Serving the St. Louis region and beyond.
  • July 31, 2014

Troubleshooting Your TV Signal Reception

Following is some information which we hope will assist viewers having reception issues.

Antenna Positioning
A vast majority of reception issues are due to antenna position.  A common misconception is that the Nine Network’s tower and studios are located in downtown St. Louis. Our transmitter location is located in southern St. Louis County, just west of Highway 21 and north of the Meramec River. Visit http://www.dtv.gov/maps/ to determine the best antenna position and the quality of signal that can be expected at your location. Pictured below is an example of a location in St. Charles in relation to KETC’s transmitter.  Also, since the St. Louis television station transmitters are not all located in the same area, viewers may receive varying reception levels for different stations depending on their antenna position.

Make sure that you antenna is pointed in the correct direction before performing a channel scan on your television or converter box. If your television or converter box doesn’t detect the signal(s) you are interested in you will need to readjust your antenna and perform another channel scan and repeat until the tuner identifies the signal(s).
Once the signal is identified then fine tune the position with the television’s signal strength indicator.

Quality/Strength Indicator

With digital television, viewers will see the same quality of picture regardless of the signal level on their television.  Due to the all or nothing nature of digital reception also known as the digital cliff, it is very important to find and use the signal quality/strength indicator available on the television or converter.  This is a valuable aid for adjusting any antenna to provide adequate signal reception and level to counteract any changes in weather or surroundings that may affect the reception quality over a period of time.

Pictured is the signal strength display normally located in the menu section of the television. Always watch this display when adjusting your antenna. Adjust your antennas to get a steady and strong level.

Indoor vs. Outdoor Antennas
Indoor antennas can be a significant challenge.  While an indoor antenna may work in some locations, an outdoor antenna placement will always work better.  Indoor antennas suffer greatly from effects of ‘multipath.’  Multipath is caused by one or many significant signal(s) reflected from nearby object(s) arriving at the antenna out of time with the main signal.  In digital television it can obliterate signals enough so that the television cannot decode the data.  ‘Dynamic multipath’ is moving multipath which will result in the signal strength indicator moving up and down.  This can be caused by airplanes, cars and people.

Types of Antennas
Common loop and rabbit ear antenna. This is a low cost no gain antenna that may work well for some channels and not at all for other channels. Positioning the antenna near a window that is in the direction of the television broadcast antennas and high in the room may help with reception issues.

This is an indoor log-periodic dipole array antenna sold under various names. If an indoor antenna is necessary this type will normally provide acceptable performance provided the antenna is positioned correctly.

Below is an outdoor yagi style antenna. This antenna will provide good results for outdoor locations and attic installations. This style is also available with additional elements for locations that require higher gain.

For all antennas, especially outdoor antennas make sure that the elements are not bent, broken or touching.

Cable Connections
It is a good idea to check all antenna cable connections to ensure they are tight and in good condition. Screw style F connectors should be used for all connections. Slip on connectors should be avoided unless absolutely necessary.

Screw style F connectors

Passive antenna (RF) splitters will reduce the signal from the antenna. Unnecessary passive (RF) splitters should be removed. Pictured below is a 4 way passive RF splitter. All outputs should either be in use or terminated.

Active splitters are available that do not reduce the signal strength going through it.
Amplifiers may cause problems since they amplify noise as well as signal. Areas close to the broadcast antennas rarely need an amplifier.

Additional Information
http://www.fcc.gov/guides/converter-boxes-and-digital-televisions-troubleshooting

http://www.dtv.gov/fixreception.html

http://www.antennaweb.org/aw/welcome.aspx