The relationship of Amplifier vs Power vs Frequency

[SHEN PEI]

I'm litter bit confuse on this, someone please advice! Thanks! 

[elix]

it depends on the load.

[audioguru]

I think the power output of an amplifier at a certain frequency depends on the design of the amplifier.
The amplifier could have terrible low or high frequency response.

[walid]

Hi guru
I can use SWCAD III to see the freq responce of a C-E transistor amplifier circuit,
But I want to know how are calculated or how is expected during the design process
Can you please explain to me
thanks

[audioguru]

Hi Walid,
Small signal transistors like the 2N3904 and BC547 have a frequency response up to 300MHz, so stray circuit capacitance limits their high frequency response if the resistors have a high value.

Power transistors like the old 2N3055 have a poor high frequency response which is extended with negative feedback.

I have never designed a high frequency radio amplifier and I can't remember what was taught many years ago.