DB8 ANTENNA receiving signal from back of antenna

Rodwalls · 10-Oct-2011, 3:15 PM

Hey All,
I have a DB8 antenna that picks up signal better when the back of the antenna is facing the direction of the towers, I can turn it around so the Bow-ties are facing tower direction and it will not pick up hardly at all. Is there some kind of screwy thing I am doing? Thought I would ask the questions.
Thanks Rod

Tower Guy · 10-Oct-2011, 4:10 PM

Quote:

Originally Posted by Rodwalls

Hey All,
I have a DB8 antenna that picks up signal better when the back of the antenna is facing the direction of the towers, I can turn it around so the Bow-ties are facing tower direction and it will not pick up hardly at all. Is there some kind of screwy thing I am doing? Thought I would ask the questions.
Thanks Rod

If you have a preamp, that's a symptom of overload.

ADTech · 10-Oct-2011, 4:55 PM

It's also a symptom of VHF reception with a DB8.

John Candle · 10-Oct-2011, 7:36 PM

http://forum.tvfool.com/showthread.p...1834#post11834 , http://forum.tvfool.com/showthread.php?t=2164

GroundUrMast · 10-Oct-2011, 8:18 PM

Comparing this post your earlier post, have you removed the second DB-8 and abandon the attempts to combine two DB-8 antennas into one coax?

It would help us if you could describe the entire system starting at the antenna(s), working step by step to the TV(s).

Which stations are received poorly with the antenna facing the towers? Please use the call sign and real channel number, virtual channel numbers are not relevant to the antenna system components.

John Candle · 10-Oct-2011, 8:18 PM

Have you done what I recommended be for?? Is Separate coax going from each antenna?? Are A/B antenna switches being used?? Are the antennas pointed in the directions I have recommended?? Are any amplifiers being used?? By call sign , what are the tv stations that are working or not working with the front and back side of the antenna??

Rodwalls · 11-Oct-2011, 4:17 PM

Here is my current setup. I have one DB8 antenna ran into a RCA Preamp, then into the house. I have the antenna pointing towards Winston Salem-My closest set of channels.

http://www.tvfool.com/?option=com_wr...14f364a61605e6

GroundUrMast · 11-Oct-2011, 10:23 PM

Quote:

Originally Posted by Rodwalls

Here is my current setup. I have one DB8 antenna ran into a RCA Preamp, then into the house. I have the antenna pointing towards Winston Salem-My closest set of channels.

http://www.tvfool.com/?option=com_wr...14f364a61605e6

What happens when you completely remove the preamp and its power supply from the system? The signals from WXII and WUNL are extremely powerful and I would expect the amplifier to be overloaded by those local signals.

Tower Guy · 12-Oct-2011, 1:19 PM

Quote:

Originally Posted by Rodwalls

I have one DB8 antenna ran into a RCA Preamp, then into the house.

I am not aware of any preamp that will handle the signal levels of -11 dbm and -12.2 dbm from WXII and WUNL without overloading. An overloaded preamp prevents the reception of weaker signals.

In order to use the preamp, the signals on channels 31 and 32 must be reduced prior to the preamp. The front to back of the DB-8 antenna will help, but a better solution is to mount the two DB-8s side by side with a spacing of 48". That exact distance will further null the stations from 288° while simultaneously increasing the signal level from 140°.

http://www.hdtvprimer.com/ANTENNAS/ganging.html

You'll want a rotator or a second antenna for 31 & 32.