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eHam Forums => Elmers => Topic started by: N4BAM on July 05, 2013, 04:31:21 PM



Title: RF Connectors
Post by: N4BAM on July 05, 2013, 04:31:21 PM
Which is better or is there a difference between crimped and soldered (besides the obvious)?  I'm using DXE-400 MAX coax cable.  Thanks in advance.


Title: RE: RF Connectors
Post by: N3HFS on July 05, 2013, 04:38:37 PM
Which is better or is there a difference between crimped and soldered...?
Soldered connections will generally give better electrical/RF performance.  But there is a trade-off...if a soldered connection is not properly done, a simpler (but still correctly done) crimp connector might easily outperform it.


Title: RE: RF Connectors
Post by: KC9NVP on July 05, 2013, 06:08:49 PM
To me it depends on how good you are at soldering.  I generally solder all of my RF connectors (certified solder at work for thru-hole and SMT) and I have the proper soldering iron and gun at home to handle the larger connectors and to get on/off quickly.  If you are not good at soldering, then crimping may be the route for you or find some one who is good at soldering to do it for you.

73, David


Title: RE: RF Connectors
Post by: K8AXW on July 05, 2013, 08:17:40 PM
There is a learned talent for doing both connections as well as the correct equipment.

I know in our power department, tens of thousands of crimp connectors are not only the norm but soldered connections are strictly forbidden.

In the RF business, most prefer soldered connections.  However, if you have the correct tool and take the time to learn to do a crimp connection properly....and are able to tell a bad connection from a good one.... then you won't have any problem with the crimp connections.

Personally, I prefer the soldered connection and have never had one fail in 57 years. 


Title: RE: RF Connectors
Post by: W8JX on July 05, 2013, 09:10:42 PM
Which is better or is there a difference between crimped and soldered...?
Soldered connections will generally give better electrical/RF performance.  But there is a trade-off...if a soldered connection is not properly done, a simpler (but still correctly done) crimp connector might easily outperform it.

A good crimp connector is superior to solder when properly installed with proper tools. Plus, they are far more consistent in mass production.


Title: RE: RF Connectors
Post by: N3HFS on July 05, 2013, 09:22:30 PM
Soldered connections will generally give better electrical/RF performance.  But there is a trade-off...if a soldered connection is not properly done, a simpler (but still correctly done) crimp connector might easily outperform it.
A good crimp connector is superior to solder when properly installed with proper tools. Plus, they are far more consistent in mass production.

omg...controversy!   ;D  But it's all good. No worries about either method as long as it is done properly.

p.s., I also like the superior mechanical connection of properly soldered coax terminations.


Title: RE: RF Connectors
Post by: AF6WL on July 05, 2013, 09:34:14 PM
Solder connections to the braid are prone to fracture making crimp connections along with their strain relief boot more reliable.
Another less common option is the clamp type connector - available for many cables.
These are probably even more reliable than both solder and crimp connectors if a lot of flex is expected.


Title: RE: RF Connectors
Post by: AD6KA on July 05, 2013, 10:52:31 PM
I have always soldered all my own RF connectors,
and, while it's not one of my favorite tasks, I am
fairly good at it.

But I have read some posts here from people whose
opinions I value, that crimped RF connections can be just as good,
if not better, IF done properly with high quality tools.

So, just for s***s & giggles:
If I were to buy all tools I need to do an
*outstanding job* of crimping RF connectors:

1) How much would I have to spend in total (approx) to acquire said tools?

2) What are some "highly rated but not wayyy overpriced" brands
     of these tools? (Yeah, I realize you get what you pay for!)  ;D

3) Can I buy the crimper & dies *just* for the type
    of coax and connectors I need,
or do I have to buy
     the "whole kit & kaboodle" Set?


FWIW: %99 of my work is with PL-259's, using
RG-213 (or eq w/stranded center conductor) and
RG-8X jumpers for around the shack or short
low power HF runs.

Thanks in advance for your advice!
Hope you all had a happy and safe holiday!
73, Ken  AD6KA


Title: RE: RF Connectors
Post by: AC5UP on July 06, 2013, 06:09:01 AM
I've worked with and around a fair amount of connectors in a commercial environment and when you see something like a TV station built with a pantload of BNC's that are 100% crimped, you have to wonder.......... Is it cost efficiency, reliability, or signal quality that made the decision?

Hands down it's convenience and cost efficiency because using a soldering iron behind a poorly lit rack is not the hot tip for a textbook perfect connection. But, as for signal quality, I've seen plenty of 20+ year old crimped cables that work as good as new. Which is another form of cost efficiency. Downtime is money lost and re-cabling doesn't come cheap so if there were reliability issues with crimped connectors you wouldn't see them at the big money operators. When you realize how demanding an RGB (Triax) video system is on signal balance you stop worrying about how good a crimped connection might be because if anything would test the value of a cable, that's it. Seeing a good signal on one cable is a good thing but it's quite another to manage three in parallel that are matched for impedance, loss and length.

Let's just say it is possible to do a bad crimp job just like it's possible to do a bad solder job, but in my experience a bad solder job is more likely. Especially if you do connectors only occasionally.

Note to AD6KA: Yeah, you can buy the crimper frame alone then add the dies you need. You will pay more per piece as compared to a bundled kit, but avoid buying something you may never use. So the consideration is between thrift and convenience. Buy the kit and you're covered both now and in the future. Maybe.

Some crimpers have a combo die like this: http://www.molex.com/molex/products/family?key=coax_crimp_tool&channel=products&pageTitle=Introduction&parentKey=rf_microwave_coax_connectors
Others use one die per connector size: http://www.amphenolconnex.com/rf-coaxial-crimp-tooling-selection-guide

I think the Molex option looks about right for the typical Ham / hobbyist situation..............................


