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The Economics Of Bottled Water

Click on the above picture to view full size.

I posted the above comic strip because I think it sums up the reality of bottled water quite nicely. Now, while I consider this a tech blog, I also like to include useful posts on how the average joe can save some bucks. Simply from an economic standpoint, bottled water does not make good sense. Consider that the bottled water you are drinking can cost up to $10 per gallon versus pennies for tap water. Further consider that, in tests, bottled water is no cleaner than tap water.

For more reasons why you shouldn't buy bottled water, check out the following links.
Bottled Water Isn't Healthier Than Tap
Thirst - Fighting The Corporate Theft Of Our Water
Ditching Bottled Water To Go Green

Also, punch Bottled Water into Google to find many many more links related to the problems of bottled water.
Posted by PH on 03-06-2008 16:14:52 CST

With The New Year, It Is Time To Back Up Your Photos

Happy New Year Everyone! Seeing as how it is the start of the new year, it is also a good time to do some of the yearly maintenance chores on the PC and around the house. One thing I recommend you take some time to do is to organize and backup up your most valuable pictures. By valuable, I mean the ones that YOU find the most important. This would typically be pictures of the family, baby pictures, pet pictures, home pictures, etc. If you are like me, you probably have at least a couple of photo albums lying around in the closet somewhere. The great thing about film photos is that it takes a long time for them to degrade, so most of us just stash them away and ignore them. But, should you have a fire or some other disaster, those photos could be lost in a heartbeat. Fortunately, hard drive and removable media space has increased to the point where we can store thousands of photos on them quite easily and cheaply.

The first thing you will want to do is to get yourself a scanner if you don't already have one. If you need one, I recommend looking into an All-In-One Printer/Copier/Scanner. You can find an inkjet model for well under $100 these days, and the ability to make photocopies is handy. I have an HP model, and I can't complain about the performance. If you are on a really tight budget, ask your friends and family, most likely one of them has a scanner you can use/borrow.

Next you will want to set up the scanning software to store your photos in the proper format. I recommend using the highest color setting you can, the highest scan resolution you reasonably can (maybe 600dpi minimum), and then store your photos in either JPG or BMP format. These may not make for the smallest file sizes, but they are two of the most well supported file formats, making it easy to import and transfer the pictures later on. If you have some badly degraded or damaged photos, you may want to look into a photo restoration service. These services can often restore your photos to near-original quality and will generally provide you with a digital backup as well. Check your yellow pages for a service near where you live.

Once you have scanned in all of your photos, you will want to store them on removeable media. For the most bang for the buck, I recommend using write-once DVDs, commonly known as DVD-R or DVD+R. At 4.7GB per disc, you can easily save a ton of photos on one. Or, if you have less than 700MB of photos, a writeable CD would also be fine. To copy the photo files to the disc, you will need a program like Nero Burning ROM or Roxio Media Creator. I find Nero to be worth the money since I use many of the features, such as the DVD creation and burning tool, but if you are uncomfortable with the price, there are some decent free alternatives for simple file burning. One you may wish to try is CDBurnerXP. Once you have successfully copied your pictures to disc, I strongly recommend that you burn ANOTHER copy of those disc(s). I have seen more than one CD or DVD that I have burned go bad within the space of two or three years. Best to take the time now and make a second copy.

If you don't like the idea of burning them to disc, another alternative would be to store them on a flash drive. They are physically small, and seem to be more reliable for data storage. A good sized one will cost more money though. Or, if you are a real photo snapping maniac who prefers their photos in a raw format, you may want to consider an external USB or firewire hard drive for maximum storage capacity.

So, now you have all of your precious pics all safely backed up. BUT, they are not truly safe if they are stored in the same building as your original photos! This is something that people tend to overlook, but to have a really safe backup, it needs to be stored off-site of the originals. The best solution I know of is to take your media, and put it in a safety deposit box at your local bank. Many of us already own one, so simply stop by and drop it in there. It is not only safe from a major disaster, but it is also safe from anyone who might want to snoop your private data. Which brings up another subject, which is backing up your other important documents. I'll cover that soon in another article on PC backups, but remember that those too should be stored somewhere off-site and secure.

