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The Official Low-Band VHF (2 - 6) Reception Thread

post #1 of 150
8/16/04 at 8:57am
Thread Starter 
It seems there are a half dozen sub-threads (discussions buried within other threads) that pertain to the trials and tribulations of Low-Band VHF reception: Channels 2 through 6.

It makes sense to pull those discussions together. Perhaps if everyone from these different markets who were blessed with a VHF-Low allocation shared their issues and solutions, we could either make VHF-Low viable for everyone, or start a grass-roots effort to eliminate it.

At the least, it will serve as a place to rant and keep the "noise" down in other threads!

Here is a quick listing of the Low-Band VHF frequencies...
Channel 2: 54 to 60 MHz
Channel 3: 60 to 66 MHz
Channel 4: 66 to 72 MHz
Channel 5: 76 to 82 MHz
Channel 6: 82 to 88 MHz

To get things started, here is one advantage of Low-Band VHF (and yes there are more):
- Lower transmitter power required for similar VHF-High or UHF coverage

and, one disadvantage:
- Considerably larger antennas needed, especially for channels 2, 3 and 4

My personal reception issue is with WBBM-DT Channel 3 Chicago. I have only two specific (and inconvenient!) locations indoors, with amplified rabbit-ears fully extended, where I can get this station. I am 33 miles SSW of Chicago in Monee, IL, in a townhome. From the roof of my townhome, the tops of the Sears and Hancock buildings are visible. There are some days where I simply cannot get reliable reception of this station anywhere. Several different household appliances completely kill the signal.

I've read threads about WKYC-DT Cleveland, WWMT-DT Kalamazoo, a station in Fort Wayne, IN (on ch. 4, I believe), and WCTX-DT New Haven. How about other markets? What are your troubles? What have you done to remedy the problem? Are you "pro-VHF-Low" or "pro-VHF-High/UHF?"
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post #2 of 150
8/16/04 at 10:14am
I'm only 11 miles from the Hancock. WBBM still has is a problem for me because of impulse noise. If it sparks, it kills, so to speak. With CBSE on available on D*, I have a choice during thunderstorms of either rain fade on CBSE or lightning on WBBM to kill the signal. The most effective change to lower impulse noise problems I made was to keep the antenna outside so the RFI from throwing a light switch inside has to travel farther and through walls to get to the antenna. An experiment with an attic antenna made WBBM intolerable while all UHF stations were fine. There may be a good use for the low VHF band but digital TV isn't it.
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post #3 of 150
8/16/04 at 10:20am
Quote:


Originally posted by PhilJSmith67
To get things started, here is one advantage of Low-Band VHF (and yes there are more):
- Lower transmitter power required for similar VHF-High or UHF coverage

and, one disadvantage:
- Considerably larger antennas needed, especially for channels 2, 3 and 4

While both of these are true, it also takes more transmitter power than is currently allocated to overcome man made noise, which is what most people are dealing with now. If you see sparkles in a fairly strong analog signal, chances are real good that there is localized man made noise that will make make DT reception tougher than one might think (and computers are just one source of localized man made noise). Enough of these instantaneous bursts will destroy any hopes of a watchable picture.
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post #4 of 150
8/16/04 at 10:49am
http://www.antennasdirect.com/VHF%20...20listings.htm
I think one of the goals of this thread is to actually get antennasdirect to acknowledge that channels 7 and 8 aren't in the VHF-lo band.

How long are the dipoles on your rabbit ears, Phil? Before I got DTV, I shopped around for the longest rabbit ears I could find, so I could get to the 93" needed for a channel 3 dipole. I found a few that had 44" dipoles, but none longer than that. With the 5 inch separation between the ears, I just made it (probably passed it due to end effects).

It's curious that you're using an amp with your rabbit ears. VHF-lo's frequencies are so low that the noise from such an amp would surely be more than the cable losses:
http://www.hdtvprimer.com/ANTENNAS/basics.html (under transmission cable)
Maybe the tuner also has some noise in it. My experiments with the CM7777 at my old house with my rabbit ears didn't yield any more signal quality. I was expecting just a little improvement since the Fusion 2 isn't the most sensitive of tuner cards.

