Electronics Made Easy - a Complete Introduction to Electronics - Martin Denny [17]
g) A production plan or instruction must be produced if the device is produced outside your immediate control. Remember to include a complete component list, circuit and layout diagrams and provide the components or specify the suppliers. Note that delivery times can be a significant factor.
Post Production Evaluation
The device must be thoroughly tested to confirm that it complies with the original specification. An inspection or test report must be prepared on the device showing the measured parameters, and then signed and dated.
In many cases a Declaration of Conformity will be required which will state the relevant British or European standards the device conforms to. It may be necessary to confirm this by testing (in a standards laboratory) and can prove very expensive for small quantities. Another requirement is that the designer or manufacturer retains a conformity file on the device. This document must contain the specifications of all components used in the device with a listing of the appropriate standards.
The Operating Manual
The report or operating manual will be required in almost all cases. The manual has two functions, to allow the safe operation of the equipment and to impart enough information to facilitate repair.
The manual should have a logical format starting with a contents list and ending with any additional information enclosed in an appendix. If the manual is produced for a specific device the appendix could contain the Test Report and Declaration of Conformity. A typical manual format is shown below:
CONTENTS: This section should list subject headings in page number order
(include drawings and figure numbers).
The manual format is similar to a report format except the summary and authorisation sheet is not added to the front of the manual, and conclusions and recommendations are omitted.
Glossary of Terms
Planning
It is useful once the final design solution has been selected to produce a plan of the process showing activity against time. The critical path should be marked on the diagram, ie those processes which must be completed before the next stage can begin. It may be useful to flowchart the process as an aid to determining the critical path.
WORKSHOP PRACTICE
I started building electronic equipment as a hobby at the age of 12. As the circuits became more complicated the time spent de-bugging equipment exceeded the build time, if they worked at all. The easy explanation might be faulty components or a poor initial design or possibly even a mistake in reading the circuit design, but in practice the fault usually lay with the idiot using the soldering iron.
When soldering components to a printed circuit board or each other a good electrical and mechanical connection must be achieved. It does not follow that more solder or more heat is better in fact the reverse is true. A good soldering technique relies on preparation.
1.0 Useful Equipment
Before starting any build a selection of tools must be obtained, and an area prepared to carry out the work.
1.1 The Workbench
Any table or existing workbench can be used as long as you feel comfortable sitting at it. It should be faced with hardboard, glossy side up, coated with several applications of varnish. The workbench should be close to a 13A socket outlet preferably at worktop height or power can be fed via an extension lead. The work area should be well lit possibly with an additional desk lamp.
1.2 Hand Tools
When making or adapting a case or enclosure the usual mechanical tools are requires ie drills reamers files etc. It is generally better to carry out this work away from the electronic workbench as it should be kept as a clean area.
The list below represents the bare minimum tools required to start:
1) Long nosed pliers large.
2) Long nosed pliers small.
3) Side cutters small
4) Cable Stripper
5) Craft knife