THE HD INBOX: JULY 2009

Can You See It, Or Not?

Q. Since all TV programming is heavily compressed, whether OTA, cable, or satellite, there shouldn't be any advantage buying a 1080i flat panel vs. a 720p flat panel. In other words, you won't see any resolution improvement watching a 1080i TV. Is that a fair statement to make? Of course, if you plan to use a Blue-Ray player then, yes, a 1080i or 1080p panel is the correct choice.

A. Well, it’s not quite that cut-and-dry. While it’s true that HD programming is compressed quite a bit by the time it reaches your TV, the quality of the HD signal will be evident on an HDTV set that has decent video processing. By that, I mean that a 1080i HD sportscast on CBS — which does not multicast — will have more detail on a 1080p-resolution TV than on a 720p model.

On the other hand, if a station is multicasting a 1080i channel and one or more SD channels, then there may be no advantage to a 1080p HDTV, as you’ll just spot the compression artifacts much more readily. A third argument — if you watch mostly ESPN and some sports on FOX and ABC, then you’re watching the 720p format exclusively, so a 720p set will fit the bill nicely. (The MyHD network also uses the 720p format for several of its stations.)

Of course, all of this is becoming a moot point as prices on 1080p HDTVs continue to drop. I’ve seen 50-inch 1080p Panasonic plasma sets with 1080p resolution for just under $1,000 now. 42-inch 1080p LCD TVs are well under a grand, while 46 and 47-inch sets are now inching below the $1K mark, thanks to aggressive pricing by companies like Vizio. And that means fewer 720p models are coming to market. So, you may not have a choice in the near future!

Polarization Clarification

Q. In your review of the RCA ANT1500, you state “VHF TV broadcast antennas are designed for circular signal polarization, similar to what’s used on direct broadcast satellites, while UHF TV antennas are usually set up for horizontal polarization.” This isn’t usually true, at least not yet. As Doug Lung states in his article “Circular Elliptical Polarization for TV” in TV Technology http://www.tvtechnology.com/article/67946,

“Most stations today transmit signals using horizontal polarization only. Of the 1,237 licensed DTV stations listed in my CDBS TV Engineering spreadsheet for Aug. 27, 2008, only 6.2 percent use any vertical polarization, while 13.7 percent of the 699 post-transition construction permits have at least some power vertically polarized. As FCC interference and allocation studies are based on horizontal polarization only, it is relatively easy to modify an existing construction permit to specify elliptical or circular polarization, so we may see this percentage increase as more broadcasters examine how their over-the-air signals will be used.”

It’s a good review, and the results were as I expected. It’s one more antenna I can tell people to avoid who wish to receive our VHF DTV station (KAET-TV in Phoenix, AZ). Actually, as Doug Lung states in a different article http://www.radioworld.com/article/68820 , circular polarization would probably help reception on UHF-only antennas, so many of which are called “HDTV antennas”. Since our switch from UHF 29 to VHF 8, we have been flooded with calls from people who can’t receive us anymore with any of the new “high-tech” looking antennas, even those that claim VHF reception. Your suggestion that it only be used within 10 miles of a VHF station with line of sight is what I’ve found in practice with UHF-only antennas, too. I personally live 10 miles from our transmitter and I use a cheap DB2-style antenna (Eagle Aspen DTV2BUHF) on my roof and get a good VHF signal with no dropouts.

A. Thanks for the update! The ANT1500 may look good on your TV, but it has no gain at VHF frequencies and any success that readers have had with it is likely due to close proximity to the DTV station being received — the signal is just so strong that it’s coupling into the receiver via the ‘brute force’ method.

Not Like The Good Old Days

Q. We live in Warminster PA, and never had problems with analog reception using a simple indoor antenna from RCA: Model # ANT 145. It came in just great. I went to (the) HDTV antenna website (antennaweb.org) & typed in (my) address. The information was this antenna was fine for digital TV, especially being about 13 miles from (the) source.

We bought am HDTV (Toshiba) last November, & (with) every little breeze of wind, the signal goes out. The digital boxes I purchased for two other TV's don't do it as much, but also at times are bad from wind blowing. I know (the) antenna is the problem, but what (indoor) antenna(s) should we get for this situation?

We have waited for the digital change, hoping the signal power gets stronger, but feel that this may not improve our problem. Please note that we can't afford anything but free TV at this time, and my 89-year-old mom is taking it out on me about this signal loss, when a little wind blows. Your advice would be greatly appreciated.

