Leon's Weblog

November 18, 2012

Getting Cash in Argentina

Filed under: Personal — Leon @ 10:10 am

XOOM During a recent trip to Argentina I discovered that the most effective way to get money from a US bank account is to send it to myself via money transfer. Sure ATM machines are ubiquitous but they don’t all work with US cards and the ones that do charge all kinds of fees. The biggest disadvantage of ATM cards, however, is that the exchange rate used is about 4.5 pesos to 1 US dollar while the unofficial exchange rate in Argentina is about 6 to 1. This spread alone is enough to make it worthwhile to not use ATMs.

I used XOOM to transfer the money to myself in Buenos Aires and found it much safer and secure than going to the shady money exchange “cambio” places which may slip in fake bills. A quick search online shows that others have had similar experiences with XOOM and consistently received rates of over 6 Argentinean dollars to 1 USD. The process to use this service is fairly straight forward. After setting up your account (basically who you are and where the money is coming from) you send money to a “More” pickup location. The main detail is to make sure to spell your name (as the recipient) exactly the way that it appears on your passport because that is what is going to be used for verification. The transaction takes about an hour from the time the money is sent to the time it is available for pickup. XOOM lists many pickup locations on their site but the main one that I found to work is the “More” office in Buenos Aires on Libertad 1057 near Santa Fe. To pick up the money, you just need your passport and the transaction id number. After the first transaction, sending additional funds is easy because all the information is saved on your account. You can go to the XOOM site from your cell phone, repeat the last transaction with a few clicks and the money should be available for pickup by the time you reach the office. (more…)

September 25, 2012

My First “Apple” Product

Filed under: Gadgets — Leon @ 9:00 am

Nest Thermostat No it’s not the new iThing[Phone, Pad, Pod, etc…] and it’s not really part of Apple anymore. Its the Nest, a smart thermostat designed by former Apple engineers. I was looking for a replacement thermostat for my central air system that had a bit more functionality than say a light switch and this seemed like the simplest DIY solution. Nest can be controlled remotely via WiFi (+Android app) and learns your schedule as well as temperature preferences over time. It has motion sensors to tell when you are home and does nifty calculations like determining the time until a desired temperature will be reached. Installation was straight forward and it seems to work as advertized (still need to see if it will save me any money on my winter heating bill). The closest competing product is from ecobee but it costs a bit more. Honeywell, the market leader, is completely out of the running since the company does’t want their systems to be installed by mere humans. In true Apple fashion, Nest does not integrate with any other home automation system but there are rumors of some integration features coming in next year’s model. I’m looking forward to the day when my Roomba can tell the Nest to turn the heat up when it’s wheels are cold.

May 10, 2012

Organizing Cooking Recipes

Filed under: Cooking — Leon @ 12:00 pm

I have been looking for some time for a way to organize cooking recipes. Sure there are plenty of websites offering hundreds of thousands of recipes for any occasion but what I really wanted was just a simple way to keep track of the few dozen dishes that I actually cook. There’s always the simple old-school method of keeping an actual book but I’m too much of a nerd for that. I’m also too lazy to write out or type up a full recipe from scratch (with pictures, ingredient amounts, and directions). To get by, I have been using sites like FoodNetwork.com to save some recipes as favorites but was not able to save my own notes and modifications. Finally there was the inconvenience of going to a computer to find the recipe, print it out, and then go back to it to after cooking to save notes.

The solution for me is an Android App called My Cookbook. The key feature is that it allows you to import recipes from many popular sites and store them locally on your smart phone (the apps scrapes everything including the image when it is available). You can also create your own recipe in the rare case that you cannot find anything close online. So what I do now is gather a few recipes for a given dish, import the one that is closest to my liking into the app, and then tailor it to taste [note 1]. Then, when I go grocery shopping, all the ingredients that I need are already listed on my phone. This may not be the nicest looking app on the Android Market but, given its functionality, I think it’s a keeper.

