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The oscillator tank is L1, C2, C5
Energy is taken out of the circuit via C3 and is amplified and fed in by T1 collector.
Is this a superregenerative receiver?
How does this circuit select the desired frequency? via the tunable capacitor?
An amplifier oscillates when it has positive feedback. Transistor T1 is an RF amplifier and C3 applies positive feedback to it.
A simple regen receiver is overloaded by strong local stations and since it has poor selectivity then it will probably pickup a few strong stations at the same time. A strong station will be over top a weak station.
There is no way a BC559 transistor can drive a speaker. if your schematic showed a power supply voltage then we can calculate how hot the BC559 and the speaker get. Both might instantly burn out.
EDIT: A superregen is really an AM radio that picks up all the Amplitude caused noise heard on an AM radio. It can pickup an FM station if it is tuned to a side of the signal then it "slope-detects" the amplitude changes as the signal frequency swings towards and away from resonance of the tuned LC. It is a horrible "radio".
The oscillation will be transmitted and will cause interference to others using the same frequency band.
You really want to avoid this.
Finding good explanations of how these receivers work is not trivial. They have complex modes of operation and you often find either extremely complex descriptions by people who *might* understand, overly simplistic descriptions by people who might *think* they understand, but very few that leave you feeling you really know more than you did before you started.
I think this page does a reasonably good job. I don't claim to have a great understanding, but this page at least tries to hammer things through my skull.
Oh, how are you with valves?
The schematic is missing a solder dot at the base of T1. It should be obvious that T1 operates as a common base amplifier since C1 grounds its base. T1 is a variation of a Colpits oscillator.Is T1 what configuration is T1 connected, common base or common emitter? Does the signal go down or up through T1, referring to the circuit? If T1 is off, does that mean oscillation stops? Does this circuit have an envelope detector?
Modern schematics do not need a dot at a T junction for connection but do at a crossIs T1 what configuration is T1 connected, common base or common emitter? Does the signal go down or up through T1, referring to the circuit? If T1 is off, does that mean oscillation stops? Does this circuit have an envelope detector?