Best way to combine 2 high band vhf antennas

well it depends on what you're trying to accomplish

If you have one antenna mainly for one station and the other one for the rest then a jointenna is what you need. As example I have one antenna for Minneapolis (9, 11) and the other for a distant VHF the opposite way (12)....I would get a jointenna for 12 which blocks 12 on the Minneapolis antenna and picks up the other one

Now if you have more than one station on each one then I really dont know ;)
 
I'm wanting to stack a set of vhf high bands to improve gain.
I switched a high band antenna craft for a winegard,and now I get Baton Rouge.It's weak,but steady.
Since I have 2 antennacraft's,I figured I could stack those and maybe come out ahead.
I'm still working on uhf from the same area.I get channel 33 great,but don't get 44 very often,which apparently comes off the same tower,only thier broadcast antenna is lower on the lower.Maybe even a lower power is what it seems. It's not consistant like the 33 signal--which has always been a strong signal in this area,even on analog
 
Use 2 equal length pieces of coax, one from each antenna, identical balums on each antenna, and a splitter in reverse. It is important for the balums to be in phase or the signal will not add together properly. i.e. if you do not get good results, reverse the connection of one of the balums. Also important is the spacing between the 2 antennas.
Check here for a good discussion on combining antennas
Stacking, Ganging, Combining TV Antennas - Digital Forum
 
The folks over at Digital Home are real freaks when it come squeezing out that last bit of signal. Read the topic that Larry posted and then look for the one on baluns. Just going with a quality balun like a Channel Master could get you an extra db or two depending on the channel and what you are using now.

Here is the thread and on page 44 there is a nice chart of loss comparisons.

Baluns (Brands, Designs, Losses, DIY Loops, etc.) - Page 44 - Digital Forum
 
After the storm in July destroy most of my VHF antenna I when out and brought two Channel master CM 1111 VHF antennas which I will stack next spring using a Winegard CC-7870. Was going to do it this year but after my mother pasted away in September and then a delay in getting a new metal roof installed until next week ever thing got put on hold. The biggest issue will be the channels that your after and the amount of spacing that will be need for the channels your after. If you haven't already since these here's a couple of links that you might find interesting.

Winegard - Vertical Antenna Stacking: In-Depth
Combining or Stacking Two TV Antennas - Stallions Satellite and Antenna
 
If you really want to test your sanity Winegard had a 300 ohm combiner to avoid some balun loss. Its probably still available but I read somewhere that you had to twist the equal length 300 ohm lines a matching number of times while having matched standoff distances from the pole.
 
This is an example of where two heads are not better than one. Phasing two antennas is not for the impatient.

On the other hand, it may make for some serious multipath rejection.
 
well it depends on what you're trying to accomplish

If you have one antenna mainly for one station and the other one for the rest then a jointenna is what you need. As example I have one antenna for Minneapolis (9, 11) and the other for a distant VHF the opposite way (12)....I would get a jointenna for 12 which blocks 12 on the Minneapolis antenna and picks up the other one

Now if you have more than one station on each one then I really dont know ;)

I have a situation where I need to pickup 2 VHF stations 162 degrees apart (a moderate channel 10 @ 183 degrees and a weak channel 13 @ 021 degrees) I also need to pickup multiple, strong UHF stations @ 90 degrees.

I assumed 2 yagi for the VHF (1 moderate, the second deep fringe) and a simple UHF.

These all will be in an attic that is NOT used for storage. It is a 3 family and will serve as a master antenna for all 3 apartments (first floor will need an amp near the antennas to compensate for the long run, the 2nd and 3rd floors will be much shorter runs)

Any help would be appreciated.

Rick
 
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I have a situation where I need to pickup 2 VHF stations 162 degrees apart (a moderate channel 10 @ 183 degrees and a weak channel 13 @ 021 degrees) I also need to pickup multiple, strong UHF stations @ 90 degrees.

I assumed 2 yagi for the VHF (1 moderate, the second deep fringe) and a simple UHF.

These all will be in an attic that is NOT used for storage. It is a 3 family and will serve as a master antenna for all 3 apartments (first floor will need an amp near the antennas to compensate for the long run, the 2nd and 3rd floors will be much shorter runs)

Any help would be appreciated.

Rick

Post a link to your RabbitEars Signal Search Map result.


- Trip
 
I assumed 2 yagi for the VHF (1 moderate, the second deep fringe) and a simple UHF.
Assuming the UHF antenna is at 90 deg to the VHF antennas, I think that should work. You could use one of those UHF/VHF splitters (in reverse) to combine the UHF with the other two to prevent any leakage from the VHF stations into the signal coming down the coax.