Finally, I imagine some of you are thinking to yourselves, "Why not store your photos online, using something like Flickr or Xdrive"? Well, you certainly can if you wish. However, be careful to read the terms of the agreement with these types of services to see who owns the content posted on their websites, and make sure that you don't post any sensitive information on these sites where they could become publicly available. My opinion is that if the service is free, you get what you pay for. And, who knows when they might shut down, and will you be able to get your data back if they do? Or, are you completely confident in their ability to protect your data from thieves? I recommend you use them if you wish for non-sensitive information, and keep the sensitive stuff locked away somewhere safe.

P.S. While you are at it, now would also be a good time to make a photo record of the contents of your home. If there ever were a disaster that destroyed your belongings, it could be helpful to have a photo history of all that you owned for insurance purposes. Take your digital camera and snap off pictures all over your house. Then copy those pictures onto a CD or DVD, and store them in the safety deposit box. At the very least, it is almost free to do so, and it can provide a fun look back at your home in several years. Best to do this once a year too, as you can be surprised how much your home and possessions change in a year!
Posted by PH on 01-04-2008 11:39:22 CST

The Paul's Tech MythTV Project: Phase 5

OK, as promised in Phase 4, here are a few customizations you may wish to add to your MythTV box. Most of these are relatively simple, and if you have gotten this far in setting up your MythTV box, there should be nothing here you can't handle.

The first addition I made to my machine was to add a way to check the system temperatures and voltages from within the MythTV GUI. The simplest way to do so, that I have found, is to make a webpage that can be opened in the MythTV web browser. You will need the Mythbrowser add-on in order to use this.

If you recall, in Phase 3, I mentioned installing lm-sensors. Assuming you did that, you can get a listing of the voltages and temperatures with the sensors command. This works great from the command line, but needs help for use in the MythTV GUI. Fortunately, we can use scripting to make it easy. I chose to use php for my version of this webpage, but if you like perl or something else better, it is easy to change. Here is the webpage in its entirety.

Yes, that is all you need. What you have is this: The first line indicates to the webserver that this is a php script. The last line closes the script. The two lines that begin with echo send the pre tags to the browser. This just makes the output prettier. The meat of the code is the system command. This command sends the command in the parentheses to the command line, and captures the output. When run, all of the output you get from the sensors command will be caught and sent to the web browser. Simply save the above text in a .php file (I used temperature.php) in your webserver webpage directory. For me, that is in the /var/www directory.

Now, in the MythTV GUI, go into the Info Center Settings, Web Settings, and create a New Bookmark. Name it whatever works for you (I used CPU Temperature), and for the URL, use http://localhost/temperature.php. Once that's done, you can go into Information Center and Web sections, and if you select the CPU Temperature bookmark, your sensors output should appear as a webpage. Refreshing the page will get you updated output. Handy, eh!

If you are interested in tracking temperature or voltage over a period of hours or days, you could expand on this idea to do so. Let's say you wanted to track it once every day. What I would do is to set up a cron job to run the sensors command. To add regularly scheduled tasks, you will need to edit the crontab file in the /etc directory. Here is an example of what to add.

01 01 * * 00 root sensors 1>/var/www/temperature1.txt

What this says is, run the sensors command at 1:01am every Sunday, the output of which will be redirected to the temperature1.txt file in the webserver directory. You would then add 6 more similar commands for the other days of the week in seperate text files. You can then add new bookmarks for the new text files, and view them in the browser as well. If you are really handy with scripting, you may even want to make a script to read the 7 text files, strip out the pertinent information, and create an attractive webpage with graphs and everything.

The second addition I made had to do with my desire to have the machine automatically download some of my favorite video podcasts to my media directory. If you have MythStream installed, you may be happy with streaming podcasts to your TV, but I wanted them downloaded at night when my internet connection traffic was low or nil. I did this again with a relatively small php script.
Here is the script.

NOTE: I had to make a small change to the above script. The preg_match would fail if the url contained the letters AVI, for example, before the .AVI extension. The above line should now be as follows:

preg_match_all ("/http:+[^\s]+\.+".$fileext."+/", $data, $matches);

The script starts running at the $url=... line. The $url holds the location of the RSS feed of the video podcast in question. This example is for the DL.TV podcast. The extension line below that is the file type we are looking for. With both of those variables set, the script calls the download_videos function.

