The Southern Railway used check codes to confirm that the correct road number
was reported. You too can figure out the check code for any road number.
1. Take any diesel
road number. Add zeros to the beginning of the number if the it only had a
two or three digit road number. For example, road number 2750.
2. Add the first
digit, plus twice the second digit, plus the third digit and twice the fourth
digit. If doubling exceeds 9, like 2 x 7 = 14, then add the digits; in this
case, 1 + 4 = 5.
3. Sum the 4
individual numbers, then take the number in the "10" spot, the right most digit.
In this example, the sum is 12, the right most digit is "2". Subtract that
number from 10. For our example, this would leave you with "8".
4. Convert the number
into a letter using the following table:
0 = A, 1 = F, 2 = H, 3
= J, 4 = K, 5 = L, 6 = R, 7 = T, 8 = W, 9 = X
In this example, the check code for 2750 is "W".
Now you can look up
any number with this code form: