An Obligatory Nerd Gift Guide

This post is just thinly camouflaged hucksterism to fill my Amazon affiliate coffers, although if you have a nerd on your holiday list it might be helpful. Links are to Amazon but often a quick Google will net a lower price. These are products I’ve bought and used in the past year which seem to be working well for me, although as with all things YMMV…

• Weller WESD51 Digital Soldering Station
  I love this thing. Makes soldering easy and quick instead of a chore.
• Metro Vacuum ED500 DataVac 500-Watt 0.75-HP Electric Duster 120-Volt
  Fun and useful. I’ve used it to clean a number of PCs and other electronics, inflated air mattresses (not sure if that voids the warranty or not) and blown out a variety of filters. Even used it to clean the window screens.
• Saleae Logic USB Logic Analyzer
  There are less expensive products that do the same thing, but the software is well done and it works flawlessly.
• TP-Link TL-WN721N 150Mbps Wireless N USB Adapter
  This is my go-to adapter when troubleshooting other people’s connection problems. Seems to work perfectly with Linux as well.
• La Crosse Technology BC-700 Alpha Power Battery Charger
  Just a neat charger, tests batteries, conditions them, etc.
• Imedion AA 2400mAh NiMH Rechargeable Batteries, 4-Pack
  LSD (low self discharge) NiMH batteries, which means they stay charged longer before use. Some of our digital cameras will not work with ordinary NiMH batteries but do with these.
• SiliconDust HDHomeRun Dual High Definition Digital Television HDHR3-US (Black)
  We finally cut the cord (or the Satellite link) this year. Hooked up to our HDTV over the air antenna it pulls in free broadcast channels. Windows 7 sees this as two TV tuners on the network and will record programs as well as stream them directly to a computer.
• Roku HD Streaming Player
  We have a Roku hooked up to every TV (720p only, you need the next model up to do 1080). Works great with Netflix and Amazon, ok with Hulu+, lots of free channels, etc.
• Ticket To Ride
  A really fun board game that does not go on forever, has easy to learn rules and, well, trains!
• Zombie Dice
  Quick and easy, fun for kids who like zombies.

If you love me, here are a few things I’d love to find under the tree, but I’ll probably just end up buying them for myself…

• The Art of Electronics
  I hear it’s a great read and my local library does not have a copy available.
• Rigol DS1102E 100MHz Digital Oscilloscope, Dual Analog Channels, 1 GSa/s Sampling, USB Storage
  My free 40 year old oscilloscope just isn’t cutting it anymore. I’m happy to accept a donation of a less antique oscilloscope though. I could also use a bench supply, signal generator, and…
• Makita MAC700 Big Bore 2.0 HP Air Compressor
  The cheap Husky from Home Depot really doesn’t have enough oomph for my needs.

Catching Up

Yes, I’ve gone through one of my posting dry spells lately. We’ve had a number of projects going and I just haven’t had the time or inclination. Here are some random pics that barely convey what’s been done.

Hippy handyman Alec cutting some formica for our kitchen counter. A long awaited improvement.

I did the window casing. It took me about 6 hours, which is why we hired Alec to do the countertop – would have taken me several weeks…

Inspired by the EEVblog, I tore down a Samsung monitor that had stopped working.

Two bad caps on the right.

One other bad cap. The monitor works now that I’ve replaced them.

We decided to hire Nathan to pour a concrete deck/patio to replace our dangerous rotten wood deck. This involved having a plumber reroute our old, installed by the previous alcoholic owners, gray water system. Unfortunately he discovered our septic was backed up…caused by several collapsed sections of Bermico pipe. So we had to get the excavator out here and have some work done. May have to get more work done…

That solved the concrete got poured. It’s the length of our house and about 15’ wide.

Henry wanted to paint his and Max’s room. That resulted in large amounts of paint everywhere.

We received a large wholesale order from Made in Oregon, but they specified earring cards different from those we use. So I had to make a die to punch holes in about 100.

Nothing fancy, hand operated. The right hand posts align the card. in concert with the hanger affixed to the back.

Perfect holes.

A pile of cards.

I started hacking some cheap digital calipers but I haven’t gotten far on that yet.

I’ve been playing with milling PCBs, wrote up a short post on my Taig blog. The above is a PCB for another PC remote control.

