GPS trackers and alarm sirens in the test effective protection or annoying toy?
Effective protection or annoying toy? gps-tracker and alarm sirens should secure motorhomes. We tested eight very different devices between 15 and 250 euros.
If you want to protect your car against burglary or theft, you have probably already thought about installing an alarm system. systems for fixed installation are affordable with prices starting from 200 euro, but meter-long wiring harnesses and many additional sensors cause a high installation effort. We were therefore interested in the question of what portable anti-theft systems do that do not need to be installed, but are simply connected to the power supply or are equipped with a built-in battery.
basic question: loud or silent alarm?
our test field is basically divided into two groups: on the one hand, these are pure alarm sirens, which are triggered by a motion sensor and then emit a more or less loud alarm sound. The other group is GPS trackers that do not emit sound, but report theft attempts and other data to the cell phone.
a mixture of both systems is the bosch spexor, a mobile universal sensor with app-control and further additional functions up to smarthome-integration. its motion detector also triggers an alarm sound on request, but its volume is far behind that of the other test candidates.
Alarm sirens in test
For the three alarm sirens we have chosen different concepts. What they all have in common: determined long-fingered people will hardly be impressed by them. However, it is conceivable that the alarm sounds will provide a moment of surprise and thus send opportunistic thieves running.
Technaxx TX-100

Price device: 29,97 €
other features/accessories: built-in battery, 2 x USB out (2.1 A), remote control
dimensions (l x w x h): 32 x 32 x 115 mm
attached user manual: yes, multilingual, also german, understandable; with QR-code for YT-video
test and measurement values:
loud alarm, one meter: 93,4 db, unpleasant sound
sensor sensitivity during test setup: already when reaching in, top!
Sensor types (vibration/GPS/noise)movement (three meter radius)
false alarms: when passing by, when window slightly open
power supply/accumulator life: twelve-volt cigarette lighter
handling (time to activation, reactivation, switch off)charging time three to four hours, stand-by six days
other: false alarm when someone passes by with the window slightly open
promobil test rating: conditionally recommendable
Mengshen KS-SF04R

price device: 14,99 €
other features/accessories: panic button, doorbell, no batteries, remote control (with batteries)
dimensions (L x W x H)85 x 43 x 14 mm
attached user manual: english only
Test and measured values:
volume alarm, one meter97 db, unpleasant sound
sensor sensitivity during test setup: only when putting in
sensor types (vibration/GPS/noise): vibration
fehlauslosungen: no, not possible
power supply/accumulator life: 2 x AAA (not included)/4 year
handling (time until start-up, reactivation, switch off): simple, except for adjusting the sensitivity: different buttons must be pressed exactly according to the plan; four years stand-by
miscellaneous: first short alarm, with further sensor triggering continuous alarm
Promobil test rating: conditionally recommendable
Cpvan PIR motion detector alarm

