Cobra 5462 Microwave Sensor

An Alarm microwave sensor (or super high-frequency volumetric sensor as Cobra call it) is ideal for soft top convertibles or other areas where ultrasonic sensors would not be suitable. Microwave Sensors are not sensitive to air movement.

 The sensor operation is based on the “Doppler effect” principle according to which a moving conductor object hit by electromagnetic waves at high frequency causes the beam to be reflected in a different way. If the reflected waves are measured the foreign body can be identified and an alarm signal can be generated.

Normally the sensor would be located in the centre of a car to detect if someone reaches in through the roof or an open window. However, there are other ways to install one as I shall explain soon.

The sensor can be adjusted to suit the vehicle and location. A small mass (such as a Human hand) will need to be closer to the sensor to trigger it than a large mass such garage door moving overhead.

Alarm Microwave Sensor

Possible sensor locations and adjustment zone

The sensor creates a virtual bubble, but will not detect beyond an existing metal object such as a car door.

Alarm Microwave Sensor

Microwave Field

It is vital not to have any metal obstruction close to the sensor, so areas, where coins may be stored, are not ideal.

The Microwave can be adjusted in a range up to about 2 meters and can be hidden under upholstery or dash panels depending on the material.

It’s worth noting that cell phones can interfere with a microwave sensor so do not leave your phone in a storage area in close proximity to the sensor when the alarm is armed.

Possible Locations and uses.

  • Central transmission tunnel under the trim
  • Behind rear seat
  • Roof panel facing downwards
  • Ute trays
  • Boat alarm (See below)
  • In the door (See below)

Custom Boat Alarm

One of the more interesting jobs I have recently done is a boat alarm. For this, I placed all of the components in a watertight box as shown below

Custom Boat alarm

Custom built Boat Alarm with Microwave Sensor built-in

I lined the case with tin foil before fitting the microwave sensor. This way it would only detect objects in front of it. I mounted the box in the fibreglass hull at the stern of the boat behind the entry steps.

Boat alarm

The case is fully waterproof as was the external Cobra 4310 siren. The buttons on the case of the box are simply for any future programming.

AC Cobra with Cobra alarm (What else would you use?)

I used a similar trick with tin foil in an AC Cobra replica recently. First I removed the carpet from the fibreglass door, then lined it with foil before fitting the sensor and reupholstering it.

Microwave in door

This allowed someone to walk past the door without upsetting the alarm, but as soon as the door is opened it would detect the person to trigger the alarm. The range was set to detect anyone getting in via the other side too.

It was a very tidy install where the car had no door switches to use. Retrofitting them into a fibreglass body was not a viable option.

Cobra 5462 Super High-Frequency Volumetric Sensor

Cobra Alarm Microwave Sensor

Cobra 5462 Microwave Sensor

RRP: $140.00

Works as dual zone sensor with some Cobra alarms

About Julian

Owner and Installer at Obsessive Vehicle Security Limited. More details here... Please keep Comments relevant to the post and use the Contact form for enquiry's
This entry was posted in Cobra, Obsessive Installs, Sensors and tagged , , . Bookmark the permalink.

5 Responses to Cobra 5462 Microwave Sensor

  1. Barry says:

    Hi Julian,
    Greetings from the UK, great site, refreshingly honest reviews & comments. I’d be interested to know how the Cobra microwave can work as a dual zone sensor & will this work on the 4600 series?
    Thanks. Baz

  2. Julian says:

    Hi Baz,

    I have not tested one with the 4600 as yet. Will put one on the bench and find out next week rather then second guessing.

  3. Julian says:

    The 5462 Microwave Sensor only works as a single zone sensor with the 4600

  4. Kay Knowles says:

    Hi Julian,

    I am thinking of buying an AVFA4 microwave sensor for my car.
    I can’t find any reviews on it as yet.
    Do you have info on this alarm, please?

  5. Julian says:

    Hi Kay, I’ve never heard of an AVFA4. After looking on Google it seems that they have not either. Have you made a typo? AVS A4 Maybe? If so avoid them as they are crap!
    I’d suggest getting a known brand which has been tested.

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.