Hi friends,
Urgently need some advice in purchasing off the shelf RF amplifier for my application. I have to amplify a 25 MHz,( ~0.5 to 1Vpp) sinusoidal signal to ~12 Vpp in my experiment. This is needed to drive a electro-optic phase modulator operating at 25 MHz.
I have no background in electrical engineering, and do not quite know what would be the right kind of RF amplifiers for my application?

I thought I could use the Minicircuit's ZFL-500LN low noise amplifier. It is rated for ~24 dB gain. But then I found that max input it can amplify is only 50 mV pp. Beyond that the output was saturating. The max undistorted signal that I got from ZFL-500LN is about 1.5Vpp. This is a roughly factor of 10 less than what I was hoping for. I would greatly appreciate if you could suggest some alternative. Many thanks in advance.

I look forward to your reply.

Cheers,
James

 

Just taking a brief look at Mini Circuits, something like this might work:
http://www.minicircuits.com/pdfs/ZFL-1000VH2+.pdf

 

There's nothing wrong with padding down the input to bring the drive signal to less than 50mV. In fact, this often helps to make things more stable. You won't need all that gain, but it doesn't hurt to not use it all.
Eric

 

There's nothing wrong with padding down the input to bring the drive signal to less than 50mV. In fact, this often helps to make things more stable. You won't need all that gain, but it doesn't hurt to not use it all. You can then use a step up transformer to bring the output level up to where you need it, assuming you don't need more POWER than the amp can supply. If your source is 50 ohms, you might not have this option however.

If there's no compelling reason to use a low noise amp, though, there are much cheaper options to get the power gain you need.
Eric[/ You can then use a step up transformer to bring the output level up to where you need it, assuming you don't need more POWER than the amp can supply. If your source is 50 ohms, you might not have this option however.

If there's no compelling reason to use a low noise amp, though, there are much cheaper options to get the power gain you need.QUOTE]