OTA Channel blocking

[DSpud]

I live in Laredo TX and I am not sure if the TV Station is broadcasting a bad signal or if My antenna is out of wack. Fox 39 KXOF-TV in HD is very blocky and unwatchable at some points of the day. However, my signal indicator is showing between 84-86% and that the frequency is locked. I have a few other OTA channels between the 30-60% range that are locked in and look perfect. Any ideas?

 

[osu1991]

You may be too close to the transmitter for that station and it is overloading the tuner.

 

[boba]

I live in Laredo TX and I am not sure if the TV Station is broadcasting a bad signal or if My antenna is out of wack. Fox 39 KXOF-TV in HD is very blocky and unwatchable at some points of the day. However, my signal indicator is showing between 84-86% and that the frequency is locked. I have a few other OTA channels between the 30-60% range that are locked in and look perfect. Any ideas?

Using 78045 for Laredo on TVfool ch 27 KXOF(39.1) is 1 edge which indicates possible obstruction of signal. What are you using for an antenna?

 

[DSpud]

Using 78045 for Laredo on TVfool ch 27 KXOF(39.1) is 1 edge which indicates possible obstruction of signal. What are you using for an antenna?

I am using an RCA antenna from lowes. Not sure of the model number but it was about 70 bucks. Its mounted outside, on the roof, where the dish network pole mount. Its a directional antenna facing toward the city, where most of the stations are broadcast from. tVfool does show that this particular channel is broadcast in the opposite direction from the way the antenna is pointing, but I am in the red on the map. The tower is only a few miles away from the house. Its actually the closest tower to the house. Not sure what the obstruction could be between the house and tower.

Also, i have noticed that the channel only does this when its broadcasting HD content. Right now, there is an SD show on and its just fine. I know that sounds odd, but that seems to be the case.

 

[mike123abc]

Do you have an amplifier? It could be overloading the amplifier if too close.

 

[DSpud]

I do not have an amplifier on the system at all.

 

[navychop]

Rotor? If the signal is too strong, try rotating the antenna away. Try turning it broadside to the tower.

 

[DSpud]

I do not have a rotor, but it's currently pointing the opposite direction of the tower.

 

[Mr Tony]

that is probably part of it. I have a VHF only antenna aimed SW for a distant VHF station (72 miles away) and on the backside of it (opposite direction) is my local FOX & NBC (28 miles away on 9 & 11) and I get dropouts even though signal is at 88-92 on those. Would be 100 if aimed at the stations

 

[mike123abc]

It is probably picking up some multipathing.

 

[boba]

I do not have a rotor, but it's currently pointing the opposite direction of the tower.

Why are you aiming N? Zip 78045 from TV fool shows only ch 20 KPXL to the north virtually all other channels are south or slightly east of south by the zip code.

 

[DSpud]

Why are you aiming N? Zip 78045 from TV fool shows only ch 20 KPXL to the north virtually all other channels are south or slightly east of south by the zip code.

I am aiming south-Southeast. the zip code "78045" is too general and actually pinpoints an area well north of my house. There are two stations to my northwest. 8-KGNS and 19 KLDO. 8-KGNS comes in just fine. After all of this, I am not sure I even have a problem, however, Its been coming in perfect all day after blocking for the past 4 days. I guess I will try adjusting the antenna if the problem starts again.

BTW, if you haven't noticed, I love crazy close to Mexico...you should see some of the crazy stations coming out of that country.

 

[boba]

Good Luck. Yes having the actual address plot vs. the zip code plot does make a difference. Zip code shows 19 south of the zip center actual plot is north of your location. You should still be able to aim south and pick up 19 & 8 off the back side..

 

[DSpud]

OK, I am convinced now that the blocking ONLY happens when the channel is broadcasting an HD feed. During the Football game tonight, the channel 39.1, their main channel, was unwatchable. However, I have learned that they also broadcast their HD feed on 31.2, which looks great (and comes in at 98%). So, now I am thinking the problem is on their end, as the channel comes in fine when its broadcasting an SD program (like the local news, which is on now and looks fine).

 

[osu1991]

Have you checked at AVS forums to see if there is a thread for your locals? If there is a thread at AVS someone else might be having the same problem. I'm not sure why it would only occur during the HD feed unless the station was sending out some corrupt data, that is affecting your tuner.

 

[mike123abc]

I wonder if they cut back on the error correction to have more room for subchannels when in HD mode.

But, I think OSU1991 may be on to something. It could be that they have some sort of error or incompatibility with your TV when they take the network feed and compress it enough to fit their sub channels in. If it was a widespread problem they would probably have fixed it by now, but it could just be your brand of tuner.

 

[boba]

Have you tried calling the station and asking to speak to the broadcast engineer. They can be very helpful.

 

[DSpud]

I forgot to mention this happens on both of the TV's in my house that I use for OTA, but admittedly, both are Sony and the newest one was built in 2007, still considered infancy for digital OTA broadcasts. Since they similcast the channel, also in HD, on another frequency that I can recieve and it comes in clear with no problems, I don't think I am going to research this much more. I wonder since they broadcast the channel in HD on two different channels in the market if they already know of this problem and broadcast it on two different channels to compensate. According to tvfool.com, the two channels broadcast on oppisite sides of town. Its just wierd that the one on the other side of town from me comes in better. Thanks for all the ideas. If I have anymore problems, I will call the broadcast engineer if I have anymore problems. Thanks!