A friend of mine has a bear denning on her property, and just noticed that he is getting ready to leave the cave, and will probably do so in just a couple of days. To get a video of it leaving the cave, she bought a video camera (
**broken link removed**) and asked me to help her set it up to automatically record the bear whenever it comes out. Because there is no time to order anything online, I picked up the only model of motion detector available in town (
Optex RX-40PI), and have been frantically trying to find a timing circuit to use with it and the camera. I can get some 555 chips and (some) discrete components, but probably only
very common values. As a motion detector sends out a signal as long as it sees motion, I need the circuit to trip a solenoid (to start the camera recording by pressing the 'record' button) as soon as the MD triggers it, then go into a timing loop, resetting every time the MD sends a signal, until a set period (e.g. 3 minutes) has gone by, when it triggers the solenoid again to stop recording and deactivates until the next signal from the MD.
While I can tell a transistor from a capacitor, and can put together a circuit from a schematic & pinouts,
designing such a circuit is beyond my skills.
Here are some further notes that I will add to as I go. I know enough to know that I might not be providing you with enough information, and would be happy to supply whatever you need.
- Project will be powered via **broken link removed**. (Two in parallel, so that one can be removed for recharging without disturbing the setup. Will that be all right?)
- Camera will be powered by charger plugged into inverter.
- Camera will be in a security camera enclosure.
- Camera can't be physically altered.
- Camera has a sliding switch that changes to night vision mode, which would be handy in case the bear shows up at dawn/dusk. I have some wide-angle, bright IR LEDs that can be slaved to add more light to the area.
- Solenoid will probably be 12v from an auto wrecker if I can't find anything lighter. (Suggested alternates?)
- Any time definite values aren't required, ranges (e.g. 100-470Ω) would be preferred, as local sources are slim.
If
any of you could post a schematic to such a circuit, I (and she) would be
extremely grateful.