Transceiver polarity protector

DETAILED DESCRIPTION OF THE INVENTION One preferred embodiment of the basic circuit of the invention is illustrated in the figure where positive output terminal 12 of polarity protector 10 is connected to the positive power terminal 14 of mobile transceiver 16 and negative output terminal 18 is connected to negative power terminal 20 of transceiver 16.
These connections are made only once during the useful life of transceiver 16 and may be made at the factory, permanently wired by the user or at the point of sale, or independently installed in conjunction with an existing installation by the use of conventional detachable connectors.
In any case, the connection between transceiver 16 and polarity protector 10 is considered permanent and all subsequent disconnection of the transceiver 16 from battery 22 should take place at battery terminals 24 and 26.
To put transceiver 16 into operation in a new location, input terminal 28 of polarity protector 10 is connected to battery terminal 24 and input terminal 30 is connected to battery terminal 26.
No polarity need be observed during this operation.
If terminal 28 is there by connected to the positive terminal of battery 22, polarity sensing control circuit 31, consisting of semiconductor diode 32 and relay coil 34, is not activated because diode 32 blocks the current flow through relay coil 34 and relay arm 36 remains in the normally closed position shown.
In such a case, however, polarity sensing control circuit 37 is properly connected to allow activation of relay coil 40 through semiconductor diode 38, thus switching relay arm 42 from the normally closed position shown so that contact 44 is connected to contact 46.
This action applies the voltage on power buss 48, which is of positive polarity, to positive output terminal 12.
Negative output terminal 18 remains connected to power buss 50 because relay contacts 52 and 54 remain connected through relay arm 36.
If terminal 28 is connected to the negative terminal of battery 22, diode 38 blocks the current flow through relay coil 40 and relay arm 42 remains in the normally closed position shown