Then again, I had great reception on channel 3 from 32 miles. The secret, I'm realizing now, is antenna height. If you're not 8 feet off the ground, you're not going to get anything, it seems, just 0% signal strength. In addition to that, my old house was at 710 ft of elevation, just past the crest of a gentle hill in the area. Lake Michigan is at 580 feet, give or take, so that's 130 feet above the lake, with just the top of the gentle hill (no more than 15 feet higher than my elevation and half a mile away) in the way all the way to the tower. If you drive (or move to a new house) 2 miles closer to the towers, you drop 60 feet in elevation, and it's all downhill to the lakeshore. So it was like being at the top row of a stadium, reception-wise. I only needed to put the rabbit ears in the attic, and at 723 ft of total elevation, 75% signal quality was a snap (only needed 55% to lock on the Fusion 2).

Now, with the antenna in the living room around 655 ft of elevation at the new house, I get about 35-40% signal quality here on WBBM-DT, which is which way short of a lock or even PSIP data. Analogs are all fuzzy (they used to be obscenely clear for the most part with just a UHF loop, and powerful enough to dominate the fixed-pattern noise on the Fusion 2's analog half.), and there are 2 2-story houses in my signal path that are graded 5-10 feet above this house to boot (it's just a very tall ranch here, about a 24 foot roofline). For the time being, I aim a silver sensor in between the gap the 2 roofs leave to get the best signal quality on my UHF station, but for channel 3, I need more definitely more height and probably more gain. I'm thinking 5 element cut-to-channel minimum with my current signal quality. I still haven't totally figured out why the signal quality is so low. It could be from multipath, in which case, I'd need a new Fusion card with a 5th-generation tuner. I don't think I can overcome it with gain alone, but I'd love to be wrong.
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post #5 of 150
8/16/04 at 10:53am
Ah yes, I almost forgot about impulse noise. I had various electronic gear that would be worth 5-10% (1-2dB) in noise. Things like my fixed wireless transceiver, CRT monitors, old computers and the occasional blender would all hack off enough signal all by their lonesome to break up my signal or at least take it to the threshold at my old house. Put any two together and it was lights out WBBM-DT. Putting the ears in the attic helped, and I'm sure getting them outside would have helped more.
I guess it's a good thing that WBBM-DT is petitioning to go to 4.4kW from their current 3.7kW, I'm sure it'll help such matters.
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post #6 of 150
8/16/04 at 12:19pm
Thread Starter 
Quote:


Originally posted by Rack
... get antennasdirect to acknowledge that channels 7 and 8 aren't in the VHF-lo band.

LOL!

Quote:


How long are the dipoles on your rabbit ears, Phil? Before I got DTV, I shopped around for the longest rabbit ears I could find, so I could get to the 93" needed for a channel 3 dipole. ...

I haven't measured them, but they're pretty long, which is why I bought this RCA/Thompson antenna. Maybe 6 to 6½ feet? But 72" is probably only 30-50% effective for Channel 3.

Quote:


It's curious that you're using an amp with your rabbit ears.

It's a built-in amp; I have it dialed down to the minimum. Unfortunately there is no "bypass" setting. I was tempted to open it up and bypass it myself! I really only need the "ears" not the amp.

With the gain turned all the way down, there doesn't *appear* to be any cross-modulation or other nasty products on any of the analog VHF or UHF channels, but there could still be some noise I can't visually measure.

Quote:


Maybe the tuner also has some noise in it. ...

The tuner I am using is a Sasem OnAir USB HDTV tuner. Originally this tuner indeed was generating its own noise, and lots of it, up to about 150 MHz. I eventually traced it down to the stock power supply. Powering the tuner with a regulated 5VDC 3A power supply on my bench completely eliminated the noise. Now, the Sasem tuner seems to be almost as sensitive as my portable "DXing" TV for both VHF and UHF.

The PC I am using is a new Dell laptop. I've probed around it with a portable on channels 2 and 5 and it seems that the noise emissions are low. The USB cable seems to emit nothing, either.

Quote:


Then again, I had great reception on channel 3 from 32 miles. The secret, I'm realizing now, is antenna height. If you're not 8 feet off the ground, you're not going to get anything, it seems, just 0% signal strength.

Bingo. I get zero zilch on the first floor (coincidentally, ch2 on a watchman gets very little, too). On the second floor, I get reception (about 2dB above lock) at the open area of a center staircase, and weaker reception about 1dB over lock near the raise ceiling in one bedroom. Everywhere else on the second floor yields "signal" around 5dB; basically the tuner is "getting something" but the bit-error rate is extreme. In both of the "hotspots" WBBM-TV ch2 and WMAQ-TV ch5 are clear, and surprisingly have little to no 60Hz static, and no multipath. Sometimes I even snag WTMJ-TV ch4 and WITI ch6 in those hotspots.

