[LJJM]

Hi all,


I am hoping someone here can help me. I live in the Atlanta, GA area and have had my HDTV setup running for close to a year here. I am now having problems with audio dropouts and freeze framing.


These problems have just started and the occur on all digital OTA channels. There is not a set time cycle, but they seem to be increasing in frequency and consistency.


They have just built a new phone switching station right behind my home and my ant. is aimed over the building. The frequency of the problems seemed to coincide with the operation of this facility.


Does anyone have an idea if any of the equipment that the phone company has running in their station may be causing my problems or should I take my DTC100 in to have it checked out???


Any help would be appreciated.


LJJM

 

[Dave McRoy]

LJJM,


Do you see any antennas that look like they might be transmitting antennas on the roof of the structure?


I'd be surprised if the gear within the switching station were emitting enough RFI to get into your antenna, but who knows. I assume you've tried reorienting your antenna?


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HiDefDave


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[dagman]

It would probably help to find out more about that facility. If it is a cell phone station, perhaps you are getting a bit of "groundwave" effect?? But if it is just a landline switching station, I wouldn't think there would be that much RF emmited. Do you have access to a spectrum analyzer?

 

[LJJM]

There are no antennas on top of the building and it is a landline facility and unfortunately I don't have access to a spectrum analyzer. I have noticed that certain appliances in my house cause similar problems... i.e. the buzzer on the clothes dryer and the microwave.


I have tried reorienting my antenna, but by doing so, I loose CBS so that really isn't an option.


Before the switching station was up and running, the dropouts were pretty few and far between and never on FOX, but now it is on every station.


Is there possibly any further shielding that I could do with my coax cable to help prevent this if it is in fact RF interference?


Thanks for you input....


LJJM


[This message has been edited by LJJM (edited 05-16-2001).]


[This message has been edited by LJJM (edited 05-16-2001).]

 

[Impala Bob]

Just for kicks, turn on your AM radio and see if it gets interference at the same time the TV freaks out. If it does you could contact the FCC and get them to check it out. I have a friend that had similar problems and called the power company. They sent someone out immeadiatly and checked for bad insulators on their line. Several were found within blocks of his house. Once replaced the interference went away.


Impala Bob http://www.avsforum.com/ubb/biggrin.gif

 

[larry stern]

I have had a similar problem that I have not resolved (I live in Houston). I have had intermittent, but frequent, severe pixilation on OTA digital channels. In between I get perfect reception but when the problem occurs, all digital channels are simultaneously affected. Of importance, my signal strength as measured by my Hughes 86 HD STB is 100 on all channels at all times and does not fluctuate (during both times of perfect and disturbed reception). I have a replacement Hughes STB "on order" although I am not sure the problem resides with my receiver. Any thoughts?? Thanks, L Stern

 

[J.P.Heff]

I have the same problem.I'm using the DTC-100 and am wondering if it can't lock on. I receive CBS @ 94 and

NBC @ 72 strength but the last couple of weeks constant break-up. My e-mails to the stations have gone unanswered

and I have tried re-positioning antenna but no luck. Is the

new summer foilage on the tree's a possible culprit? I wish the receivers were better dealing with multi-path. Maybe the new Zenith will be. I'm trying new CM antenna/preamp this weekend,so will see how that goes.

LJJM you are not alone...Last night I was so irratated with signal loss on HDTV I was beside myself. Good Luck!!




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JPH

 

[Dave McRoy]

I was getting interference from arcing taking place within a metal conduit feeding power to a neon sign on a restaurant about 200 ft. from my antenna. This type of impulse noise radio frequency interference (RFI) is the same as that which you would experience from and arcing power line insultor and primarily affects relatively low-frequencies, say, from DC up to the highband VHF TV frequencies. Really severe impulse noise RFI can affect lower UHF TV channels, too.


Impulse noise RFI can be located, as previously stated, with a portable AM radio tuned to an unused frequency (that's how I located the source in my situation.) If you tune to an analog VHF TV station (preferably a lowband V like WSB-TV, channel 2 in Atlanta) and see lots of little whit and black specs rolloing up the screen, that's what impulse noise looks like on analog TV. If it's severe enough, and if a digital TV signal that you're trying to get is weak enough it can cause the DTV signal to dropout.


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HiDefDave


STOP HDCP!

 

[Dave McRoy]

JP Heff,


Take a look at your analog TV pictures for signs of ghosting. If you have bad ghosting on NTSC you may experience ATSC reception problems caused by the same multipath interference that causes ghosting on NTSC.


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HiDefDave


STOP HDCP!

 

[J.P.Heff]

HiDefDave,

Thanks for suggestion. I have done that from time to time

and do experience ghosting as some stations are fairly close. Added a RS 0-20 anttenuator which seemed to help some. Will keep trying.Thanks.


John


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JPH

 

[larry stern]

Dave,

Thanks for your input. I want to mention again that when I experience drop outs on all digital stations, my signal strength on all stations is 100.

I also have experienced on analogue VHF channels 2 and 8 in Houston variable white dots (actually larger than dots) that move upward across the screen.

As per your suggestions, I will get a AM portable radio to test for RFI. Do I do this outside near my antenna location? Also, are there any RFI filters that connect to RG6 coax cable?

Larry Stern