Db-8

[signmastr]

http://www.tvfool.com/?option=com_wr...2c157a4eaf092e

I have a DB8 and a Antenna craft Y5713 aimed 147 and 180 as recommended here with a RCA TVPRAMP1R preamp on one 18' mast. My signal levels vary wildly, going from 100% to zero in seconds.
Recent 65mph Santa Ana winds turned my antennas mast. I re-aimed and scanned. I'm now receiving several LA UHF stations. Is it normal for the DB-8 to receive stations from its backside? I have not modified it in any way. Could this cause signal issues with my San Diego stations?

[GroundUrMast]

The newer DB8E specs https://www.antennasdirect.com/cmss_files/attachmentlibrary/Technical%20Data%20PDF%27s/DB8E-TDS.pdf show three lobes off the back side (see page 2 of 9) that could easily provide usable reception and/or pick up interference depending on the circumstance. Virtually all directional antennas will exhibit a pattern like this, though each will be unique in the number of lobes and relative gain.

I don't have the older DB8 specs, but would expect to see a similar ability to receive from the rear. I know of no directional antenna that can claim to block all reception from the rear. They simply concentrate the majority of their reception ability to the front.

[signmastr]

Thank you.
Do some antennas do a better job (maybe the 91xg) of rejecting the unwanted signals? I'd like the option when the time comes to replace the DB8.

[ADTech]

Yes, some do better than others. You have to do some homework in order to implement, though. You have to know the offending frequencies & directions and how they correspond with the lobes and nulls of the antenna under consideration. That's where polar plots show up as most useful.

We've never created a formal Tech Data Sheet for the DB8 since it was our intention to discontinue it when the DB8e became available. Somehow, the DB8 just won't go away...