Abstract: A strain gauge load measuring system includes a pair of strain gauges mounted on each of one or more load supports, such as the axles of a vehicle. The strain gauges connect in a DC bridge circuit. A multiplexer comprises a pair of analog switches which alternately apply the voltage from respective bridge output terminals to an AC coupled amplifier, as a square wave voltage of amplitude equal to the difference between the voltages on the bridge output terminals. The amplified square wave voltage is applied across a meter as an amplified DC signal proportional to the DC bridge output signal, by a demultiplexer incorporating a further pair of analog switches cooperating with low pass filter elements. The demultiplexed DC signal across the meter is compared by an operational amplifier, having positive feedback for hysteresis, with the voltage on a variable voltage divider to determine when a threshold load value has been reached.