Discone ?

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dirtfinder

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I recently purchased a discone antenna and put it aprox. 25 ft. in the air, my Question is that my hand held picks up all (even more somtimes) than my base does with the discone. did I do something wrong when I sat up my antenna? What can I do to receive better reception? I'am using A pro-2096 & pro-96
 
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tonsoffun

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dirtfinder said:
I recently purchased a discone antenna and put it aprox. 25 ft. in the air, my Question is that my hand held picks up all (even more somtimes) than my base does with the discone. did I do something wrong when I sat up my antenna? What can I do to receive better reception?

First, what kind of cable are you using? Your loss could be in the cable itself.
 

Concrete1

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Try the following:
Hook up the handheld to the outside antenna.
Does it's reception drop off too ?? Does the base "improve" with it's back of set antenna, or when using the HT's duck on it??
If yes, there is a problem, most likley in the cable.
If the handheld is fine on the outdoor antenna, it is probably either a problem in the base unit, or just the difference in sensitivity/selectivity between the 2 units.
Generally speaking, a base antenna, high up in the air, fed with even 150ft of the thin coax, should still at least be equal or better at most freqs, to a handheld inside the house with the stock rubber duck.
If the problem is in the coax, it is probably a connector, open or short, rather than the coax itself, for such an extreme difference,( ASSuming you aren't running something like 600 feet :) )
Another possibility if it affects both is that you are very near a high power xmitter, that is overloading or "De-sensing" the radios when hooked up to the outside antenna.
 
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JASII

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Replace the lossy RG-58 and get at least RG-8 or better still 9913 or even better. When the frequecny goes up the more loss from the cable. So the 50 foot run of RG-58 might be great at CB 27 mHz, but at 800 mHz there might be loss rather than gain. Of course the longer the run the more loss.
 

tom_guess

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To check the resistance, on one end connect one point of the VOM to the center conductor and the other to the outside of the shell, if you have no resistance, that connector is is shorted from the center conductor to the ground. If the connector is good, check the center of one end to the center of the other end. You should have very little resistance if not zero. High resistance would be a broken wire.
 

tonsoffun

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dirtfinder said:
I've got RG-58 coax

Thats what I thought. You say it is 25FT up in the air but how more do you have entering the house. Like JASII said, replace it with a better coax. Thats why I ask what kind of coax you are using. RG-58 is a huge loss.
Why don't you go buy some RG-6 since it is not that expensive and you will see a difference right away.
Just to let you know there is alot of good deals on Ebay for LMR-400 which is a really great coax.
I've seen LMR 400 Times Microwave cable 75' w/ N-Male to N-Male for $36.00. Pretty good deal!
I have bought all my LMR-400 cables with connectors from them and are great.
Take care
 
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dirtfinder

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Thanks to all that have helped me out with some very useful tips, I will start on them ASAP, in the mean time keep the helpful tip coming it is always great to get helpful knowledge in areas that I lack.
 

tonsoffun

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dirtfinder said:
Thanks to all that have helped me out with some very useful tips, I will start on them ASAP, in the mean time keep the helpful tip coming it is always great to get helpful knowledge in areas that I lack.

Sure Dirtfinder anytime. Let us know how you make out!
Take care
 

Al42

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tom_guess said:
To check the resistance, on one end connect one point of the VOM to the center conductor and the other to the outside of the shell, if you have no resistance, that connector is is shorted from the center conductor to the ground. If the connector is good, check the center of one end to the center of the other end. You should have very little resistance if not zero. High resistance would be a broken wire.
Pretty much the opposite. From the tip to the shell should be infinite. From tip on one end to tip on the other end should be very low, and from the shell on one end to the shell on the other end should be very low.

This gives you the DC picture - if any of these are off, there's something wrong. If these measurements are ok, it doesn't mean that the cable is good, it just means that there's no DC problem. The cable could still have an RF short (or impedance bump), or have so much loss that it's unusable.

dirtfinder, whether 25 feet or RG58 is usable or not depends on the frequency. Check here - 3db loss is half the signal being lost in the cable - acceptable, but you want it as low as possible. Check RG6 and see what the difference is at the length and frequency in your particular installation. (If you're interested in 800 MHz, forget RG58 - even 10 feet is pretty lossy.)
 

dirtfinder

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Hey thanks for everything. I check with an vom and sure enough my connectors shorted out. I have order LMR-400 this should do the trick. Yes am tring to monitor 800 seeing that the whole state is almost converted over. I have learned alot in the last few days only cause of the help from all the wonder people in the forum. Again Thanks To All
 

JackTV

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Just make sure that if you order LMR 400 make sure you get the right
connectors installed.If your discone has an N connector as your input
get an N and likewise if it has a SO239 connector get a PL259.
Less connectors more signal!!!

Good luck,
Jack
 
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