A. If I had to take a guess, I’d say that your digital TV signal levels are marginal at your home to begin with, and normal signal fading due to winds blowing trees around — not to mention the TV transmitting towers themselves — is causing the DTV signal to drop below an acceptable threshold for reliable reception.

Since virtually all of the Philadelphia DTV stations are located in one geographic area, I’d suggest an indoor antenna that’s directional, like the Terk HDTVa. This antenna also has a built-in amplifier that provides decent performance. But that’s only going to help you with the UHF channels. You’ll need to pull up the rabbit ears all the way to pull in VHF stations WPVI on channel 6 and WHYY on channel 12.

Have you considered an attic antenna, if you can’t put anything outside? The Channel Master 2016, which I use on my roof, is reasonably priced and would do the trick nicely for you. If you can’t go with anything other than an indoor antenna, you’ll want to keep it on the south side of your house or near a window to maximize signal strength. Buy your antennas through Radio Shack, as they have a liberal 30-day, money-back return policy. This way you can bring back any antenna(s) that don’t do the job for you.

Hey, Where’d Channel 6 Go?

Q. About a year ago we discussed that as part of the digital transition, WPVI (ABC) was moving their digital signal from UHF back to VHF. I have been receiving digital TV OTA for about 2 1/2 years, and CH 6 had come in perfectly. (Editor’s note: WPVI-DT operated on UHF channel 64 during the DTV transition.)

On June 12, WPVI moved their digital transmission to VHF. Now I get audio dropouts and pixilation several times a minute. I did manage to see a program with the WPVI tech guy explaining that for WPVI one has to extend the rabbit ears. Somehow I cannot imagine people extending the rabbit ears for WPVI and then collapsing them for every other station.

Any suggestions on what I can do? Maybe an antenna amplifier? Do you think the WPVI folks will realize that no one station is special enough to deserve antenna re-adjustment and re-consider the decision to be the only VHF digital station in Philadelphia? Do you know whom at WPVI I could send my experience to?

A. First off, click here for my recent article on reception issues with DTV stations on VHF lowband channel 6. This will cover a lot of the issues involved and bring you up to date on what WPVI has done about it (like raising their power by another 6 dB since the analog shutdown).

I should also mention that WPVI’s engineering department doesn’t feel they are “special” and can inconvenience everyone by moving back to channel 6. According to the station’s chief engineer, at the time the station filed for its final channel election with the FCC, channel 6 was the only channel available in the Philadelphia market that would allow them to replicate the coverage they had with their older analog broadcasts.

As for the rabbit ears issue — yep, you need to have them extended all the way, so that they are close to resonance at channel 6’s frequency of 82 — 88 MHz. A UHF antenna has no gain at this frequency, so you will need more aluminum to pull in the Action News gang. The good news is that the FCC gave WPVI permission to run higher power, which may moderate the problem for you. Let me know if it has made a difference.

Wire You Asking?

Q. RG-6 cable is usually the recommended wiring for all new hookups, but I haven’t seen much discussion regarding RG-6 cable quality. I prefer ‘name brand’ RG-6 cable with a solid-copper center conductor wire, but lately I see a lot of RG-6 cables made with a CCS (copper-clad steel) center conductor. For this new CCS type, the center conductor wire is all steel with a thin outer coating of copper (which I feel is inferior). Often you have to read the fine print to even know if a CCS center wire has been substituted. Otherwise, it can be difficult to tell (sometimes only by looking at the end of a cut cable). Have you encountered this as well, and what are your thoughts?

A. Actually, copper-clad steel isn’t a bad way to go, as it makes the center conductor stronger. Copper is a great conductor, but is very soft and can and does break with repeated bending and stress. Cable manufacturers that make copper-clad steel center conductors are taking advantage of the “skin effect,” which states that as the frequency of an RF signal increases, the signal travels more along the surface of a conductor than through it.

That’s how at UHF frequencies, TV and radio stations can use air waveguide to carry the signal from the transmitter to the antenna — there’s no wire involved. So copper-clad steel RG-6U gives you a stronger, more durable coaxial cable that still presents a low-resistance path to VHF and UHF signals traveling along it.

Blue Musings

Q. Thank you so much for your excellent reviews and in-depth coverage of all things HDTV. I was very interested in your quite favorable review of the Pioneer 09 Elite Blu-Ray player. I am seriously thinking about getting a multi-region UK model (the Pioneer LX91), which is basically the same spec as the 09. I was particularly interested in the below quote from your review.

“Other selections you’ll need to make are the output resolution and aspect ratio (default setting is 16:9). The player can output video at 480i, 4880p, 720p, 1080i, and 1080p resolutions, but only Blu-ray discs will work with all of them. Red laser DVDs will most likely limit your choices to 480i or 480p output, thanks to copy protection bits encoded on the DVD.”

