| 摘要 |
<p>The device senses an abnormal condition in the region of a television set around the neck of the cathode ray tube, switches off the supply and sounds an alarm, thus reducing the risk of a tube implosion. The circuit consists of a low voltage relay driven by a rectified output transformed from the main supply. The relay has two sets of contacts, one normally closed connects the supply voltage to the television set. The other, normally open, connects the low voltage supply to an alarm. The alarm is either audible or a flashing light which is supplied with the correct voltage across a resistor fed zener diode. The relay is energised normally from the low voltage supply via a temp. sensor and or a smoke or flame detector. When the circuit is broken the supply to the tv is disconnected and the alarm activated.</p> |
