Reverse polarity connectors. What's the purpose?

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videobruce

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Specifically SMA though I have seen many others.

Questions;
1. First off, what is the purpose of these reverse polarity connectors? Aren't there enough already?
2. Is the RP-SMA the 'common' connector on wireless routers (WiFi)?
3. Why was the name chosen? Isn't it misleading since there is no "reverse polarity" but there is a reverse "gender".

Thanks in advance.
 

zz0468

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Specifically SMA though I have seen many others.

Questions;
1. First off, what is the purpose of these reverse polarity connectors? Aren't there enough already?
The purpose is to make it more difficult for consumers to modify operation that would cause the device to exceed Part 15 emissions rules. By modify, I mean use a larger, higher gain antenna, or adding an amplifier, or some similar act.

2. Is the RP-SMA the 'common' connector on wireless routers (WiFi)?
Reverse TNC's are pretty common, too.

3. Why was the name chosen? Isn't it misleading since there is no "reverse polarity" but there is a reverse "gender".
Semantics... I see a lot of things, particularly naming conventions, related to WiFi devices that doesn't make a whole lot of sense. Add this one to the list.
 

videobruce

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There are antennas that will screw directly into those connectors without any adapter.
That didn't prevent anything.

Really stupid idea.
 

videobruce

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Other than installing the antenna, all that is required is the proper cable.
Not really any different.

If you can install the antenna, the rest is nothing. My point is it was a stupid idea! There are already way too many connectors out there already! :evil:
 

jim202

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Weather you think it is stupid or not, the point is the FCC set limits and the WIFI mfg
companies have tried to comply by using the reverse polarity connectors.

Sure there is a ton of different connectors on the market. I have to pay close attention
to each model part number for any connectors I order. It makes a difference if your
using LMR-400 or RG-8 type cable. There are specific connectors to fit each of these
cables. To the average person, the connectors look the same. To the person trying
to put these connectors onto the cable, you will find out real fast that a crimp LMR-400
will not fit very well on the RG-8 coax cable. You can force it to fit, but it will take
some hard pushing. There is also a difference between RG-8 and RG-9 crimp
connectors. Again you can force fit them, but that's not the correct way.

Jim



Other than installing the antenna, all that is required is the proper cable.
Not really any different.

If you can install the antenna, the rest is nothing. My point is it was a stupid idea! There are already way too many connectors out there already! :evil:
 

jon_k

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That's not what they're trying to prevent. Try replacing the whip antenna with a 4' dish. Or a 10' dish.
If the router has a MALE connector on back -- and your feedline does too, is it not easily solved by a FEMALE-FEMALE barrel converter?

5 minutes at any Fry's or if lucky radio shack will get you what you need.

Honestly, I haven't attempted to modify my access point yet and have not taken note of the antenna connector.
 
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jon_k

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OK.

Seems it's not so simple as a gender changer.

Here is RP-SMA:


The matching normal SMA:


Solution:
Grab a /third/ SMA connector with a pin inside and cut the pin off. Insert the pin in one of your connectors and apply the other connector. Now you've converted one of the connectors into the proper gender to get RF through at 50 ohms without modifying any of your equipment.

Simple fix. Albeit hard for most people to figure out.

I'm not too sure either about the FCC guidelines. I know they say it has to be "hard" to modify the systems to go over power -- but if someone wants to modify it they will find a way. Most will not bother.
 
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SCPD

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jon k i noticed on your discussion, the pictures of the sma connectors it looks like the tv connectors I have on a roll of digital satellite cable rg6..1800 mhz eb2833 18 awg 75 c (ul) type cl2 . I was wondering if this could be used on a discone ant. which is in my attic with an adapter or a connector? the cable i have now has rg 58 and rg 8 to my scanner, i am not familar with cables .tnx
 

jon_k

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jon k i noticed on your discussion, the pictures of the sma connectors it looks like the tv connectors I have on a roll of digital satellite cable rg6..1800 mhz eb2833 18 awg 75 c (ul) type cl2 . I was wondering if this could be used on a discone ant. which is in my attic with an adapter or a connector? the cable i have now has rg 58 and rg 8 to my scanner, i am not familar with cables .tnx
PM sent, since this discussion is somewhat off topic to this post. Will explain full details there and explain the differences.
 
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