Interesting take on a TV reception problem, "we'll see"

[67Dart273]

I have a really decent UHF corner reflector on my tower, aimed at a local hill not far away, where all the TV translators are located. I have NEVER had a problem, until some months ago, there was some work being done up there, and I knew that because some channels went dark during part of the day as they had to be shut down. Since then, some channels at some times tile and freeze. A look at the annoying "deep" menu to get into the "signal strength" menu shows "full to the right" signal level. I just don't get it. I called the local Channel 4, and the engineer was no help. So last week I emailed local channel 2, explained where I was and the problem, and got this response:
==============================================================
"Hi Del

When the antenna work you referred to last summer was done, channel 4 moved their translator on Canfield to rf channel 31. KREM's translator is on rf channel 30.

It may be you have an adjacent channel problem.

Something to try is padding down the signal to your TV, we receive our Cd'A translator in Spokane without any problem but that is a relatively lower signal strength. With digital you can have too much of a good thing.

FYI: the Canfield channels that I know of are as follows: KREM ch 30; KXLY ch 31; KHQ ch 18; KSPS ch26; KAYU ch 27."
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What this means is, that they moved the actual channel transmit frequencies so that they are now RIGHT NEXT TO EACH OTHER and are likely overloading my set. I have some in-line attenuators, and will try and find enough tomorrow to "toss" them in line..........one of these girls.........So I'll stick one in there and "we'll see........."

 

[Treblig]

Channel bleed???

 

[pt70]

I've fought with antennas decades ago. I live in a mediocre reception area. In 2004 I gave in to cable. Got the minimum service and the bill was $7 and change per month. They [Comcast] just re-boosted my rates to $40 plus per month! No, I'm not feeling great again.

About 10? years ago the feds took over VHF channels 2 thru 7 [?] and switched them to UHF. They went digital so I had to buy a converter box. My old VHF antenna didn't work well on the UHF channels so I bought a new UHF antenna. I did a test at a different location. The results were so-so.
The antenna is directional, so it has to be pointed at the TV tower.
The TV tower can change the signal direction. Like pointing a horn style loudspeaker at the crowd.
Trees and windows lower the signal strength.
Weather affects the signal as it changes from day to day on weaker stations.
Weak stations will go from clear to pixilated at any time with digital. With analog, the picture would go cloudy for a while, but the sound would still be good.
If the TV towers are in the same direction, your ok. If the towers are in varied directions, you will need an antenna rotor.
Search 'antenna TV' and you will find sites that tell you the location of the channels in your Zip Code area.

 

[RogerRamRod]

antennaweb.org
enter your zip, or actual address for better accuracy. gives compass heading and distance.

 

[67Dart273]

antennaweb.org
enter your zip, or actual address for better accuracy. gives compass heading and distance.

I know all about that. Doesn't help with this problem

 

[67Dart273]

Channel bleed???

That is one term although I've never liked the term "bleed." It matters not what sort of receiver you are dealing with, or what type of signal, or how good the receiver is supposed to be. The fact is, if you take two adjacent frequencies, and start making them strong enough, either by increasing power, moving the antenna, or (in a car) moving the receiver, at some point you will get various types of interference caused by receiver overload.

In this case we have a translator group on one hill, only about 3 mi away, with a fairly good high gain antenna aimed right at the hill. "Lots" of signal. According to the engineer who replied, "it might be" because the one outfit changed channels so that 3 stations are all adjacent in frequency.

Anyhow, it will likely take a couple weeks of screwin' around with attenuators and "evaluation" because this problem doesn't happen every day, nor is it repeatable. It's completely intermittent......always on my favorite shows LOL

 

[DodgeLad]

Try a crappier antenna. One that is less directional and not as much gain.

 

[Treblig]

That is one term although I've never liked the term "bleed." It matters not what sort of receiver you are dealing with, or what type of signal, or how good the receiver is supposed to be. The fact is, if you take two adjacent frequencies, and start making them strong enough, either by increasing power, moving the antenna, or (in a car) moving the receiver, at some point you will get various types of interference caused by receiver overload.

In this case we have a translator group on one hill, only about 3 mi away, with a fairly good high gain antenna aimed right at the hill. "Lots" of signal. According to the engineer who replied, "it might be" because the one outfit changed channels so that 3 stations are all adjacent in frequency.

Anyhow, it will likely take a couple weeks of screwin' around with attenuators and "evaluation" because this problem doesn't happen every day, nor is it repeatable. It's completely intermittent......always on my favorite shows LOL

That's what we called it in the CB craze (1970s) "bleed over" between channels. Must not apply here???

 

[67Dart273]

"Bleed over" is part of the idea, I've never cared for that word. But yeh. Essentially, there is so much signal getting into the TV, that it's (likely poor quality) tuner is not selective enough to "weed out" the nearby very strong channels.

On a side note, I've BEEN to the channel 4 transmitter building, in the analog days, on top of Mt Spokane. There was a set up there---no antenna--on channel 4, and it was nearly unwatchable from all the RF "floating around" LOL I'm told they don't even need to heat the building in the winter very often---there are motorized damper doors and temp controls on the transmitter cooling fans, and in cold weather, they just "dump" the transmitter cooling air back into the building.

I was up there I think 3? times, and once, in a sno-cat--you could not see 20 ft in front of you. I have no idea how the driver found the building. At one point we heard him say "I think this is it" and slowly, out of the blizzard and fog, the building slowly materialized. There is a garage door a LONG ways off the ground, and if the cat can plow it's way to the door, you can drive right into the building

 

[67Dart273]

I found these on the net. It was not a clear day when I was up there LOL

 

[67Dart273]

This is the translator site in question, stolen off the net. You can no longer drive up there (locked) and I have not been up there since about 2K. The towers are WAY busier than I remember

The stupid thing about locking up these sites is that they don't keep the people out on foot or on bikes, and some of them have evil intent. They MIGHT be better off, so far as theft and vandalism, if they let the rest of us drive up there and so to say, maintain a presence

 

[pt70]

67 Dart; thanks for the pictures. I expected to see Jack Nicholson jump out from behind the bushes. [The Shining].

As a kid my dad put up an antenna. Three Boston stations came in well @ 50 miles away. A local station @10 miles away usually had 'ghosts'. We disconnected the antenna feed and with a set of cheapo rabbit ears it produced a clear picture. Never knew why. But when one of the antenna forums mentioned it, a person wrote in and said it was due to a strong signal hitting the antenna and then that was followed by a weaker signal that bounced off a hill and arrived a few milliseconds later. Sounds right to me. Analog signal.

Wow. 3 miles away. ----- Your wife could pick up most of the stations if you bought her the right set of earrings. ---- I'd try turning the antenna in a different direction and see what happens.