Author: Dave Farquhar

How to use Excel VLOOKUP

Dave Farquhar Office
How to use Excel VLOOKUP

VLOOKUP is a very useful tool in Excel but can be difficult to get right. Here’s how to use Excel VLOOKUP, including an example and what to do when it doesn’t work right.

VLOOKUP is a useful tool for data analysis in Excel, especially merging data from multiple sources. It’s a frequent question in job interviews for business analysts and other jobs that handle data.

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What does CVE stand for? How do you fix one?

Dave Farquhar security
What does CVE stand for? How do you fix one?

What In Information Security and Information Technology, CVE stands for Common Vulnerabilities and Exposure. It is a standard identifier for tracking vulnerabilities in computer software. I’ve only deployed updates to fix about 800,000 of them, but that experience taught me a little bit about working with them.

The CVE database is maintained by MITRE, and there are about 100 CVE Numbering Authorities (CNAs) who assign them. The CVEs themselves don’t include a lot of detail, but they serve the purpose of providing a common identifier that vendors and security professionals can use to track each unique security flaw.

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Make a picture ledge for your vintage computer

Dave Farquhar DIY, Retro Computing
Make a picture ledge for your vintage computer

Some Youtubers, including Casual Retro Gamer, use picture ledges to keep their vintage computer systems on the wall when they’re not using them. You can buy a picture ledge, but they’re easy to make, too. And if you make them, you can make them whatever length you want.

A picture ledge is a small, J-shaped shelf that mounts on the wall, normally used for displaying art without having to use a bunch of hangers. But their size works well for vintage home computers and game consoles too, allowing you to store and display them.

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Windows 10 audio not working? Try this.

Dave Farquhar Windows
Windows 10 audio not working? Try this.

My power flickered and my computer restarted. Everything seemed OK, but then I noticed my audio wasn’t working. If your experience Windows 10 audio not working suddenly, especially when you haven’t changed anything, here are some things to try.

Sure, the problem could be a driver, or your volume knob, or a cable problem. But if your audio stopped working suddenly, it’s more likely that Windows just decided to change outputs on you, and that takes about 10 seconds to fix.

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How to remove sticker residue

Dave Farquhar DIY
How to remove sticker residue

As a retro computer hobbyist, former bookseller, and landlord, I’ve had to deal with stickers a lot. It’s not always easy, but it’s possible to remove sticker residue from almost anything. Even paper. Yes, even paper. I’ve removed stickers from inside books and left the page completely undamaged. Here’s how.

Removing sticker residue often requires use of several different techniques including heat and chemicals. My favorite is rubber cement thinner, as it will even remove sticker residue from paper, but different surfaces require different options.

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Atari 800 video cables

Dave Farquhar Retro Computing
Atari 800 video cables

The standard for video output on 8-bit computers is there was no standard. Well, oddly enough, a bunch of companies did something super similar, but there are enough gotchas that you have to be careful. At least Atari sidestepped the problem. Here’s my experience with Atari 800 video cables, which also (mostly) applies the XL and XE variants. And you can use the same cable with other machines in a pinch.

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What CVSS is and how to use it

Dave Farquhar security
What CVSS is and how to use it

What is CVSS? CVSS stands for Common Vulnerability Scoring System. It is a method to express the relative strength of vulnerabilities compared to each other. It’s a common statistic in computer security, especially in the field of vulnerability management.

There are two versions of CVSS in common use. The major difference is version 3 allows you to account for environmental factors to adjust it, but both of these versions have one significant weakness.

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7805 switch mode replacement

Dave Farquhar Retro Computing
7805 switch mode replacement

One of the best things you can do for heat dissipation in vintage computers and consoles is replace the 7805 voltage regulator with a modern switch mode replacement. Here’s why that helps and where to get one.

A modern 7805 switch mode replacement regulator runs cooler than the original 7805. This reduces the need for heat dissipation and helps other components, such as capacitors, last longer.

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ETL file: What it is and how to open or read it

Dave Farquhar Windows
ETL file: What it is and how to open or read it

The C:\Windows\Logs directory has tons of useful information in it, but it’s all in the obscure ETL file format. What’s an ETL file, why did Microsoft switch to this format, and how do you open the file to read it?

ETL stands for Event Trace Log, and they contain information from kernel events generated by Tracelog. Windows uses them because they are more efficient than logging in plaintext, and you can open ETL files in Event Viewer, but it’s also possible to convert them into XML, CSV, or plaintext for troubleshooting.

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Why do capacitors fail?

Dave Farquhar Hardware, Retro Computing
Why do capacitors fail?

Bad capacitors are the bane of generations of consumer electronics. They plagued early 90s Amigas and Macs, early 2000s PCs, and cheap hardware even today. So why do capacitors fail? And how can you tell when a failed capacitor is a problem?

Capacitors fail when the electrolyte dries out, or when the gas inside them builds up to a point that it opens a safety valve and the electrolyte leaks out. A good capacitor takes decades to dry out, but a cheap capacitor can leak within a few short years.

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