# LC circuit simple problem

#### kav

Joined Dec 24, 2010
4
hi I'm new to this site and also to circuits. I am working on something which involves me putting together an LC circuit with an output. So here is the situation:

- I have a DC battery of 6 volts and 1.3 amp
- I have a capacitor of specific value and an inductor of specific value
- I have no resistor because my wires are thick and I want at least 1 amp running through my circuit.
- I am trying to convert dc to ac as you can see.
- I followed the schematic from this link: http://www.walter-fendt.de/ph14e/osccirc.htm
- however, where do I put the output. Let's say i wanted to add a speaker so I can hear the note that the frequency makes. where would i connect the speakers to?
- also, a side question: does an ideal LC circuit create sine waves? or Square waves? if square waves, then i may have t opost another thread about to conert it into sine.

okay thanks, I would really appreciate this because i have spent literally weeks trying to figuring out such a small thing (well the whole LC circuit i mean) and i was getting quite frustrated that no website explains anything about the output of an LC oscillator circuit.

#### shteii01

Joined Feb 19, 2010
4,644
I don't think this is realistic.

I can be wrong, but I think what you should be looking for is multivibrator build using either transistor or operational amplifier.

#### #12

Joined Nov 30, 2010
18,216
The speaker would be connected across the inductor, but the resistance of the speaker would stop the oscillations very quickly. You can see on the page you posted that the output is a sine wave, but this circuit is not an oscillator. It is a momentary thing. Only lasts a part of a second.

#### kav

Joined Dec 24, 2010
4
Thanks for the replies,
ok so if this is a momentary thing, is there a way i can modify it by adding something or should I go with shteii01's idea with the multivibrator. Also, for the use of transistors or op amps, what values should I be looking at in a data sheet in order for it to do its thing. I'm looking for a specific frequency thats and woul dI still be able to use the same capacitor and inductor? or do I need more of the same values? or different values for a different circuit in order to get the same frequency? Thanks.

#### thatoneguy

Joined Feb 19, 2009
6,359
See This section of our e-book (accessed through the bar at the top of forum).

#### kav

Joined Dec 24, 2010
4
oh nice. but does it matter what frequency the ac source is? so if I used my capacitor and inductor for the specific frequency lets just say 10hz will it be affected in any way by the frequency of the ac source which lets just say 100hz. If it doesn't affect it then thanks because you've cleared up a lot for me. i just need to find out how to make an easy inverter.

#### thatoneguy

Joined Feb 19, 2009
6,359
i just need to find out how to make an easy inverter.

I'd suggest reading the e-book from beginning to end before continuing. There may be solder together kits available, designing one is a very large project.

There really isn't an "Easy" Inverter, assuming you want 12VDC to 120VAC. 80W-100W (peak) inverters are available for under \$30, far cheaper than anything DIY. The fact they are relatively small for their power does not mean they are simple.

#### kav

Joined Dec 24, 2010
4
ok then maybe this is not considered an inverter: i jsut want my dc battery to convert to ac with the same current and voltage. but i want it at the specific frequency that comes from my inductor and capacitor. I'm kind of on a time constraint I tried reading tutorials and watching uni lectures from the start but its just way too much to do a small thing. thats fine i guess i'll search elsewhere for help. thanks.