Connecting a Decibel antenna to Uniden 396XT

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Hi everyone,

I was given a free antenna and I was looking to use for my Uniden 396XT. I would like to know what I would need exactly to make this antenna work on y 396XT.

The antenna that I have is a Decibel DB493-A 806-866MHz range.

Thanks for the help!
 

jaspence

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Antenna

A better description of the antenna would help. Many of us might not be familiar with that model. The first thing is what kind of connector does it use and does it have coax already attached. If it has coax, what type of connector is at the radio end? If you are in a simulcast area, you may find that it works worse than the 396 antenna due to signal path distortion.
 

n5ims

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Nothing special about the installation, just a typical base station antenna connected to a portable scanner. Since it's a portable scanner, you'll need to make sure you don't stress the antenna connector on the radio, which thick, stiff coax will quickly do. A brief jumper using a short run of thin, flexible coax is a very good idea to reduce this stress and save your radio from damage to the antenna connector.

* You'll need a mast to mount the antenna (nothing special here, any typical antenna mast will work, some galvanized electrical conduit, or even a piece of standard PVC pipe if you don't care about a long life).

* You'll need some coax to reach between your antenna and your scanner. Since this is an 800 MHz antenna I guess you'll be using it on that band (it won't work very well on much below 700 MHz so that should be a good guess), you'll need some quality coax that is very low loss at that high of a frequency. At the very least, some quality RG-6 (wrong impedance, but should work if length isn't too long), better to use some LMR-400 or even better, lower loss coax if you can.

* Proper connectors for your situation. The antenna uses N connectors so you'll need a male N for that end. The scanner includes an SMA to BNC adapter so you can have a male BNC on the scanner end. Another idea would be to have a short jumper that has the SMA on one end to mate with your scanner (verify it's the correct version since there are several) and on the other end has a female N connector to mate with one of those pre-made coax cables with an N male on each end to go between the scanner and antenna.

* If the antenna is mounted outside, you'll need to also worry about grounding, but since there are literally hundreds of threads on that topic, I won't go into detail on that part, just search a bit and follow the advice from the better posts on that topic.

One comment that's important. Your antenna is highly directional so you'll need to point it at the system's tower to hear them. Don't expect to pick up more than one or two systems unless you have a rotator on the antenna so you can aim it at the various systems you want to listen to (and scanning more than those in direct line won't be possible).
 

teufler

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you need coax from Amazon,they have 10-30 feet for coax with a N connector and a sma connector on the other end.SMA is what goes on the 396xt. Beam has a 59 deg beam width so that will be pretty convenient in that you can point at a tower, 30 degrees eith side of the exact heading and you will not notice a big difference in signal strength. If you mount outside, drill a samall hom,e and attach a wire to the mast, then attach wire to a pipe driven into the ground. This is just a safety deal. Small protection to a lighting strike. If you have higher object around where the antenna is mounted , probably not necessary. A direct hit on the antenna, if connected to the radio, the radio will be shot. LMR 400 or heavy coax technically is better but for a short run, 30 or less, The small coax like rg8x would work. The flexibility on the connector against the no flexibility of heavy coax wopuld be more desirable. If the 800 mhz towers are less than 10 miles from your house, the added gain will not be noticeable..
 

marksmith

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Your scanner has an SMA connection.

Depending on your location and what you can receive in 800mz without the base anyenna, you may not find it a big help, especially because of the directional aspect, unless you are going after one specific system.

Mark
536/436/WS1095/HP1/HP2/996T/996XT/996P2/396XT/325P2/PSR800/15X/others
 
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