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fstr
8-Oct-2012, 6:50 PM
I am losing what precious little hair I have over this...
About 10% of the time - very sporadially - I lose signal and cannot watch anything. Most of the time I have superb signal strength. There is no specific time this happens except it seems to happen more often on Sunday nights and NOT when it is overcast/raining (when you would expect worse signal)

So here is my report:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d2df95f9248466d
All channels except 2 are in the green (the other 2 are yellow)

I have a Winegard HD7694P in the attic of a 2 floor home. It points out the side of the roof. No metallic insulation/underlayment etc and don't have aluminum siding.
From the antenna I run a continuous (no connections) 50ft coax to a Channel Master CM3414 Distribution Amplifier. From the CM I run 4 - 3ft coax to 3 HDHomerun's (1 old version and 2 new versions). The Amp and HDHomeruns are on a UPS.

I am not a newb to antennas - I cut the cord a loooong time ago. A year ago I moved from Chicago-burbs to Nothern Virginia-burbs and since then I have struggled. I tried a few different pre-amps and without amps, and also with a DB4. Also tried a 1296F attenuator

But my current setup has excellent signal 90% of the time, so I'm thinking interference.
As a side note I also have issues with my garage door opener sporadically not working - which points me back to interference. I just don't know how to find the interference or isolate myself from it.

PLEASE HELP!!

No static at all
8-Oct-2012, 7:02 PM
Hello neighbor,!! Are you losing all channels when this happens? Are you using an FM trap? I'm guessing you live somewhere near Annandale?

GroundUrMast
8-Oct-2012, 7:03 PM
Do you have a 'spare' antenna lying around? The DB4 perhaps?

If so, can you set up one tuner (TV or HDHR) fed by the 'test' antenna, barefoot (no amplifier)?

Any aircraft in the area? A freeway or road with occasional large truck traffic?

fstr
8-Oct-2012, 9:36 PM
Hello neighbor,!! Are you losing all channels when this happens? Are you using an FM trap? I'm guessing you live somewhere near Annandale?

Hi bud - good to see a local on here , maybe you know of something local that is up with the signal? I'm in Burke just outside Annandale.
Yes, I lose all channels
I am NOT using a FM trap

fstr
8-Oct-2012, 9:44 PM
Do you have a 'spare' antenna lying around? The DB4 perhaps?

If so, can you set up one tuner (TV or HDHR) fed by the 'test' antenna, barefoot (no amplifier)?

Any aircraft in the area? A freeway or road with occasional large truck traffic?

Im not close to a freeway or large trucks, nor airport but have the regular overhead jumbo jets high up

It's normally difficult to work on the issue because it needs to pop up - but it just so happens that now it is happening. (lucky me)
So I routed the coax from the antenna just to one tuner. So I have a solid 25ft coax running directly from the antenna to 1 tuner - nothing else in between and I get exactly the same signal asmy "regular" setup

No static at all
8-Oct-2012, 9:45 PM
Does the outage last about the same amount of time when it occurs? A few seconds or minutes? Are you in a townhouse.

No static at all
8-Oct-2012, 9:51 PM
Does the problem go away after 10:00 @ night?

fstr
8-Oct-2012, 10:10 PM
I'm in a single family home.I have not been able to find any sort of pattern ito length, time of day/week. I'm not sure about the 10pm thing. As I was trying a few things just now it went away again.

fstr
8-Oct-2012, 10:11 PM
One of the things I just tried was the attenuator again - Only reduced the strength, but did nothing to the quality

teleview
8-Oct-2012, 10:27 PM
The first place to look for interference is your own location , the most common interference producers are other electronic devices , computers , radios , communications equipment and etc. , and other devices , fluoresent lights , any other type and kind of lights , water softeners , sewing machines , washers , dryers , or any other type or kind of electrical/electronic device.

Recently , a question asker was having problems and discovered it was the Whole House Fan. Some years ago the Whole House Fans were popular , A large section is cut out of the ceiling and this Huge fan is installed with moving louvers that open and close , it creates a tornado like vortex in your house , I have always thought it is crazy idea , I would go to peoples homes and with much pride they would switch these on and and you had better hang on tight.

Any way when he switched on the Whole House Fan the Tv reception would go out.

Next it is the neighbors , with all and more that is listed above.

Next it would be communications equipment around the area that is suspect.

Next it would be Ham radio operators , although this is very rare now days.

When the interference is happening , does it effect , AM and FM radio reception??

Look up the garage door opener on the internet and find out what operating frequency of the remote control unit is , and post the digital/analog frequency/s here.

No static at all
8-Oct-2012, 10:27 PM
GroundUrMast's point about the air traffic has me thinking that could be the problem. You are directly in the path of incoming aircraft when the winds are from the north, which they are right now.

I experience detrimental effects from Reagan Airport here & it always ends around 10 when traffic ceases. It affects VHF 11 & 13 with split second interruptions every few minutes, & it can be annoying.

GroundUrMast
8-Oct-2012, 10:38 PM
Are there trees close in? If so, how close, how tall, how many & what type?

Just a little wind in the branches can tip the balance... but my experience with this is that the effect is brief, not minutes of outage.

fstr
9-Oct-2012, 1:51 AM
I go from perfect signal to crap - and it lasts for minutes or hours. I am surrounded by tall trees, but then you would expect less problems in the winter and not the type of interference I'm having. I have investigated all the stuff in my house (short of tripping breakers though). Just not sure how I can investigate the rest of the stuff in the neighborhood.

teleview
9-Oct-2012, 2:26 AM
As a test , install the antenna above the roof and run a coax from the antenna to the Tv with no antenna amplifier , couplers or splitters.

