David L. Farquhar on technology old and new, computer security, and more
Will a light switch work with no ground wire? Usually. Does a light switch need to be grounded? Not necessarily. Here’s why you normally want a ground, and what your options are for a light switch without ground.
For a normal light switch, the ground is a safety feature, not necessary for operation. You can leave that screw unconnected if you don’t have a ground wire, or if you have the wire but no screw on the switch, you can ground the switch another way.
I frequently get questions like, “How much mortgage can I afford on 100K?” Or any other amount. The amount doesn’t really matter; you can do the math on any annual salary or combination of salaries. The important thing is to do the math yourself. So here’s how to figure out how much mortgage you can afford.
Unix and Unix-like operating systems like Linux have a command called reboot. Like the name says, it reboots the system. Veteran Unix administrators insist the correct way to reboot a Unix system is to use a cryptic command called init 6. Are they just showing off, or is there a good reason for this? It turns out there is indeed a reason why one should worry about reboot vs init 6, and using the init 6 command can protect your system.
A transformer’s circuit breaker should trip within a few seconds for safety, if not faster. If your Lionel ZW transformer circuit breaker doesn’t trip reliably anymore, it’s time to source a replacement. Here’s how to find a modern breaker suitable for use as a Lionel ZW circuit breaker and install it.
Don’t be intimidated. This is a relatively easy project and costs less than $20. The hardest part is soldering two connections. But first, always run a safety check, and, on ZWs in particular, check for and replace any bad binding posts.
There are any number of materials you can use to make ties to fill the empty spaces underneath Lionel O27 track. But I think I’ve found the easiest of all. The materials are cheap and readily available and you don’t need anything special in the way of tools. Here’s how to make O27 track ties out of foamcore board.
Smoke detectors save lives, so it’s important to have them. But how many you have and where you put them is also important. If you’re going to go to the effort to install smoke detectors, you might as well install them right. Here’s where to install smoke detectors.
Intel had a hit on its hands with the 8080 CPU and its successor, the 8085. But then Zilog came along and stole its thunder with the compatible but superior Z-80. Intel needed to follow up with something a lot better. The 8086 was what they came up with. The advantages of 8086 over 8085 were numerous, and that’s why everyone knows Intel, and few people outside of retro computing enthusiasts and embedded systems engineers ever heard of Zilog.
Here are the major advantages of 8086 over 8085.
Tenable plugin 63155 and Qualys QID 105484 reference a high-severity vulnerability regarding unquoted search paths. Unfortunately the fix action tends to be a bit vague. If you’re looking for a way to fix the Microsoft Windows unquoted service path enumeration, you’ve come to the right place. Here’s how to fix an unquoted path for Windows services.
It used to be that chapter one of any book about computers explained RAM and ROM. Based on my conversations with computer professionals younger than me, it doesn’t sound like they do that anymore. So here’s RAM and ROM explained, by a guy who learned the difference in the early 1980s.
My favorite engine is the Marx #54 tin diesel lettered for Kansas City Southern. Unfortunately it has poor pulling power. Being a hollow tin body, it just doesn’t have much weight to it, making the marginal Marx motor even more marginal. Here’s what to do when a Marx engine can’t pull.