Price device: 24,99 €
other features/accessories: remote control (with button cell), battery (3 x AAA), adhesive pad, but also power supply connection (not included), expandable with additional sensors or remote controls
dimensions (L x W x H): 70 x 40 x 85 mm
enclosed operating instructionsyes, also in german, written tiny
Test and measurement values:
volume alarm, one meter102,4 db, unbearable in the car
sensor sensitivity during test installation: when opening the door
sensor types (vibration/GPS/noise): movement (five to eight meters)
false alarms: no, not possible
power supply / battery life: 3 x AAA (included)
handling (time until activation, reactivation, switching off): fiddly, not self-explanatory remote control. Symbols that can mean anything. Can also be armed/disarmed on the device itself
other: whoever writes a review gets a second remote control
Promobil test rating: recommended
Alarm sirens in test
Simple handling
the simplest form of retrofit alarm systems comes from the far east and costs only about 15 euro. The device from mengshen reacts to vibrations, but the intruder has to plop down on a car seat for this, because the sensors are not particularly sensitive. When the siren then shrills, it becomes quite uncomfortable at 97 db in the immediate vicinity. A small remote control in vehicle key optics ends the spectacle. In its functionality, the device is self-explanatory. Therefore, the lack of a German user manual does not disturb.
the technaxx motion detector is just as easy to use by plugging it into the twelve-volt socket of the cigarette lighter. But this disqualifies it at the same time for use in all those vehicles in which the positioning of said socket above the opening does not leave at least twelve centimeters of space for the sensor head. In the test, the device convinces with its sensitivity. The TX-100 alarms when reaching through a slightly open window. With a noise level of only 93 db, the despite its unpleasant timbre, however, does not turn out to be particularly loud. Practical are the two built-in USB slots, which can be used to charge smartphones, for example.
The third alarm siren scores points for its ability to connect several devices of the same type in series. so if you want to protect a larger vehicle such as a motorhome, this is a good choice. When the motion detector is activated, more than 102 db of noise will drive anyone’s ears out of joint. the only drawback is the fiddly operation of the cpvan siren, because the icons on the buttons of the remote control do not give a clear indication of their function. Nevertheless, the device emerges as the best from the test.
GPS tracker in the test
There were also major differences in GPS trackers. The devices from PAJ, salind and carlock are direction finding transmitters that are plugged into the on-board diagnostic (OBD) interface in the vehicle and thus also receive their power. Almost all current cars have such an interface, which is usually located on the driver’s side in the lower area of the dashboard.
PAJ car OBD finder

Price of the device: 99,99 €
data rate of the device per month/per year: 4,99 €/49,99 €
mobile radio: yes (4G), SIM built-in
special features: live tracking of position, 100 days track memory, tracks with time and speed, geofencing as circle or polygon, multiple trackers via portal resp. Cell phone app available.
Dimensions (lxwxh): 50 x 49 x 22 mm
enclosed operating instructions: no, reference to online portal via QR code
Test and measurement values:
notification types: push message cell phone
time until message is sent to cell phone: under ten seconds
types of alarm triggering, transmitted information: vibration alarm, ignition on/off, speeding, power interruption (remove from OBD interface), leaving a previously set area (circle or polygon), locating vehicle
power supply / battery life: permanent via OBD/ battery twelve hours
handling (registration, start-up, reactivation): register online, choose tariff, then download app and unlock device (payment via paypal or credit card), ready to use immediately
Promobile test rating: conditionally recommendable
Carlock auto-tracking& alarm system

price of the device: 59,99 €
data rate of the device per month/per year: 7,90 €/95,00 €, first month for free
mobile radioyes (4G), SIM built-in
special features: SMS and phone notifications additionally bookable. Monitoring of battery voltage as well as riding style (built-in accelerometer), multiple trackers available in portal/app.
Dimensions (lxwxh): 67 x 50 x 25 mm
user manual included: no, online portal with wild mix of english, german and italian
Test and measurement values:
notification types: push message cell phone, SMS, phone call
time until message is sent to cell phone: less than five seconds
types of alarm triggering, information transmitted: alarm on movement, vibration, over speed, ignition on/off, strong acceleration/braking, low battery, device disconnected, no GPS; note: tracking lags 30-60 seconds, no area polygons definable
power supply/accumulating time: permanent via OBD/ battery (not specified)
handling (registration, start-up, reactivation): register online, download app and enter device number, ready to use (paypal or credit card). SIM card must be replaced if deactivated for more than one month
Promobil-testwertung: conditionally recommended
Salind 4G OBD GPS tracker

