I currently have a UHF antenna, my ABC station which I currently get at 100% strength is moving to VHF-LO in Feb 09...Will I need a new antenna?
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Question about UHF/VHF
- Thread starter bkushner
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If your current antenna is not designed to provide gain for VHF low, then almost certainly yes.
But I wouldn't make the investment yet. Many stations that are currently assigned to low VHF after the analog cutoff are still scrambling and petitioning the FCC to find another RF channel after Feb 17. Seems that few of them, if any, *want* to be on low VHF and in at least a few cases, the FCC has been accommodating. I'd hate to see you (or anyone) make the investment to buy a VHF low antenna now and then find out you won't need it because the FCC granted a petition for that station to change their RF channel.
Just to make sure that you get totally contradictory advice I have a CM 4221. it is not known for even VHF Hi much less VHF Low but I was able to get a passable paicture on a low pwered Ch 6 that operated in my area for awhile.
Well, I just looked up TVFool info for Audubon, NJ. It seems close enough to the Philly locals that even a UHF-only antenna might be enough for WPVI (ch 6 after 2/17/09).
Given that, I'd probably just wait and see if his existing antenna can pull in ch 6, assuming that's where they end up when all is said and done...
KNAZ in flagstaff chose to stay on VHF 2 even though they had several opportunities to move UHF
WPVI has not requested a change from channel 6.
You do not have a VHF low band antenna.
You will want a VHF low band antenna.
Attempts to discourage you from purchasing a low band VHF antenna are misguided.
In this case I must disagree -- at least for now. The OP presumably has until 2/17/09 to get the low VHF reception in place. If he tries the existing antenna on analog ch 6 and gets no picture (or a very fuzzy one), then it's time to look at buying a low VHF solution. But again, given how close the OP is to the Philly towers and the strength of signal, it's worth seeing if analog 6 will come in with a decent picture with the existing antenna before making the added investment. I don't expect it will work all that well, but it costs nothing but a few minutes of one's time to test it.
But then again, I'm misguided, so what do I know?
I have a VHF-high on channel 9 that I pickup easily on my Radio Shack U75-R (signal in the low 90's) but I am about 6.5 miles from the transmitter.
I'd say if he's within 10 miles of the channel 6 transmitter, have a look at the analog signal on channel 6 with the UHF yagi and if it looks fairly clear, the UHF yagi would probably work for digital channel 6 in 2009.
I'd say if he's within 10 miles of the channel 6 transmitter, have a look at the analog signal on channel 6 with the UHF yagi and if it looks fairly clear, the UHF yagi would probably work for digital channel 6 in 2009.
It is a regional thing. If you look in the Great Lakes area, most VHF low stations are staying put. In other areas where there are lots of obstructions, VHF low is wildly unpopular.
In the grand scheme, VHF "gets out" better, but is more susceptible to multipath. If there's little or nothing to bounce off of, VHF is the frequency band of choice.
Actually low band VHF is considered very undesirable for DTV and last I saw there will be only 37 DTV stations in the entire country on low-band- less than one per state- and mostly in the mid-west. Low-band has three significant problems for DTV-
1} Low band frequencies (54-88 Mhz) are highly subject to impulse noise from lightning and all sorts of electrical equipment. These pulses just make spots and lines in an analog signal but you can still see the picture. With DTV it disrupts the decoder which is designed to respond to pulse-like signals so the picture and sound break up or disappear.
2) During certain weather conditions- tropospheric ducting (very common in summer) makes low band signals travel into other station's service areas. When a DTV decoder sees two different digital signals on the same channel it becomes confused and doesn't decode either one- so the picture and sound blank out.
3} Transmit antennas must be resonate over the range of frequencies being transmitted. With analog-TV the video information is concentrated near the middle of the channel but a digital signal is spread out across the entire 6-Mhz channel and if the antenna is not "flat" across this range some of the signal is reflected back to the transmitter. This causes numerous problems- including "echos" in the signal that shows up as erroneous bits to a DTV decoder. Making antennas "flat" is much harder at low-band frequencies because 6-Mhz is a much larger proportion of the operating frequency- almost 10% for ch 2- but only 1% for UHF channels.
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While the VSWR bandwidth issue may be true with some antennas, it doesn't matter anymore. All VHF DTV transmitters are solid state. The reflected power in such a configuration ends up in a reject load. The same advantage existed with dual tube-type transmitters.
The problem was more evident with single tube VHF transmitters.
I have a CM4228 and WABC-7 here in NYC currently broadcasts on UHF 45 but I've read they're going back to 7 as well as WPIX ch11 and WNET ch 13. I can get all 3 of the analog stations very well on this antenna so I assume I'll be able to get them when they go digital
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