The Security Guard duty monitor below, shown in eight circuits at Digital Circuits - 1 are examples of logic circuits, i have converted them from the DOS Orcad to Orcad 9 and corrected some errors a few years back.
These circuits can be used for looking at the logic blocks or to learn. This product was built and sold to some firms many years back. Now these designs are best done with a PIC or Atmel chip. Here is the user manual
This circuit was done with CMOS CD40xx type of ICs. A RAM was used to store the Day/Time LED Status.
It was to monitor the Alertness of the Security Guard. Periodically the Unit will Buzz and Flash and the Security Guard has to press a Big Button to indicate he is awake, alert, agile and around the Unit.
All Green means fine, few Red LEDs means the Guard was sleeping or gone away from some times. All Red means Security Guard is missing. :-)
This is a slow scanner as process is slow, that way many analog inputs can be multiplexed and sent into one analog input of a D/A. In near real time systems a faster mux could be used or mux totally avoided. This was made in some numbers, so the pcb is better than others.
Just like rackmounts hold big instruments or computers, control panels small or big have to hold DIN Instruments, switches and annunciators to make it easy for the operator. The maintenance work also is simple from the backside. It can be kept near the machinery which it controls.
Some books that will help you learn electronics and are free too. Youngsters have a great wealth to find in the libraries. The Present day has made more information available online, it supplements the library resource.
What can never be found in libraries are found on the net and can be searched too. Here every individual shares his projects, ideas and designs and is not edited or moderated by any publisher or media.
These are nice Mini Reference Books that can build the Learning of EE students. Some interesting booklets - Circuit Protection, Control, and Measurement; Intro. to Wave-Generation and Wave-Shaping; Microelectronics and Test Equipment..
The Navy Electricity and Electronics Training Series (NEETS) was developed for use by personnel in many electrical and electronic related Navy ratings. Written by, and with the advice of, senior technicians in these ratings, this series provides beginners with fundamental electrical and electronic concepts through self-study. The presentation of this series is not oriented to any specific rating structure, but is divided into modules containing related information organized into traditional paths of instruction.
The objective of this textbook is to develop the RF circuit design
aspects in such a way that the need of transmission line principles is
made clear without adopting an electromagnetic field approach.
Therefore,
no EM background is necessary beyond a first year undergraduate physics
course in fields and waves as provided by most colleges and
universities. Students equipped with the knowledge of basic circuit
theory and/or an exposure to microelectronics can use this book and
cover the entire spectrum from the basic principles of transmission and
microstrip lines to the various high-frequency circuit design
procedures.
For
the advanced students the entry into this field is often pursued
through an electromagnetic field approach, while for the technologists
the basic circuit aspect embedded in Kirchhoff's laws is the preferred
treatment.