Fortunately, my townhome is in a slightly elevated area of Monee, with the Sears/Hancock sticks visible from the roof. My prior house was another 15 miles south in Manteno, where the faint signal of WCIA Champaign was usually stronger than the whisper of WBBM-DT.

On most of the second floor, all UHFs are strong. WXFT-DT and WCIU-DT are the most finicky, but still far easier to get than WBBM-DT. On the first floor it's tough to find a hotspot common to all the UHF stations.

Quote:


I'm thinking 5 element cut-to-channel minimum with my current signal quality. I still haven't totally figured out why the signal quality is so low. ...

You can't beat an antenna cut to size! After reading your post, I'm considering putting a dipole in the attic. The formula I had was for a dipole cut to 90", and a 95" reflector 38" behind it. I won't get around to that for a few weeks though. The easiest thing to do is hack that RCA antenna to bypass the amp.

This sure seems like a lot of work for one channel, when for UHF all I have to do is stick a bowtie right on the tuner and aim it north!
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post #7 of 150
8/16/04 at 12:41pm
The problem is that the FCC is assigning powers far too low to the
low VHFs.


If the digital station was at the same power as the standard
low VHF analog (i.e. 30 kW, as they are rated differently) it would
work better. If it were truly adequate power, say 100 or 200 kW
(rated as digital always is) it would work fine. Sure, this would
require a bunch of power out of the transmitter, but it is
doable.

Doug McDonald
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post #8 of 150
8/16/04 at 1:05pm
Thread Starter 
I agree, and 30kW from WBBM-DT would sure be nice. But, my guess is that the FCC would never let that happen with a HAAT of around 1500', not without completely revamping the rules by which they assign ERP levels to these stations.

Imagine if BPL were to get a green light! Put THAT in the big "disadvantages" column!
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post #9 of 150
8/16/04 at 5:20pm
I watch WCTX-DT almost every day, and it has always been on Channel 39, for as long as they have been on the air! Connecticut Public Television has proposed to place a DTV station in New Haven on Channel 6, but, so far as anyone can tell, it hasn't materialized yet, and WEDW-DT from Bridgeport is strong enough to cover the New Haven area, anyway.
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post #10 of 150
8/16/04 at 7:24pm
I'll be curious to see how low band VHF will do if allocated reasonable power levels.

The problems of large antenna size, undesirable propagation (ie E-skip and tropo) leading to co-channel interference, and sensitivity to impulse noise IMO outweigh the slightly better propagation of UHF over VHF to outlying areas and power advantages. Better to have good reception in a 55 mile radius than lousy reception in a 70 mile radius.

Of course those living 70 miles from the transmitters are free to disagree with me.

I will wager that very few stations with low VHF analog assingments and UHF digital assignments will choose their VHF station after the analog shutoff.
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post #11 of 150
8/16/04 at 7:59pm
http://www.usahardware.com/inet/shop...ni/mant250.htm
This is the antenna I used for WBBM-DT 3. Nice 44" ears, 93.5" max end-to-end when fully horizontal, no amp, and inexpensive. Just make sure to twist the UHF portion around a couple times to get some common-mode rejection in the internal twin-lead, if you're going to use it for UHF, too.

Then again, twin-lead dipoles are very cheap to make, too.
I was thinking of trying some steel tape measurers as a very temporary director and reflector. It's crazy enough to work, right?
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post #12 of 150
8/17/04 at 4:31am
Off topic, what kind of signal meter does the Sasem have? That's the one thing that kept me from buying it; I have no idea if it has a signal meter. Screenshots preferred. ^^

I have WBRA-DT on 3 here. It's 79 miles from me at 7.25 kW (but it's directional, so I only wind up getting 3 or so in my direction).

My biggest problem is e-skip. I'm so far from the transmitter, that any co-channel interference at all just wipes it out. It's my weakest signal to begin with. I don't seem to have the electrical noise problems (though I do have them with the Raleigh analogs).

I've been told that WBRA-DT actually has a 30 kW ERP transmitter sitting on Poor Mountain, but they're running it at 1/4 power. I'm told they'd love to put it up to 30 kW, but that the FCC wouldn't give them more than 7.25 kW directional.

They seem to want to stay on 3 simply because it's cheaper, but people won't be able to get WBRA-DT if it stays on 3. Failure to move to a high-VHF or UHF will hurt them in the end.

