Testing diode

This blogs about testing diode we done in practical.

first we were told to draw a picture of a diode and identify anode, cathode and current flow dircetion.
                                          The direction of current flow is from anode to cathode.

I then had to measure resistance and position ammeter to 2K ohms and test diode from anode to cathode and cathode to anode. Both readings were both infinite.Then without changing range I checked voltage supply in my ammeter by connecting it to another and was reading 0.6V this was not enough voltage to push electrons through bindery layer because 2K was to low to turn on the diode.

Since 2K wasnt able to read anything the range was now changed to the diode setting on the ammeter and did the test again. Anode to cathode its reading was .54v and cathode to anode was infinite. These reading show that current flows through only one way because the gate will not let current go threw unless its a zenzor diode then it will bleed out excessive voltage so consumer/s dont blow.

We now had to build a circuit with a diode and resistor using a circuit board. When we had made the circuit we had to measure the voltage drop across the resistor which was 12.7V and same for across the diode which was 0.6V, then measuring amp flow through the diode which is 0.01V then measure voltage at supply which was 13.39V. Then add resistor and diode which is 13.35V. This shows in a circuit whatever the voltage supply is the consumers in the circuit have to add up to the same or voltage must be used up by consumers before returning back to battery supply. Now we had to change the resistor. The new resistor was 4000 ohms, now measuring across the resistor for voltage drop which was 12.8v then measuring across the diode and it was reading at 0.57V. I then had to measure the amps through diode which was 0.0 Amps. This indicates that the voltage is slightly up but resistor is to big for the circuit and it restricts any current flowing into the diode.

We now had to test an LED with a meter in the diode test position both ways anode to cathode 1.8v and cathode to anode 0.0v and compare its voltage drop to a diode. This shows if you need a big voltage drop, you would use a LED and if you need a small voltage drop, you use a diode.

Now we had to build a circuit with the LED. When done we measured voltage drop of resistor 11.3v then measure voltage drop of diode 2.1v then the amp flow through LED .01Amps then adding both resistor and diode result 11.3+2.1=13.4v. Comparing this circuit with the circuit with no LED, the voltage drop without LED is lower 0.6v than the circuit with the LED 2.1v and amp flow is the same in both circuits.