May 9, 2012

Multi-Room Audio from an HTPC

Filed under: Gadgets,Personal — Leon @ 1:22 pm

One of the design goals for my media center was to include multi-room audio so that I can play the same music in both my living room and the terrace when guests come over. I had already setup an HTPC which contained all of my media and configured XBMC to play it nicely. The next stage in the project was to have a way to stream the music outdoors without adopting an entirely new system.


February 19, 2012

Hacking Power Cords

Filed under: Gadgets — Leon @ 1:06 pm

This topic may be obvious to electrical engineers but I though it would nice to share a personal DIY success story. A few days ago the power brick to one of my Logitech devices failed. The device was several years old and I couldn’t find a replacement power brick anywhere. The power specification for the device is 5V DC at 500mA and it takes a 3.5mm barrel jack as input. This characteristics are very similar to those of USB powered devices so I set out to find a USB to 3.5mm barrel jack adapter. Amazon sold one for $1.50 and I decided to try it out. The cable worked but was very short and flimsy (I didn’t expect much for that price anyway). Also, the barrel jack from the cheap cable didn’t fit snugly in the device.

The solution was to take the cord that came with the device (it was the right length and had a power jack that fit perfectly) and splice in a male USB jack at the other end. The cables inside a USB wire are color coded (Red is power, Black is ground) so once I matched those up to the barrel jack, the wire was good to go. A little solder and electrical tape to tidy up the splice and cheap 500mA USB power adapter for the outlet rounded out the project. (more…)

May 20, 2011

Designing an HTPC (part 2)

Filed under: Gadgets,Personal — Leon @ 11:18 am

This is the second part of the article on designing an HTPC. In part one, I described the hardware components and assembly steps that I used to build the device. Without the proper software and media, however, all you have is a pretty box that consumes power. In this part, I will revisit some of the design requirements that were discussed in part one and review the software that will make the magic happen. Although many of the tools listed are available for both Windows and Linux systems, I will describe the Windows editions (simply because getting the drives setup for all the hardware selected in part one can be a pain under Linux). Also, while the built in Windows Media Center may have some of the desired functionality it is often not the best choice available. (more…)

May 13, 2011

My Roomba

Filed under: Gadgets — Leon @ 1:46 pm

I have been using the Roomba 560 model for the past year and am generally pleased with its performance in my apartment. It took a few tweaks and adjustments at first but my Roomba and I have learned to get along quite nicely. The initial problems were solved by simply removing some obstacles on the floor and closing closet doors where the Roomba may enter and get stuck. The other solutions involved a bit more tinkering.

Cliff Sensors
I have a small dark area rug in the living room and the Roomba simply refused to clean it. It turns out that this is a common problem. The cliff sensors which are designed to prevent the vacuum from falling down the stairs are triggers by dark surfaces. I had to disable the sensors to fix this problem (this wasn’t a problem for me because I don’t have stairs). The options for disabling the sensors range from the elaborate but elegant solution of taking the sensor apart to turn it off to simply covering/taping up the 4 sensor externally with glossy white paper. I preferred the latter approach.

After a few months, the lighthouses (virtual wall) stoped working properly. Sometimes a lighthouse would unexpectedly turn into a virtual wall (stopping the Roomba from going into some rooms) and other times the lighthouse wouldn’t turn on or block the Roomba at all. I tried resetting all the virtual walls by taking out their batteries and turning off the Roomba (holding down the “Spot” and “Dock” button for at least 15 seconds) but that didn’t fix it. It turns out, the virtual walls like having fresh batteries to operate properly…

Battery Life
After about 6 months, the Roomba started acting a bit sluggish. It would need to go back to the base to re-charge before finishing cleaning the entire apartment. At one point a full charge would only last it about 30 minutes of operation. None of the resetting tricks worked so I called iRobot and was told that this is a known problem for this series. They sent me a new battery and a kit to upgrade the Roomba’s battery charging logic to prevent the problem from occurring again. So far so good. I was also told by customer service that this problem tended to happen when the Roomba was not used often enough (so the battery would overcharge).

