Connector Fits

[Angelica231]

Hi all,

When it comes to amateur connectors and their use; I'm good. I've found myself in a new domain with SMA/RP-SMA. The back of my GRE scanner has a BNC connection, no issue. I wish to try an Alpha wifi antenna on the back of the scanner. I have a BNC to RPSMA female (outside thread center pin) and the antenna itself is male with center socket. Will this combination function as a 'standard' antenna connection? With signal being center and shield being ground.

When we speak of reverse polarity, I somehow get the impression the signal is on the shield and the ground path is on center, which will *NOT* work.

I live fairly close to downtown St. Paul and my scanners "almost" do ok without the antennas. This is why I though the Alpha antenna might be worth a try.

My knowledge of the SMA world is extremely limited and I have the feeling I'm trying to back the car into the garage sideways

Angie

 

[a417]

an "Alpha WiFi antenna"?

why are you trying to use an antenna designed for 2.4 ghz on a scanner designed for VHF/UHF? Do you not have a stock antenna to use? Or a piece of random wire with a BNC on it?

This sounds like too many moving pieces, for no good reason.

 

[fxdscon]

Hi all,

When we speak of reverse polarity, I somehow get the impression the signal is on the shield and the ground path is on center, which will *NOT* work.Angie

In the context of RP/SMA connectors, the term "reverse polarity" refers only to the gender of the connector's contact pin, and does not refer to the signal polarity.
.

 

[Angelica231]

Thank You fxdscon! Question answered!

 

[Angelica231]

First - I am only talking about ONE connector, for me not a serious issue and no moving parts.
Secondly - A person has to use what is on hand and what is affordable

 

[popnokick]

Before you use a wifi antenna on the GRE scanner (which is completely mismatched for the freq range), at least try one of these very inexpensive alternatives -
- An indoor-style TV antenna made for top of set or wall mounting (they are very effective for scanner freqs)
- The hookup wire version of this antenna (scroll down the Wiki page to see it)
Homebrewed Off-Center Fed Dipole - The RadioReference Wiki
You'll need an F to BNC adapter for either of the above. Place either antenna as high up in the building as you can, and preferably near a window.

 

[a417]

Secondly - A person has to use what is on hand and what is affordable

There's affordable, and then there's appropriate.

You most likely bought that adaptor, as that's not exactly a junk drawer type thing for most people, and for the price of that adaptor...you could have purchased a loose BNC connector and put a piece of random wire on the end.

"A piece of injection molded plastic over wire does not an all-band antenna make" - i forget who told me that. The amount of improvement you will likely gain with using a horribly mismatched antenna for that frequency will not offset the amount of money you saved with this idea.

It's a good attempt, yes you are not transmitting with it, but you're trying a little too much of a reach