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Survivalism & Self Sufficiency Topics => The HAM Radio Board => Amateur Radio How-To's => Topic started by: Smurf Hunter on May 16, 2014, 11:12:34 AM

Title: Is there an advantage to "N" connectors?
Post by: Smurf Hunter on May 16, 2014, 11:12:34 AM
I was cleaning out my garage and came across a really nice 20' length of LMR400 coax with N connectors.  I used it with an 802.11b (wifi) antenna I built many years back.  This was way before wifi at every starbucks and pretty sure we didn't call it "wifi" yet.  I vaguely recall at the time choosing "N" for that project because someone explained they were prefered for the very high 2.4GHz wifi frequencies.

For a new HAM like myself starting out with 2M/VHF, is there any practical upside to "N" connectors, or should I stay with the more common PL259 (forget the female designation)?  Seems most gear has PL259.

Hopefully this isn't like the "AR vs. AK" debate. 

Title: Re: Is there an advantage to "N" connectors?
Post by: Alan Georges on May 16, 2014, 11:24:48 AM
For a new HAM like myself starting out with 2M/VHF, is there any practical upside to "N" connectors, or should I stay with the more common PL259 (forget the female designation)?  Seems most gear has PL259.

According to this paper:
http://www.qsl.net/vk3jeg/pl259tst.html
don't worry about it at 147 MHz, but when you get up to 440, it starts to matter.
Title: Re: Is there an advantage to "N" connectors?
Post by: Carl on May 16, 2014, 04:52:33 PM
There is a bit more strength and a bit less loss,but not enough to use expensive adapters that actually add MORE LOSS .
Title: Re: Is there an advantage to "N" connectors?
Post by: backwoods_engineer on May 23, 2014, 11:01:21 PM
At HF, it doesn't matter.  At VHF and high power levels, and at UHF, the lower return loss (read: SWR) of the N connector over the "UHF" (PL-259/SO-239) connectors makes a difference.

If you want to use N-connector cables, just get hold of some adapters for your rig.  If you use N-connector cables, and you build antennas at VHF/UHF, use N female connectors on the antennas.
Title: Re: Is there an advantage to "N" connectors?
Post by: Carl on May 24, 2014, 05:17:44 AM
At HF, it doesn't matter.  At VHF and high power levels, and at UHF, the lower return loss (read: SWR) of the N connector over the "UHF" (PL-259/SO-239) connectors makes a difference.

If you want to use N-connector cables, just get hold of some adapters for your rig.  If you use N-connector cables, and you build antennas at VHF/UHF, use N female connectors on the antennas.

But does not adding an adapter just put loss and weakness back into your system?
I know the answer...the adapter just negates all advantage of the N connector.

N connectors are stronger,and have less an impedance 'bump' at VHF.

The higher the frequency,the more cables look like plumbing and more
important they are to system efficiency.Check out microwave wave guides...
Title: Re: Is there an advantage to "N" connectors?
Post by: backwoods_engineer on June 12, 2014, 07:22:28 PM
No, not if you get low-loss adapters.  I have personally measured some on my $50,000 network analyzer at work that has less than 0.2 dB of loss. 

You get a 50' piece of LMR-400 and compare that to a 50' piece of crap truck stop RG-58, and you can see as much as 2 dB difference.

Now, Smurf Hunter might not see a difference on his short piece.  But why not use a found piece of good coax, even if you have to cough up $15 for a couple of adapters from Pasternack?
Title: Re: Is there an advantage to "N" connectors?
Post by: Smurf Hunter on June 12, 2014, 11:33:05 PM
No, not if you get low-loss adapters.  I have personally measured some on my $50,000 network analyzer at work that has less than 0.2 dB of loss. 

You get a 50' piece of LMR-400 and compare that to a 50' piece of crap truck stop RG-58, and you can see as much as 2 dB difference.

Now, Smurf Hunter might not see a difference on his short piece.  But why not use a found piece of good coax, even if you have to cough up $15 for a couple of adapters from Pasternack?

I believe this.  After building my copper pipe jpole I started with a 50' length of rg58 from radioschmuck.  Of course I then attempted to tune things.  When I later replaced it with a wuality 18' rg8x with silver soldered ends my SWR meter showed a full watt more on.the forward needle.

This experience alone taught me a lot.
Title: Re: Is there an advantage to "N" connectors?
Post by: Carl on June 13, 2014, 06:15:13 AM
I believe this.  After building my copper pipe jpole I started with a 50' length of rg58 from radioschmuck.  Of course I then attempted to tune things.  When I later replaced it with a wuality 18' rg8x with silver soldered ends my SWR meter showed a full watt more on.the forward needle.

This experience alone taught me a lot.

Shades of KUNG FU....ah brass-popper ,grasp the crystal from my hand and prove worthiness.....

You are learning fast Smurf Hunter! 
Title: Re: Is there an advantage to "N" connectors?
Post by: backwoods_engineer on June 15, 2014, 05:12:43 PM
Shades of KUNG FU....ah brass-popper ,grasp the crystal from my hand and prove worthiness.....

You are learning fast Smurf Hunter!

Indeed!  Smurf Hunter is coming along fast in our hobby!  Welcome, SH!  We are going to have to exchange callsigns by PM sometime once you get operational on HF.  I hear your neck of the woods on 20m on PSK31 all the time.