Nice video!! You can still improve the selectivity and sound Use this same circuit given in this video! just some modifications 1st tip - By putting the 'speaker with box' (no need to open) close to the coil as much as possible without distorting the sound (too close causes overdrive input) buttt the capacitance will be more sensitive, you have to adjust it very slowly and carefully (because of the increased selectivity) you can try another one method if other is problematic 2nd tip - use a separate smaller coil 1/5th or 1/6th of the main coil wound on the same tube (5mm to 10mm gap) should be connected between the (crystal radio) 'audio out' and 'audio in' of the amp !you have to adjust carefully! Good luck :-)
Yeah, I was on a bit of a Rush re-listening binge at the time. That LM386 finally ended up on a home-brewed PCB, with volume and gain control pots, plus a bass boost switch, which is about as far as I can take it. I was impressed that it handles high impedance circuits like this crystal set so well and the computer output too. It gets used often as it is now for amplification tests of different radio designs. At present I am tweaking a very successful and simple TRF radio design (which does not need a long, exterior wire antenna like this one), and working on making an amplifier for it from scratch with a Darlington transistor and a hacked, small transformer to obtain the right impedance matching to an 8 Ohm speaker. It will never be as good as a pre-made IC like the LM386, but what can you learn if you don't experiment? LOL! I'll upload a video when it is finished. :D
Nice video!! You can still improve the selectivity and sound
Use this same circuit given in this video! just some modifications
1st tip - By putting the 'speaker with box' (no need to open) close to the coil as much as possible without distorting the sound (too close causes overdrive input) buttt the capacitance will be more sensitive, you have to adjust it very slowly and carefully (because of the increased selectivity)
you can try another one method if other is problematic
2nd tip - use a separate smaller coil 1/5th or 1/6th of the main coil wound on the same tube (5mm to 10mm gap) should be connected between the (crystal radio) 'audio out' and 'audio in' of the amp
!you have to adjust carefully! Good luck :-)
Thank you for the suggestions! I will look into that on my latest project.
Analog Kid by Rush! An excellent choice for testing the amplifier.
Yeah, I was on a bit of a Rush re-listening binge at the time.
That LM386 finally ended up on a home-brewed PCB, with volume and gain control pots, plus a bass boost switch, which is about as far as I can take it. I was impressed that it handles high impedance circuits like this crystal set so well and the computer output too. It gets used often as it is now for amplification tests of different radio designs. At present I am tweaking a very successful and simple TRF radio design (which does not need a long, exterior wire antenna like this one), and working on making an amplifier for it from scratch with a Darlington transistor and a hacked, small transformer to obtain the right impedance matching to an 8 Ohm speaker. It will never be as good as a pre-made IC like the LM386, but what can you learn if you don't experiment? LOL! I'll upload a video when it is finished. :D
interesting
Does it require any battery or power source to power up the LM386 in this circuit?
Yes, I used a 7.5 VDC source on this one. Check out the schematic at 0:43 it is there, towards the top right.