The download_videos function is where all the magic happens. The first line goes out and gets the RSS feed webpage, dumps it into an array, and then converts the array into one long string. The second line then searches that string for any sections that start with http:, and end with the $ext file type. All of the links found are stored in the $matches array. Those matches are then used in the 3rd and 4th lines to collect the actual mp4 files. The 3rd line calls the command 'wget' with the first matching link. 'Wget' is a program for retrieving files over the internet. The 4th line does the same with the second link found. It seemed that sometimes the first link didn't work, so I added the second one in just in case. If the first one works, the second attempt will not overwrite the first download. Most RSS feeds have the most recent podcast listed first, thus that is the one it will always grab.

The last thing I had to do once I had the script written was to create a cron job to run daily at night to execute the script, much like in the previous cron example. To run it, I just used the line 'php podcastgrabber.php'.

This is a bit of a quick and dirty script to perform the task, but it works well for me. I can check the Videos section of MythTV every day and see what new podcasts have shown up overnight. And, if I find another podcast I wish to download, I simply add 3 more lines to the script with the new RSS feed. Some shows may not have an RSS feed, but they probably have some webpage listing their most recent shows, and that will work in most cases.

So, these are a few customizations I have added to my machine that I find particularly useful. Feel free to use them on yours as well. This is the last major posting on the Paul's Tech MythTV Project, but as new features develop, I will likely be adding new articles now and then. Come back and check often.
Posted by PH on 09-28-2007 16:18:44 CST

The Paul's Tech MythTV Project: Phase 4

Unfortunately, it's been a bit since I did some of the bug fixing for my installation of MythTV. So, I'm going to have to stick to some more general tips and fewer specific ones. Hopefully, you will still find this posting of value.

The default video player for MythTV plays back recordings very well. I had to do very little to help that. The only thing I did was to adjust the screen so that the picture was centered better. This is done under Utilities/Setup, Setup, TV Settings, Playback. Several screens in are settings for Vertical and Horizontal over/underscan percentage and Scan displacement. You can adjust these to shift the picture up/down and left/right.

The default video player is not so good when it comes to playing other types of video files. I download and playback video podcasts on my box, and I needed to setup a different program for that. I am using xine for playback of odd video formats, and it works well for that. To change the player to use xine, go into Utilities/Setup, Setup, Media Settings, Videos Settings, Player Settings. For the default player line, I use:

xine -pfhq --no-splash

That has worked well for me, but your mileage may vary. Also, if you need to install xine or you need some codecs to decode different video files, check out this link here.
Also, for convenience, go into Utilities/Setup, Setup, Media Settings, Videos Settings, General Settings and check the box for Newly scanned files are browseable by default. This will make new videos show up automatically in the Video section for playback. Otherwise, you will have to go into the Video Manager and make them playable.

For me, the default settings for most of the other stuff worked just fine. BUT, in order to get MythWeather working, I had to update my system to the newer version. For more info on doing the update, check out my previous posting.

One of the more difficult pieces to get working correctly is the Optical Disk, Archive function. This is where you go to burn recordings to dvd. There are a lot of steps involved in converting a recording to the proper format for burning to dvd. Any errors along the way will stop you getting a good burn. My opinion on it is to record your shows in a dvd compatible file to begin with, and things will go smoother. I have my recording profile set up to record at 720 by 480 pixels, and 2700 to 4700 bitrate. This gives me a high quality standard definition video that doesn't need re-encoding, and I can fit 3 hours on a dvd. If you need to cram more onto there, try playing with your bitrate settings until you get the amount of video you need.

If you are having problems with your burn, the mytharchive log files will be your good friends. Mine are located under the /var/lib/mytharchive/temp/logs directory. (You did set up the OpenSSH Server so you can easily access these files as I recommended in Phase 3, didn't you?) From the command line, type in nano mythburn.log to easily view the log. Once you find out where it got stuck, if you don't know how to fix it, try searching the forum at for help, or post your questions there.

