Based on this `manual` PCR machine I built a few weeks ago, the Light Bulb PCR machine uses a light bulb and an old computer fan as its heating and cooling elements: Instead of the switches pictured above, the unit is now controlled by an Arduino Uno, Code Available Here. It uses a thermistor (a resistor that allows more current to flow the more
Click here to download the full size of the above Circuit.
heat is available) to monitor the temperature of the samples. Here`s the schematic: The light bulb is run on 110 Volt AC, so the Arduino controls a relay which turns the lamp circuit on and off. Both the Arduino and Fan can be powered by USB or by a 12 V external power supply (which provides faster cooling rates). I was able to put both of the relay systems onto the Maker Shield (which is awesome by the way, if you arduino you should look into getting one). This is what it ended up looking like: In this model, the tubes are heated using a 150 Watt light bulb (though you could definitely go with lower wattage) and cooled simply by an old computer fan I had lying around from one of many PC cannibalizations. The timing of the machine is actually pretty solid - a 1 minute elongation with 25 cycles ends up being ~2. 25 hours. I`ll get ramp rates posted soon. I built this prototype out of 4`` PVC pipe for a few reasons: because there are many prefabricated attachments available, it`s easily available and has consistent diameter and because I have quite a bit of experience working with it. There are three layers in the system all based on one 4`` PVC coupling and held together with regular 4`` pipe. The top layer is concave and holds the tubes and thermistor near the light bulb. The middle layer holds the fan and light bulb in place. The bottom layer encases the control system and safety switch in case something starts to smell....
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: