quick electronics designs


Posted on Feb 6, 2014

Snap all connectors on to the flat cable (a small vice will do the job). You get an instant male-male, male-female, female-female serial adaptor, plus a short extender cord. A must-have tool if you`re planning to play with serial ports. You can even put an extra connector for monitoring the RS232 traffic. Another nice tip sent by Randy Rhoade


quick electronics designs
Click here to download the full size of the above Circuit.

s: did you know that if you connected a null modem between the connectors on one of the ends, the Snake becomes a loop-back tester This circuit has been designed by Gabriele Bandini. His home is full of telephones, modems, and. kids. After a dozen of modem crashes, he decided to put an indicator LED on every phone plug to show to the family when the phone line is free. If you have a FAX and a phone on the same line, this circuit can show you when to make a phone call without disrupting an incoming fax. If you have an internal modem, this circuit will show you when it is on hook Note that this circuit is designed to work with italian telephones and that you need the written approval of your phone company prior to put something on the phone line. If you don`t have noticed it yet, I like to reuse hardware objects. This design brings new life to an old lcd alarm clock (but I bet it would work with LED types too). It is useful for a variety of purposes, from watering your flowers to (precisely) switch on the heating, the garden lights or even your christmas tree! The circuit cannot be simpler: the activating signal is picked up in parallel from the original buzzer (that can even be removed). When the alarm "sounds", the set/reset flip flop is SET. The flip-flop output is also connected to the RESET input, through a 10Mohm x 1000uF delay network. This means that, after the delay time (about three hours on my prototype), the...




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