If you are trying to get your remote control working, be sure to use the irw command at the command line. This will show you what the receiver is catching. Use ctrl-c to quit. If you are getting nothing, then do a google search with streamzap and mythtv and you should get some links with help on installing it.

Well, that covers a lot of little annoying details towards getting it working. I hope you have a fully functional system now. The next Phase is a few customizations that I did that you may wish to implement.

UPDATE: After having spent more time with the system, I found that if the power goes out and the machine doesn't get shut down properly, it can cause some errors in the database. The main one I've noticed is an error in the recordedseek table. This will cause all sorts of odd behavior in the frontend of the box. To fix it, I log into phpMyAdmin remotely, and run the sql command "repair table recordedseek". This seems to do the trick for me. The better solution would be to have the machine on a UPS of course, which I intend to do.

UPDATE: I was having trouble with the screensaver that was installed with my installation. I was trying to watch some Hulu videos through Firefox, and after 10 minutes the screen would fade to black and I would have to wake the system up by moving the cursor. After a lot of trial and error, I finally found a way to shut the screensaver off. I tried many of the things listed on other websites such as setting the dpms to off or using xset to try to shut it off, but none of those seemed to work for me. What I had to do was to go into the file in the /usr/share/mythtv directory and comment out the section where it spawns the gnome screensaver with the # symbol. After saving and rebooting, this stops the screensaver from being started in the first place, and fixed my problem.
Posted by PH on 09-22-2007 17:23:19 CST

How To Change Your Ubuntu MythTV Setup To SchedulesDirect

If you have been following along with the Paul's Tech MythTV project, you are aware that Zap2It Labs is no longer providing updated TV listings directly. I noticed that I had about 6 days of TV listings left in my program guide today, so I decided to make the switch to In order to help you with the changeover, I am posting what I went through so you can replicate it.

I did the following from the command line to update my installation:

sudo sh -c 'echo "deb feisty-proposed restricted main multiverse universe" >> /etc/apt/sources.list'

sudo apt-get update

sudo apt-get install -t feisty-proposed mythtv mythweather mythweb

sudo mythtv-setup

The first line adds the proposed updates repository to your repository list. The ubuntu guys recently added the 0.20.2 update which includes SchedulesDirect support. The next line goes out and gets the updates. The third line installs them. The last line is so you can change your settings from Zap2It to SchedulesDirect.

Before you run mythtv-setup, you will want to get an account with, of course. Once inside it, go to Video Sources, select your source(s) and change your listings grabber to SchedulesDirect, and change your User ID and Password if needed. Hit Retrieve Lineups. Then select the correct Lineup for this video source. When you exit mythtv-setup, it will probably ask you if you want to run mythfilldatabase, which you should. Your account with SchedulesDirect should be set up much like it was with Zap2It.

When I had finished with this, my listings were all there, but some of my other stuff stopped working. Turns out I had to run the update for MythNews, MythGallery, etc. Easy enough to do:

sudo apt-get update

sudo apt-get upgrade

And that should do it. The good news is that my MythWeather is working properly now too.

If you are having different issues, check out the following links and forum threads for more info that might help you.

SchedulesDirect Forum Ubuntu Thread

Ubuntu Forums ScheduleDirect Thread
Posted by PH on 09-11-2007 17:41:07 CST

Quick Tip: Use Your Compact Flourescent Bulbs Properly

Today my oldest CF light bulb died. It was around 3 years old or so. Considering they are generally guaranteed to work for at least 5 years, I found this very strange. When I took it out to replace it, I was reading the writing on the base of the bulb, and there was a warning there. "Do not use in an enclosed recessed fixture". I didn't have it in a recessed fixture, but it was in an enclosed one. My guess is that they can be sensitive to the build up of heat, and the starter circuit eventually dies.

So, it pays to read the packaging carefully before purchasing your bulbs. I notice that some of the newer ones I have don't have that same warning. Time will tell whether or not the manufacturers have overcome that particular problem.
Posted by PH on 09-07-2007 13:35:39 CST

The Paul's Tech MythTV Project: Phase 3

In Phase 2, we went over the hardware build with particular details on the case. Now, I want to talk about the initial software install as it went for me. Depending on your preferences and the way you get your TV signals, your install may go quite differently. Nevertheless, there are some good general rules in this section to help you in getting things up and running.

