Configuring two antenna into CM Amp

[bob.gibson@att.net]

I have two digital antennas pointed in different directions and would like to converge both signals through a Channel Master CM-3412 2-port signal amplifier and into my DVR. I'm just not sure what coaxes go where. I have the power going into the amp at "PWR IN, 12-16 VDC", a coax going from the amp to the DVR "RF OUT, 11 dB", and the two antenna coaxes entering into the amp at "PWR IN, RF OUT 11dB" and "RF IN, REV OUT, 4dB". The signals appear to be fine, but is it configured correctly? Do I possibly require a 4-pole amp?

[ADTech]

The amp has only a single input for antenna signals, it cannot properly combine two antennas except by pure accident.

The four ports labeled as outputs are that, outputs. One of them is configured to allow the amp to be remotely powered (see directions) but that is not an input for an antenna.

[rabbit73]

Bob:

Sorry you are having trouble.

My instructions were obviously not good enough to make it clear what you needed to do. Also, your second thread asking about the CM 3412 should have been added to your original thread so that ADTech would know what you were trying to do. You didn't tell him what two antennas you were trying to combine.

What two antennas, by brand and model number, are you trying to combine?

Your original thread:
Help with antenna selection and possible options in San Diego
http://forum.tvfool.com/showthread.php?t=15686

http://www.tvfool.com/?option=com_wr...8e03afb14308f1

Originally Posted by rabbit73

A splitter can be used in reverse as a combiner, but it doesn't always work because when the same signals arrive at the combiner they will interfere with each other if they are not in phase. In your case you should combine two antennas, one for VHF and one for UHF with a UVSJ, which is a low loss device that combines the two bands without interference.

The signal loss in an attic is difficult to predict because of differences in construction. A metal roof, aluminum thermal barrier, aluminum siding, and stucco will block signals, as will trees and other buildings.

For KFMB CBS on real channel 8 and KGTV ABC on real channel 10 install a Winegard HD7694P aimed at 230 degrees magnetic. The 7694 is a VHF/UHF combo antenna because VHF-High only antennas are now in short supply.

For KSWB, down thru KNSD, install an Antennas Direct DB4E aimed at 144 degrees magnetic.

I have selected antennas that will give a little extra gain because your 2Edge signals might have a hard time making it over the terrain obstructions. You can see the terrain profiles if you click on callsigns in your TVFOOL report.

You probably will not need a preamp, but if you run out of signal after splitting, you can replace the splitter with a distribution amp like the Channel Master 3412 or 3414.

If that doesn't work, you can move the distribution amp to the attic and remotely power it through the coax or install a preamp.

A UVSJ is designed to combine a UHF antenna with a VHF antenna so that they don't interfere with each other.
http://www.solidsignal.com/pview.asp?p=uvsj
http://mjsales.net/products/tru-spec...ant=1198505857
http://www.radioshack.com/vhf-uhf-go...r/1502586.html

DB4e >
      \
       UVSJ > coax > splitter > TVs
      /
7694 >

If you need more signal for two sets, replace the splitter with a CM 3412 which is an amp an splitter combined in one unit:

DB4e >
      \
       UVSJ > coax > CM 3412 > TVs
      /
7694 >

[bob.gibson@att.net]

My apologies. I really appreciate the help!

I purchased two antennas - the Winegard HD7694P (aimed at 230 deg. magnetic) and the Antennas Direct DB4E (aimed at 144 deg. magnetic) as you specified in your original reply to me. I have a Tablo DVR so I wanted both signals to be directed into the DVR, then Wi-Fi from the Tablo to my router, then, finally, to my Roku device. It worked like a champ and I am able to see several channels at very high resolution!

In your original reply, you mentioned as an option to purchase the Channel Master CM 3412 (or CM 3414). I went ahead and purchased the CM 3412, but I'm not certain how to configure the two incoming coax signals into the CM 3412. In addition, I'm not sure what port on the CM 3412 is used to output the signal to my Tablo DVR.

[rabbit73]

I purchased two antennas - the Winegard HD7694P (aimed at 230 deg. magnetic) and the Antennas Direct DB4E (aimed at 144 deg. magnetic) as you specified in your original reply to me.....It worked like a champ and I am able to see several channels at very high resolution!

Good.

In your original reply, you mentioned as an option to purchase the Channel Master CM 3412 (or CM 3414). I went ahead and purchased the CM 3412, but I'm not certain how to configure the two incoming coax signals into the CM 3412.

The two coax lines from the two antennas DO NOT go into the CM 3412. The two coax lines go into the UVSJ to combine the signals into one coax line that goes to the splitter.

BUT

I looked at your previous thread and I see that I misunderstood what you were saying. You never said that you were going to split the signal. The only time you mentioned splitter was

He felt that no amplifier was necessary and that I could couple the two coax lines from the antennas into a splitter and send it down one line and into my office.

I have a Tablo DVR so I wanted both signals to be directed into the DVR, then Wi-Fi from the Tablo to my router, then, finally, to my Roku device.

If the combined signals from the UVSJ go directly into the DVR, then you don't NEED a splitter in the first place. My fault for misleading you, and I apologize. Mea culpa.

DB4e >
      \
       UVSJ > coax > DVR > 
      /
7694 >

If the signals from the attic loss are weaker than expected, then add a CM3410 or 3412 between the UVSJ and the DVR:

DB4e >
      \
       UVSJ > coax > CM3410/12 > DVR > 
      /
7694 >

If the 3412 is near the DVR, then its power supply can be nearby. If the 3412 in in the attic to amplify the signals before they come down the coax, then it can be remotely powered up through the same coax that feeds the signals down.