I have always outputted BOTH Blu-ray discs and SD DVD’s at 1080p/24 to my Pioneer Kuro 60” plasma display (with its native resolution being 1080p and 24p capable). Am I right in understanding that it would be better to send SD DVD at 480i or 480p instead of what I currently use, which is 1080p/24 in pixel-to-pixel (dot-to-dot) mode? If you could please clarify this, it would be very appreciated. Kind regards, and please keep up the great work!

A. The question is not whether to have the player scale red laser DVDs up in resolution to 1080p. It’s whether the particular DVD you want to watch will allow you to do that! Many red laser DVDs I’ve tested on BD players won’t play out at anything other than 480i or 480p resolution.

All things being equal, I’d prefer to have the Pioneer player handle the video “heavy lifting” of de-interlacing, motion adaptive correction, and upscaling. But if the copy protection on the DVD won’t allow you to do that, what choice do you have?

More Philly DTV Issues

Q. I view the Philadelphia stations from Paoli. The Roxborough towers are about 13 miles distant, at 97 degrees. As somewhat of an experiment, I jury-rigged the rabbit ears from an old analog set to a new Toshiba set. The set scanned 25 stations and exhibited pretty good reception, although nothing for Channels 10 and 12.

Antenna No. 2 just bought and installed is the Kowatec CS-102, which you liked a lot. It will pull in Channel 10, but not 6 and 12. And oddly, a previously strong Channel 29 is now a blank screen. Overall reception quality seems better, but I realize the nice little CS-102 won't do it all. I need a UHF/VHF antenna, and an indoor model with non-distorting amplifier preferred.

I'd like to pick a good Antenna No. 3 and stick with it. Your archives from several years back include an indoor antenna test. You liked a Radio Shack 15-1862. Among current products, are there any that stand out as possible good performers?

A. You'll need a combination VHF/UHF antenna to pull in WPVI-6, WHYY-12, and the rest of the Philly stations, which are on UHF. Radio Shack discontinued the 15-1862 and its successor, the 15-1882, a few years ago. So far, I haven’t found any suitable replacements that combine rabbit ears with a rotatable bow-tie dipole, backed up by a reflector screen.

The indoor antenna I’ve tested that comes closest in performance is the Terk HDTVa, which is an amplified Silver Sensor (UHF log-periodic antenna) to which a pair of rabbit ears have been added. You also could try combining your Kowatec UHF panel antenna with a pair of rabbit ears through a VHF/UHF diplexer. This would receive both bands separately, but give you one coaxial connection to your TV. Winegard has the CA-8800 for about $15.95 at www.solidsignal.com and it would do the job nicely.

Out Here In The Hills

Q. Reading the Home, Home On The Fringe article in search of the trick to have WNYT reception, and wondered if you would have any suggestions? Our house, with rooftop antenna, is located in Grafton, NY. Before the 6/12 transition, we received only channels 13 and 6, all other local channels were lousy pictures. Now with digital broadcast, an older television with converter box connected, we get channels 6, 10, 17, 23, and 55, but we cannot get channel 13 (WNYT), would like to get the CW as well. Seems odd if they all broadcast from the same tower location. Any suggestions would be appreciated.

A. I’m not sure what type of antenna you are using, but if you are picking up physical channels 6 (WRGB 6.1) and 7 (WXXA 23.1), then you should be good to go with channel 12 (WNYT 13.1). You may need to add a mast-mounted preamplifier and kick up everybody’s signal levels a bit more. Checking on the TVFool.com site shows that the center of Grafton is about 30 miles from the Helderberg Mountain TV antenna farm, over a 2-edge path — the same sort of hilly path that caused knife-edge refraction at the SW Vermont location featured in my article.

That makes for pretty low signal levels, so I’d add the Channel Master 7777 Titan 2 mast-mounted preamp to your rooftop antenna, which hopefully already is a VHF/UHF type. If it’s been up there a while and is getting corroded, replace it with a new model — both Channel Master and Winegard make suitable designs for fringe TV reception that aren’t too expensive. Also upgrade your antenna downlead (coaxial cable) at the same time.

My guess is, at this distance, the mast-mounted preamp should fix the weak signal problem and also pull in WCWN, which transmits on channel 43 (although they identify as channel 45). Channel 55, which is WYPX, broadcasts from 41 miles away near Amsterdam and is more to your west, so if you can pull them in, you should be able to snag WCWN and WNYT as well, not to mention WNYA-DT on channel 15. Good luck!