The very first thing I wanted to do was to check to make sure the hardware was all functioning properly. This includes making sure that all of the drives and RAM are recognized properly, the performance is decent, and the system is staying sufficiently cool. Mythtv runs on top of an install of Linux. I have used Linux many times before, but I am much more comfortable with Windows by comparison. So, I decided to do a quick Windows install first so I could diagnose all of the hardware. I used a copy of XP, but probably whatever you have will work for this. Doing this install confirmed that the dvd drive was bootable and the hard drive was in good working order. Next, I made sure the processor and RAM were being recognized properly, and I installed the network drivers to see if I could get connected to the internet. All of this went off without a hitch for me. I then downloaded and installed a copy of Motherboard Monitor so I could check the processor and case temperatures and the power supply voltages. All checked out within spec. Next I checked to make sure the front and back USB ports were working by plugging a flash drive into them, and I hooked up the speakers and installed the drivers to see if the sound was working. Once I was convinced all of the hardware was good, I destroyed the partition on the drive and started fresh once again.

The next thing is to choose your flavor of Mythtv. Or to be more precise, which version of Mythtv you will be installing on which flavor of Linux. My first attempt to install Mythtv was with Knoppmyth. Knoppmyth is a bootable Mythtv install that runs on the Knoppix linux distribution. It is a reasonably complete install of Mythtv, and you can get it installed and up and running quickly. You may in fact wish to install it once, whether you are planning to stick with it or not, just so you can get familiar with the Mythtv interface and some of the options available.

I can say that the install went smoothly, but I found that I had problems with some of the plugins. At least two of them didn't work, and after some fiddling, I decided that I wasn't comfortable enough with Knoppix to stick with it. So, I decided to blow it away and start over with an install of Ubuntu Linux.

Ubuntu is another distribution of Linux, and it is one that I have used in the past. It is currently my favorite distribution because of the ease of installing and updating it. It is also one of the more complete distributions in that you can get a lot of precompiled software for it.

Now, you can choose from several different install iso's for your particular machine. I decided to stay relatively mainstream, and went with the 32-bit install, even though I could have attempted the 64-bit install. One thing I did differently was to use the Alternative Install disk instead of the standard Desktop disk, on the recommendation of the Ubuntu documentation. You can get that install from here.

Once you've burned the iso file to a CD (I used Nero Burning ROM), you can get on with the install. From here on, I could reinvent the wheel, and tell you what steps I followed, but basically, I followed the Ubuntu install docs. I suggest you follow along with them at the Ubuntu website.

Ubuntu Community Documentation - Mythtv Combined Frontend/Backend Install

Now, somewhere along the way, you may wonder to yourself, "Do I need to do ALL of this stuff?" My answer is "YES, you do." It takes a lot of pieces of software to make a Mythtv box work and work well. Follow the instructions carefully and do all of it if you can. In fact, there are a couple more things I recommend you do, but I will get to those in a second.

One thing they do is install an OpenSSH Server. This essentially allows you to log into the machine from another computer and access the command line. This is a very very useful thing to have as, if you are like me, you will not have a keyboard hooked up to the box most of the time. Once you have it running, if you need a client for Windows to access it, I recommend using PuTTY. You just need to input the IP address of your Mythtv box, and if you are on the local network, you should connect no problem.

They also recommend setting up your guide data. Again, you will need to do it, but there is a caveat on this one. Tribune Media Services is discontinuing free service for Mythtv users, so signing up with them now is not going to work. You will need to get your listing elsewhere. I recommend you look into With the latest version of Mythtv, you should be able to use this new service. Running a Mythtv box without a program guide is not really worth it in my opinion.

One thing they don't mention but that I feel is worthwhile is to install Samba. Samba allows you to share files and printers between a linux box and a windows box. You can find out more about installing Samba here. I set it up to allow me to use Windows Explorer to access my home directory and my media directory on my Mythtv box. This makes transferring videos, music, and pictures around a snap.

