Channels 2-6 after Feb 2009

[Waterfallguy59]

It looks like in Michigan all DTV stations will be off the VHF-L (Channels 2 - 6) band other than WBKP channel 5 Calumet, and WGVK channel 5 Kalamazoo after 2/2009.

Was this a edict from the FCC, and are other states doing the same ?

Joe

[Robert Grant]

IMHO, you can add WLMB-DT 5 to the list.

Though it's city of license is Toledo, their TL is just north of the MI state line near Jasper in Lenawee County.

In general, stations are trying to get off of lowband unless they are convinced their OTA audience is already gone (rural areas, where one needs to get cable or satellite to get more than ONE station, have nearly 100% subscribing), or the opposite - urban areas where the temporary DTV channel is out-of-core and only their original lowband channel is open (e.g. WPVI-DT 6 Philadelphia).

Rob

[cd637299]

I have a question....

Are so-called outdoor "HDTV antennas" cut to include lowband V? Something tells me that they are not, because of so few TV stations on DT in the lowband.

If they are not, these stations in the lowband are getting a dirty deal.

cd

[Robert Grant]

In general, ANY antenna being marketed today is being marketed as an "HDTV" or a "digital ready" antenna - there's really no difference in the antennas, but it would be suicidal to market an antenna if anyone *thought* the antenna were inadequate for digital.
The same thing happened in the mid-1960's - all existing TV antennas were suddenly repackaged as "Color TV antennas", while all cameras had "Color" lenses.
There are SOME new "7-69" antennas coming on the market, and these could present a problem for lowband DTV stations in the future. For now, I don't think they are selling well - all of the examples I've seen so far are overpriced.
Many antennas being sold for digital TV are UHF only (they, too, existed before the digital question ever came up). These are already causing headaches in markets where highband DTVs exist and will be a bigger problem come 18th February.

The biggest problem with lowband DTV is that the coverage curves (and thus the RF power limits) on lowband were based on an ideal outdoor environment, counting only natural noise.
In the real world - especially INSIDE real homes and businesses, RF noise is immense, from computers, battery chargers, even from televisions themselves (the recent transition from bulky 60Hz transformer power supplies to sleeker and cheaper switching power supplies is particulary damaging). Reception of analog television on lowband is already hammered.

Lowband DTV could work well if coverage were based on overcoming noisy environments, and stations put out ERPs on the order of 500kW or so (this is much more expensive in lowband than on UHF, since a lowband transmitting antenna with the gain found in UHF antennas would be necessarily enormous).

Rob

[antennanut]

Today for analog, I believe the normal maximum ERP for low band VHF is 100,000 watts, and for high band VHF is 316,000 watts. Many analog UHF stations run 5,000,000 watts. However, I think wattages for DTV broadcasting are typically running 50,000-60,000 for high VHF and 1,000,000 for UHF. Haven't seen enough low VHF to remember what seems to be typical. There is an uproar about the many households that will lose OTA signals in February, and yet the transmission wattages are a lot lower. I'm guessing the reason for lower power is in the way DTV signals are broadcast and received, but it sure seems to be a significant difference. Perhaps it just isn't practical, but if the power for DTV signals more closely approached the analog power, would there be a controversy over losing reception?

[cd637299]

I cannot answer that....maybe Doug W9Wi can.....but apparently, because channels 52-69 will be taken away, they only way for the existing stations to cram into the smaller bands, would be to lower their power....

I know that in FL there'll be ch 7's in 4 cities---Miami, Tampa, Jacksonville, and Panama City. Co-channels in Tampa & Jax would have been a no-no in analog-land.

So apparently, the reach will not be as much (cable & satellite compaines must be drooling at Feb 2009!). That being said, I have not had cable in almost 15 years, and since I bought 2 converter boxes last week (Insignias, thanx to club info), I have no intention to change.

cd

[static1701]

I think this is going to be another fiasco just like when the government meddled with toilets. (Around here, people still drive to Canada to buy a decent toilet)

I know someone that lives on the second floor of an apartment, 40 miles from the transmitters and could get a "watchable" analog signal but when he tired digital, he got almost nothing and what he did get had many drop outs. He tried 2 different indoor antennas including the Silver Sensor and could not get a decent signal. I gave him a 4 bay antenna that I made and it did the trick, but it is big and ugly (He hides it behind a chair).

The problem with the change to digital is people are going to loose the ability to watch free television. People in apartments, retirement homes, etc. Indoor antennas are not going to get the job done. I would rather have a fuzzy watchable picture then a nice black screen with a "no signal" message.

If the signal power goes up after the analog shutdown so that people with indoor antennas can watch tv, then I think things will work out. Otherwise, all the government did was give the big cable companies a huge present.

[cd637299]

Yeah....DXing aside, my family can tell all of you that I was a TV junkie as a kid....aside from the occasional sporting event and any DX opening, I am not missing anything......Even when I'd be at a hotel or family member's house to watch cable, there isn't much there either for me.

The evolution of TV Land is sickening. It started out as a great baby-boomer channel. But because of serving the buying demographic, they have to (have to?) skewer younger now. RTN or a similar classic-TV subchannel has not made it to Miami yet, but hopefully there will be sumpn to have me tune in.

But I digress....

Now that DTV channels can offer a wider array of programming, it's time that they take advantage. But I am not holding my breath.

cd

[Waterfallguy59]

I am looking forward to 2-2009, looking at how DTV Channel 7 in Michigan will shape up. Attached is a map I cut/pasted from the FCC TV query map web site. I crudely added the finished parts of the coverage area for WJBK & WOOD. Someone with a good outdoor antenna in the Okemos/Williamston area (east of Lansing) and in the 15-20 mile overlap of WPBN with WOOD area (north of Grand Rapids) should get some interesting DX'ing.:)

[Robert Grant]

The maximum power levels for DTV were set lower than the maximums for analog TV because the amount of power to produce a perfect picture in digital is far lower than the power needed to deliver a perfect picture to the same distance in analog, where any noise must be overpowered by signal to eliminate "snow".

Any old ham could tell you how much less power is needed to operate code (which, BTW, is actually a primitive form of digital transmission) than phone.

Problem for us DXers is, if you merely want to get ANY picture at all, or just enough to make a logo out of the snow, analog requires less power. The mass market, however, has no purpose for a barely-watchable picture.

The original limit for UHF DTV was to be only 200kW. Many VHF stations complained that the UHF signal would not carry as far as their older VHF signal did, and can now use up to 1MW. This actually only increases their range a few miles at the most (the Earth is still in the way), but helps them be received with indoor antennas, and, for us DXers, really improves their performance when trop is in.

A big problem with the power limits with lowband VHF (and, to a lesser extent, highband VHF) is that they were based on the use of outdoor antennas and lower levels of artificial noise from consumer products. Stations are already aware of this, hence WJBK is asking for 60kW erp when the "official" calculations state 3.5 kW "should" serve the market!

Rob

[antennanut]

Good info - thanks Rob.