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2009-02-10

Feinstein Wants To Burden ISPs With DRM

The esteemed Senator Feinstein of California has been hornswoggled into cramming an incredible burden to ISPs into the latest economic recovery package. Click on the link to read about this incredible waste of resources, and for a connection to call key senators to tell them, No Way.

2009-02-09

Is Sustainable Power Unsustainable?

Looks like the high-efficiency solar cells which forecasters have planned on require rare metals we'll run out of in about ten years. And, the best substitute expected, carbon nanofiber, is shown by two independent studies to pose a health risk similar to asbestos, as per a linked Seattle P-I story. Eek.

This only emphasizes the need for more basic research, not less, in energy generation of all kinds, such as these nuke-sized solar power fields (Link 1, Link2) which California's PG&E is studying. These sunpower fields use an array of tracking solar dishes powering Stirling engines which work with any concentrated heat source.



Gee, doesn't Oregon get a lot of constant sunshine east of the Cascades? Hmm... the 'golden triangle' of lower Malheur and Harney counties (see map, above, with marker at Baker City), including the hamlet of Fields, with its apex near Alvold Lake, gets at least 4.5 kilowatt-hours per square meter per hour, even in January, which is the 'worst-case month. Other months of the year, it gets more... and that's pretty darned close to the Big Island of Hawaii according to this DOE Map. When it's sunny, the wind blows less, so Stirling-engine-solar there these would be a good partner to Oregon's windmills, because when there's no wind and windmills don't turn, we now use carbon-emitting inefficient gas turbines to substitute for the wind turbines, because you can't quickly fire up a coal plant like Boardman or a nuke like Hanford's WPPSS #2.

Clean energy jobs for Oregon. Anyone interested?

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DTV: Do You Want the Good News First?

The local rep for the LCCR for DTV issues passed on the news today that all Portland stations are postponing their transition from full-power analog to full-power digital until June. That's the good news, sort of, and is a full one-eighty-degree reversal from last week's news, confirming what an O-blogger said earlier today.

Less good news? Well,
  • This will cost some TV stations more, for those TV stations who leased a temporary DTV transmitter, as they have to lease the temporary gear longer. TV stations are already hurtin' because advertising's down; this will hurt more.
  • All stations will be paying more for power in the four months until the delayed cutover date, as DTV is more power-efficient.
  • The companies who bought rights to the spectrum which cutover would release will probably demand a rebate from the feds, and the feds will probably give it to them;
  • Their new services, which would deliver more digital services to sell, won't be generating revenue while Portland TV is still analog. And,
  • Public safety radio operators who need the rest of that freed-up spectrum must delay their plans to increase police, fire and public safety radio system reliability.

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2009-02-07

Giant Blackberry Carved From Ice

Comment number two is worth a chuckle. Enjoy.

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2009-02-06

Must... Buy...

the Star Trek Communicator VOIP/Skype handset.

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2009-02-02

Directions of TV Stations from where you are



TVFool.Com provides you with a way to aim your UHF antenna, an estimate of how much antenna you probably will need to get good reception (see this example) based on your address and height, and how many stations you will be able to receive with that new antenna with DTV.

News you can use, right?

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DTV Springs Ahead, Congressional Delay or No

There will be no ABC, CBS, Fox, NBC, or PBS transmitted in analog signal in Portland/Vancouver, as of noon on Tuesday, 17 February. None.


The Washington Post reports the Congress is still divided on postponing television's conversion to digital; but that is not important to Portlanders, for all major network stations are going ahead with the digital conversion in 15 days. 


All those stations already have digital transmitters up on the air. See these earlier blog posts for the frequencies:
tinyURL.com/dtv-pdx List of old vs. new Portland area channels and flowchart showing what to do.
tinyURL.com/dtv-qanda Q&A on DTV conversion.
tinyURL.com/dtv-ready How to tell if your TV set is digital-ready.