One final thing you will want to do is install lm-sensors. This will allow you to monitor the voltages and temperatures of your PC. A good How-To on this is located here. Once you have it working, I will show you a handy way to use it from your Mythtv Frontend in the next installment.

Phewww! That should give you plenty to do. It can take a while to get this all done, so plan to set aside a significant chunk of time. Next time, I will talk about some hitches and difficulties I had to overcome to get everything (or nearly everything) working.
Posted by PH on 09-06-2007 08:35:20 CST

The Paul's Tech MythTV Project: Phase 2

OK! Here we are... ready to start assembling the hardware! First up is the Case.

As I mentioned in Phase 1, I am using an AthenaTech A3701BB HTPC Case purchased from Here are the vital statistics:

  • ATX,Micro-ATX,Flex-ATX Compatible
  • 2 5.25" External Drive Bays
  • 1 3.5" External Drive Bay
  • 1 3.5" Internal Drive Bay
  • 7 Expansion Slots
  • 2 Front USB Ports
  • 2 Front Audio Ports
  • 2 Rear 80mm Cooling Fans (Included)
  • Dimensions: 13.8" x 7" x 15" (W x H x D)
  • Gloss Black Finish
  • Front Power and Reset Buttons
  • Front Power and HDD Activity Lights
  • Bottom Mounted Cooling Fan (Included)

All things considered, I really like the case, and it has worked out very well. However, it does have a few flaws that you should be aware of.

Before you do anything else, you will want to address the airflow issues with this case. The area around the motherboard is very well ventilated, and a well placed cooling fan will keep your processor and PCI cards happy. There is a vent on the top, both sides, and the back where the 2 80mm fans are. I added another fan near the PCI cards to blow air across the video card and toward the cpu. The 2 rear fans exhaust out the back.

The rest of the airflow in the pc is a bit of a mess though. The power supply sits at the front of the box with the plug-in and fan facing the front. As you can see from the pictures below, the spot where the power supply fan should be exhausting air is blocked by the sheet metal of the case. I suspect that is what the bottom fan is for, is to pull air out of that area. It seems totally inadequate to me, so I opted for a different solution. On the side of the front faceplate, there is a little door that opens to allow some air flow. I cut a hole in the sheet metal in front of the power supply fan to allow the air to go forward, and out of the side vent. It seems to be working fine.

The other problem with the airflow is around the drives. There are zero vents in that area. There is also almost no room for a fan in there too. I have the one DVD drive, and one hard drive in that section. I wouldn't worry too much about the DVD drive, as it doesn't see that much use, but the hard drive is another matter. Modern drives can get quite warm, if not outright hot. Since it is such a critical piece, I think some cooling is in order. I recommend you try to find a 5.25" Hard Drive Cooler/Mounting Bracket. I made a piece of my own with a very small 12 volt fan I had lying around. It mounts in front of the 5.25" bay and blows air over the hard drive and DVD drive towards the back of the case. It's far from ideal, but it will have to do.

After you have finished improving the airflow, the next thing I would do is remove the 2 rear fans. The motherboard install goes easier with them out of the way. Take the 2 screws out of the back and slide the fans towards the PCI slots to remove them. Then, I installed the metal back cover plate for the motherboard connectors.

Next I installed the power supply. You will have to take the front face plate off to do that. You can pop the face plate off by gently prying it off with a flat screwdriver. There are no screws holding it on, just plastic clips. I had to plug in the power cord before putting the screws in that hold the supply in place.

The motherboard install is pretty standard. Install the mounting pegs and fasten the board down to them with the included screws. Then, I installed the RAM and the processor. The heatsink for the processor was an AMD standard heatsink. As I had some higher quality thermal compound on hand, I cleaned off the included compound and used my own. Finally, I hooked up all of the wires, such as the power switch, front usb connectors, ATX power, etc. One thing you may want to forego is plugging in the power led light. I found it to be way too bright and harsh.

Next I re-installed the fans, and put in the video card and the video capture card. Finally, I installed the drives and drive cables. You may have to adjust the DVD drive rail placement a few times to get it lined up right with the face plate. Once everything was connected, I used cable ties to make the wiring neater and help the air flow.

