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Well, it depends on the load resistor. Typically one would take an RFC whose impedance is at least 10 times greater at the operating frequency. So for a 50ohm load this is L>1.6uH. But take care and dont take the L too high. Then the self-resonance frequency becomes too low, and above this frequency the supposedly high impedance of the RFC is in fact smaller than expected! The type of inductor depends of the application you're using. The higher the output power, the greater the inductor core needs to be to prevent saturation of the core!
If yoy choose to resonate the thing out, you can take smaller L and make it resonate with the coupling capacitor at 5MHz. This gives better harmonic suppression. The Q-factor of the load circuit defines the amount of suppression.
Class c is a modulation method used in rf amps. Think of a transistor with the base being driven by the carrier and the collector being modulated by the signal. A cool animation is at http://www.williamson-labs.com/480_am.htm
class c is a common emitter amplifier works in off region and needs only ac signal to let it operate on/off and according to application needed it's usually used in AM
an amplifier is said to operate in class c when an output signal is produced for less than 180 degree of the input signal. as we progress from the letters A,B,AB,C,D,G the amount of time for which load current is produced reduces.
in class A the output signal is produced for the whole input signal. this type has the least efficiency. in class B the output is generated for 180 degrees of the input signal. class B improves the efficiency but the tradeoff is that u get a highly distorted signal (one that has half the signal clipped :!: ). so as u progress through the letters the efficiency increases and the distortion increases too.
class c amplifiers are used for high power applications (communication). class c is used because of its high efficiency. we dont care about the distortion it produces because the output of the class c amplifier is not the information we are transmitting. its the carrier signal that carries the information.
I think you should find this in many book about designing RF circuits. Such as " Fundermentals of RF circuit design" or some book. I don't remember now but I will send the address to you later.
I think you should find this in many book about designing RF circuits. Such as " Fundermentals of RF circuit design" or some book. I don't remember now but I will send the address to you later.
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