Looking for antenna switch for my project

Hi people,

I have one antenna with frequency range 10 MHz to 300 MHz and another antenna with frequency range 300 MHz to 3 GHz.

Do you know any kind of antenna switch that I can use wtih my antenna?

thanks

Receive only?. If transmitter, how much power and how frequently will you switch (solid state versus Relay), hot switching or with RF power offf, etc.

Thanks for your reply.

These antennas are Just receiver.

You did not give enough specifications for the switch you want to use.
From all I can see you can use a manual toggle switch which will be lossier and lower-isolation above 0.5 GHz.
If you want to use a TTL-controlled switch, there are RF relays available, see e.g. OMRON. I used their RF relay for 5.8 GHz.
There are many types of switches, manual, electro-mechanical, etc.

You should specify what you need.

I need to do a scan between these two antennas because I am developmenting a spectrum analyser. So teh scan has to start with 10 MHz and go until 3 GHz, but I have two antennas to do with. So the scan starts with 10 MHz and when it arrives at 300 MHz, it must change of antenna. So I need a switch antenna. But I software has to control it because I CAN'T do it manually.

I am developmenting it in Labview. I saw some examples of PE4251 (Peregrine Semiconductor) SPDT switch.

thanks

Okay, now I understand better. You need a TTL-controlled SPDT switch in 50-Ohms. For a spectrum analyzer to be connected to two antennas, I would recommend to use a SPDT coaxial electromechanical switch with a TTL driver. Such switches have 50-Ohm connectors and a low loss and a good isolation.
Their possible disadvantage is a low switching speed, ~ 100 ms . If you need a faster switch, I mentioned OMRON RF relay which switches within ~10 ms.
You can certainly use semiconductor or MMIC switches which are faster but they have a higher ON loss and some a poor isolation. As your spectrum analyzer covers the frequency range of 10-3000MHz and power levels from 0 dBm to < -60 dBm, loss and isolation are important parameters.
As you will connect antennas to a sensitive spectrum analyzer, you may consider to add a limiter to prevent an overdrive by TV, FM and other high-power signals to get to spectrum analyzer.

For incidental switching, I agree to use an electromechanical coaxial relay. If the sweeps are very fast (covering 10 MHz to 3 GHz in one sweep) and the system has to operate for a long time, you may consider a solid stade (FET) switch. This requires you to do some intermodulation analysis.

PIN diode SPDT switches from 10 MHz to 3 GHz are difficult to get (I hope somebody will correct me if I am wrong).

http://www.hittite.com/content/docum.../hmc174ms8.pdf
The Hittite MMIC SPDT can cover from DC-3GHz:

Thaks again for your reply.

I saw some models of TTl-controlled SPDT switch in 50-Ohms, but how do they work? I need to change the antenna trought software. Can I do it?