How to make an Oscillator
Oscillators are used in order to produce an alternating current especially in radio frequency. This frequency can be used for radio transmission. I have made some tutorials and introduction about oscillation/oscillator. You can check them out here. For me there are two ways to build an oscillator. The first one is using a capacitor feedback to the transistor and the second one is by using a crystal oscillator. And I will use the latter part.
To build your oscillator, you need to choose a crystal oscillator depending on what your desire oscillating frequency is. Note: It is one of the advantages of using a crystal oscillator - less computation for frequency output, and more accurate oscillation. In this circuit I used a 36MHz crystal oscillator. There are lots of tutorials out there on how to bypass a transistor, you could check it out. So before we assemble our circuit we need to buy the materials.
Materials Needed:
This is what my circuit looks like, I used EagleCad to make this schematic diagram.
Resistors (1/2 Watt)
|
Capacitors
|
Inductor
|
Transistors
|
Crystal Oscillator
|
1k ohms (2pcs)
10 ohms
4.7k ohms
47K ohms
33k ohms
|
0.01uF (3 pcs)
10pF
20pF
7.5uF
10-25uf (Trimmer)
|
* Use with magnetic wire SWG # 22
10 "long
16 "long
|
2N3904 (2pcs)
|
36MHz
|
This is what my circuit looks like, I used EagleCad to make this schematic diagram.
Crystal Oscillator Circuit
This is the actual circuitry:
Actual Oscillator Circuit
So that's it, you now have an 36MHz oscillator.
Notes:
- In order to make the Inductor, cut the required length of the magnetic wire specified and then wound it on a ¼ "diameter core. You can use a ¼ "drill bit for guide.
- As what you can see the inductor at the right is stretched. It is because after I placed it on a PCB. I tested it if it is operating at its maximum power transfer, and after some tweaking this is the look of my final circuit.
- Lastly, I also added a capacitor (the one at the right-most). Since I used this oscillator as an input signal to my next stage system. I placed a capacitor because as we all know it blocks DC signal, and I do not want it to distort my system, either if it is coming from my oscillator output to my next stage system or vice versa.
0 comments