Antenna Selector
By Enrique A. Wembagher, Argentina
hcdx web, 30 September 2002

This project was built to be able to experience with more of an antenna and also in turn to be able to have a system that offers security to the receivers, carrying out the discharge to ground of the antennas.

I suppose that many of you will want to already experience with another additional antenna to the installed; this selector gives solution to the situation it inconveniences of to unplug and to plug connectors losing valuable time.
The same one can be used as much as for longwires, dipoles, etc., although it could be special for longwires installed with different orientations.
The solution is very simple with a single switch, but I also kept in mind the security, because in these times "crazy" plagued of atmospheric storms, it can also happen that we receive discharges that for minimum that are they can end up damaging the circuits of entrance of the receivers, like Sony ICF-2010´s usually happens in those that many users burned for overload in the antenna to the transistors of field effect that are to the entrance of the reception circuit, without knowing that these they are damaged the receiver since equally it works but with a diminished reception.

The circuit that is shown is extremely simple and it works in such way that you can connect an antenna or other and also both (it is single question of experiencing) with the extra attaché that in position (OFF) of both switch, the antennas are connected to ground and at the same time they disconnect the receiver achieving the wanted security.
The materials are of easy acquisition and the switch can be of the type switch of "combination" that are used in the electric facilities or some other one that you possess.

I should indicate that the switch carry out the connection internally from an inverse way to the position of the switch (of this they don't worry), in the figure they are indicated pressed the switch in position OFF, which is the suitable one to leave to our receiver when we don't use it, this way they were the connected antennas to ground.
In position ON of the superior switch, will only be connected the ANTENNA 1 and the ANTENNA 2 it will continue connected to ground, the procedure to the inverse one will carry out it when they want to only use the ANTENNA 2.
You will be able to carry out the project to their way, that is to say placing the necessary connectors and switch, mounted in a plastic box or of aluminum and carrying out the connections preferably with coax cable, being housed in a comfortable way for their handling.
They should remember that it is indispensable to have a good setting to ground in all reception system to obtain a decrease of noises and to achieve good receptions.
For extra protection, add two diodes 1N4148 in output to the receiver.