Error 9
After about a year, the Roomba finally had to go on disability. It would erratically stop working and announce the dreaded “Error 9.” Roomba support documentation mentions that this error indicates that one of the bumper sensors is stuck or dirty. Unfortunately it can also indicate that the sensor burned out (as it was in my case). Luckily this is a common enough problem that some DIY engineers took to fixing it and one of them was nice enough to post a guide. This is a $2 fix if you do it yourself. (It looks like the guide no longer shows where to get the parts… I used Sparkfun.com)

Overall, I still think that maintaining the Roomba beats manually vacuuming and recommend it to anyone lazy enough to try.

Update 06/04/2013
After about 4 years of use, my Roomba has died once again. I called tech support, it was determined that the problem was again with the battery. Based on other user comments it seems like 2 years is the average lifespan of the Roomba battery so I guess this was to be expected. I ordered a new battery from iRobot and got a 15% discount as this was my first order of an iRobot accessory. I thought this was a good deal until I found a generic Roomba battery on Amazon for 1/3 of the OEM price. I would expect the generic battery to be of a lower capacity and quality (you get what you pay for) but it still makes more sense to replace a cheap generic battery every year than the expensive OEM model every 2 years.

The tech support guy tried to get me to upgrade to a newer model (at a slight discount) but I didn’t think it was worth it. Especially when you can upgrade the dust bin to the latest AeroVac model (with new brushes and filters) for only $70. I think it makes a big difference in the amount of dust that the Roomba picks up and make cleaning the vacuum a bit easier (single compartment bin). For some reason, this upgrade kit was only available in white in the iRobot store but I found the same 500 Series Upgrade Kit available in black on Amazon for the same price (with free shipping).

Finally, after messing around with glossy paper for a few months to cover up the cliff sensors (see above), I finally decided to take the cliff sensors apart to permanently disable them (see link above). Yes, this does void the warranty but the method demonstrated in the guide can always be undone and it really is much neater. After a while the paper taped over the sensors gets dirty and falls off requiring additional maintenance that I decided to avoid.

Update 06/05/2013
The Roomba had another operation today. After charging the Roomba directly from the external connecter (to charge a new battery), I noticed that the Roomba stopped charging when placed back on the base (with the external connector unplugged of course). It turns out that this charge connector on the Roomba has a tendency to break. The problem and fix is demonstrated here and here.

The problem is that the charge connector has a switch in it to detect when the Roomba is plugged in and this switch prevents charging from both the external connector and the home base at the same time. In fact, the Roomba won’t even return to the base station (i.e. dock) because it “thinks” that it is plugged in. Before going through the extreme measure of drilling the connector open to fix the switch (as illustrated in the fix above), simply try to use a thin screw driver and pull the flat metal lead towards the center pin of the connector (externally… opening no dis-assembly required). This may work for a while until the lead gets loose from vibration (at which point you may have to resort to the drastic measures illustrated… or order a replacement part on digikey.com for under a $1)

December 5, 2010

Designing an HTPC

Filed under: Gadgets,Personal — Leon @ 6:25 pm

I was hoping that 2010 would be the year of “Internet TV.” That, with the aid of set-top boxes. consumers would be able to integrate the functionality and content of a home office into the home theater. Several vendors proposed promising products including Google TV, Apple TV, Boxee Box, and Roku that would make this paradigm shift both easy and affordable. Unfortunately, the year is almost over and the promise was not to be. The promised products were released in time for the holiday season but are all plagued with limited functionality, lack of expandability, and proprietary content. For example, while the Boxee Box is great at streaming free Internet content from sites like YouTube, it has very limited functionality for organizing your personal media library and no storage space to keep it. Another daunting problem is that TV networks and on-line content providers like Hulu have blocked the devices’ access to their sites in anticipation of forming contracts similar to those that they have with Cable Networks. Ultimately it is the consumers that loose out on these long overdue features. This is why I decided to take matters into my own hands and build a Home Theater PC (HTPC) that would overcome the problems of the products available on the market today. (more…)

