Over the years I’ve either created or found small crib sheets or help cards that are useful to keep around the workshop for when the old grey matter lets me down. I’ve got a set of these all laminated (was a great reason to buy a laminator) and they are super useful.

Traditional resistor colour code chart

Logic gates and ICs

I created this to help when working with logic gates. It lists the six basic logic gates, their truth table, the circuit diagram symbol and a 74 series IC package that contains one or more of the gates.

Capacitor ESRs (Equivalent Series Resistance)

This table contains approximate values and is for guidance only. Identical capacitors even from the same manufacturer can have different values so this is should be used as a guide only. If a capacitor looks suspicious then refer to the manufacturers datasheet if available.

Ohms Law wheels

These have been in existence for years but I only discovered them recently and they are really useful. Maths isn’t my strong suit and these can be a real help.

Frequency / Period

When working with CPU and logic based systems you need to be aware of the access time limitations of certain components. I created this simple chart to give a rough cross-reference table of access times and frequency.