2 antennas back to back. Downside?

maypo · 25-Sep-2021, 1:45 PM

Getting ready to put up a new but older (assembled and sitting the barn for 2 years) DB8. I am smack dab in the middle (but slightly closer to rochester) between Buffalo and Rochester. I have an old rotor up the roof now with the really old RS antenna and plan to keep the rotor. I am on a hill and get decent reception from both cities when aimed mostly for buffalo(along with a couple Canadian stations). I got to thinking that i could get another DB8 or maybe a DB4 and mount them back to back, would be less "rotoring". I would still keep the rotor to get a little fine tuning on the occasions i need it. Another consideration was deconstructing the second antenna to a degree and remounting the bowties so they were all on the one frame.
Can someone chime in on the downsides of this choice.

rabbit73 · 25-Sep-2021, 5:41 PM

Quote:

Originally Posted by maypo

Getting ready to put up a new but older (assembled and sitting the barn for 2 years) DB8. I am smack dab in the middle (but slightly closer to rochester) between Buffalo and Rochester......I got to thinking that i could get another DB8 or maybe a DB4 and mount them back to back, would be less "rotoring"......Can someone chime in on the downsides of this choice.

Hello, maypo.

How would you combine the two antennas? Or, would you have a switch to select which antenna you want to use?

Please do a signal report for your location. The TVFool reports are no longer very accurate. Here is a sample report from rabbitears.info for Le Roy:
https://www.rabbitears.info/searchma...tudy_id=357787

You can do a report for your location at this site (I use coordinates from Google maps):
https://www.rabbitears.info/searchmap.php

maypo · 27-Sep-2021, 12:05 AM

https://www.rabbitears.info/searchma...tudy_id=358928

I would want it simple and use some sort of combiner/splitter before the amplifier that is in a closet in the house.
I think the DB8 has a combiner of some sort that combine the signals of what is really 2 DB4s.

rabbit73 · 27-Sep-2021, 10:39 PM

Quote:

Originally Posted by maypo

https://www.rabbitears.info/searchma...tudy_id=358928

I would want it simple and use some sort of combiner/splitter before the amplifier that is in a closet in the house.
I think the DB8 has a combiner of some sort that combine the signals of what is really 2 DB4s.

Thank you for the signal report.

It is possible to combine the two antennas with a splitter in reverse, but it doesn't always work. When the same signals reach the combining point they can interfere with each other if they are not in phase (arrive at the same instant). You will just have to try it.

If it doesn't work, you can:
1. Use an A/B switch to select which antenna to use. This might mean you would have to rescan if your TV can't add a channel after scan.
2. Connect the main antenna to the TV antenna input, and connect the other antenna to a separate tuner (like the Mediasonic HW-150 $40.00) with the output of the tuner going to the HDMI input of the TV.

3. Use a Televes Avant X to combine all the channels from both antennas into one coax. This is the most elegant solution, but it isn't simple to set up and is expensive ($400).

maypo · 28-Sep-2021, 12:48 AM

Right now using my old beam type antenna i an getting most of buffalo and rochester and a bit of canada when aimed at buffalo.
Really dont want to run to the bathroom closet and flip the a/b switch.
Really want to avoid constant rescanning.
Dont really want to pay 400 for the amplifier.
So i will hope that splitter arrangement works...
Will it be best to combine in the closet or up closer to the antennas?

rabbit73 · 28-Sep-2021, 1:55 AM

Quote:

Originally Posted by maypo

Right now using my old beam type antenna i an getting most of buffalo and rochester and a bit of canada when aimed at buffalo.
Really dont want to run to the bathroom closet and flip the a/b switch.
Really want to avoid constant rescanning.
Dont really want to pay 400 for the amplifier.
So i will hope that splitter arrangement works...
Will it be best to combine in the closet or up closer to the antennas?

If there is no preamp at the antenna, try it in the closet before the amplifier.

If that doesn't work, your only options left are the converter box connected to antenna B by a TV, or 2 TVs, one for each antenna.

maypo · 2-Oct-2021, 1:58 PM

I probably should have mentioned this before...I am running 4 TVs in the house now with the antenna cable running into a PCT-MA2-4P Amplifier.

rabbit73 · 2-Oct-2021, 9:41 PM

Quote:

Originally Posted by maypo

I probably should have mentioned this before...I am running 4 TVs in the house now with the antenna cable running into a PCT-MA2-4P Amplifier.

Thank you; I think you did in post #3

Quote:

I would want it simple and use some sort of combiner/splitter before the amplifier that is in a closet in the house.

didn't you? But you didn't say then what amp or how many TVs.

maypo · 12-Oct-2021, 1:44 PM

I took a look for the Televes Avant X and in my wanderings found it to be unavailable on amazon. They did however display these...
Televes 560483 combiner preamp...$100
Channel Master CM-0500 JOINtenna TV Antenna Combiner $20
Im sure the downside of these is similar to what you have posted regarding interference due to possible out of phase signals/and no adjustments to the filtering.
Do these work better than reversing through a splitter?

Tower Guy · 12-Oct-2021, 7:57 PM

The Channel Master combiner isn’t much different than a splitter.

The Televes is much more than a combiner. It’s a dual preamp device each with adjustable gain and automatic gain control, and with anti interference filters. Note that there are four different models.
Look here and download the data sheet.
https://www.televes.com/us/560483-ki...pply-unit.html