Yes, but current gain in this case translates as voltage gain, so to quote you...A darlington has a high current gain, but the same voltage gain as an ordinary single transistor. Voltage gain has nothing to do with beta.
Beta affects the input impedance.
I don't think so.
If you need a common emitter design with a high gain value, the transistor is the first place you start, followed by the Rc/Re ratio and the impedance of the load it is feeding. It is possible to have a common emitter design alone that will have a gain of 1000, but not with a conventional transistor with a beta of 300.
I haven't done much design work with common base, so I have some boning up to do.
Interesting, most of the designs I was used to seeing at Collins Radio was Common Base, followed by Common Emitter, followed by Common Collector. Low input impedance, low output impedance with reasonably high gain and frequency responce values. Most of the frequency ranges for these kind of amps were 10hz to 16Mhz, or 70Mhz amps.Sorry for the double-post but I didn't see the 2nd page until now.
A BC107 transistor has a gain-bandwidth product of typically 300MHz. It will still have plenty of current gain at 30MHz. It will have plenty of voltage gain at 10MHz.
Gusmas doesn't want a cascaded common-base driving a common emitter because it has an extremely low input impedance.
Instead he wants a cascode pair:
Why do you think the other configuration is more desirable? Common emitter designs are usually meant to feed medium impedance loads, while the common base design definately has a low impedance input.
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