Rate your DTV converter

I have the Zenith.

I also live in the fringe area and I am in the process of erecting an antenna tower.

I bought the big bertha of antennas and a good rotor.

With my old setup my reception was marginal but when I added the converter box it was worse. When I studied the signal propagation I realized that it was a problem with my antenna, hence the change.

Check out

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This web site will allow you to predict reception in your area.

Also if your neighbor has a tower and a rotor you might be able to bring your box to their TV and give it a test.

Good luck.

Reply to
Roger Shoaf
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According to the research I've done, other than "low power" stations (and I still haven't found a satisfactory definition for what makes a station "low power" - I imagine if I were interested enough to root through the FCC legalese and tech stuff, I could find it, but I'm not motivated enough to bother) after the switch, broadcast TV is going to exist only on the frequencies that now correspond to UHF channels 14 through 51. Which means that for "proper" reception, the range the antenna needs to be useful on is 470-698MHz. Expecting any kind of decent performance at all out of a ham antenna tuned for 145MHz on TV frequencies is... Well, putting it as kindly as possible, just short of utterly insane. Quite literally, you'd get better performance by cutting off a chunk of co-ax cable and stripping a bit more than 4 inches (VERY approximate number - Exact length can be calculated from online information) of the braid off one end to make a quarter-wave "wick" antenna before plugging the other end into your TV/converter box.

Since you'd be working on standard UHF frequencies, a standard UHF amp should work just fine, but make sure you locate it as close as possible, electrically, to the antenna's feedpoint to minimize the inevitable RF "crunge" the rest of your feedline is going to add to the mix. You want to amplify signal, not noise, doncha know :)

Reply to
Don Bruder

Sorry, Rob, but that's *TOTALLY* incorrect. One of the primary purposes of the switch is to open up the VHF bands for other uses. *ALL* digital transmissions are on UHF now (on channels 14 through 51, between 470 and

698MHz, to be exact) and will remain there after the switch. This includes the digital signals from stations that are currently transmitting analog on VHF channels. What will change is that the analog signals (whether they're currently on VHF or UHF) of all stations will be switched off, leaving only the digital signals that are on UHF frequencies. The only other "change" will affect some stations that are currently transmitting digital at less-than-full-power - They'll bump their output up to their full licensed power once the switch is completed.

The only exceptions will be what are termed "low power" stations (I haven't bothered to find out exactly what it is that makes a station "low power", although the information is certainly out there if someone cares enough to look for it) which will remain where they are, transmitting in analog mode as they always have.

Reply to
Don Bruder

Correct so far.

Partly correct, but for exactly the opposite reason you think. VHF antennas will indeed become essentially useless. However, this is because *ALL* digital transmitters are already on UHF (though some are operating at lower-than-licensed power levels) and will stay there. When the VHF signal is turned off in February, the VHF antennas will still function as (lousy) antennas, but performance is likely to be so poor that they won't be useful except in cases where there are very strong signals.

And no, it doesn't matter that a station is now on a VHF channel, yet transmitting digital - What's happening is that they're transmitting on two separate frequencies - The standard analog signal on their "old" VHF frequency, the digital signal on their "new" digital frequency. Which, in *ALL* cases, is in the UHF band.

Reply to
Don Bruder

On 1/7/2009 10:20 PM Don Bruder spake thus:

That's what I gathered also. So what are they going to use those old VHF channels for, do you know?

I find it interesting that nobody seems to be commenting on one important aspect of this whole deal, which is that we, the people (you remember that phrase, right?), who own these bands as (formerly) public communications pathways, are being given a take-it-or-leave-it proposition where they might (or probably will) end up in private hands. This would have caused outrage maybe 20-30 years ago, and someone may have even demanded an FCC investigation, but at this point, all we can do is throw our hands in the air, roll over and play dead.

Reply to
David Nebenzahl

It's my understanding they will be used for wireless networking. One problem with 802.11 at 2.4GHz (which I currently use over longish distances [2-7 miles] here in rural Oregon) is that the signal won't go thru trees. VHF doesn't have that problem. VHF will also go thru most building walls.

The licenses for those VHF freqs should be transferred from TV to Internet Service Providers, especially in rural areas. It's almost always in private hands. Except for military, the US Govt doesn't do all that much broadcasting compared to civilian uses. Private hands? You mean like Amateur, or CB, or GPRS?

Reply to
Roland Latour

On 1/7/2009 10:58 PM Roland Latour spake thus:

You misunderstand; I mean the current "airways" (VHF band in this case) are public in the sense that they're public property (i.e., not privately-owned, administered by the FCC) and also subject to public oversight (well, at least nominally). You know, like that little thing called the First Amendment?

Reply to
David Nebenzahl

So, in reality, I could saw off the LARGE end of my VHF-UHF antenna and just use the end with the small beams..... Right? (Not that I intend to do this, just asking).

Or to put it another way, I could buy a UHF (only) antenna, and would have a much smaller antenna on the roof. Right?

I could see having a smaller antenna as a benefit, because I could make my mast a few feet higher without having so much worry about high winds ripping it down. Of course I am not sure if another 6 or 8 feet of mast would make much difference.

