$9 10db yagi

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Ishmole

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Question: I see that the antenna impedance is 50ohm. The scanner uses 75 ohm. I would like to think that using 75 ohm coax for lead in is ok and there is very little, if any loss, if the antenna system is used for receive only and not transmit.
I am going to give it a try. What do you think?
Mike
 

kellykeeton

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Question: I see that the antenna impedance is 50ohm. The scanner uses 75 ohm. I would like to think that using 75 ohm coax for lead in is ok and there is very little, if any loss, if the antenna system is used for receive only and not transmit.
I am going to give it a try. What do you think?
Mike

Not sure where your data comes from. The scanner and antenna spec at 50ohm.
 

kellykeeton

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Has anyone tried this antenna? Reviews?

It's a commercial antenna that is very well built. Not sure what type of review you are looking for. "My trunking system went from 4 bars to 5 bars" or "removed all intermod"

Reviewing an antenna beyond build quality is a little silly - what works for me isn't the same for you in the real world. The manufacture specs the antenna and since it's commercial use there are nice documents with numbers on performance.

When it comes down to it - the review is positive for what the antenna is. For $10 it's a super super awesome recommended review. If you need a directional antenna for 800mhz it's still an amazing deal at the increased $20 price. The aluminum alone is likely worth 2-4$ in scrap price.

I would recommend checkin out the post by mmckenna Previously In this thread where he detailed someone asking "will it work for me"

Hope that helps a little
 

rwilcox1951

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Yes, it helps. Thanks. I realize there's no magic fix to reception problems. I'm on the fringe of an 800 mhz trunked P-25 system. Sometimes I receive loud and clear, other days nothing. I usually receive better with some snow cover on the ground and on clear cold days. I did order the antenna but was just looking for some anecdotal evidence from someone that they noticed a marked improvement. I'm hoping I can use this with another antenna at the same time on a single scanner. Anyone have experience with this? I presume I need to split the signal at the antenna and feed just one coax.
 

mmckenna

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Question: I see that the antenna impedance is 50ohm. The scanner uses 75 ohm. I would like to think that using 75 ohm coax for lead in is ok and there is very little, if any loss, if the antenna system is used for receive only and not transmit.
I am going to give it a try. What do you think?
Mike
You won't have an issue. Even if you were transmitting, you wouldn't notice anything other than maybe a 0.1 or 0.2 increase in the SWR.

Just use good quality cable and connectors. Seal -everything- that is outdoors really well. RG-6 and the like is good cable if you keep the runs short. If you are expecting to run 100 feet of RG-6 at these frequencies, you will be losing most, if not all, your antenna gain to feed line losses. The higher you go in frequency, the more pronounced feed line loss is. You really should be looking at higher grade coax if your run is longer than 20-30 feet. LMR-400 is a good place to start. LMR-600 or 1/2 inch heliax would be a much better solution.
You can crunch the numbers yourself here: Coax Calculator
 

kellykeeton

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Snoqualmie, Wa
I'm hoping I can use this with another antenna at the same time on a single scanner. Anyone have experience with this? I presume I need to split the signal at the antenna and feed just one coax.
just plug them up with a T conenctor. there are some null issues but mostly you dont care. it will work fine.
 

Ishmole

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You won't have an issue. Even if you were transmitting, you wouldn't notice anything other than maybe a 0.1 or 0.2 increase in the SWR.

Just use good quality cable and connectors. Seal -everything- that is outdoors really well. RG-6 and the like is good cable if you keep the runs short. If you are expecting to run 100 feet of RG-6 at these frequencies, you will be losing most, if not all, your antenna gain to feed line losses. The higher you go in frequency, the more pronounced feed line loss is. You really should be looking at higher grade coax if your run is longer than 20-30 feet. LMR-400 is a good place to start. LMR-600 or 1/2 inch heliax would be a much better solution.
You can crunch the numbers yourself here: Coax Calculator
Thank You! I remember reading a while ago, that it did not make a difference.
 

de784

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Delaware
Wirelessly posted (Mozilla/5.0 (Linux; U; Android 4.2.2; en-us; HTC6435LVW 4G Build/JDQ39) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30)

Shipped today.. does anyone have a performance report?
 
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