Author: Dave Farquhar

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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How to use Deoxit D5

Dave Farquhar Hardware
How to use Deoxit D5

Retro computer enthusiasts and computer technicians either love or hate Deoxit D5. There’s no middle ground with it. But I think the hate comes from people misusing it. Used sparingly, Deoxit D5 seems like a miracle cure. Here’s how to use Deoxit D5, and when.

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How to remove wire insulation without cutting wire

Dave Farquhar DIY
How to remove wire insulation without cutting wire

It’s hard to strip the insulation off wire without cutting or nicking the copper beneath.It’s frustrating when you cut through the wire, but nicking the wire is bad too. The danger when you do that is you weaken the wire. And then the end may snap off someday, causing a bigger problem. So here’s how to remove wire insulation without cutting the wire.

If you consistently cut through the wire, check your tool. Some wire strippers work with all types of wire, and some work with just one. If you have the kind for one type of wire, get the other one too, and learn to recognize which is which.

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Looking back at the Challenger disaster through Gen-X eyes

Dave Farquhar General
Looking back at the Challenger disaster through Gen-X eyes

It’s January 29, 2021 as I write this. Thirty five years after the Challenger disaster. I was in math class when I found out it happened. That was a little unusual.

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