It came out well and was compact enough that I could mount it in an unused bay in the new living room HTPC with just a hole in the bay cover for the IR detector.

Computer I/O shield Experiment, Take 2

I just wasn’t happy with the experiment, so I tweaked the file a bit and milled a second one. This is on the back of the computer and nobody will even give it a second thought, but it was annoying me nonetheless.

Milling

Done.

Comparison, old one on top.

In place. I probably could have moved the USB cutouts over another .01” but it’s much better now.

Happy kitchen PC. Running Xubuntu.

Computer I/O shield Experiment

I recently came across a large pile of new in the box computer parts at a garage sale ("at pennies on the dollar", said I to my suffering wife). I ended up with a processor (Core 2 Duo, 2.2Ghz), 120 GB hard drive, 4 GB DDR2 ram, Antec case w/ power supply, all of which were hypnotically commanding me to make a complete PC.
So I looked around online for a cheap Socket 775 motherboard and bought one from Geeks.com. It was refurbished and I didn’t notice that the description stated “Cables, I/O shield and Driver discs are not included.”. The I/O shield serves several functions, blocking off excess airflow, grounding the I/O ports and most importantly, shielding RF noise (these are all the fodder for much debate on computer forums). This last become apparent as a buzz on the audio line when I hooked the PC up to the kitchen TV.
Small detour: Did you know that most flat panel LCD and plasma displays usually have standard PC VGA inputs? Yup, they are all waiting expectantly to be hooked up to a computer. You can watch online content (Youtube, Hulu, Netflix, etc) as well as streaming audio from your network or the internet. In most cases all you need at a VGA cable and a 1/8” audio cable. (leaving aside the subject of HDMI which has vexed me of late on our living room TV).
So I figured I would attempt to make an I/O shield. I have come across this problem (missing I/O shield) several times before so I figured that what I learned from the experience would probably pay off later on. I did learn several things, most importantly to not buy motherboards without the I/O shield. (Mom, I/O means “input / output”.)
   
I took a picture of the back of the case. That curve to the motherboard is not a camera artifact, the motherboard is warped. What did I expect for $20?

I cropped and tried to get the sides parallel in Paint.net

I brought the picture into Rhino and scaled it to suit the ATX standard (6.25” x 1.75” +/- .008”) for the I/O shield hole. Then I drew some boxes around the various components.

I generated the toolpaths in MadCam (an excellent CAM plugin for Rhino, which was generously donated to yours truly by the fine folks at MadCam.

Beginning the milling operations on the Taig CNC mill.

Almost done.

Attached to “sprues”.

Cut free and cleaned up. I spent some time deburring.

It didn’t quite fit in spite of being within the specifications. So I filed the edges a bit and got it into place. So my second lesson learned is to reduce the edge dimension by .004” on all sides. Still within specifications but with some wiggle room.

Not quite what I was expecting…Seems that I miscalculated or otherwise managed to locate the cutouts slightly to the right of where they should have been. This is with the motherboard shifted left as far as possible. I said it was an experiment…My third lesson is to take some other reference measurements, which I thought I could avoid by working from the picture.

But the USB cable fits in the connector so all is good. I may remove it and file the openings slightly larger on the left side, or I may just leave it. Maybe I’ll make a new one later.

So there it is. Hooked it back up in the kitchen and there is now an absence of buzz on the audio output.
UPDATE: I decided to try again with better results, link to post.

To LA And Back, Part 3

On our way back home.

Victoria drove us to the train station. LA traffic is wonderful.

Outside Union Station.

Henry had a Wetzel’s pretzel for lunch. He enjoyed it.

Coming back along the coast at high tide.

It was  a bit gloomy but beautiful.

Some lunch.

Another stop. The couple in the foreground live in Oakland and were coming back from LA. He works at a large US Mail distribution center in Oakland.

The guy walking towards me is on his way up to UBC to study for a masters in Forensic Psychology. His main field of research is surfer and skater culture.

The “horseshoe” curve between San Luis Obispo and Paso Robles.

That’s highway 101. The train is pretty high up on the hill.

Back in Oregon, so green. The train was late getting into Klamath Falls so we were able to enjoy views of Mt. Shasta. I had a long conversation with a sheep farmer from New Zealand as we wended our way through the cascades.

Goodbye parlor car. That’s Angelina, our porter on the left.