Everything for Electronics

Ideas/Tips/Inspiration

Can’t Keyboard? Use Morse Code Instead

A few months ago, I accepted a challenge: Design a way for people who can’t easily use a keyboard to create text for applications such as Word, OpenOffice, eBay, or Google via Morse code. It takes only two fingers to create them, and learning to send Morse code proves easier than learning to receive it, which requires much practice. See how I used a $10 Cypress Semiconductor CY8CKIT-059 MCU board to mimic a USB keyboard but without software drivers, code libraries, or special USB-interface ICs.

Transformer Based Power for Nixies

Nixies were introduced when vacuum tube hardware automatically provided the high voltage they require. These days, circuitry typically runs on five volts or less, so finding the +170V or so for Nixie anodes can be a bit of a challenge. Here are three transformer based ways to obtain that high voltage in line-powered semiconductor-based devices.

An Easy CATV Coax Antenna

A few years ago, we brought you a story about a guy building ham radio antennas from aluminum crutches. Now, he's using cable TV coax for his dipoles.

Static Discharge Helps “Cure” Audio Amplifier

After trying different things to troubleshoot an intermittent problem with my MicroBITX kit (multi-band, software-defined ham radio transceiver), it turned out static discharge was the answer to my problems

Battery Pack Failure Modes I Have Known

Keeping your batteries ready for action in your ham radio hobby is something we all have to deal with. How much does “memory effect” come into play with recharging? Does it really exist? Let’s look at some different failure modes and what might really be behind them.

Copper Cobweb Circuit Construction

Are you bored with conventional two-dimensional circuit layouts, or looking for a way to add an artistic flair to your next project? I’ve taken point-to-point construction style a step further by making it self-supporting, which opens up a wide range of physical circuit topologies. (Point-to-point construction usually uses supporting structures like terminal strips that are functional but not pleasing to the eye.) I call this construction style the copper cobweb. Here’s how to do it.

LEDs for Operational Status and Troubleshooting

Even when a circuit functions as it’s supposed to, it’s not always easy to tell what it’s doing. Plus, waiting for an output (especially if there’s a long delay involved) is not always practical. Conversely, if a circuit does not function, the only means to find out what’s wrong is to troubleshoot it with either a multimeter or oscilloscope. Wouldn’t it be great if the circuit itself could tell us more directly what’s wrong?

Death, Taxes, and Exposure to Electromagnetic Radiation

Short of living underground in the wilderness without electricity, battery power, or Internet, exposure to electromagnetic radiation can’t be avoided. The best thing you can do is look at the guidelines provided by organizations like the FCC and ARRL, and use a little common sense.

Restoring the Heathkit ES-400 Computer

It took me eight months of part-time work to restore all 168 pounds of a Heathkit “H-1.” I would like to share a few of the trials and tribulations I went through to resurrect this beast.

Keep Your Home Secure with Raspberry Pi

Surveillance is one of the most effective deterrents against crimes lke burglary and theft. The Raspberry Pi can be the foundation of a great DIY home security system.