Two Discone Antenna's (at same time)

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Saint

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I have two Discone antenna's, could I get better reception if I used a good splitter and ran both Discones at the same time if the were around 10 feet apart.
Steve
 

iMONITOR

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I have two Discone antenna's, could I get better reception if I used a good splitter and ran both Discones at the same time if the were around 10 feet apart.
Steve
I don't think there would be any advantage to doing that. What are you trying to accomplish?

The only time I've seen two antennas connected to one scanner is when they're using two yagi antennas to increase signal levels from two different directions, often 180 degrees apart from each other. Or when you are using one antenna for 850MHz band and another antenna for something like VHF/UHF, 150MHz & 450MHZ. I had done something similar to an 800MHz trunked system and VHF/UHF aircraft, and using a diplexer to couple the two antennas to one coax.
 

Saint

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I don't think there would be any advantage to doing that. What are you trying to accomplish?

The only time I've seen two antennas connected to one scanner is when they're using two yagi antennas to increase signal levels from two different directions, often 180 degrees apart from each other. Or when you are using one antenna for 850MHz band and another antenna for something like VHF/UHF, 150MHz & 450MHZ. I had done something similar to an 800MHz trunked system and VHF/UHF aircraft, and using a diplexer to couple the two antennas to one coax.
Just wondering if I would get better reception on weak signals.
Steve
 

Hit_Factor

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I have two Discone antenna's, could I get better reception if I used a good splitter and ran both Discones at the same time if the were around 10 feet apart.
Steve
You could try it for the cost of a splitter. It won't cause damage.

Antennas might be out of phase, creating a condition similar to simulcast distortion.

For specific weak siganls I might use a preamp, maybe a rotating yagi.
 

Saint

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You could try it for the cost of a splitter. It won't cause damage.

Antennas might be out of phase, creating a condition similar to simulcast distortion.

For specific weak siganls I might use a preamp, maybe a rotating yagi.
Ok thanks for the information take care
Steve
 

wtp

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for reception only , there are no rules, you can try anything, wire, paper clip, wet noodle.
just to see if it helps or hurts in your particular situation.
 

Saint

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for reception only , there are no rules, you can try anything, wire, paper clip, wet noodle.
just to see if it helps or hurts in your particular situation.
Yes I'm thinking about getting a splitter and trying it, just like an antenna it might work for me with my setup and my area of scanning.
Steve
 

wtp

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i had to do the same thing to get over the air TV ch. 11 when they went digital.
two TV antennas pointed is the direction of the tower and a TV/cable splitter used in reverse.
2 antennas into the TV way. and if a car came down the road the station went out. better than a doorbell.
 

mmckenna

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i had to do the same thing to get over the air TV ch. 11 when they went digital.
two TV antennas pointed is the direction of the tower and a TV/cable splitter used in reverse.
2 antennas into the TV way. and if a car came down the road the station went out. better than a doorbell.
Difference is the TV antennas have gain. The discone antennas don't.
Then you add a splitter that will have additional losses.

Like other said, give it a try, but don't expect a miracle.
 
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Saint

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i had to do the same thing to get over the air TV ch. 11 when they went digital.
two TV antennas pointed is the direction of the tower and a TV/cable splitter used in reverse.
2 antennas into the TV way. and if a car came down the road the station went out. better than a doorbell.
There you go, it does not hurt trying something if it wont work OK but if it does work.... happy days.
Steve
 

ko6jw_2

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You need to take into account the insertion loss of a splitter/combiner. I have a very high quality (up to 900MHz) one with an insertion loss of 3.5 DB. Then there is the loss from the impedance mismatch since the splitter is probably 75 Ohms and the antennas are 50 Ohms. Finally these are unity gain antennas so adding unity to unity is still unity. Much better to try to increase the height of the antenna and use the lowest loss coax you can afford.
 

Saint

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You need to take into account the insertion loss of a splitter/combiner. I have a very high quality (up to 900MHz) one with an insertion loss of 3.5 DB. Then there is the loss from the impedance mismatch since the splitter is probably 75 Ohms and the antennas are 50 Ohms. Finally these are unity gain antennas so adding unity to unity is still unity. Much better to try to increase the height of the antenna and use the lowest loss coax you can afford.
OK thanks for this information, I am thinking on changing the coax to a better product. I have rg58 now
Steve
 

iMONITOR

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I have two Discone antenna's, could I get better reception if I used a good splitter and ran both Discones at the same time if the were around 10 feet apart.
Steve
You still haven't told us what band (frequencies) you're monitoring.
 

ko6jw_2

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OK thanks for this information, I am thinking on changing the coax to a better product. I have rg58 now
Steve
Definitely get rid of the RG58. Suggest LMR400 or equivalent. Only use 58 in short mobile installations or for short patch cords.
 

Saint

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Sorry Right across the bands, 108 to 174 MHz and 400 to 1300 MHz, I pick up a lot of frequencies in my area in Canada And United States from my apartment. I thought maybe RG-8 coax might be the way to go for upgrading my coax, only need a 50' foot run from scanner to discone antenna.
Steve
 

dlwtrunked

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I have two Discone antenna's, could I get better reception if I used a good splitter and ran both Discones at the same time if the were around 10 feet apart.
Steve
Unless you place one directly above another, you are just as likely to get worse reception as better reception. In any case, the improvement is marginal--a few dB. I once had a commercially made discone of that sort (may still have it somewhere in my shed).
 

Saint

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Unless you place one directly above another, you are just as likely to get worse reception as better reception. In any case, the improvement is marginal--a few dB. I once had a commercially made discone of that sort (may still have it somewhere in my shed).
I might get better results upgrading my coax cable.
Steve
 

iMONITOR

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Sorry Right across the bands, 108 to 174 MHz and 400 to 1300 MHz, I pick up a lot of frequencies in my area in Canada And United States from my apartment. I thought maybe RG-8 coax might be the way to go for upgrading my coax, only need a 50' foot run from scanner to discone antenna.
Steve
Stick with the discone if your required bandwidth is that wide. Realistically there is no one antenna or even two together that will perform well over that range. What are you monitoring above 800-900 MHz? RG-8 will not perform well, there's too much loss at those frequencies.
 
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