Mobile Network Signal Strength
To successfully send SMS messages the VanSecure control unit needs a certain minimum signal strength.
On the mobile phone the signal strength between it and the network is often shown as a bar chart. The VanSecure control unit communicates its current network signal strength to the mobile phone, and the mobile phone will display this value on the battery voltage indicator button when you tap this button. The button reverts to the battery voltage display after a short delay.
The signal strength is given in dBm (decibels per milliwatt) and is always a negative number. The larger he number the weaker the signal is and the closer it is to zero the stronger the signal. Antenna powers of less than -90dBm (from -90dBm towards -115dBm) will not produce reliable SMS transmissions.
It is often desirable to locate control equipment low down in the caravan under the dinette or near the battery, and this is not always the most favourable position for acquiring network signals. For that reason we can supply antenna extension cables which allow the antenna to be mounted a distance away from the control unit where the RF reception is better.
After adjusting for improved signal strength allow half a minute to pass before reading new signal strength information.