would this work?

[-=GST=- Nemisis (cs/cz)]

would this work for an electronic tuning device, not this is literally two pictures merged into one in a hope that it might work.

 

[John Sorensen]

what is ic1?

j.

 

[-=GST=- Nemisis (cs/cz)]

LM386 audio amplifier.

 

[JimB]

Ok, so the main circuit is a super regenerative receiver.
The variable capacitor to tune it is maybe OK.
What frequency is this receiver intended to work at?
The sketch of the variable capacitor infers something out of a broadcast receiver, be aware that if the receiver is intended for VHF, the capacitor will be too large if it came out of a long/medium wave radio.

But, the "varicap diode"!
What you have sketched looks like another varable capacitor, which is fine if you are trying to put a small capacitor in parallel with a large capacitor to give a "fine tune" or "band spread" tuning control.
But a varicap diode it is not.
Varicap diodes look much like othe diodes, a small cylinder with a wire out of each end, (OK there are variations on this, but lets keep it simple for now).

You could use a varicap diode in the position shown, but the circuit would be a bit more complex than shown in your diagram.

What are you trying to achieve?

Jim GM3ZMA

 

[-=GST=- Nemisis (cs/cz)]

its a FM radio, i know it works coz ive seen the desing and tested it, but i want a fine tuning device to make it able to get better reception. i got it from a book i found on the internet and i just mixed them together where it was supposed to go (which this in place of just a variable capasitor) i have never seen a varicap diode so i didnt know if it was right even thought it was clearly labeld in the book as one. if this is not the correct way of doing it is there any other simple way of making fine electronic tuning and/or a larger bandwitdh for the FM electromagentic spectrum?

 

[-=GST=- Nemisis (cs/cz)]

any ideas at all??

 

[JimB]

OK lets try this for starters.
If you make up this circuit and connect it in parallel with the tuned circuit in your radio, it will give you a fine tune facility. The components values I have suggested should be OK for a VHF (100Mhz ish) radio.

Jim GM3ZMA