- Trip
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post #13 of 150
8/17/04 at 7:59am
I'm glad this thread was started. Last week I ordered a 10-element cut antenna for Channel 5 (10dB gain) and a Winegard AP-3800 (VHF only pre-amp, 29dB). I installed it on the peek of my tallest roof with a 3 foot tripod on a 5 foot mast. The peek of the roof is about 30 feet. The total RG6 run from the preamp to the power source is 50 feet. The station I'm pulling in is WCFT-DT in Tusculoosa with a ERP of 10kW, and I'm 94 miles from the tower.

During the day, the signal fluxes a lot. It goes from 0% - 32%, back and forth. I've been testing it the past 4 days, and it seems to be watchable after 5-6pm, it then fluxes from 21%-36%, which does drop the signal for about a half a second, a little annoying. After 7-8pm, things get a lot better. The signal fluxes from 32%-54%, with occasional glitches in the picture, but the sound is fine. To me, this is totally acceptable since I have no other way to pick up ABC-HD, and I've done all this for MNF which won't start until 8pm for me.

But I'm the type of person who will keep tweaking it until it's perfect. So far, I've tried a RS FM-trap (though the pre-amp has a FM trap built-in), and I've tried a RS varible attuenator. Both did absolutely nothing to my signal. I thought it was a little strange that the signal stayed the same with the attuenator in-line maxed, at it's lowest setting, or taken out of line.

I wasn't aware of all the man-made interference regarding low-band VHF signals, and I do have my HTPC (MPD-120 MyHD) is right where all my AC outlets are, which of course is where almost everything is connected.

If anyone has any hints or tips, I'd appreciate it.

BTW, I'm located in Florence, AL, and the VHF antenna is not combined with my UHF antenna, they are both connected to the MyHD card serperately. Also, with my Fox affiliate at 60 miles out, channel 41, it's signal fluxes all the time with the MyHD card. It fluxes between 25%-40%, but I very rarely get a glitch in the picture, and and never drops the signal. I though it was strange the VHF channel gets a higher signal percentage and doesn't register to drop below 25% in the evening, but I get more glitches.
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post #14 of 150
8/17/04 at 8:00am
Thread Starter 
I can't provide a screen shot because I'm not home where the tuner still is!

It's very simplistic though... The tuner itself has a red LED on it, which I whimsically call the "idiot light." When the LED is on, there is either no signal or it's too weak to lock. If it's off, the tuner is locked. If it's flickering, the tuner is at the threshold of locking.

There is a signal reading in dB shown with Sasem's controller program, but I'm guessing it's an inverse calculation based off the bit-error rate. The program will either read "No Signal" if nothing at all is detected, or it will read something between 2dB all the way up to about 32dB, with approximately 16dB being the level at which a lock occurs.

The LED is the most responsive, in real-time. It allows me to rotate a bow-tie to see the "edges" of a usable signal and center it in between. It's also the quickest way to search for a hotspot. The dB readout tells me how "hot" the hotspot is.

There are several things I wish the tuner had. First, I wish it had a multi-LED meter in place of the single "idiot light." Second, I wish the signal readout was similar to what some wireless 802.11 cards have, where they read the true signal level and either "quality" or "noise." I also wish the software could output sound, like a Geiger counter, so I could hear it from another room or set a phone near it while listening with a cell phone at the antenna.

The tuner's primary intended purpose is for laptop users to be able to tune DTV signals and record shows, with portability in mind, which is probably why the signal instrumentation is simplistic. It sure is nice to be able to record SD or HD shows in a hotel room on a business trip, and watch them later on the return plane trip, or in the evening after Day #2 of a dry, week-long conference. I've been to hotels in cities where the local WB, UPN or even Fox station wasn't on the hotel TV, too, and had to miss shows. For Spanish-speaking travellers, fat chance that the local Univision, Telefutura, Telemundo or Azteca America affiliates are carried.

That brings me to another disadvantage about VHF-Low. Portability. I don't have a problem stuffing a tuner and bowtie into my laptop bag. I even have a pocket-sized amplified "rabbit ears" antenna from a few years ago at RatShack that works *great* for VHF-Hi and UHF. But, its three-foot wingspan is inadequate for channels 2 through 4 or 5. I am certainly not going to pack an antenna the size of a 4-slice toaster into my luggage, only to find out that the VHF-Low signal I want can't punch through the hotel walls anyway. 80 MHz seems to be the bottom of what gets into a lot of today's buildings, and it's also about the lowest frequency for which a TV antenna remains "portable."
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post #15 of 150
8/17/04 at 9:09am
Thread Starter 
10kW on Channel 5 with a distance of 94 miles is really pushing the limits.

