Coax Cable Adapter/Connectors Quality

[WRDJ205]

I have seen many discussions about the importance of low loss cables like LMR400.

Is there a similar rating for coaxial cable adapters?  Are all adapters/connectors equal?  Do I need to order from a specialty company like DX Engineering or would ones from Amazon be suitable?  
 

Thanks!

Geauxfish

[OffRoaderX]

1 minute ago, WRDJ205 said:

 Are all adapters/connectors equal?

if I have learned anything from "some people", it's that if you aren't using $65 connectors, your radio "will work like garbage" ... 

[WRDJ205]

Yup but I would hate to spend $120 for a low loss cable only to lose it all at a cheap connector.  Thinking more along the lines of $5 vs $2 type of comparison.  
 

edit: Clarification $2 vs $20 comparison 

Edited May 15 by WRDJ205

[SteveShannon]

31 minutes ago, WRDJ205 said:

I have seen many discussions about the importance of low loss cables like LMR400.

Is there a similar rating for coaxial cable adapters?  Are all adapters/connectors equal?  Do I need to order from a specialty company like DX Engineering or would ones from Amazon be suitable?  
 

Thanks!

Geauxfish

There are several good quality connectors such as Amphenol, M&P, and DX Engineering. The best are literally silver plated, but unless you string together several of them in a row the advantage probably won’t make a lot of difference. 
But there are some shitty connectors out there also and one of them could cause issues. 
I choose to buy connectors and adapters from companies I have faith in like DX Engineering unless it’s for the junk box.

 

[WRQC527]

12 minutes ago, WRDJ205 said:

I have seen many discussions about the importance of low loss cables like LMR400.

Is there a similar rating for coaxial cable adapters?  Are all adapters/connectors equal?  Do I need to order from a specialty company like DX Engineering or would ones from Amazon be suitable?  
 

Thanks!

Geauxfish

The quality differences I have found have little or nothing to do with performance, it's more about the connectors falling apart when I disconnect them. And since I don"t keep track of the brand or where I got them, (Amazon, Ham Radio Outlet, Ebay and ham swap meets usually), I don't know (or care) which brand is best. I buy what appears to be a good deal, and if they eventually fall apart, they get trashed. It doesn't happen very often. To me, a $9 Amphenol connector is not three times better than a generic $3 Amazon connector. I'm sure there are those who will pontificate otherwise.

 

[WRQI583]

All of my antennas except my HF and 2 meter antennas use "N" connectors at the antenna. The side that plugs into the radio is a PL 259 that I picked up on Ebay because that is what sits on the back of the radio. I have heard that at VHF and UHF frequencies you will lose half of your signal using PL 259 connectors. Well, if that is the case, why do they put an SO-239 on the back of the radio for the PL 259 to plug into? In my experience, if you have good coax and a good properly tuned antenna, you will do fine. You are running under 50 watts or less on GMRS, so the loss is minimal. I had a 45 watt radio with the SO-239 on the back of it in the house at one point on LMR 400 coax running about 60 feet to a  element Yagi with an "N" connector mounted about 32 feet up above the ground. I live in a hole compared to the terrain around me at around 310 feet above sea level. I was able to get into the Mt. Washington (NH) UHF repeater on Ham from my place around 102 miles away in Central Maine with a decently strong signal. With that type of setup, the only thing that stops my signals are hills, and even then, I have used hills to bounce or bend my signals in different directions.

[BoxCar]

The cheap connectors have inferior dielectric between the poles as well as poorer grades of metal. The dielectric won't handle high power (KW range) as well and the center pin can more easily shift causing impedance problems if they are moved frequently. For the most part, if you use one and it stays in place there will be very little, if any, difference in the overall performance of your radio.

[WRYZ926]

18 minutes ago, BoxCar said:

The cheap connectors have inferior dielectric between the poles as well as poorer grades of metal. The dielectric won't handle high power (KW range) as well and the center pin can more easily shift causing impedance problems if they are moved frequently. For the most part, if you use one and it stays in place there will be very little, if any, difference in the overall performance of your radio.

