Impedance Matching Question

[froteros]

Hi All. I hope this is the appropriate forum to ask this. I needed some basic advice about impedance matching. I have an RF amplifier with 50 ohm output impedance, capable of generating 400W output power at 500kHz. I am trying to deliver this to a 12 ohm load.

I looked online and figured out that I need to match the impedance of the amplifier to the load. My question is what is the best way to achieve this? Would it be possible to simply use a capacitor and inductor and put an L section to the output of the amplifier? I saw that online stores have very cheap capacitor and inductors that is rated for very high voltages.

If that is not going to work is it possible to buy any transformers that would do that? For instance I saw that there are many cheap 220v-110v voltage converters, which should have 2:1 coil ratio. So in theory that should convert 50 ohm to 12.5 ohm and matches to my load. Will these work at 500 kHz as required for my application? Or are there other type of transformers that I can use for this purpose (there are many many types of transformers and I got confused which ones are suitable for impedance matching)?

Thanks a lot for the help.

 

[davenn]

hi there
welcome to EP

what is the 12 Ω load ? an antenna ?
50 Ω to 12 Ω is a pretty horrible mismatch a 4 to 1 BALUN would do the job but at that low fre1 its gonna be physically big
An LC type antenna tuner would also do the job

You should probably really be talking to broadcast engineers to see what is done commercially

cheers
Dave

 

[JoeM]

I doubt he has a 12 ohm antenna, because making it into a 50 ohm antenna would be both easier, and better than trying to match his amplifier to 12 ohms. 500 KHz?