I'm guessing the VHF amp doesn't have adjustable gain. 29dB is a bit on the hot side. But then, if the antenna is cut specifically for 5 and playing with an attenuator has no effect, you're probably not getting any cross-modulation or interference. You're just getting the station you want with a fixed signal-to-noise ratio.

Without any of those other parasitic products, the s/n ratio will remain the same no matter what you do along the feedline; it's a direct result of the antenna itself. The only thing I could possibly suggest is getting another antenna exactly like the one you have and stack it. That will give you a tighter directional vertex, effectively increasing the signal of WCFT-DT. It would also be a costly experiment, though.
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post #16 of 150
8/17/04 at 9:15am
Thread Starter 
BTW Rack, that's a nice little antenna for $15. I opened up my RCA amplified antenna and, unfortunately, I would have to do serious surgery on this thing to bypass the circuit board. The coax connectors are actually edge-soldered right onto the board with LOTS of solder, and there isn't room to mount an extra connector.
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post #17 of 150
8/17/04 at 11:55am
Quote from one of my other postings.
"The V4 Low Band VHF antenna was purchased from these guys "http://www.antennasdirect.com". This antenna is channel 2 - 6 specific. It is shipped with a balun box to combine this antenna with an existing antenna. I stacked the V4 on top of my current VHF/UHF antenna using a 12" pole extension. Balun box splits and combines the two antennas to prevent overlap."

I installed the second antenna a several months ago on top of my primary one (120 mile Radio Shack). This combo is working very nicely feeding the entire house through a one - in - four out amplifier (~32db gain) serving NTSC and ATSC sets.
During stormy weather there are still dropouts even after optimizing antenna direction. I have had discussions with many people regarding ATSC (NTSC also) and there are some common denominators here.

Multipathing and actual antenna location (yours).

An old TV repairman mentioned a technique they used to find a good location on the roof for a customer's antenna. "Using a portable TV connected to the antenna in question (long enough lead-in), walk around the roof until you get the most channels and strongest strength".

He said there will be "dead spots" with little or no reception (stay away from those). I have not tried this because I already installed my antenna in the logical spot (chimney). At this location I could move the antenna to any of the four (4) corners. This though would be alot of work but, I'm out of choices.

Martin
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post #18 of 150
8/17/04 at 2:30pm
Thread Starter 
I've used that technique to search for hotspots and it works very well. It's also an excellent way to rule out feedline/amplifier problems.

taz, with your Channel 5 antenna, have you already surveyed where the hottest signal is on your roofline? Unfortunately, it will be considerably more difficult with a DTV station unless you wait five years until the first handheld ATSC TV.
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post #19 of 150
8/17/04 at 2:52pm
Phil:

Could you get me some pictures of the tuner and its idiot light, as well as caps of the signal meter when you get a chance? Also, does it have any outputs on it other than the USB? Like, could I attach it to my TV?

- Trip
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post #20 of 150
8/17/04 at 3:42pm
Quote:


Originally posted by PhilJSmith67
I've used that technique to search for hotspots and it works very well. It's also an excellent way to rule out feedline/amplifier problems.

taz, with your Channel 5 antenna, have you already surveyed where the hottest signal is on your roofline? Unfortunately, it will be considerably more difficult with a DTV station unless you wait five years until the first handheld ATSC TV.

I moved it around to about 5 different places, thank God it's on a tripod, it's much easier to move around. Where I have it now was the only place I could get a good enough signal for picture/sound (at around 5pm). I have two very large trees in the front yard and this position was the only place I could get the antenna to aim between the two trees.

Like I said, I'm very satisfied, but I'm also more than willing to tweak it. Our spectrum-analyzer at the station is being repaired right now, but I don't know if that would help any even if I had it.
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post #21 of 150
8/17/04 at 3:47pm
Thread Starter 
Not easily... I'm di-cam-impaired!

Basically, the "idiot light" is a red LED in the front panel, at the opposite edge from the green "power" LED visible in this pic:




Here is a snapshot of the tuner controller software. Of course, without having the tuner connected right now, it says "No Signal"; I am playing back a recorded transport stream of WTTW-DT. In place of "No Signal" it would say 30.45dB or whatever the signal level is.



USB 2.0 is the only output. Basically, the unit sends the raw ATSC transport stream via USB to the Sasem software (which uses InterVideo's MPEG-TS decoder).
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post #22 of 150
8/18/04 at 12:43am
Quote:


Originally posted by PhilJSmith67
Imagine if BPL were to get a green light! Put THAT in the big "disadvantages" column!

