A new WHAT?!

PLAYONLINUX UPDATE: OK…well, I had a prior post concerning “PlayOnLinux” that didn’t go too well. A few more of the programs that I tried, did start the installation process, however they didn’t work too well. I knew that I should have checked them on winehq.com I keep forgetting that WINE is the process translating the programs, not this new one. lol

Well…the triplebooting of Ubuntu, Vista and W7 is working pretty good. I’ve noticed that 7 is using the same registry keys as Vista, or something else is going on. I’ve got programs installed under Vista, and when I play them (browsing to the correct location and executing them) they run just fine. Faster, in fact, than in Vista. How is this possible? Supposedly, reviewers of the new OS say that they streamlines the statup/shutdown procedure, but the core is built from Vista (hence the version 6.5) But then again, my Vista has had programs installed and removed many times. Oh well. The programs start and stop faster, but they run just as they did in Vista.

One thing that some folks may not understand….
Even though 7 is a new OS, and many folks still have a bad tast in the mouth from all the initial Vista problems, it is still built from Vista. If your PC runs like crap with Vista now, it may still run like crap on 7. The drivers are the same, therefore the hardware issues are the same. They made have made minor code changes to let it be more forgiving of hardware, but if you refuse to upgrade your hardware, you’ll still have problems with 7.

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antenna-rooftop

/rant <on>

OK…so I’m in a retail store the other day, and I hear a customer asking for a new “digital antenna”. Wow…can people not understand the way TV works? Wow… The person came in a few days prior to buy a converter box because of the transition (which is today by the way). No big deal. plenty of folks have bought one. Anyway, they are asking for a digital antenna because their smart-ass geeky teenage neighbor told them it was needed, so here they are. The employee explained to them that it is not necessary as their existing antenna will work (they have an external roof type). They then went on how their neighbor was smarter than the employee and they wanted a “digital antenna”. I had to intercede.

Out of the blue, I gently asked the customer if he needed help (yes, I work there too.) He asked, I answered:

“Sir, there is no special digital antenna that is used for the new broadcasts. What we do have, is an antenna amplifier that will strengthen the broadcast signal that your existing antenna is already picking up, and allow the converter box’s receiver to properly decode the signal.”

He then goes into asking my how I got my information. Well…I am a HAM radio operator, I worked with digital and analog electronics for the military for 11 years, and electronics is one of my hobbies. He pretty much shut up at that point, and then decided to learn more about the technology, which I was GLAD to tell.

/rant <off>

The thing that most folks of his…(demographic, era, age, whatever) seem to misunderstand, is that the frequency of the new broadcasts is damn-near identical to the old ones. However, instead of having 1 frequency per channel, they can put two or 3…all digitally transposed on top of one another and easy for the box to separate.  This changes nothing in respect to the antenna…

The antenna shouldn’t be thought of as a separate device, but rather as an extension of the receiver. The receiver is what receives the signals, IT is what decodes the signals, not the antenna. All the antenna does is pass the signals TO the receiver.

Yes, the antenna is important; without one the receiver won’t have anything to decode, but the only thing about the antenna that is important is the tuning of which signals it will pass.

***WARNING!!! ELECTRICAL THEORY AHEAD!!!***

A basic antenna is a wire. The length of that wire is the key. A long wire will receive low frequencies, a small wire, high ones. FM radio: the frequency in the middle of the band is 98MHz…and the wavelength is just over 10 feet. AM radio has an average frequency of a much lower 1117kHz and a wavelength of 880 feet!! MUCH longer! An antenna of those sizes will pass those frequencies through to the receiver with very little loss. Obviously we don’t have 10 foot antennas on our cars, instead we have one that is 2.5 feet…1/4 of the wavelength. Multiples of 2 usually work well for frequencies. 1/2, 1/4, 1/8, etc. They become less effective as you go shorter, but they work better than nothing at all. If the size is not on one of these multiples, it doesn’t get rejected, just attenuated and lost as wasted energy. You can have multiple sizes on one antenna too…like the ones on a roof antenna. That allows multiple frequencies to be tuned, but it also does a special thing…it amplifies signals coming from one direction! Well…not really, but it does pay much more attention to the signals coming from one direction…a passive amplification. That means that the receiver can have more signal to decode. But what signals get passed along? All of them.

