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Mighty Mule

Mighty Mule FM231 Wireless Driveway Alarm – Electromagnetic Vehicle Detection, Indoor Receiver, 400 ft Range, Expandable, Battery Powered, Easy Installation, Driveway & Property Security System

  • Based on 4,137 reviews
Condition: New
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Availability: In Stock.
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Arrives Thursday, Jul 10
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Features

  • Electromagnetic Vehicle Detection: Detects vehicles using an electromagnetic sensor system, ensuring reliable notifications when vehicles enter or exit your property
  • Indoor Receiver with Audible Chime: The included receiver emits a chime when a vehicle is detected, promptly alerting you of any driveway activity
  • Up to 400 ft Wireless Range: Offers a wireless range from the transmitter to the receiver of up to 400 ft, providing security coverage for large properties
  • Easy Installation & Battery Powered: Simple to install by burying the sensor next to your driveway; powered by 2 AA batteries (not included) with a low battery indicator
  • Expandable System: Add multiple indoor receivers (sold separately) for broader coverage across different areas of your property
  • Mighty Mule driveway alarm, has been a trusted choice by customers for over 20 years. Additional base station can be purchased separately (FRM231-R)

Description

The Mighty Mule FM231 Wireless Driveway Alarm provides reliable vehicle detection to help secure your home, business, or property. Unlike traditional motion sensors, the FM231 uses an electromagnetic sensor system to detect the movement of large metal objects like cars, ensuring fewer false alarms caused by animals or pedestrians. Once a vehicle is detected, the sensor sends a signal to the indoor receiver, which alerts you with an audible chime. This driveway alarm offers a wireless range of up to 400 feet between the outdoor transmitter and the indoor receiver, making it suitable for monitoring larger properties or long driveways. The system is expandable, allowing you to add additional indoor receivers in different areas, ensuring you never miss an alert. The sensor is easy to install by burying it next to your driveway, and the battery-powered transmitter means no complicated wiring is necessary. The system operates on 2 AA batteries (not included) and features a low battery indicator for both the sensor and the receiver to prevent downtime. Designed to perform reliably in most outdoor conditions, the FM231 offers a durable and weather-resistant setup, although care should be taken to protect the transmitter from direct exposure to sprinklers or heavy rain. Whether you're securing a home, business, or rural property, the Mighty Mule FM231 provides an efficient, cost-effective solution for vehicle detection and driveway security. From the Manufacturer Keep track of vehicles entering or exiting your property with the Mighty Mule Driveway Alarm. (FM131) When a vehicle passes the sensor, the receiver emits an audible tone. Easy to Install and stake is included in kit. The electromagnetic sensor will sense large metal objects and send a signal to the interior base station to let you know someone is there. Install the batteries, near the installation site so the sensor can "learn" the area. If the batteries are installed in the home; the unit may not function properly.

Brand: Mighty Mule


Color: Multicolor


Power Source: cordless-electric


Compatible Devices: Compatible with Mighty Mule


Item dimensions L x W x H: 6 x 3 x 13 inches


Brand: ‎Mighty Mule


Color: ‎Multicolor


Power Source: ‎cordless-electric


Compatible Devices: ‎Compatible with Mighty Mule


Item dimensions L x W x H: ‎6 x 3 x 13 inches


Connectivity Technology: ‎Wireless


Alert Type: ‎Motion


Item Weight: ‎1.5 Pounds


Maximum Range: ‎12 Feet


Included Components: ‎Transmitter, Sensor, Receiver, Transformer, Mounting Post, Instruction Manual


Noise Level: ‎125 dB


Unit Count: ‎1.0 Count


Global Trade Identification Number: ‎01, 88


UPC: ‎723521743095 094713465348 728639291933 763500157772 090835001488 090835001600 090835001501 791043564047


Manufacturer: ‎Mighty Mule


Part Number: ‎FM231


Item Weight: ‎1.5 pounds


Product Dimensions: ‎6 x 3 x 13 inches


Country of Origin: ‎China


Item model number: ‎FM231


Is Discontinued By Manufacturer: ‎No


Size: ‎Pack of 1


Style: ‎Security System


Finish: ‎Multicolor


Material: ‎Plastic


Item Package Quantity: ‎1


Batteries Included?: ‎No


Batteries Required?: ‎Yes


Warranty Description: ‎Limited 12 Month Manufacturers Warranty (from date of purchase)


