as well as provide insulation for the electrical connections. Be sure the connections are in a space that is away from the circuit board and will allow the plastic case to be put back together.
Step 9: Using the dremmel or some other similar small cutting tool cut a hole in the driveway alert plastic case to allow the speaker wires to exit.
Step 10: Put the case back together and using the glue gun and glue secure the speaker wires in the exit hole.
Step 11: Now take the speaker and wire assembly and using the glue gun and glue secure the driveway alert speaker over the sound sensor of your prop (in this case my interactive talking pumpkins). Just use a little glue around the edge of the speaker to secure it to the prop then secure the wires to the prop with glue to keep them from pulling away.
Step 12: Now you need some a speaker wire assembly to connect the PIR receiver to the speaker. Cut a length of speaker wire to whatever length you need and then crimp male connectors on each end.
Step 13: Using the hot glue gun and glue put a dab of glue over the speaker hole in the plastic receiver case. This will keep paint from going inside the receiver when you paint the case.
Step 14: Now paint both the PIR sending unit and the receiver flat black.
That's all there is to it. When you are ready to set the assembly up just put the PIR sending unit wherever you want to trigger the prop. Put the prop with the speaker attached in place. Put the receiver where you want it by the prop and connect the receiver and the prop together with the wire you made in step 12.
One note of caution however. If you use more that one of the driveway alerts to trigger different props be sure to get driveway alerts that operate on different channel frequencies. If you don’t every time one prop is triggered every other prop on that frequency will trigger at the same time. I learned this the hard way. There should be a sticker on the box with the channel for the alert close to the USP code bar.
Here is how the setup works on this prop.
I hope this is useful.