This is true and also why some of the cheap connectors from Amazon, eBay, etc, do not work as well nor last as long.

That being said, I have not noticed any differences between the Amphenol connectors and those from DX Engineering or  Max Gain when testing the cables and antenna SWR.

[Lscott]

On 5/14/2024 at 11:00 PM, WRQC527 said:

To me, a $9 Amphenol connector is not three times better than a generic $3 Amazon connector. I'm sure there are those who will pontificate otherwise.

You get what you pay for, and sometimes not even that.

I’ve gotten in to the habit of checking SMA connectors by screwing different types together. The cheap ones seem to have poorly cut screw threads on the SMA ends. If the connectors screw together completely, seats and doesn’t exhibit ANY hint of binding it’s useable. Otherwise it’s junk. I’ll spend some time digging through the vendor’s bins at a swap checking every SMA connector I want to buy before dropping my money on them. I’ve been burned before and have a handful of bad ones to prove it. At $4 to $5 each it adds up.

[WRKC935]

I guess the important question here is why would you be looking for adapters instead of the correct connectors for the application to begin with?

Yes, there are different levels of quality and pricing with RF connectors.  The stuff for microwave test beds and maintenance that are made from stainless steel and come with little charts with the attenuation factors for the frequency range the connector is good for can cost you as much as you spent for your whole antenna system for a single Male SMA to Female N adapter (paid 200 bucks for one)  it had a like expectancy before it would go out of spec of 100 insertions.

Do you need those for GMRS, NO.

But on the other end of it, I have bought the cheap Amazon stuff and had the nut's fall off the PL259 and N type connectors on their first use. 

That's adapter stuff.  But connectors are the same way.

If you are going to be using LMR series cable, make the investment in the crimping tool for LMR 400 (and 600 if you plan on working with it) and use the Times Microwave connectors that are designed for that cable. LMR braid doesn't solder well at all.  Leaving you with the choices of crimp or compression type connectors.  The connectors are captive pin if you get the EZ style connectors which makes using them EZ.  There are people that will tell you that captive pin is junk and you have to solder center pins.  Personal experience from over 14 years of using them says otherwise.  I have NEVER had a failure of a connector  that was correctly installed to begin with fail in the field.  And remember that the connector behind the radio isn't the one that goes bad, it's the one that's in the air connecting the antenna to the coax that you need to be worried about.  Because that's the hard one to get to. 

Yes, the connectors are 20 to 30 bucks a piece, but if you avoid needing to climb your tower or take your pole down to access the failed connector in a year, it's cheaper labor wise to use the better stuff.

 

[WRDJ205]

32 minutes ago, WRKC935 said:

 

I guess the important question here is why would you be looking for adapters instead of the correct connectors for the application to begin with?

 

It’s surprising how often I need an adapter of some kind.  Mobile antenna or power meter to HT comes to mind.  

[Lscott]

1 hour ago, WRKC935 said:

guess the important question here is why would you be looking for adapters instead of the correct connectors for the application to begin

One example. The antenna installation on my CX-5 the mount with cable was only was available with an SMA connector on the end. There was another one, with the mini RG8X cable connector on the end, but it was too short to make it from the roof rack mount to inside of the rear hatch. I wanted to go to some mini RG8X cable, as an extention, that only had RG8X connectors. All I had on hand was SMA to BNC. Had to use the higher loss RG-58 extension cable until I can buy the adapters I want at the Dayton Hamvention this weekend.

 

[Socalgmrs]

I’ve got a 20w radio with 40’ of Lmr400 hooked to a 9db antenna.  My n type to 259 connector on the back of my radio costs $5.  My radio transmits over 200 miles. Sooo it works even if I lost some wattage.     If you have a good radio and a good antenna and low Loss cable does 1 connector really matter?   Probably not.  Just don’t buy the cheapest stuff you can.  I use marine grade water proof shrink wrap on all my connections that are out doors.