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Crystal Sets | All about crystal sets with original images | |
Condenser Colour Code | The British colour code for marking condensers as they were known in bygone times, capacitors as we know them now. | |
Resistor Colour Code | How the early resistors were marked, body, tip and spot method. | |
Colour | Number | Tolerance | Voltage Rating |
Black | 0 | - | - |
Brown | 1 | 1 | 100 |
Red | 2 | 2 | 200 |
Orange | 3 | 3 | 300 |
Yellow | 4 | 4 | 400 |
Green | 5 | 5 | 500 |
Blue | 6 | 6 | 600 |
Violet | 7 | 7 | 700 |
Grey | 8 | 8 | 800 |
White | 9 | 10 | 1000 |
The first three bands indicate the value in micro-micro farads, the fourth the tolerance and the fifth the voltage rating. The forth and fifth bands commonly omitted. If the colours are split in different sides the "group of three" will be the value.
Note: In todays' terms micro-micro would be pico Farads,pF (10-12) and condenser translates to capacitor!
In the example shown the value is , 300 mmf (pF), a tolerance of 5% and DC voltage rating of 100 V.
Colour | Value |
Black | 0 |
Brown | 1 |
Red | 2 |
Orange | 3 |
Yellow | 4 |
Green | 5 |
Blue | 6 |
Violet | 7 |
Grey | 8 |
White | 9 |
Gold | Tolerance = 5% |
Silver | Tolerance = 20% |
The body colour gives the first figure, the tip the second figure and the spot the number of "0"s that follow. Sometimes a fourth colour is added to the end opposite the tip to show the tolerance. Standard resistors not marked will have a tolerance of 10%.
In the example, Tip = Green, 5, Body = Red, 2 and Spot = Orange, 000 So the value is 25,000 Ohms.
Sometimes the spot is placed as a band rather than a circular spot.
Note: Today's band value followed this earlier method.