How to tune scanner antenna with cb swr meter??

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katclaw

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Hi guys. I order a radioshack magnetic scanner roof antenna and I need to tune it, but the swr meter I have is for cb radios. So this scanner antenna has the same conections (bnc) as a cb radio antenna? Or I need an adapter to be able to plug the scanner antenna to the swr meter ? Or there are specific scanner antenna tuners?
All this is for my uniden bc346xt
Thxz
 

RDGDigital

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Okay, let me start off by saying I am by no means an export on radios to say the least. But my understanding of SWR meters is that they measure how much of the TRANSMIT signal is sent out through the antenna and how much is reflected back into the radio as heat. One of the main reasons for measuring SWR is that if too much signal (heat) is reflected back into the radio it could cause circuits to burn out. And since a scanner does not transmit there is nothing to measure.

That's the extent of what I know. Maybe someone else can provide a better explanation.
 

jaspence

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Tune cb antenna

A SWR meter is used to tune an antenna for transmit. There are other devices that will indicate if an antenna is resonant in the desired frequency range, but they are considerably more expensive than a simple swr meter. They do not require a separate transmitter to test the antenna.
 

tech020

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Go to eBay, they have chinese "antenna analyzers" that cover up to 1,000Mhz. The one I bought is about $100 and works well for ham frequencies. These have microtransmitters built in to measure VSWR and do not cause interference. What you will find is that most multi-band scanner antennas are not all that good. A simple quarter wave whip at a given freq will work as well or better.
 

k3cfc

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Scanner antenna

Hi guys. I order a radioshack magnetic scanner roof antenna and I need to tune it, but the swr meter I have is for cb radios. So this scanner antenna has the same conections (bnc) as a cb radio antenna? Or I need an adapter to be able to plug the scanner antenna to the swr meter ? Or there are specific scanner antenna tuners?
All this is for my uniden bc346xt
Thxz
There is no need to tune a scanner antenna.
 

ko6jw_2

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First of all, some RS mag mount scanner antennas could transmit on 2m and 440. The problem with these antennas is that they were not made to be tuned. They should be just fine out of the box for scanning. If you want to tune or check an antenna without transmitting, then you need an antenna analyzer. I have one, but they are quite expensive and in the case of a RS scanner antenna you may not want to know what's happening. Remember, tuning of a receive only antenna which is designed to be broadband will not help the performance. It may degrade it. If you need maximum performance on a specific band, get an antenna made for that band.
 

katclaw

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ok thank you very much. So I will just plug and play !

I don't need fancy antenna analizers or something like that yet, is my first scanner so I will just play with it and see what happen.
Thank you again for answer me.
 

Ed_Seedhouse

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As has already been posted you don't need to worry about tuning a scanner antenna. In fact this is generally true for any antenna that will be used only for receive, except possibly a magnetic loop, which will come with it's own "tuner" anyway.

When you start to transmit a good match is important. But modern receivers are so sensitive that even an antenna way of tune for a given frequency will still work just fine.
 

wtp

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Port Charlotte FL
no rules on receive

you can try anything to receive. try tv antennas,paperclips,soda cans,rg 6cable stripped back and the center conductor in the air. experiment and have fun. i just tried a broken (got it that way) cb antenna for use on 800 mhz. it was a little better than leaving the scanner on the seat. someone had parked in a bad area and the antenna was cut at about 2 inches. their loss my gain. so see what works for you. also those cable/tv line spliters work in reverse so two antennas to one radio is possible.
 
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