Reply to
Jimw

Not true in all markets. In fact, in the Wilkes-Barre/Scranton area, two stations are moving out of the UHF band down to channels 11 and 13! Previously, all stations were UHF here except for the low power catholic station on channel 7. I made a simple dipole cut for channel 12 and it works fine to pick up 11 and 13 digital signals.

Reply to
BR

no no no, nearly ALL remain UHF, since the new users of TV band prefer VHF. the lower frequencies go thru buildings etc better

Reply to
hallerb

This entire conversion is a basic rip off of the public!

If the digital channels worked as good or better than the analog for nearly everyone then fine go ahead.

the trouble is the digital channels in far too many cases dont work as well.

call your congressmen and COMPLAIN BEFORE THE SHUT OFF!

Reply to
hallerb

You may want to check your references. The "new users" will be operating in what is now part of the UHF TV band.

While you are doing that you will also find that Clinton was a big proponent of DTV and signed the legislation into law.

Reply to
George

I have a Magnavox converter and get excellent digital reception. In fact I get NBC and FOX which I never got on analog. A friend who lives about 15 miles away gets only one station with digital even though he has good analog reception of 5 stations. He has a good outside antenna and uses RG6 cable. He is not happy.

---MIKE---

Reply to
---MIKE---

There is a station that holds and uses a DT license on VHF in my home market and I can think of at least 3 more markets that have DT operating on VHF.

When

Reply to
George

The space between channels 6 and 7 are being used for FM broadcasting (88 to 108 mc). These will not change and a VHF antenna would still be needed for these stations.

---MIKE---

Reply to
---MIKE---

From several reviews there seems to be 4 catagories from poor to very good covering several areas, do you believe they are equal or the present reviews wrong in what you will get. From my take on it online is where the better box is, and price is a reason, it is a fact WalMart demands low prices from supliers.

Reply to
ransley

In theory, yes. In practice, probably not. In most cases, those combination antennas have been carefully tuned so that they perform well across all the bands they pick up. Altering them in any way *WILL* alter their capabilities. Every piece of metal within (depending on which reference you want to believe) 1-4 wavelengths of any element has to be accounted for in the tuning process. Depending on the exact design being used (the "Yagi" is probably the most familiar), changing number of pieces, size of any piece, or spatial relationship between any two pieces even slightly can have anything from very little effect to an "I can't freakin' believe it!" huge effect on the antenna's performance. Lop a chunk off any of them, and it's pretty likely that they'll go almost completely "out of tune" for whatever part you try to keep in service. It wouldn't be impossible to retune an antenna once the VHF section is chopped off, but chances are high that it would take so much time/effort/tinkering to do it that it simply wouldn't be worth bothering to make the attempt.

Yep.

In theory (once again...) raising an antenna any amount is helpful. But in practice, there's a "minimum increase" number (Which I can't remember for certain without looking it up - I'm wanting to say it's 10-12 feet) below which the change doesn't give any significant payoff for the effort.

Reply to
Don Bruder

Sorry Don. I'm afraid you are very confused. The frequencies associated UHF Channels 52 to 69 are being auctioned off - not the VHF frequencies. Stations have the option of moving their digital channels back to VHF after the transition if they want, or they can stay on their temporariy UHF channel if it is below 52. Since low VHF has better propagation than VHF and is cheaper to run a transmitter on, those stations current on 2-7 for analog will likely stay there for digital.

Reply to
Robert Neville

There's been talk about that, but the main "target" was supposed to be "public safety" - AKA fire, cops, ambulance, etc.

The wireless networking concept is/was aimed at so-called "white spaces" between current TV channels - sort of "slipping it into the gaps"

VHF has its own set of problems for use in wireless networking. Yes, it'll give better "penetration", and all other things being equal, longer distances. But when you drop in frequency, you also drop in information-carrying capability - Current wireless, running in the 2.4 GHz range, has *LOTS* of "cargo space" available, so top speeds possible with it are much higher than what can be had from a signal in the VHF bands (which are *WAY* down the scale: 54-88MHz for "VHF-Lo" - channels

2-6, and 175-216MHz for "VHF-Hi" - channels 7-13) Lower frequency = lower information carrying capability. The most clearly visible illustration of this would be comparing the AM and FM broadcast radio bands - look at how cheesy an AM station sounds compared to an FM station. PART of the difference is the modulation scheme, (Amplitude Modulation versus Frequency Modulation) but a much larger part of the difference comes from the amount of information each band can carry - AM broadcasting is done on frequencies between about 500 and 1600 *KILO*Hertz, while FM broadcasts are done on 80-ish to 108-ish *MEGA*Hertz. Higher frequency permits more information per unit of time to be moved. But it trades off distance the information can travel intact - Some of the so-called "clear channel" AM stations can literally cover the country from coast to coast with good strong intelligible signal, using only 50 *KILO*watts. An FM station running a full *MEGA*watt is hard-pressed to get a useful signal out past about 100-150 miles.

Shifting wireless down to the VHF bands will give slower, but further-reaching, wireless connections. For some folks, "some but slow" is one helluva lot better than "fast but nothing", but in general, most of the general public is stuck in a "gotta be faster Faster FASTER!!!!!!! to be any good" mindset, so I'm wondering if that idea is

*REALLY* going to get any traction...
Reply to
Don Bruder

And if you are interested, this is a reasonable explanation of what is happening:

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Reply to
Robert Neville

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