Archive for February, 2011

Cooling the Linksys E3000

A short time back I was shopping around for a new router. After some comparison shopping I decided on the Linksys E3000. (UPDATE: Read more on this at Cooling the Linksys E3000 – Part 2 – Inside the box)

However, I was having issues with my Wii randomly dropping off the wireless network. I started troubleshooting and accidentally happened on something that bothered me: This router got HOT. By hot I mean I checked it with my infrared thermometer and I got a reading of 61C from the bottom of the router. That’s well above it’s operational temperature rating of 40C.

First, a note on my configuration:

  • DD-WRT v24-sp2 (12/19/10) big (e2k-e3k)
  • 2.4ghz  and 5ghz access points, both in use
  • A single gigabit device on the wired lan.

I had a good deal of network activity going at the time, so I took most of the devices off the network, powered off the router for about 5 minutes, turned it back in and checked again. No measurable difference in temperature after about a  minute of operation.

My concern was that the router was simply too hot to continue operating like this. I was afraid of chipset failure.

I started in on a mod idea, with a couple of points:

  • The router needed to be cooled quietly
  • The router needed to be cooled in a way that wouldn’t void the warranty in case I ended up RMAing it.

I initially thought of driving a fan from the DC-in connector, but the barrel shape made it difficult to come up with a clean mod, and at 12 volts, it could get a little noisier than I wanted it to be. I wasn’t using the USB port, and that’s an easy 5v supply to a fan, clean and easy.

So I started with a simple USB-to-fan cable. Pulling the 5v supply off the USB port and to a fan connector was easy, and after a quick check with the multimeter said it was good to go. It worked great, but I found out that unfortunately none of the fans I had lying around ran at 5v; they were all 12v fans. I would have to buy a fan for this.

I figured a 120mm fan would give me good air flow at a low noise rate, along with covering most of the bottom of the router. A quick search turned up a Coolerguys 120mm USB fan. A 5v fan with a USB connector to boot. Oh well, I still get to keep my cable for another project :)

So I ordered the fan. It arrived quickly (not quickly enough, I was impatient! ;) ), and I started in on making it look nice.

Removing the grill from the fan was the first step, and it came off easily with a #2 Philips screwdriver.

I had some adhesive foam feet lying around from something else, and cutting them in half and stacking three gave me a nice fit with the finished feet measuring 25x20x28mm.

I added some 4mm rubber feet to the bottom of the fan to give it intake room, and test fitted it. It couldn’t have worked out better. The fan fit neatly under the router and ran quietly — I could barely hear it even when the room was completely quiet. The 4mm rubber feet allowed enough intake room under the fan, even though the fan could have easily moved more air with more of an intake space.

The result? A reading of 30CThat’s a 31C drop in surface temperature! Of course, if you do this, make sure the fan is blowing up into the bottom of the router; not down.

The Wii? As it turns out, it was in a spot where it got terrible signal to begin with. A wired adapter fixed it’s issue.

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Synology DS211j drive led light bleed fix

Recently I bought a Synology DS211j NAS for storage. A pair of 2TB hard drives in RAID-1 make for roomy storage, and this NAS is rich on features for it’s price, and it only supports up to 2TB drives.

I ordered the NAS with 1 drive initially, then got the 2nd one shortly after. One minor thing I noticed fairly quickly is how the light from the drive 1 led would bleed into the drive 2 indicator.  It made it look like the light was on when in fact it was off.


The 4th LED is the drive 2 light. There's no drive 2 installed.

The 4th LED is the drive 2 light. There’s no drive 2 installed.

Despite it’s compact case (or maybe because of it) the DS211j is very easy to work on.

The case cover slides off for easy installation of the drives. Here you can see the NAS with the cover removed and one drive installed. The top drive slot is drive 1, the bottom is drive 2.

Single 2TB drive installed

Single 2TB drive installed

I had to see how the LED light output was being delivered to the front of the case, for this, I removed the front bezel from the case cover. It removes very easily using a #2 Philips screwdriver.


Next I placed the front bezel on the bottom to see where everything lined up. It was quickly evident where the light “leak” was occurring — the plastic divider that Synology was using between the LEDs simply wasn’t present between the drive 1 and drive 2 light channels.


After some thought I came up with a solution: Isolating the light channels using electrical tape.

I carefully put the electrical tape on the light channels and carefully cut to fit. The result:


I test fit the light guides over the LEDs.


And that’s it! After reassembly, the drive 2 LED was nicely blacked out. I did install my 2nd drive today and it looks great. I can now easily notice the drive LEDs blinking independently of each other.

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Reading the date code on your Dell laptop battery

It’s a well-known fact that Li-ion batteries have a shelf-life, and the OEM warranty on batteries is typically only a year. This is because not only do the cells degrade over time, but they also degrade over use. If you’re having trouble with your laptop battery, it’s often worth a minute or two to read the date code on it to see if it’s premature failure or old age. You can read more about Li-ion cell life here if you’re interested.

Every Dell part has a PPID sticker, and the Dell part number is part of that number. Along with the country of origin, the date of manufacture, and some other information. I’ll explain three of these fields. Here is a sample PPID sticker from a Dell battery:

Reading the date code on your Dell laptop battery

You see three fields marked in the photo:

Country of origin: The first field (blue field) in the photo indicates the part’s 2-letter country of origin. In this case, Korea.

Part number: The second field (green field) in the photo has the Dell part number. In this case, UD265 (the leading zero is omitted if present). Knowing the part number makes it easier to order a replacement battery. :)

Date Code: The fourth field (red field) in the photo shows the parts date code in three digits:

The first [hex] digit indicates the year of manufacture. 1-9 for 2001-2009 respectively, 0 for 2010, A for 2011, B for 2012, C for 2013, D for 2014, E for 2015, F for 2016, etc. (Note: See Chris’ comment below.)

The second [hex] digit indicates the month of manufacture. 1-9 for January through September, respectively, and A-C for October through December.

The third [hex] digit indicates the day of manufacture. 1-9 for day 1 through 9 respectively, and A-V for 10-31.

This battery was made January 5th 2008.

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Restoring the Network-Manager applet in Ubuntu

So you’ve noticed the Network-Manager applet is missing from your notification area in Ubuntu and you can’t connect to your wifi or cellular network. Now what?

Here’s a few tips to get it back, based on Ubuntu 10.10:

1) Make sure Network-Manager applet is installed

Open Applications > Ubuntu Software Center
Type ‘network’ in the search box and hit enter.
Locate ‘Network Manager’ in the application list and make sure it has a green check mark next to it.

2) Make sure Network-Manager-Applet is set to run on start-up

Open System > Preferences > Startup Applications and make sure the box next to Network Manager is checked.

The next two tips are slightly modified tips provided from UbuntuGeek:

3) Make sure Network-Manager is managing your connections

Open the terminal and type:

gksu gedit /etc/NetworkManager/nm-system-settings.conf

change the “managed=false” to “managed=true” and then save it.

then in the terminal type:

killall nm-system-settings

and then reboot.

4) Re-add the notification area to your bar:

right click panel>add to panel>Notification Area

5) Two bugs reported to LaunchPad involve this. Bug #577678, and #589362. Regarding #577678, a user suggested this fix:

Open a terminal and type:

gksu gedit /etc/network/interfaces

then check that the file has only this 2 lines:

auto lo
iface lo inet loopback

Delete all the others then reboot.

6) You may also want to try restoring the panels to default.


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