March 30, 2010

Streaming media library to PS3 with MediaTomb

Filed under: Personal,Software Dev — Leon @ 2:13 am

One of the goals that I had for my media center was to have the ability to directly play music and movies from my Linux Server. The PS3 provided half of this functionality by supporting wireless streaming and connections to UPnP A/V servers. MediaTomb filled the gap by enabling my Linux Server to stream my entire media library. Below are the details of my configuration and solutions to some of the issues that I encountered. (more…)

December 23, 2009

T-Mobile’s Touch Pro 2

Filed under: Gadgets — Leon @ 10:50 am

Touch Pro 2It’s been several years since I got a new phone. My old Eten M700 was starting to look a bit dated and the battery would only last for several minutes of talk time. T-Mobile’s Touch Pro 2 looked like the perfect replacement since I was already a customer. The TP2 immediately felt like a huge upgrade with a large bright screen, a battery that lasted several days with casual usage, and a 3G Internet connection. Also, unlike with earlier Windows Mobile phones, not much tweaking was required to get started.

Trouble With Time
For me, the biggest annoyance on the phone is that the time constantly got reset (see forum thread). This happened occasionally when the phone would automatically connect to the Internet to check mail or weather etc… This problem appears to be local specific and is caused by the T-Mobile network. Turning the phone’s data connection off/on would reset the time properly but this wasn’t a good solution for me (if you are checking the phone to get the time, how do you know if it is wrong). What worked for me was disabling all automatic clock updates by going to phone settings–>time zones.

Google Sync
Around this time Google had just released Sync which simulated a Microsoft Exchange server and enabled push e-mail and synchronization of contacts between Gmail and Windows Mobile devices. I found that this service worked well for e-mail but was not usable to synchronization of contacts. Every time a changed contact entry was synchronized, the system incremented the contact’s birthday by one day. It appears that this issue has very recently been resolved.

Screen Protector
The screen protector that came with the phone got scratched up pretty quickly. I also didn’t install it carefully enough so I ended up with a few air pockets that did go away after several months. I got the ClearProtector as a replacement. At first, I didn’t like the replacement. This protector was much softer that the one that came with the phone so I wasn’t sure if it would last. Also, applying the protector required wetting the clear plastic to activate the adhesive (I thought that was a bit unorthodox since we are putting moisture on a electronic device). The worst part about it was the amount of bubbles (several large spots and many tiny dots) that resulted when I first applied the protector. However, after a few days of use, I started to appreciate this design. Because the protector was softer it gave the phone a better tactile feel. Also, the material was permeable, so after a few days, all the bubbles disappeared and the screen became crystal clear. The best part is that, after a month of use, there are no visible scratches on the protector either.

Car Navigation
There is some concern on web forums that the latest versions of TomTom don’t work on the TP2. All I can say is that it works for me just fine (and it would have been a deal breaker if it didn’t).

Useful Links
You may find the following links useful for setting up the phone:

Update 1/25/2010: I just updated the phone to Windows Mobile 6.5. The update is available free from T-mobile.

  • The biggest improvement for me was that the phone no longer forces locking the screen based on MS Exchange Server policy. The new eye-candy is nice but I appreciate WinMo 6.5’s added configuration options and back-end features for working with MS Exchange etc… much more.
  • I did notice the same memory-leak/performance issue as a number of other users (memory usage jumps to over 80% after a few hours of usage. Setting the registry key HKLM/Software/HTC/ResProxy/ShareMemSize to 0 as discussed in this thread seems to have addressed the problem.
  • I’m indifferent about WinMo 6.5’s honeycomb start menu; however, I don’t like the amount of junk application that T-mobile put there with this ROM. I deleted the extra application shortcuts from /Windows/StartMenu/Programs using Resco File Explorer. Note that most of these shortcuts were marked as system files and hidden by default so you have to enable viewing system files in the File Browser’s options to be able to do this.
  • GPS still works (Google Maps, TomTom but not Bing) but the phone seems to have a weaker GPS reception than before the update.
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