The VHF antennas should also do what you want assuming they have big honking reflectors at the rear. You don't want the medium strength signal entering the VHF antenna pointed the other direction and interfering with itself.
 
I would suggest that you custom build your own diplexer for channels 10 and 13 using coax stubs. To do so you would need about 23' of RG-6 coax, 6 F connectors and three type F tee connectors.

N/C (OPEN) CH 10 ant OUT CH 13 ant N/C

___________________________________________________T____________________T___________________T___________________________________________________

RG-6 125.0" 11.4" 12.4" 113.6"'

The 125" length is 2 3/4 wavelengths on channel 13 and 2 1/2 wavelengths on channel 10, therefore it passes channel 10 and nulls channel 13.
The 113.6" length is 2 1/2 wavelengths on channel 13 and 2 1/4 wavelengths on channel 10, therefore it passes channel 13 and nulls channel 10.

The extra lengths between the stubs allows both signals to reach the output connector.
Note that this drawing may not look right on a smart phone. If it is confusing, try it on a computer.

K2TR
 
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Post a link to your RabbitEars Signal Search Map result.


- Trip

For channel 13, I plan on using

https://www.newark.com/stellar-labs/30-2476/deep-fringe-directional-antenna/dp/71Y5462

For Channel 10


For the UHF that are very stong, I have a Gray Hoverman that I made a few years ago that works great for the UHF
 
I would suggest that you custom build your own diplexer for channels 10 and 13 using coax stubs. To do so you would need about 23' of RG-6 coax, 6 F connectors and three type F tee connectors.

N/C (OPEN) CH 10 ant OUT CH 13 ant N/C

___________________________________________________T____________________T___________________T___________________________________________________

RG-6 125.0" 11.4" 12.4" 113.6"'

The 125" length is 2 3/4 wavelengths on channel 13 and 2 1/2 wavelengths on channel 10, therefore it passes channel 10 and nulls channel 13.
The 113.6" length is 2 1/2 wavelengths on channel 13 and 2 1/4 wavelengths on channel 10, therefore it passes channel 13 and nulls channel 10.

The extra lengths between the stubs allows both signals to reach the output connector.
Note that this drawing may not look right on a smart phone. If it is confusing, try it on a computer.

K2TR
Tower Guy,

Thank you. I need a little more information to wrap my head around this. Do you know of any links that I could read to fill in the blanks? What gets attached to the 2 open tee's? I assume this will minimize the need to space the 2 VHF antennas so far apart (I had planned around 5').

I have plenty of RG-6 and F connectors, I'll find tee's. I also have an RCA powered VHF/UHF combiner/amplifier, the amplifier is about right for the 3 way splitter loss and the shorter cable runs.

I have a single family cape that I live in. I use an old school antenna (RCA ANT3038E) pointing south and a 4 Director Yagi, tuned to 213 Mhz, that I made pointing 020 degrees and 3' lower. The problem I have is that it sways on windy days. I was thinking of using a chimney mount, A Gray Hoverman pointing East, The Yagi I'm using now on the corner bracket aimed as it is now and a 2 director Yagi, tuned to 195 Mhz on the South side of the chimney. The diplexer you describe, combining the VHF and a VHF/UHF combiner would work much better.

Here is the location map;
The setup I have now, with the 4 director Yagi, has also been able to pull in 11 and 26....on calm days!

Thank you again for your help!

I am a cabinet maker that loves learning.

Rick
 
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There are no unused ports on the T connectors.
Lets start with the channel 10 antenna. It gets connected to the first T, that T is also connected to the 125” stub that passes 10 and nulls 13. The third port of the first T has an 11.4” RG-6 that is connected at a second T. The second T will be the combined output to your preamp.

Now let’s look at the channel 13 antenna. It gets connected to a third T that is also connected to a 113.6” stub that passes 13 and nulls 10. The third port of the third T is connected to 12.4” of RG-6 that is then is connected to the second port of the second T.

There is information on coax stubs here:
K1TTT Technical Reference I wrote the original article for ham radio interference protection. Dave Robins, K1TTT, did the analysis.

As far as I know this specific diplexer design is original, and has not been published.
 
One more observation for your location. Distribution of TV signals works best when all stations have the same strength. Because WTNH is about 20 dB stronger than WGBY, you might try adding 20 dB of attenuation to the channel 10 antenna before the diplexer. Then use your preamp on the diplexer output. To remove your strong UHF signals from the input to the preamp, use a UVSJ as a UHF filter, and then a second UVSJ to combine the preamp output to the UHF antenna.

You have plenty of signal strength on the UHF stations. I doubt that you will need an amplifier for those stations.
K2TR
 
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