Price of the device: 79,99 €
data rate of the device per month/per year: 4,99 €/49,99 €
mobile radio: yes (4G), SIM built-in
special features: live tracking of position, 100 days track memory, tracks with time and speed, geofencing as circle or polygon, multiple trackers via portal or. cell phone app available.
Dimensions (lxwxh)67 x 50 x 25 mm
enclosed instruction manual: no, reference to online portal via QR code
Test and measurement results:
notification types: push message cell phone
time until message is sent to cell phone: under ten seconds
types of alarm triggering, information transmitted: vibration alarm, ignition on/off, overspeed, power interruption (remove from OBD interface), leaving a previously set area (circle or polygon), locating vehicle
power supply/accumulator life: permanent via OBD/ battery twelve hours
handling (registration, commissioning, reactivation): register online, choose the tariff, then download the app and unlock the device (payment via paypal or credit card), ready to use immediately
Promobil-testwertung: recommended
Prothelis meintal GPS tracker
Price of the device: 139,00 €
data rate of the device per month/per year: 3,79 €/50,28 €
mobile radio: SIM built-in (not specified)
special features: tracking interval selectable from ten seconds to 24 hours, geofencing as circle or polygon, temperature sensor, manual SOS button, call instead of push message, multiple trackers available in portal/app.
Dimensions (lxwxh): 120 x 57 x 20 mm
enclosed instruction manual: yes, also in german, tiny writing
test and measurement:
notification modes: push message cell phone, phone call
duration until message is sent to cell phone: under five seconds
types of alarm triggering, transmitted information: alarm when leaving/entering an area (several areas definable, also as polygons), speed warning, alarm when moving/stopping, too high/low temperature, tracking of the route, charge level of the battery, speed history
power supply / battery life: battery up to 500 days, USB charger (cable included)
handling (registration, commissioning, reactivation)register online, choose a tariff and activate the device, download the app and register the device (payment via paypal, direct debit, klarna, credit card), ready for immediate use
Promobil test rating: recommendable
GPS tracker in test
Additional basic fee
The devices have a GPS antenna for positioning and a built-in SIM card for data connection to a cell phone app. Therefore, in addition to the purchase price of the device, there is a monthly or monthly fee. Annual base fee added. The location of the vehicle can be called up on the map of the cell phone app and even recorded.
The app can also be used to set the type of sensor information for which a notification is to be sent. For example, areas can be defined that trigger a message when they are left – and this message can also be triggered when the vehicle ignition is switched on or off. Switched off, a vibration detected or a predefined speed exceeded. This function is intended, for example, for parents who want to prevent their children from running around too fast. The trackers tested also report when they are removed from the OBD power supply. A built-in battery provides emergency power for several hours.
The tracker from carlock also provides information about driving style: an acceleration sensor measures g-forces and squeals about brisk driving. In addition, carlock also provides information via phone call or SMS (20 cents/SMS or. call), which in some circumstances attracts more attention than a message on a cell phone.
The GPS tracker from prothelis occupies a special position. This has a large battery, which should last up to 500 days. The device can therefore be flexibly installed, and its temperature sensor also reports how warm or cold it is in the car, caravan or house at any given time. In the test, all trackers functioned reliably, and the start-up also worked right away. The devices from PAJ and salind are almost identical except for the price and even share the online portal and app. There were minor differences in the speed of notification, but these were mainly due to the network coverage.
We found the apps to have varying degrees of clarity. Here, too, the prothelis tracker stood out positively, but without making the other apps look bad. Interested parties can therefore base their purchase decision on the costs or benefits of the system. Making the equipment differences dependent.
Alternative with additional benefits
Only twelve centimeters high, but packed with technology: the spexor from bosch scans its surroundings with various sensors and thus qualifies for different areas of application. The device combines the readings of the built-in motion, noise and pressure sensors for monitoring purposes. In the event of an anomaly, spexor sends a notification to the corresponding app on the owner’s smartphone via mobile radio.
In addition, the leds on the device itself light up and simultaneously emit a whistling alarm tone. This proves to be unimpressive in practice, but the strength of the device lies in its versatility. A temperature alarm can also be set for freely selectable minimum or maximum values. Spexor can even record and monitor air quality, and additional functions can be added for a fee. The app makes it easy to call up the data collected, and multiple devices can also be created in one account. In the first year, the service is free of charge; from the second year on, an annual fee of around twelve euros is charged.
Conclusion
A motion sensor with a small radius is less susceptible to false triggering than a vibration sensor. This circumstance and the loudness give the alarm siren of cpvan the victory in their group. The GPS trackers functioned reliably in the test and fulfill all their purpose. For those who value independent power and temperature monitoring, the prothelis is the best choice. However, the cheapest comes the salind.