Posts Tagged ‘wireless’

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Script: Wireless Strength Polling/Logging/Graphing

Initially, I wrote this script to give me frequent feedback on the signal strength. This is useful when adjusting antennas to that sweet spot that give stronger signals; especially if you’re testing some homemade tinfoil parabolic reflectors! 😉 If you have a portable wireless device, like a netbook, you can ssh into your (wireless) desktop and run wireless-strength to get realtime feedback on adjustments to the access point’s antenna… assuming the connection doesn’t break. 😛 And, of course, you can just walk around running it on your mobile device to create a kind of wireless heatmap.

If you have gnuplot, you can also generate graphs from the data with ws-plot. This is me walking around my house with my notebook:

I started in my room (40% 🙁 ), which is where the first peak is – near the window. Left my room, back to 40%, peak near window again, then bathroom… 40%. The climb from 40-80% is me walking towards the TV room (PS3 lives in a solid 80% zone, at least!). Walked upstairs, got 100% in most areas (that’s where the Access Point is) – tried a bedroom, dropped to 40%.

Download the scripts and get more details here: https://github.com/izm/wireless-strength

Nerdy Ramblings

This script originated years back, but I recently tried using it on my laptop and it didn’t work! Unacceptable! The original parsed the output of iwconfig. But what showed up as “Quality=30/70” on my desktop, would show up as “Quality:4” on my laptop. COMPLETELY DIFFERENT. Even the character after “Quality” was different! o.O The output of iwconfig is driver dependent, which is why I looked to network-manager. I figured there’s probably a nice dbus command I can send to network-manager for that purpose – but I got tired of looking and decided to just parse output again. :/ Luckily, network-manager includes nm-tool. It’s certainly not a clean solution, but it works for now.

I also used updating rewriting the script as an excuse to get better acquainted with git – which I’m really liking.

Every time I do a bash script, I vow to do the next script in Python. I like Python and I don’t like Bash… but there’s a certain… nativeness or dependency-free elegance to bash scripts. Still, I hate writing them, and the next script’s in Python! 😛

DIY Wireless Booster

To access the Internet on my desktop computer, I must use wireless. Unfortunately, it’s about as far away from the access point as possible: opposite corners of the house and different floors. And the wireless card I’ve got in my desktop is a little old and pretty cheap. Basically, I’ve had to battle with a poor connection for years. Often, I would have to manually move the antenna an inch this way or that, try reconnecting, and repeat. I vented to my friend, Shirley, about my connection, and she said her friend was having similar issues, so Shirley recommended she make a signal booster. That’s something I’d been thinking about doing, and thought it was about time. I googled how to make a booster. Enter the Parabolic Reflector available here. I’m sure there are lots others, but this is the one I decided to try out.

Desktop antenna with booster

I made 3 of them. the first was made entirely with paper and tinfoil and it worked fine, but I figured I would try making a couple more with different materials: 2 different strengths of card. It’s good I did that too, as I ended up using 2 of them and giving the paper prototype to Shirley’s friend who most likely has better things to do than build paper parabolas. 🙂 (I, on the other hand, do not.)

Gluestick?  Check.  Scissors?  Check.

Access point hidden away, with booster pointed down slightly (towards my room)

What does it do? It turns your omni-directional antenna into a directional antenna with a stronger signal. The tinfoil does the radio wave reflecting and the shape (the parabola) just happens to be an efficient way to do that. Using this new direction, I’ve “pointed” the antenna on my wireless router towards my room – even on a bit of an angle through the floor. In my room, on my desktop PC, I’ve just pointed it horizontally in the direction of the access point.

Wireless signal strength over a few days

The results have been great. Without any home-made boosters, I received 25-35%, with one on the access point, i received 35-55%, and with one on both the access point and my desktop antennas, I’m receiving a pretty steady 62-68% (see the graph, above). I still receive disconnects, but it’s now much easier to reconnect… usually happens automatically on the first try – I don’t even have to do anything!

So if you’re having wireless issues, give it a shot! It certainly doesn’t cost much. 🙂

Ubuntu 8.10 (Intrepid Ibex) and Tablets

I just had to mention this: The latest version of Ubuntu finally supports input hotplugging. What this means is that you can plug in your tablet at any point and start taking advantage of its pressure sensitivity, etc. Previously, it would only work correctly if Ubuntu (the X server part of it) started with the tablet plugged in. Let me just say: OMG, I’ve been waiting for this for years! Seriously. I hadn’t been keeping up with every detail on the release (and I’m surprised I hadn’t seen mention of this yet), but I always plug in my USB tablet and run a quick test with new releases. This time, it actually worked! My test turned into a quick (and random) doodle:

How to Test

Plug in your tablet.

Run GIMP (included with Ubuntu by default).
Applications > Graphics > GIMP Image Editor

Enable Extended Input devices in GIMP.
Edit > Preferences > Input Devices > Configure Extended Input Devices

Find your tablet under the Device dropdown (mine is a Wacom Graphire) and select Screen or Window for the Mode. (It defaults to disabled.)

Create a new image, select the paintbrush tool and start drawing. To play with the features of your tablet, expand the Brush Dynamics section in the paintbrush options window (should be below the toolbox, where you selected the paintbrush). Here you can adjust things that pressure of your pen will control, like size and opacity. Fun stuff!

It’s not perfect (only works with the stylus – eraser doesn’t work without configuring), but it’s a HUGE step!! 😀 And the fact that this also includes the latest version of GIMP (2.6) makes this upgrade an absolute no-brainer for linux graphic-philes. 🙂

I found the new UI in GIMP a little strange at first, because I became so accustomed to the old one, but it is much better.

Upgrade Problems

Related to the upgrade, I lost wireless connectivity with my laptop upon doing it because the hostap_cs driver is used. I forgot about this issue that I had with previous releases and my super-cheap 1000yen wireless card. Blacklisting the hostap_cs driver and forcing the orinoco_cs driver fixed my problem again. The lesson: the upgrade wasn’t perfect and it should never be assumed that they will be – please backup your stuff! But do do the upgrade! 😉