Author: Dave Farquhar

Gzip vs Zip

Dave Farquhar Software
Gzip vs Zip

Zip and gzip are two similarly named utilities, and they perform similar functions, but they are unrelated. They also have slightly different use cases. Let’s take a look at gzip vs Zip.

Simply speaking, Zip and gzip are implementations of the same compression algorithm for different operating systems, so they are similar but the file formats aren’t compatible. Zip originated with MS-DOS, while gzip originated with Unix-like operating systems, notably Linux.

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Which side of an outlet is hot?

Dave Farquhar DIY
Which side of an outlet is hot?

While an outlet or electrical appliance will work if you wire it in reverse, it’s a safety issue if you get it wrong. So which side of an outlet is hot? In this blog post, I’ll tell you which side is hot, then tell you a silly story to help you remember it.

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Crystal Palace, St Louis

Dave Farquhar St. Louis
Crystal Palace, St Louis

The Crystal Palace in St Louis was a short-lived but legendary night club. It predated Gaslight Square, but moved west on Olive to join the up-and-coming district as it grew in popularity. The move benefited both. During its heyday on Gaslight Square, it was a combination saloon and 300-seat theater.

The Crystal Palace only operated for about 16 years, but it put St. Louis on the map, attracting national acts. Its mix of Victorian architecture, a cobblestone sidewalk, traditional lights, and antique decor inside is still widely imitated.

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Are password generators safe?

Dave Farquhar security
Are password generators safe?

You probably only have to ask the question twice to get two opposite answers. Are password generators safe? As a security professional, I’ll explain the problems with password generators. Then I’ll tell you why I use them anyway. Most importantly, I’ll tell you how I use them safely.

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Three prong plug wiring diagram

Dave Farquhar DIY
Three prong plug wiring diagram

If your plug breaks and you need to replace it, you can get replacement three prong plugs at a hardware store. But it usually comes bare, without any instructions. So, I’ll write some for you. Here’s a three prong plug wiring diagram if you need it.

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The killer POKE for the Commodore PET

Dave Farquhar Retro Computing
The killer POKE for the Commodore PET

When I was a kid, computer science textbooks taught a language called Basic. They explained various commands, including POKE, which changed values in memory, or on a chip register. The books went out of their way to explain that you can’t harm a computer with a command, even a POKE. But it turned out there was an exception–the infamous POKE 59458,62 on the Commodore PET. The infamous killer POKE.

The killer POKE, POKE 59458,62, sped up the Commodore PET 2001’s video output at the expense of degrading the video quality. The tradeoff seemed worth it, except it could damage the machine over time.

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Keep pipes from freezing

Dave Farquhar DIY
Keep pipes from freezing

During the winter months, frozen pipes can be a problem. Fortunately they are preventable. There are several things you can do, both temporary and semi-permanent, to keep pipes from freezing. They’re all pretty cheap and easy and worth doing.

Frozen pipes are most likely to happen when the temperature drops to well below freezing and stays there for a sustained length of time. But a bit of heat and/or water movement is enough to keep indoor pipes from freezing.

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Picking a setting for your model railroad

Dave Farquhar model railroading
Picking a setting for your model railroad

I struggled for a couple of years trying to decide on a time and place for my train layout. I was afraid of locking myself into a specific time period. What if I chose the 1950s, then decided I wanted to run trains that were older than that? Fortunately, the answer for picking a setting for my model railroad came kind of out of thin air, once I thought about it some more.

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What is a 169 IP address?

Dave Farquhar Servers and Networking
What is a 169 IP address?

If you’ve been around computers long enough, you know an IP address that starts with 169.254 usually means trouble. But what is a 169 IP address, what does it mean, and how do you fix it?

A 169.254 IP address is called an APIPA IP address. Your computer receives a 169 APIPA address when it can’t get an address from the DHCP server.

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How many outlets can be on a 20 amp circuit?

Dave Farquhar DIY
How many outlets can be on a 20 amp circuit?

There’s no official rule regarding how many outlets can be on a 20 amp circuit. And there’s no official rule about how many outlets can be on a 15 amp circuit either. But there are guidelines you can and should follow to avoid unnecessary breaker trips. And there’s another rule that’s much more important than the number of outlets.

The National Electric Code has no rules regarding how many outlets you can daisy chain off a single breaker. But generally speaking, it’s best to keep the number below 13 because of average current draw.

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