50 ohm cable to 75 ohm cable?

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wphm449

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Here's what I want to accomplish to use a roof-mount antenna with my Pro-163 scanner:

-First, I have a 50' RG8/U cable that I will run from the antenna down to my house.
-Next what I want to do is use an adapter to convert RG8/U (with type N connectors) to RG6, then use the existing RG6 cabling in my house to terminate the cable to where I want the scanner to go.
-From the RG6 termination, I will connect a cable to the outlet (on the other end is RG59 or BNC, which will connect to the scanner).

What will the impedence mismatch do to the signal from the antenna to the scanner?
 

LtDoc

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... 75 / 50 = 1.5:1 SWR, if all is done as you said, and, if the antenna is 50 ohms to start with. With a little 'fudge factor', call it about 2:1 or less maybe.
- 'Doc
 

gewecke

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It would be much more efficient to use RG6 "quad shield" from the antenna all the way down to your scanner. :)
Don't worry about the mismatch because you're not transmitting,only receiving.


73,
n9zas
 

wphm449

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@Gewecke

So, if I am only recieving 25-1200 MHz, an adapter between the two cables will work. There will be minimal signal loss?
 

gewecke

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If possible,don't use any adapters at all for the most signal from the antenna. But an adapter to join to lengths of cable together is ok, as long as you don't stack more than one. Ex; RG to F- connectors,RG to BNC,etc. Also better to stay with the same size,rather than mix cable types.



73,
n9zas
 
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