50 ohm cable to 75 ohm cable?

Status
Not open for further replies.

wphm449

Member
Joined
Jun 25, 2010
Messages
31
Location
Temecula, CA
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

Member
Joined
Dec 4, 2006
Messages
2,145
Location
Oklahoma
... 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

Completely Banned for the Greater Good
Banned
Joined
Jan 29, 2006
Messages
7,452
Location
Illinois
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

Member
Joined
Jun 25, 2010
Messages
31
Location
Temecula, CA
@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

Completely Banned for the Greater Good
Banned
Joined
Jan 29, 2006
Messages
7,452
Location
Illinois
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
 
Status
Not open for further replies.
Top