One last thing to do before you put the face plate back on is to line up the DVD drive eject button with the face plate button. There is a slider on the plastic rail on the back of the face plate. Align it with drive button, and you should be good to go.

All-in-all, the hardware has worked great. The cpu generally stays in the 40 to 45 degree C range for temperature. It has performed well enough speedwise, and I haven't felt the need to overclock the system, but I am sure it would take the increased temperature easily. The fans are all reasonably quiet, unless the room you are in is very quiet, then you do hear them a little. Obviously, this is something that can be fixed with better fans, if it bothers you. The drive button works ok, though you can't really use it with the tray out, so you have to push the tray back in to close it.

Now that the hardware is ready to go, it is on to the software install. Look for Phase 3 soon!

Posted by PH on 08-25-2007 13:30:00 CST

Why The Frequency Matters

Radio Frequency: Any of the electromagnetic wave frequencies that lie in a range extending from below 3 kilohertz to about 300 gigahertz and that include the frequencies used in radio and television transmission. Merriam-Webster Dictionary.

Recently, a buddy of mine was having trouble with interference on his wireless camera. From the way it looked on the screen, my first thought was that it was a loose or poor connection to the receiver. After fiddling with it, it was obvious that that wasn't the issue. Since it is a pretty simple rig, it had to be a problem with the wireless signal. There were a few walls between the transmitter and the receiver, so it didn't seem inconceivable that the signal was weak by the time it hit the reciever. Only problem was that the glitches on the screen didn't seem to match with a weak signal problem. Finally, it dawned on me. The camera worked at a frequency of 2.4GHz.

I knew he also owned a wireless network router for his home PCs. WiFi, or 802.11, networks also transmit data on the 2.4GHz band. What we were seeing was interference due to the router. That's easy to diagnose, so we just unplugged the router. Funnily enough, that didn't fix it. Convinced that it was radio interference, I tried to think of anything else that would interfere. Turns out, he has a cordless phone too, also working at 2.4GHz. So, we unplugged the phone, and BINGO! No more interference.

The thing I want you to realize, is that there are only a few frequency ranges used in most commercial products. Typically 900MHz, 2.4GHz, and less often, 5.8GHz. You will always see WiFi in the 2.4GHz range, and with a lot of phones using the same frequencies, you can have some problems.

The best way to avoid this problem is to plan ahead if possible. For example, buy cordless phones that work in the 900MHz or 5.8GHz bands. Units in different bands rarely ever interfere with each other.

If you don't have a choice, as in my friend's case, you will need to try setting different channels. WiFi routers can be configured to only work on certain channels numbered 1 through 11 (in the US). Your best hope is to try changing the channel on the router and see if that clears up the interference on the other device. If not, you will need to change the channel on the other device, if it has the option. It can take a bit of screwing around, but with luck, you will get it.
Posted by PH on 08-18-2007 17:51:39 CST

The Paul's Tech MythTV Project: Phase 1

Here we are! The first steps into building and installing an open-source DRM-free media center. I thought it would be a good start to give a little background. I've been using a Tivo with a DirecTV satellite receiver for several years now. Before that I had been using a VCR to store TV shows and movies for later viewing, as many people did. But, I really got sick of the low quality of most video tapes at one point, and I purchased a 1st-gen Tivo second hand. While limited in storage space, it was WAY better than using a VCR in so many ways. Using a hard drive for storage meant no more missed shows due to bad tapes, and the Tivo program guide meant automatic recording of the shows I liked. To this day, I am still using that same Tivo (after having upgraded to a larger hard drive and purchasing the lifetime subscription), and it has functioned flawlessly. There is no doubt in my mind that Tivo has the best user interface of any DVR I have seen. In fact, if not for certain needs and new opportunities, I would keep on using it. (Note: The MythTV/HTPC project is definitely a major undertaking to build. You WILL have to do some fiddling around to get everything working, and you may have to do the occasional twiddling to keep it working. If you are unable or unwilling to spend the time, and I wouldn't blame you, you should at least check out a DVR for your cable or satellite service. You won't regret it.)