I presume you're referring to "broadband over power lines," and low-band TV viewers aren't the only ones complaining. When the utility in Cedar Rapids experimented with BPL recently, Ham radio operators screamed bloody murder and threatened to sic the FCC on them.

I never noticed any appreciable effect on the analog Channel 2 we have in town, but I've never really got that channel very well in the first place -- and since getting DT equipment in April, I watch their DT 51 instead.
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post #23 of 150
8/18/04 at 6:45am
Thread Starter 
Testing has proven to be a mixed bag as far as the service itself, too. Any system that relies on unshielded lines to transmit digital signals is going to be quirky, especially over a power grid that is riddled with faulty insulators and transformers spewing noise from DC to daylight.

Pro-BPLers mock the naysayers by classifying them as tiny group of shortwave and amateur radio zealots experimenting with an ancient technology. Of course it's amateurs' research that has put much of today's communication technology in place. And, even beyond that, there is a heck of a lot more going on between 2 and 80 MHz than just a few old farts shooting a QSO via CW.
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post #24 of 150
8/18/04 at 8:22am
Quote:


Originally posted by PhilJSmith67
Testing has proven to be a mixed bag as far as the service itself, too. Any system that relies on unshielded lines to transmit digital signals is going to be quirky, especially over a power grid that is riddled with faulty insulators and transformers spewing noise from DC to daylight.

Pro-BPLers mock the naysayers by classifying them as tiny group of shortwave and amateur radio zealots experimenting with an ancient technology. Of course it's amateurs' research that has put much of today's communication technology in place. And, even beyond that, there is a heck of a lot more going on between 2 and 80 MHz than just a few old farts shooting a QSO via CW.

ProBPL people also tend to have no access to high-speed internet--such as me for example--and will probably not have access to it anytime soon.

- Trip
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post #25 of 150
8/18/04 at 8:54am
Thread Starter 
I was told back in the 90s that local phone companies would have to provide DSL at competitive prices to all customers by the end of 2005. What ever happened with that? Is it still a mandate? I don't even know who mandated that originally, and haven't heard anything about it for years.
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post #26 of 150
8/18/04 at 7:00pm
Quote:


Originally posted by PhilJSmith67
I was told back in the 90s that local phone companies would have to provide DSL at competitive prices to all customers by the end of 2005. What ever happened with that? Is it still a mandate? I don't even know who mandated that originally, and haven't heard anything about it for years.

Go tell that to Verizon for me. I'm out in the sticks and BPL appears to be the only chance of getting anything in the next 2 years outside of satellite, which is far too expensive and has too much lag for webcam, etc.

Unless there are drastic changes soon, I'll be in college before broadband is readily available to me.

- Trip
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post #27 of 150
8/18/04 at 9:40pm
KVBC-DT (3-1) in Las Vegas broadcasts their digital signal on channel 2. Some people have reception with bunny ears, but I had to get an outdoor antenna as it was the ONLY station an indoor absolutely would pull in no matter how I contorted many antennas. If you can't get an antenna on your roof it's been suggested to make some very large home made dipoles preferably at the wavelength of the signal you're tring to receive. For channel two you're looking at over seven feet horizonally across which is very impractical, but what is necessary to get the gain and multipath rejection for a signal lock.
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post #28 of 150
8/19/04 at 7:16am
Thread Starter 
GeorgeLV, how far are you from the KVBC-DT transmitter?

BTW, last night with a never-ending lightning storm that literally lasted three hours, my tuner spent as much time "unlocked" from WBBM-DT Chicago than otherwise. All this, after finding a spot in my house where I get 21dB signal (over 16dB threshold), as opposed to 18dB in the old spot.

Even with the closest lightning strikes, I had only three hiccups, which amounted to very brief pixelation, on the UHF stations using an indoor bowtie.
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post #29 of 150
8/19/04 at 10:00am
Phil, a mere 16 miles from the tower farm smack in the center of the city. Skyscrapers tear up low-band vhf forcing me to use a fringe antenna to get a watchable digital signal. There have been t-storms, flash flooding, and monsoon winds this past week in Vegas, but the dropsouts I've seen obviously originated at the network (because they repeat in the same spot when NBC loops their olympics coverage).
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post #30 of 150
8/19/04 at 10:02am
I realized my grammar might be confusing, so to clarify, I'm in the center of the city, the tower is on a mountain range 16 miles away.
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