Date First Available: September 25, 2008


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Jul 10

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • An outstanding driveway sensor system
This sensor works exactly as described. It was easy to install following instructions - took about 1/2 hour. I placed the sensor adjacent to the drive paving about 50' up the drive from the street and placed the transmitter about 6' back from the drive near a lamp post for protection. I only buried the sensor and wire about 6" deep (hard ground) with no problem. I mounted the transmitter and one piece of the pipe on a piece of 1/4" plastic rod (electric fence post from Tractor Supply) which provides a solid support for the unit. I left the range setting at maximum and it seems to work fine for my location. I installed the receiver in the house about 200' from the transmitter. I had to test the receiver location and move it due to the construction materials in my house. My house is wrapped on the outside with heavy aluminum foil under the siding, which has caused me problems with wireless communication before. The best location for me was near windows in the direction of the transmitter. The receiver looks like a new model with some improvements from the product description and comments. The receiver has a volume control and the beeping sound is fairly loud when set at high. Actually I wouldn't want it any louder in our house. An additional change appears to be when the sensor sends an alarm, the receiver beeps 3 times at the volume set. The green (Visitor) light also turns on when the receiver gets a signal. You can reset it and turn off the green light if you like. I found it was handy to check the system - since we don't get much driveway traffic. Just reset it, leave for an errand and return. If the system is working, the green light will be on when you check the receiver. To clarify the alert actions, when the green light is off and an alarm sounds, the receiver will beep 3 times and the green light will come on. Every additional alert will beep 3 times and the green light will remain on. You can reset the green light manually at any time - or never. Have had the unit in service for 2 weeks so far without any problem. HAVE NEVER HAD A FALSE ALARM so far. This seems like a good solid well built unit and works exactly as we want. ... show more
Reviewed in the United States on March 1, 2017 by Ann Reads
    • Simple install, works as advertised
I'd almost purchased a different driveway alarm that worked by detecting (seeing?) motion, but then realized we have deer and other animals that would inevitably set off that type of device - and likely in the middle of the night which would make me want to hurl it against the wall in a fit of rage. So for my sanity I purchased this one and I'm very happy I did. It makes knowing when someone is driving up super simple, which is helpful when we might otherwise be letting the dogs out to play at just the moment the UPS driver is pulling up. I installed it about 12 inches down into the dirt next to my asphalt driveway, and per the instructions I set it back a little more than 25 feet from the road. I ran the cable from the magnetic sensor at the same depth of dirt about 6 feet away to where I installed the post. I didn't put anything inside PVC as some others have indicated, since I'm not aware of any critters that will eat the wires. I planted a bush (which the aforementioned deer have started eating) right in front of the post to make it less visible from the road. This works exactly as described. The driveway itself is wide enough for 2 cars to sit on it side by side, but in reality when someone drives on it they're in the middle so vehicle detection hasn't been a problem. The receiver sits inside the house a little over 100 feet directly from the transmitter. No problem with signal strength or reception. I will say the volume on the receiver is loud and I just haven't looked at it to see if it's adjustable. If it is, great. If not, no big deal - the receiver is in a corner in the kitchen out of the way and we can hear it fine from anywhere. Definitely meets my needs and does exactly what we wanted it for. ... show more
Reviewed in the United States on April 26, 2019 by Kermit Wallace
    • Frustration led to satisfaction finally
This is an excellent product. It has mostly clear and accurate instructions. However, let me give a more detailed description of my experience. My drive is long and in the front of our house. All our windows are toward the back, so we could never tell when someone was coming without standing at a window waiting. So, the idea of a remote sensor was very appealing. I read the reviews for this product and it seemed as though concerns about range were that it would work well for my needs. However, I didn't want this 1' tall pipe with the transmitter standing in the middle of the yard. I was hoping to find a longer cord from the sensor to the transmitter so I could hide it by a tree at about 30'. I called customer support for the company to see if this was possible and found out that the cable that connects them is a simple computer USB cable...they suggested that I could add a longer extension cable to make it possible to hide the transmitter farther away from the drive (the cable is only about 10' long). So, I ordered the unit and bought some extra 6' long USB extension cables. When the unit came, I had a beautiful mid-winter 60 degree day and went out to dig my trench for the unit. Since I was burying the USB with junctions, I bagged the connections in plastic and used heavy tape to keep water out. When I completed the task, the unit worked GREAT! Total success. However, the next morning, it didn't work! Why? I never could really figure it out. The connections were all snug and dry, but the transmitter only worked intermittently. VERY frustrating. I called the company again. They said that perhaps the batteries were not able to handle the cold (it was no longer 60 degrees and was below freezing over night.) So, I went out and bought lithium batteries....no difference. Not only was it intermittent, but the frequency of success seemed to diminish. I read the manual again and found that it says "Do not splice the cable". I concluded that this meant I should not use the USB extension cables, even though the tech told me I could do this. So, I took out the extensions and put the pole the 10' from the driveway (ugly). But it worked for a day, then seemed to stop again...back to intermittent success. Back to tech support....they advised "resetting" the unit...taking the battery out for 30 seconds, then reinserting to let it recalibrate. I did this a number of times...every time I reinserted the battery, the alarm would go off inside. This told me that the transmission was good, but there was something hindering the signal from the sensor to the transmitter. I was ready to give up and called the tech support again. He told me that they had done all they could do to help me over the phone and they gave me a return authorization. He told me that I should be sure it didn't work because if they got it back and it worked for them, they would just send it back to me. (I was not really happy at this point...) However, I decided I would remove the item....as I brought it back into the house with the batteries still inserted, it set off the alarm whenever I walked past something with even a little metal in it. Hmmmm...this told me that it WAS properly sensing and transmitting and that perhaps my line of sight in my original location was not as good as I thought. I reburied the unit in a different location that is farther away from the house and not as obvious that the pole is sticking out of the ground...it actually has a superior line of sight to the house and ... VOILA! It works perfectly and every time now. I can't say for sure what fixed it other than the different location must transmit better. So, this was very frustrating to get it set up. 1) You need to be sure you can avoid splicing the USB and have a transmission spot 10' from the driveway. 2) You do need lithium batteries. 3) Be sure you have excellent line of sight from the transmitter to the receiver location in the house (it does not need to be through a window, however)...I may have had zebra grass blowing about 1/2 way between my original location...don't know. 4) The alarm is loud enough to be heard throughout the house. It will send a new signal with each car (after about 15 seconds between). 5) Once it is working, DON'T TOUCH IT! (I really don't know if it would affect it, but I am not taking any chances. My rating is 4* because of the trials and frustration getting it to work. As for the way it works, it is great and worthy of 5*. It works just as advertised finally and we can now await our visitors sitting in the back of the house without seeing the driveway. Good product. ... show more
Reviewed in the United States on February 24, 2016 by Tom W.

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