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Storm detector circuit

This storm detector circuit project it's in fact an receiver tuned to 300 kHz designed to detect the crackle of approaching lightning.
To increase sensitivity of this storm detector circuit you must use a long wire antenna.
A bright lamp flashes synchronous with the lightning bolts indicating the proximity and intensity of the storm.
The flasher is biased to not flash until a burst of RF energy, amplified by the 2N4401 (Q1), is applied to the base of the 2N4403(Q2).

Adjustment of storm detector is very simple : adjust the potentiometer until the flashing is stopped .
When storm detector it's adjusted, the lamp will occasionally flash when big electrical motors or appliances switch on and off and an approaching storm will give quite a show. Adjust the pot with no antenna if lightning is nearby.
Electronic parts required by this electronic project are : L1 10mH; L2 330uH; R1 180k; R2 3.9k; R3 22k; R4 2.2k; R5 2.7k; R6 47 ohmi; C1 680pF; C2,C3 0.01uF; C4 0.005uF; C8 100uF ; C9 1uf; D1 1N914; Q1,Q3,Q4 2N4401; Q2 2N4403; R10(pot) 20k.

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Circuit Diagram: 
Storm detector circuit


In the text it mentions the 2N3904 applied to the base of the 2N4403. But, the 2N3904 is not indicated in the circuit diagram or parts list. So, where does it go? Or is this a misprint? If so, what is the correct location of each amplifier?

Is not 2n3904, is 2n4401

I constructed this project using PN2222 and 2N3906 transistors, hand wound L1 and L2 on salvage green cores (.68 dia)from the junk box. I wind toroids using my L checker until I have the proper inductance. I use a super bright LED for the indicator. Works GREAT ! But couldnt get it to function using an indoors aerial...I intend to add an RF AMP in the front end...but intil then a ten foot lead to the outside works ok.