What is reception like now??

Is Am radio and FM radio effected also??

_________________
Getting closer to the Truth helps in the middle of the day.

GroundUrMast
9-Oct-2012, 2:33 AM
I go from perfect signal to crap - and it lasts for minutes or hours. I am surrounded by tall trees, but then you would expect less problems in the winter and not the type of interference I'm having. I have investigated all the stuff in my house (short of tripping breakers though). Just not sure how I can investigate the rest of the stuff in the neighborhood.

One TV failing could back feed interference into the others. Isolating one TV to a test antenna with no amplifier would be my next step. If all TVs fail the same in this configuration, it suggests interference via an over the air path. If only the test TV fails, you're closing in on the culprit. If all but the test TV fail, you're still making logical progress, one of the TVs or a common part in the cabling is suspect.

teleview
9-Oct-2012, 3:41 PM
In the google search box type in , emi testing services , rfi testing services.

Ask them lot's of questions. They have a lot of answers because they do a lot of testing for big and small companies and corporations , Tv stations and etc. and know what local and area situation problems are.

And you can also contact the Big Tv stations , their engineers have test equipment and part of their job is to go out 'in the field' and do testing of the reception and interference problems.

Many Tv station engineers like to get out in the homes to check the reception out , it's fun for them.

fstr
9-Oct-2012, 4:57 PM
One TV failing could back feed interference into the others. Isolating one TV to a test antenna with no amplifier would be my next step. If all TVs fail the same in this configuration, it suggests interference via an over the air path. If only the test TV fails, you're closing in on the culprit. If all but the test TV fail, you're still making logical progress, one of the TVs or a common part in the cabling is suspect.

I do not have my antenna running to TVs. I go from the antenna to a bank of HDHomeruns in a room directly below the antenna - very short run. When I run the antenna directly to one of the tuners I get EXACTLY the same signal as running through the amplified splitter.

fstr
9-Oct-2012, 4:59 PM
[QUOTE=teleview;32701]As a test , install the antenna above the roof and run a coax from the antenna to the Tv with no antenna amplifier , couplers or splitters.

What is reception like now??

Is Am radio and FM radio effected also??

QUOTE]

I wish I had a place to install the antenna outside but I just don't.
I have no idea about FM/AM as I do not own any radio to test with

fstr
9-Oct-2012, 7:34 PM
Just to follow up on another question - my garage door is on 315mhz

GroundUrMast
10-Oct-2012, 12:14 AM
On the LAN side of the HDHR's, is any segment wireless?

I ask because our new microwave oven leaks enough RF to shut down all wireless communications in the 2.4 GHz band (802.11b, g & n). You may not have a leaky microwave oven but your neighbor might.

I connect my HDHR's and the HTPC/PVR to the LAN via wired connections only. I can use the laptop for viewing TV via wireless, but i don't depend on it for recordings.

fstr
10-Oct-2012, 1:47 AM
On the LAN side of the HDHR's, is any segment wireless?

I ask because our new microwave oven leaks enough RF to shut down all wireless communications in the 2.4 GHz band (802.11b, g & n). You may not have a leaky microwave oven but your neighbor might.

I connect my HDHR's and the HTPC/PVR to the LAN via wired connections only. I can use the laptop for viewing TV via wireless, but i don't depend on it for recordings.

I run a full wired setup: PC connects to router in living rm, from router I run cat6 to switch in study, HDHomeruns connect up with switch.

fstr
10-Oct-2012, 1:55 AM
I may be on to something though; I installed an app on my phone today that shows signal strength for the HDHomeruns and monitored it every now and again. At some point I noticed poor signal and walked around the house. I found the basement recessed lights on so I turned it off. Instantaneous perfect signal! So I turned it on again. After 2-3minutes the signal dropped. Turn it off. Back to perfect. I have not run conclusive tests (e.g. watching live TV) but it seems to be part or all of the problem.
When we moved in I noticed a weird buzzing sound in one of the recessed lights. I unscrewed the bulb with the idea of replacing the fixture later but have never gotten around to it. Not sure what is causing the buzzing and don't care - I'm yanking that crap out this weekend!

GroundUrMast
10-Oct-2012, 2:43 AM
What type bulb is in the light fixture? Incandescent, CFL, LED or Low Voltage Halogen?

Newer recess cans usually have a thermal overload... if it gets hot it may not switch open with absolute 'toggle' from on to off. I've observed several that simply start to open and the result is arcing across the internal contact of the overload. Some older lamp sockets are simply corroded which results in arcing.

A common cause of overheating is use of a bulb with to high wattage rating. Another is insulation too close to the fixture, trapping heat.

CFL bulbs are notoriously noisy in an RF sense. Some of the new LED bulbs are as well.

fstr
10-Oct-2012, 3:04 AM
What type bulb is in the light fixture? Incandescent, CFL, LED or Low Voltage Halogen?

Newer recess cans usually have a thermal overload... if it gets hot it may not switch open with absolute 'toggle' from on to off. I've observed several that simple start to open and the result is arcing across the internal contact of the overload. Some older lamp sockets are simply corroded which results in arcing.

A common cause of overheating is use of a bulb with to high wattage rating. Another is insulation too close to the fixture, trapping heat.

CFL bulbs are notoriously noisy in an RF sense. Some of the new LED bulbs are as well.

There is no bulb in it - I removed it when I noticed the buzzing originally. Not sure why it is buzzing because it does not do anything special - just a regular 65w housing. Regardless - I'll just replace it as it is cheap