Question about "N" Type Connectors

[Highlander_821]

I do realize that some people have a different approach to the hobby than I do---I'm pretty casual about it. I want stuff to work like it is supposed to, but I don't sweat a little compromise here and there that more "serious" hams wouldn't countenance. I'm also Scottish, so that means cheap. (Copper wire was invented by two scotsmen fighting over a penny.)

So there is every reason to use N over instead of UHF connectors if every last little DB is important to you. Weak signal work? By all means go with N. Take pride in engineering your station to the highest practical standards? Definitely go with N. Any bands higher than 70cm? Definitely go with type N.

 

[Captain Kilowatt]

Ironic isn't it that what we call UHF series connectors ,the PL-259 and SO-239, are not really that good at actual UHF frequencies. :blink: I guess it goes back to the day when 50 MHz was considered UHF.

 

[Marconi]

That analysis is interesting, and I certainly don't understand whatall the figures mean.

But it seems like, for my scenario with the 440 band, I might be looking at a loss of about 1 DB by going with PL-259 over type N. For my purposes, that doesn't seem like anything to lose sleep over. If 3 DB amounts to 1/2 of an S-unit, then what does 1 DB equate to--1/8 of an S-unit? Oh boy.

821, I'm not sure, but in considering the results in this report maybe we might have to consider that we have several of these connectors in our setup. Allowing for this factor alone we might experience some compounding effects in a real world installation.

I think this report measured and compared single pairs or combinations of a male and female and a barrell connector in order to represent a complete system or unit. So, maybe the loss noted with UHF connectors does not represent what we might experience in our real world setups where we might use multiples of such units.

If I run my feed line direct to my radio I will have two of the devices tested and if I add an inline SWR meter, a switch box, or one or two amps, the number of units and losses really starts to add up.

At 400 mkz I think the report noted as one unit showing 6 watts of reflection with 25 watts of input. Would you reconsider your claim, if your 440 rig was connected using 4 or more of these units as tested in the report?

I don't understand everything in the report either, but just looking at the pictures doesn't always tell the whole story and for sure if we try to relate the results noted to our own real world experiences.

 

[W5LZ]

Very basically, that analysis says that there are losses associated with UHF connectors because of they're not being a constant impedance. Where the 'N' connectors are a constant 50 ohm impedance so don't have those particular losses. I figure that 'loss' thing is going to be fairly standard for any UHF connector, so it sort of boils down to how much 'blood' you wanna squeeze out of that 'stone'. I certainly don't plan to bleed to death, but I ain't too worried about a few scratches, you know? Which is important because -I- said it! Which is about as important as UHF/'N' connectors at HF, sort of...
- 'Doc


... I think I've had too much coffee...

 

[SR385]

Exactly.

UHF Connectors

The man who wrote this is not just a ham, he's an expert in SHF RF design and antenna system design. He used to design and build and sell amps for amateur use and I believe antennas too. Now he's a consultant in the commercial SHF RF market.

Definitely not a weekend reader of the antenna handbook ;-).

I believe he said one night during his Sunday night tech net on the LIMARC repeater that it had been 30yrs since he made an amateur contact below 50MHz.

The net has been on the air 28yrs and is archived and indexed here.

amtv

 

[bob85]

interesting read 385

 

[mackmobile43]

I do realize that some people have a different approach to the hobby than I do---I'm pretty casual about it. I want stuff to work like it is supposed to, but I don't sweat a little compromise here and there that more "serious" hams wouldn't countenance. I'm also Scottish, so that means cheap. (Copper wire was invented by two scotsmen fighting over a penny.)

So there is every reason to use N over instead of UHF connectors if every last little DB is important to you. Weak signal work? By all means go with N. Take pride in engineering your station to the highest practical standards? Definitely go with N. Any bands higher than 70cm? Definitely go with type N.

Hahaha, never heard that one before, very funny

 

[Shockwave]

A few things ..

SO239 is designed for working up to 300 Mhz Only
Even if one is looking for low loss on 144 mhz then SO239 should not be used..

Also N connectors follow the military standard MIL-C-39012 and is designed for use up to 20Ghz..
But N connectors also are designed to keep their quality with many connect and re connections.Type N uses an internal gasket to seal out the environment(giving it better weatherbility).
Also N works better for Very High power levels.

Will N connectors work better on 27 Mhz..
Yes..However they can cost quite a bit more and are harder to assemble .

For 11 meters/27Mhz i would Not worry about using N connectors unless you plan on using extreme power (and then only maybe)

If however you do go to use N connectors..
Then so too you likely would be using far better coax
(like Heliax or at Very Least LMR600 or better)
I happen to use Heliax LDF5-50A with N connectors ( for HF )
But my N connectors are $175 a piece ( a bit excessive indeed)

N type connectors do not handle more power then the Teflon insulated UHF types. This is because of the skin effect and how it relates to the surface area of the center pins in these connectors. The center pin in the N type is much smaller then the UHF and will burn off with too much RF current.

 

[KingCobra_CDX882]

I was simply going by what the specs say and suggest for power handling

regardless...
for 11 meters one should not be using more then 4 watts ( ok 12 on ssb ) LOL

 

[C2]

Which specs were you looking at?