How my needs have changed is due in part to how TV is changing. With the future going to High Definition TV (HDTV), this was bound to be a problem for my old Tivo. It doesn't have the ability to store an HDTV recording without a major drop in video quality. This is assuming I could even find an HDTV tuner that would work with it. Also, one problem with the Tivo is getting the video off of it for longer term storage. In the past I have copied things to tape if I wanted to keep them for a while. But, it is inconvenient, and we all know that tapes are going away more and more all the time. At a minimum, I would like to be able to store things to DVD quickly and easily. Lastly, I would ultimately like to be able to store ALL of my video on one device so I could have access to any movie or TV show at the click of a button. This was unrealistic until the past couple of years or so when hard drives reached a sufficient size to hold that much data. These are the main reasons for me, but the box is capable of many more things, some of which may be important you.

OK. So perhaps you are intrigued. What is it then? Well, the simplest answer is that it is a digital video recorder that can pause, rewind, and fast-forward live TV, as well as schedule and automatically record TV shows for later viewing. Long story short, you control when you want to watch a TV show. But, a MythTV box has many more features. Here are some that are implemented at the time of this writing.

  • Edit and store recorded videos to DVD.
  • Browse the web.
  • Copy, store, and play back DVDs on the MythTV box.
  • Store and view pictures.
  • Play video games.
  • Store and play music.
  • View and edit your Netflix queue.
  • View RSS News feeds.
  • Get weather updates.

These are some of the features, and more will be built in time, but you can already see the power of the system. It truly is a way to store and manage all of your media and put it at your fingertips.

This was enough to tempt me to give it a try, so I started by getting some PC components together. I am going to assume you have some knowledge already regarding PC hardware, as there is a lot to get through. As you get more into the MythTV scene, you will see postings from many people saying how they have used it with older systems like pentium IIIs and such. They may be basically functional, but let's face it folks. Video is one of the few things that will really stress a computer, and it will eat as much processing power as you can throw at it. So, I recommend getting as much horsepower behind it as you can within your cash budget and your temperature budget. I'll talk about what I mean by temperature budget a bit further along. Let's take a look at the pieces I purchased for my rig.

  • AMD Athlon 64 X2 3600+ 2.0GHz CPU with Heatsink and Fan
  • Kingston 512MB DDR2-800 RAM
  • Asus M2N-X AM2 NForce520 Motherboard
  • Sony 7170A-0B Black 12X DVD Burner
  • MSI MX7300LE 128MB Video Card
  • Hauppauge WINTV-PVR-150 Non-FM TV Tuner Card
  • AthenaTech A3701BB HTPC Case (w/o Power Supply)
  • StreamZap PC Remote Control

Now, close observers will notice that I have left out a couple of key items. I already had an old 40GB Western Digital hard drive, and I am using it for setup and testing for now. Once I am fully comfortable with the system, I plan on purchasing a ~500GB SATA drive. Also, I already had a Seasonic S12 380W very quiet power supply from a different PC that didn't need it anymore.

The processor was chosen for both the low price and decent power. As a plus, it is dual core which offers some future dual video processing capabilities (I.E. running two simultaneous transcoding jobs), and it is overclockable should more GHz be required. Related to the temperature budget I mentioned before, I want this PC to be as quiet as possible so it is not whirring loudly while I am watching a show. This means getting passive cooling devices and low wattage parts as much as possible. This CPU is a 65W part, and with the stock cooling, it runs quite cool and silently. If need be, a large passive cooling device from Zalman is an option.

The DDR2-800 RAM was also to aid overclocking. According to the MythTV websites, there is little to be gained by installing more than 512MB of RAM, but in hindsight, I would have sprung for the 1GB to give a bit more headroom.

The motherboard was chosen for it's features amenable to a Home Theatre PC (HTPC). It has both IDE and SATA drive connections. It has 3 PCI slots and 1 PCIE-x16 slot. It has onboard audio, and does NOT have onboard video. And, it has several USB ports, a com port, and an ethernet port. The hard part was finding the 3 PCI slots, as they seem to be fading away. If you want to install multiple tuners, or run multiple TVs off of the unit, you need lots of slots. The rest of the hardware you will find out the why during the hardware install later.

The next step is to start the build! I'll try to get something up on that soon, so stay tuned!
Posted by PH on 08-06-2007 10:24:53 CST
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