| 摘要 |
<p>The inside of a windscreen washer jet housing (D) has a transistorised circuit with a temperature dependent resistor, and a reference current resistor. The circuit draws a small DC current when the temperature drops below a set level, to keep the jet from freezing. the thermal output from the transistor can be used to heat one jet and the current through the reference resistor to heat the second jet. The small amount of DC current is too small to drain the battery when the vehicle is parked and does not cause any radio interference. An indicator lamp is parallel to the circuit and mounted on the dashboard gives the driver warning of freezing conditions.</p> |
