FM radio reciever why connect output of antenna in the collector of transistor?

Thread Starter

xso111

Joined Oct 12, 2017
24
i was asked to build an fm radio reciever and found out this circuit design


why is the output of the antenna connected in the collector of the transistor? we were taught that the input of the transistor is at its base and the output is at its collector.

also side question where is the tuner located? because in some guides they say its in the oscillator(https://electronics.howstuffworks.com/oscillator3.htm) and others its in the rf amplifier(http://www.futureelectronics.com/en/wireless-rf-radio-frequency/rf-amplifiers.aspx) lets say i want my reciver to get 100Mhz which part of the circuit handles the actual filtering to only get that 100Mhz.

pls help im relatively new to this.
 

LesJones

Joined Jan 8, 2017
4,174
The transistor is operating in common base mode, The antenna is not connected to the collector it is connected to the emitter.
It looks like a regeneritive receiver design. This uses positive feedback so the circuit is near the point of oscillation to get more gain from a single stage.

Les.
 
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