A quick guide to choosing the best amplifier
Here are some expert tips from our technical partner E&I on choosing the best amplifier for your needs.
This is the first thing you need to consider. Don’t choose an amplifier with a higher frequency range than you need. Why? Because you’ll be paying more than you need to. RF amplifier costs increase significantly with frequency.
E&I specifies the frequency at the range over which the amplifier will produce rated power. So once you’ve worked out the upper end of the frequency that you need, choose the series of amplifiers that exceeds that by the smallest margin.
On the flip side, you’ll also have to check that it doesn’t operate too far below what you need as you’ll be paying for unwanted bandwidth.
Number two on our list is power level. E&I rates all its amplifiers at 1 dB compression. As with frequency, you don’t want to choose an amplifier with a power level that greatly exceeds your needs. An increase in power level also means an increase in cost. When E&I say that an amplifier is rated at 100 Watts (eg the E&I 2100L ) that means that you can run it at 100 Watts, 24 hours a day, 7 days a week, in a continuous mode or any other that your application requires.
For a lot of applications, voltage might be a more important factor than power. E&I calculate the voltage from the power level and the impedance. The output impedance of all E&I amplifiers is 50 Ohms. But remember, the voltage across your load will depend upon the impedance of your load and must be calculated from that.
Class of operation
Last on our list of considerations is class of operation. E&I offer both Class A and Class AB amplifiers. AB amplifiers are low cost and more efficient, but they do have more harmonic distortion than the Class A amplifiers.