Quick antenna question

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hawkeye32

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I just recently got a scantenna and am trying to find roughly 75 feet of either LM400 or 9913 coax, now my question is, i am mainly using this for Mil/air freq and trunk systems, thou the AFB i want to lock into is roughly 40 miles (mainly flat surface over water) Will i need a amp as well or can i just run straight shot from the antenna to scanner, also does the LMR400 or 9913 have the proper connections already to plug into the scantenna and my scanner (BC898t) or will i ahve to buy those seperately and crimp them on?? Any ideas would be great, thanks
chris
 

hawkeye32

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I also have a thread up in the wanted to buy section looking for this coax,Also i do live in canada
 

fineshot1

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LMR400 is a good choice. Whether or not it comes with connectors(and what type) on the ends depends on who your purchasing it from. It is also a semi-rigid cable so connecting it directly to your scanner is not a good idea. Usually a short jumper is used for that to keep the strain off the scanners connector. As to whether you will need a preamp is anyones guess as you will first have to try it without to know for sure. There are too may variables to be able to tell you the answer to that.

EDIT: If you put connectors on yourself for LMR400 crimp connectors are the way to go. LMR400 is not well suited to having connectors soldered to it as heat can distort the inner structure of the cable and that can compramise the impedance(50 ohms).
 
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af5rn

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I seriously doubt that you'll need a pre=amp, but that's going to have a LOT more to do with your antenna and radio (which you tell us nothing about) than your coax. It will also have a great deal to do with the band you are monitoring. VHF of any kind, no problem. 800mhz, well... good luck unless you have a quality antenna.
 

N1BHH

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All a preamp will do is increase any local noise and the noise floor as well as overload your receiver with crud put out by paging transmitters, which are notorious harmonic generators. Imagine trying to listen to 305.2 and you have a paging transmitter within 5-10 miles on 152.6. Just double 152.6 and you are in for problems. Plus the preamp would bring in additional mixing products that happen when two transmitters activate nearly simultaneously. I advise against a preamp, unless you are 100 or more miles out in the boondocks. The preamp has to be researched very carefully anyway, so let the antenna do the work and let the best feed line possible do it's work, too.
 

hawkeye32

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Ok thank you very much, as for the scanner i thought i mentioned it i am sorry , I have a BC898T and it will be a scantenna as for the antenna, i bought the scantenna from a guy here on the website should have it tom, just to clarify, it is the BNC connector that goes to the scanner and the male rf connector that goes to the scanner correct?, and yes it will be a crimp ons i know of the soldering and heat for this type of cable
 
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