Title: RE: RF Connectors
Post by: G3RZP on July 06, 2013, 06:20:32 AM
I've found that crimped BNCs on laboratory leads tend  to give up where the braid enters the ferrule.  They get a lot of bending and twisting in use, and it usually takes 6 months in a busy lab. Soldered  and correctly fitted BNCs seem to last longer. But we are talking here about a somewhat specialised and rough application.


Title: RE: RF Connectors
Post by: W8JX on July 06, 2013, 08:33:27 AM
Soldered connections will generally give better electrical/RF performance.  But there is a trade-off...if a soldered connection is not properly done, a simpler (but still correctly done) crimp connector might easily outperform it.
A good crimp connector is superior to solder when properly installed with proper tools. Plus, they are far more consistent in mass production.

omg...controversy!   ;D  But it's all good. No worries about either method as long as it is done properly.

p.s., I also like the superior mechanical connection of properly soldered coax terminations.

In years past I did a lot of mil spec cabling bad patch panels with all types of coax. Crimp was preferred method for consistency and no heat damage to dielectric and a strong connection too.


Title: RE: RF Connectors
Post by: N4BAM on July 06, 2013, 10:54:48 AM
Thanks for all the advice, I appreciate the help!


Title: RE: RF Connectors
Post by: WB6BYU on July 06, 2013, 07:39:26 PM
Crimp handles vibration in aircraft better than soldered.  The local installer I talked with
wouldn't use anything else. 

They are particularly useful when putting a new connector on a mobile cable that won't
quite reach out from under the seat - I certainly would rather not try to solder in such
a position.

We use expensive jumper cables at work:  5' cables with SMA connectors at each end
for somewhere around $200 each.  (A shift of 0.3dB can cost us thousands of dollars
a day.)  They are all crimped, though even at that price we still add a few layers of
hot glue heatshrink tubing to reinforce the cable at the connectors.


Crimp equipment doesn't need to be expensive.  This crimper kit from Marlin P. Jones
looks like it handles all the common cable types:

http://www.mpja.com/CRIMP-TOOL-H_D-4-PART-DIE/productinfo/5770%20TL/

I have a very similar tool that I got for twice the price from Mouser:

http://www.mouser.com/catalog/specsheets/EPD-200400.pdf

and found that just one of the dies works for most of the connectors I commonly use.
Think I changed it out once when I needed a different size.  It includes a stripper that
prepares the coax in one pass.  I still have a supply of solder and clamp-type connectors
on hand, but find that I use the crimp type first if I have the right type on hand.


Title: RE: RF Connectors
Post by: N6AJR on July 06, 2013, 08:21:10 PM
I used to solder everything, but I broke down and got the Kit for crimping ( http://www.hamcq.com/ ) and now I crimp everything.  I also keep out on the look for deals on connectors.  I recently go 122 n connectors  for lmr 400 ( I have about 2000 feet of it , another "deal" ) from Italy for $145 shipped, which works out to about a buck a piece for silver N connectors.  and yes , the crimp seem stronger.


Title: RE: RF Connectors
Post by: K2YO on July 07, 2013, 08:24:44 AM
1) How much would I have to spend in total (approx) to acquire said tools?

2) What are some "highly rated but not wayyy overpriced" brands
     of these tools? (Yeah, I realize you get what you pay for!)  ;D

Take a look here;
http://www.qsradio.com/Connectors.htm

I've done business with them and they have done right by me.

Regarding high cost; when you start talking mil spec connections, the crimpers get really expensive. For example a real molex crimper costs a whole lot more than the after market crimper.  You will have to make a decision for yourself if its work paying for the mil spec crimper.

For me, I'm ok with the lower cost crimpers as long as they work.



Title: RE: RF Connectors
Post by: N6AJR on July 07, 2013, 12:06:34 PM
yup, my crimper set, with cutters, strippers and crimper handle handles  for several different sizes were like $95 for the set.  not cheap, but not prohibitively expensive.


Title: RE: RF Connectors
Post by: K6AER on July 09, 2013, 03:16:48 PM
In the cell phone industry we have been using crimp or mechnical connectors for over 30 years. Typical cell will have close to 36-40 connectors. There are close to 2 million cells on the air. That is s lot of connectors.


Title: RE: RF Connectors
Post by: G3RZP on July 10, 2013, 02:44:59 AM
They don't get a lot of connects and disconnects, though, do they? Connectors that sit there connected most of their life tend to be pretty reliable, and for that sort of application, crimping is definitely the way to go.


Title: RE: RF Connectors
Post by: K5LXP on July 10, 2013, 06:04:57 AM
You'll be a believer in crimps the first time you have to install a connector at the top of a tower.  Even under general field conditions, crimp is just plain more convenient.  Not as likely to accidently melt a hole in the carpet of your car installing that mobile, either.

Mark K5LXP
Albuquerque, NM


Title: RE: RF Connectors
Post by: K2YO on July 10, 2013, 06:21:15 AM
Mil spec connections are all crimp not solder. So that probably says something about reliability.



Title: RE: RF Connectors
Post by: G3RZP on July 10, 2013, 06:48:33 AM
I go along with crimp with the exception of the lab jumper leads. We'd buy the jumper leads with crimped BNC connectors and nice plastic supporting boots, but they would only last about 6 months with the constant connecting and disconnecting. Same with the sub-vis and SMA - they all broke the braid where it exited the crimp. Solder on BNCs would last about 9 months......but could be quickly repaired without needing the crimping tool - which, inevitably, had been 'borrowed' by another department, and nobody knew which one!

Precision N connectors, according to one manufacturer, are really only good as 'precision N' for about 300 mating cycles. Not sure if there isn't a similar limitation on some other precision connectors.