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You can hear weaker stations in night.
The scheme uses high gain low noise transistor BC547C to archive best sensitivity and signal to noise ratio.
When I was listening to a close by station I measured almost 1V of signal before the diode which is a lot for one transistor radio.
L1 and L2 are coils make a transformer with ferrite rod core (10mm diameter and 100-150mm length).
L1 contains multiple sections about 23-30 rotations of wire each.
L2 is one section: 4-8 rotations. I used 7 but you can find tune it to archive better results.
You choose one of the L1 sections using rotary switch or just soldering one of the wires. This way radio cavers the whole MW band frequency range.
Selecting L1 section works as rough tuning and adjusting C1 capacitor as fine tuning.
C1 is "duplex 443BF variable capacitor". It changes capacitance between 20 and 270pf. We use just one of 270pf sections.
If assembled correctly this scheme should work right away. Select a L1 section and slowly rotate C1 until you hear something. Repeat for each L1 section.
Sensitivity of the radio (how far you can hear stations) depends on good is your antenna, earth connection and time of day. Also please be aware, many electronic devices can cause electromagnetic noise. So try turn all devices close to your receiver.
You can make some measurement to check if amplifier looks good. If you measure current via R3 it should around 1.46ma. Voltage on Q1 collector should be around 3.6v