I have been trying to make an AM radio over the last couple days and am very confused as to why this circuit is not working. I found the circuit on this website and I saw this video on this design. I have tried to copy it but it is not working. I have the output leads connected to a Sony speaker. It is a Sony VGF-WA1. 
Is the circuit diagram correct?
Is there a better AM radio circuit diagram that you know works?
simulate this circuit – Schematic created using CircuitLab
With components of 1 mH and 20 pF, the minimum frequency you'll be able to tune is about 1.125 MHz. And that's neglecting the self-capacitance of the inductor, which is probably quite significant.
For the US AM broadcast band, 535-1620 kHz, the de-facto standard part values are 240 µH and 40 to 365 pF. You might start by pulling these parts out of an old pocket radio to use in your circuit.
I made this back in 6th grade, about 1969. Make sure the diode is germanium. Add a 10k resistor as a load if no headphones in use. Use a long wire (several yards if possible) for antenna. When working good it may pick up many stations at same time.
Consider adding a earth grounded wire, it can greatly increase signal strength. Use high impedance headphones if possible (>32 ohms). You may need to add a 10uf capacitor in series with the headphones so only sound is output, not the tiny bit of dc the diode creates. Read @Dave Tweed answer as the variable capacitors range and inductor value is very important.
Here's a conventional schematic.
A 60' long, 30' high horizontal wire for the antenna and a buried water pipe for the earth connection, are a must. So is a germanium diode.
The coil may be wound on a 2" former (on-line calculators would be of help in determining the number of turns). The easier option would be an off-the-shelf 240 μH moulded inductor.
An air-spaced variable capacitor or a 'PVC gang capacitor' may be used for tuning.
Good results may be obtained using sensitive 'balanced armature' or standard 'high-impedance' phones.
A local medium-wave AM radio station would be of help in tweaking the setup.
There was too many signals interfering with the radio. I was very close to the internet router. When I moved to a different room it worked.
It will "work"- in the sense that an AM radio station will be heard- if the RF signal is large enough.
Use a good antenna, and live close to a radio station. And tune to the station.
Is there a better AM radio circuit diagram that you know works?
Suggest you have a look at:
From the title you can see that booklet is out of the dark ages.
For this kind of radio, you need a BIG antenna**, try for 100 feet of wire as high as you can get it, perpendicular to power lines if possible. Also, you need a good ground. Multiple earth ground rods at least 3 feet apart will do a good job. The antenna will serve you well when you graduate to shortwave, get a ham license, and start transmitting.
I built a similar radio in the 7th grade in about 1952. Mom and dad never suspected that I was listening to late night radio. In those days the diode was a little lead sulfide crystal that you had to poke with the whisker of a cat.
** Take appropriate lightning protection measures with the antenna and position it to avoid possible contact with utility power.