Every signal in the world. Digital, analog, Wifi, Bluetooth, space transmissions, aviation conversation, cellular phones… every frequency, every modulation of signal. EVERYTHING! Any device that has transmitted a signal. That signal goes through space/air and is picked up by the antenna. The AM frequency from a state away. The FM signal from the city TV station. Your neighbor’s Wifi. Your cell phone. They are all being picked up by your TV antenna.  If they happen to be near or on one of the tuned frequencies, they aren’t attenuated and your receiver receives them.

Then IT…the receiver…filters out the ones it doesn’t want and decodes the signal. If it is an AM signal, it processes it as AM. FM, FM. Digital? It sends the signal to a processor to be decoded, translated, then sends that information to your TV or radio. BAM…now your watching 24, or Lost.

So what happens if your neighbors Wifi breaks and starts transmitting on your TV frequency? Are you going to start seeing his net traffic on your TV?  HA HA no. The converter box will only decode the special signal that it was designed to receive. Wifi uses a different protocol of ones and zeros to transmit it’s data, and your converter box isn’t designed to process those.

However if the new, unwanted signal is stronger than the one you want, you’ll lose your picture, or music. This used to be a problem with AM radio, and still is on AM radio and CB radio. Amplitude Modulation.

Ever notice the HUM of an AM radio station? That’s the sound of the 60Hz AC power running along the power lines…bleeding onto the surrounding frequencies. Yes, its a long way from 60kHz to 1MHz, but if the power is unclean, as it usually was back in those days, the power wires act like a giant antenna, sending that 60Hz signal onto all kinds of frequencies. The style of modulation, amplitude modulation, takes the information and amplifies the signal stronger and weaker to change the power of the signal, based on what is being input. A person talking, music…it all modulates the power of the carrier frequency (the tuned frequency of the radio), and you get your NPR. If something creates a noise, or any signal at all on that frequency, your hear it. A tick, static from lightning, etc.

FM, or frequency modulation, doesn’t change the strength, but the frequency instead. It changes the carrier wave by increasing its frequency very slightly up and down. The louder the music or speech, the more the frequency changes…but the power doesn’t. This feature of FM pretty much got rid of any lightning static and the AC hum from power lines, and even today is a fairly strong way of transmitting information. You can still hear a slight lightning tick if a bolt strikes near because the lightning signal is so powerful, but it takes a LOT to lose the signal or bleed over it. The only time I’ve heard bad static or interference is when you have 2 FM radio stations very close together on the radio. You have to be at the right spot where you’re losing one, and getting the new one. Even at the end of the transmitted range, you might get static because the receiver is receiving a signal so weak that it has a hard time decoding it, but you can still hear or see the signal.

Digital is something brand new and something that has a lot of room to grow. Instead of changing the carrier’s strength or frequency, it transmits in a modulation called PM…pulse modulation. This is an on and off switching of the power (similar to AM), but it’s in a digital format. More of an instant on and instant off, in a special sequence that only a converter box or digital-tuner TV can receive. If lightning strikes right outside your house it won’t change the picture (if it doesnt cause power to go out, or blow up the TV). The converter box sees the new signal and ignores it because it doesn’t fit the sequence of data. Done. Nice touch eh? Plus, since it is a digital format, you get the picture as it is meant to be seen…exactly as it is transmitted. The only problem, as many folks are finding our now, is that it’s all or nothing. There is no static to see through because the data can’t be decoded…like a dropped cell phone call, or the cutting in and out of a cell conversation when you’re in the dead-zone with no bars. All or nothing. That’s why the amplifiers are so popular, and why most of the new antennas have one built in.

Your existing antenna will work fine because it ALSO receives the new signals and passes them on to your new TV or converter box. You just might need to buy a DTV amplifier. That’s all.

OK…Sorry about the theory, but it was necessary for me to vent, and if you learned something, cool! If you do wish to read more, feel free to search the web on AM, FM and PM modulations. If you can leave a comment and I’ll fill in.

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