Wireless Driveway Monitor

Background
Description
Operation
Photos
Related
References
Links

Background

In the past I have used the PSR-1 geophone based sensor and the Harbor Freight 93068 PIR driveway sensor. The PSR-1 works well when connected to a speaker where you "hear" the infrasonic vibrations and can intuitativley recognize. The 93068 works but both units have a short battery life.

This STI 34100 unit uses a magnetometer based sensor that's solar powered (uses a couple of Ni-Cad AA batteries) and a line powered indoor receiver. The PIR sensor sometimes was triggered by cars going by in the street (probably reflections) and by deer, but the magnetometer should only respond to vehicles in the driveway. I have placed it over 12 feet from the street and so far it has not alarmed on passing vehicles.

Description

I'm not sure what type of magnetic sensor is used, but it's sensitive enough that just waving the sensor is enough to trigger an alarm because of the change in the Earth's magnetic field.
There are two STI brand magnetometer driveway alarms, this one that has solor power (the sensor is green and looks like a flying saucer). The other version (STI-34159) uses alkaline C-cell batteries to power the gray sensor that looks like a beehive.

Operation

After removing three (+) screws on thesolar sensor the bottom cover comes off exposing the two Ni-Cad AA batteries and a jumper for setting the sensivity.
It came with the jumper to the right (batteries toward top) which is maximum sensitivity.

It also needed to be programmed (Reference the YouTube video: Program and clear memory)

After the receiver has unplugged for at least 15 seconds.
Press and hold the gray button while plugging in the power.
Keep holding the button until all the sounds have stopped then wait 10 seconds.
If the red LED in the button is on or blinking tap the button to turn it off.
Waive the sensor back and forth. The receiver should sound an alarm and the red LED in the button will remain on indicating a trip.
Every now and then the normally green power on indicator may flicker indicating that it's pinging the sensor. If the sensor battery is low or does not repond for 24 hours there will be a trouble indication.

Adding Second Sensor

First clear receiver memory.
Unplug for 15 seconds then plug in. Within 5 seconds press and hold down gray button until beeping changes to solid tone then release button. Memory now cleared.

Bring both sensors inside near receiver.
Unplug receiver for 15 seconds. Press and hold gray button then plug-in power. Keep holding gray button until beeping stops. Within 60 seconds of power up shake each sensor.
The first sensor to be paired will beep one time, the second will cause two beeps, &Etc.

You can confirm pairing by shaking a sensor and waiting up to 30 seconds for the receiver to beep the correct number of times. In this case once or twice.
Now take sensors back to driveway and tap gray button to turn off red LED.

Mounting Sensor

I hung the STI-34150 battery powered driveway sensor (Fig 5) on a tree limb near the driveway, but it's been causing false alarms. The alarm starts with 2 beeps so I know which sensor. Probably because of wind moving the branch.
So in order to minimize false alarms the sensor needs to be mounted in a rigid way. Next to screw it onto a tree trunk.

Photos

Fig 1 Purchased on eBay as a used unit missing the antenna.

Fig 2 Parts in the box (missing antenna and cap for driving stake).

Fig 3 Sensor installed near driveway and tilted South for more
solar power.

Fig 4 STI-34104 receiver with 6-32 screw screwed into antenna phono jack
and a 14" long clip lead acting as the antenna.
If the frequency is 433 MHz then a quarter wave antenna should be about 7" long
but this seems to be working.

After driving away and returning the red LED was blinking, so it's working.

Green power on indicator showing green in photo.

Fig 5 STI-34150 battery powered driveway sensor
Runs on 2 ea: C batteries, no solar. Good for shady locations.
Uses PIC16F636 micro controller and
PNI magneto inductive sensor.
The diagonal bar is the transmit antenna.
Just above the right end of the antenna is a piezo chirper
that makes noise when the magnetic field changes so confirm
proper operation. Very faint when cap screwed on.
Sensor is at top of board.
Sensitivity jumper to the right "High" Position

Magnets -

References

Wireless Driveway Monitor (solar powered) STI-34100 -
4-Channel Receiver STI-34104 - including video on how to clear and pair (program) to sensors (YouTube)

Links

PRC68, Alphanumeric Index of Web pages, Contact, Products for Sale
Page Created 16 Aug 2016

Fig 1 Purchased on eBay as a used unit missing the antenna.	Fig 2 Parts in the box (missing antenna and cap for driving stake).
Fig 3 Sensor installed near driveway and tilted South for more solar power.	Fig 4 STI-34104 receiver with 6-32 screw screwed into antenna phono jack and a 14" long clip lead acting as the antenna. If the frequency is 433 MHz then a quarter wave antenna should be about 7" long but this seems to be working. After driving away and returning the red LED was blinking, so it's working. Green power on indicator showing green in photo.
Fig 5 STI-34150 battery powered driveway sensor Runs on 2 ea: C batteries, no solar. Good for shady locations. Uses PIC16F636 micro controller and PNI magneto inductive sensor. The diagonal bar is the transmit antenna. Just above the right end of the antenna is a piezo chirper that makes noise when the magnetic field changes so confirm proper operation. Very faint when cap screwed on. Sensor is at top of board. Sensitivity jumper to the right "High" Position