A TV station engineer and volunteer radio operator (the two often go side by side) in Eugene has written this technical discourse of why a better antenna's needed. Our gracious thanks to Carl Sundberg of KMTR who has allowed the reuse of his wisdom and experience to provide a learned explanation of why better antennas are better:


Understanding Digital Television Reception Problems

Carl Sundberg – KMTR TV Engineer


Without question, it’s easier to receive the old analog TV channels than the new DTV channels. The reason is very easy to understand. If you are listening to drum beat where there is a very loud echo, you can count the beats easily as long as the beat is very slow. As the drum beats speed up, it gets harder and harder to tell if you are hearing the primary beat or the echo and at some point, that echo makes it impossible to be able to count the actual beats.


Analog TV had one primary signal that locked up the entire receiver. That signal pulsed at 60 times a second. The new digital signal has 8 beats that pulse at a total rate of over 19 million times a second. Because television signals can’t be heard by our ears, we don’t realize that television signals can have echoes just like sound. With an old television signal, we could see those echoes. They appeared as a secondary image that made the picture look like there were ghosts in the background of all images. Because the main signal that caused the receiver to work was at a rate of only 60 times a second, most TV receivers could lock up to that slow rate signal even when there was an echo present. Like you, listening to a slowly beating drum, the receiver could readily properly figure out what was the main beat it needed to use.


Since TV signals can literally bounce off of everything, signal echoes are every where. You can not eliminate them completely. Like a person listening to a drum beat where echoes can be heard, you can reduce the number of echoes by making your ears more directional by cupping the palm of your hand over your ear. If you use a funnel to listen through, you can really make your hearing very directional. We utilize this concept to make microphones more directional. Microphones used to record orchestras are usually very long tubes with the pick up element in the end of the tube.

Since your new digital TV or converter box is trying to receive multiple pulses that are cycling at an extremely fast rate, it gets very important for your antenna to be like the orchestra tube microphone. It needs to be pointed at the strongest signal and it needs to eliminate as much echo as possible. The traditional rabbit ear and loop antenna is a little more like a human ear. They pick up signals that come from all directions. If you use one of these devices with an amplifier, you not only amplify the signal, but the echoes as well. So, amplified antennas of this design can actually make it harder for your digital TV to work in cities where there are strong signals.

Below are some pictures of set top antennas that are more directional than rabbit ear type antennas. Both of these antenna types not only pick up the signals better in one direction, they also block some of the echoes that are coming from behind it.


Both of the two antennas shown above are designed to work with UHF channels 14 through 65. When the digital channels everyone is using switch to some VHF (channel 2 through 13) and some UHF, these channels will require a different type of antenna. The antenna on the right has traditional dipoles (rabbit ears) folded into the case. Directional antennas will be important for the VHF channels, but they suffer less from echoes than the higher UHF channels because their wave length is longer and it takes bigger objects for their signals to bounce and make an echo.

Signals can be blocked by anything. Some objects block signals better than others. Metal objects and hills block signals very well, but you can even see a change in signal when a person walks by an antenna. For this reason, to get the best and most steady signal, an outside antenna, at least 15 feet from the ground is the best kind of antenna. By being at least 15 feet above the ground, you will be reducing echoes that come from passing cars and trucks. Another reason outside antenna’s work best is because they have more room to be larger. To make an antenna very directional, the pick up elements need proper spacing. This spacing takes length. The antennas above have many elements, but it would be even more directional if they were longer for better element spacing.

Don’t be surprised if an outside antenna works best when you point it in a direction away from a station. Many antenna installers will tell you they have pointed antennas at metal roof tops or water towers to get the best signal. If you have a hill in the way, sometimes you can find a metal roof top on a hilltop house that will make a good signal reflector for that hard to find, clean, echo free signal. Below is a picture that shows how multiple signals can cause a receiver to have pick-up problems.


Good luck with this new technology. And always remember, echoes are what cause a signal to be difficult to receive. Very directional antennas work the best.

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Comcast Strengthens Lock-In: Free WiFi for Commuters

Comcast is ever-vigilant in its search for ways to ensure, once you sign up, you never leave... this 'Hotel California' strategy now gives free WiFi for rail commuters in the NY/NJ/CT area, where a two-hour commute is not unheard-of. 

Every dot on the map at left shows their coverage. They start at stations, and then expand along that route. 

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