How to construct a circuit on veroboard by reading the schematic. If you’re an experienced constructor, then you will just look at the schematic and start assembly. Experience tells you where to place components and use veroboard space to its best advantage. If you are a beginner, certain prerequisites are assumed. You need to be able to read the circuit diagram and relate to each component on the diagram, as it is wired onto the veroboard.You also need to be able to solder, and beware of the position and orientation of the board and components when working on it from the reverse side.
The circuit of the bench amplifier is chosen to represent this article. The notes for this particular circuit are in my test gear section. The schematic is shown below :
First a parts list is created.Below is the suggested parts list :
1 22k potentiometer (log)
1 1R5 ohm resistor 5% tolerance
1 10u 25WV electrolytic capacitor
2 330u 25WV electrolytic capacitors
1 100n ceramic capacitor 100V ( these small capacitors are usually rated 100 or 2220 or 400V)
1 LM386 linear integrated circuit
1 8 Pin DIL socket (optional)
First the components are collected and laid out. The blue item is a veroboard track cutter. A 1/8 inch drill bit can be used to break the tracks.
A suitable piece of veroboard is used. This must be large enough to hold all the components of the circuit. They are available in standard sizes, the piece below is 9 holes wide by 25 holes long and approximate dimesions 1 by 2.5 inches. Each of the horizontal 9 strips is known as a "track". A track is the same as a single wire running from opposite ends of the board.
If a track is broken, with a drill bit or veroboard cutter, then you have two non-connected wires on the same horizontal strip. Note that NO continuity exists across adjacent tracks. If this should happen, i.e. when cutting a track and a piece of copper "swarf" should accidentally bridge two tracks, then the design would be compromised and probably not work at all. Therefore take care when breaking tracks and examine the board after making each break.
Check that the veroboard is large enough. Loosely push all components through the holes (in any order). Leave at least a space of 2 holes between components. This will allow room for wiring and track breaks. A small vice may be helpful to assemble your circuit.
Work begins ! You do need to know how to read a schematic. The lines represent wires, the symbols are the components. How to read a schematic can also be found on my site, in this practical section, click this link.
To help identify components, these are listed here. Look at the schematic. The triangle represents the LM386. As 7 connections are used it makes sense to place the IC somewhere central, (see above picture), as tracks above and below the IC will act as the wires for the power supply.
Turn the board over, all component pins should poke through the shiny copper side of the board. All soldering and track cutting is also done on this side. You need a little soldering experience to begin with. If you are not used to soldering, then it is advisable to use a plastic IC socket. There are other advantages to using a socket, mainly if the IC should fail, it can be simply unplugged from the socket and replaced, no need to desolder and resolder. Remember that as the board is now upside down that the top and bottom tracks are reversed. If you turn it upside down and through 180 degrees then left and right are also interchanged. This must be born in mind throughout construction. If in doubt, turn the board back and forth and keep an eye on a reference point, say pin 1 of the IC, marked with a dimple or round spot.