[KTrout]

Occasionally the video from our OTA HD feed "drops out". The duration varies between one and two seconds normally, and usually the audio (albeit 2.0) doesn't miss a beat during the loss of picture.


I don't believe it's a transmitter problem because the engineer at the station has equipment able to track outputs etc. and they don't see a variation. I know it's not just my equipment as everyone in the area has seen these same symptoms.


Does anyone know of potential sources for these occurrences???


My guess is equipment either receiving the HD source from CBS or transmitting it from Station location to Antenna / Transmitter via microwave may be hic-cupping, almost experiencing a buffer underrun type of situation. But I really have no experience in any of this equipment etc. and am just fishing.


Any suggestions would be appreciated.


Thanks in advance.

 

[Apps1]

Airplanes flying overhead are a main cause for this.

 

[Ratman]

Multipathing is usually the problem. Are you using an indoor antenna?

Attic antenna, roof antenna?

How does your 'signal strength' look (high, low, steady, bouncing)?

How's your 'line of sight' to the x-mitters?

Any obstructions (trees, water towers, hills)?

How far are you from the x-mitters?


Lot's of questions... but all need to be taken into consideration.

 

[KTrout]

Ratman:

Sorry for answer delay, been out of town.


Using indoor RS bowtie, signal strength is pegged at 100 as I live less than 10 miles away from transmitter. On clear day on my roof I could probably see antenna. No obstructions to speak of.

 

[Ratman]

There's a possibility that you may be overdriving the signal. Only way to test would be to buy (borrow?) a 10dB variable attentuator from Radio Shack. This will allow you to adjust the decrease of the received signal.


May work... worth a try! If it doesn't work... return it.

 

[KTrout]

Is it possible that the station's equipment is "overdriving" the signal? Because I know there are a lot of people in the area experiencing this same problem and the received signal strength varies for all of us.


What exactly does "overdriving" mean anyway?

 

[arxaw]

The signal may be too strong, overloading the receiver. This is most common where people live near full power stations. On analog TVs it may show up as tearing of the video.


Take Ratman's advice and install an RF variable attenuator in the coax line. Try different settings to see if it makes a difference.


Last time I was in Rat Shack they had some RF var. attenuators on close out for 50¢ (really).

 

[KTrout]

Tried an attenuator without any success.


On top of that I posted a couple of specific times during the program that the drop outs occurred and had a number of people tell me they happened at the same time. They live approx. 20 to 30 miles from me. And I'm pretty sure their type of receiver differs from mine as well.