Once upon a BNC ...

Skill loss and new types of connector invented. Brian

For mass-produced/industrial work crimped connections are more reliable than soldered. While you (and I maybe) can produce reliable D-I-Y soldered connections, en-masse they are statistically less good than crimped ones. I doubt there are very many D-I-Y BNC users now and so the market simply isn't there for soldered ones.

Wrong supplier? :-)

Farnell, RS, CPC, or

Avpx

Yup, wrong supplier chosen - though I do think the times have truly changed, if these have dropped out of the "mainstream". I'm pretty sure even Maplin would have stocked them.

You video monitor is more likely to be connected HDMI these days rather than 75 ohm bnc.

I don't like that type of crimp connector either but did manage buy a batch of solder jobbies from eBay a while back.

Cheers, T i m

Whenever you put your telly on you're watching signals that have travelled through scores of crimped BNC connectors in studios and OB trucks. These days , with uncompressed serial digital video running at 3 Gb/s.

In 37 years working in the industry, I've only ever known a couple to fail in service. And probably less than 20 or so to be a 'duffer' when made.

"solder bucket BNC" still gets results from RS, Farnell etc

I've sent plenty fail in use or when made but that could be down to the wrong technique, poor tools or cheap components (or a mix of each).

When I installed an Thin Ethernet LAL at one my jobs I used solder / bolt up RG58 BNC connectors throughout and never had one of those fail either. In contrast with the crimp RG58/9's I've tried though, I never had one fail whilst being made.

And the bolt up seem so much neater, no strands of screen wire sticking out and as a benefit, the solder / bolt up and re-useable. ;-)

Quite a few times I've 'nicked' a connector from one of my cable to make another.

It seems wrong to try to make a crimp BNC, learn it's faulty when tested or intermittent in use to just cut it off and throw (all that engineering) away. ;-(

A mate offered me a handful of RG59 BNC's to make up some CCTV cables and even though I have a reasonable crimping tool, the crimp connectors being much cheaper and more readily available, I politely declined his offer.

Mind you, I have benefited from bad crimps as he gave me what he thought was bad CCTV camera that turned out to be just a bad (crimped) connector. ;-)

Cheers, T i m

I could say you could have looked harder in your search :-)

This is one of the first hits in a search for a BNC 75 ohm connector

YMMV

Yes RS have them silver plated if you like as well, Lots of bits in a likkle bag and not cheap. I never had much luck with bnc for anything more precise than video, the locking part would get loose and some of them wobbled even when locked. Scope probes seemed to be the worst. However then everyone went over to the screw in types but of course then you had a big hassle if you needed to change the lead. I don't think I know of a super reliable quick connect and release socket system. Brian

Stretching the 'split' socket I'm guessing?

Quite, even when they were too short and caused network instabilities (as I saw in person on a mates Co network).

The only time I managed to pull a solder / bolt up BNC connector off a (RG58) cable was when trying to extract a cable from behind a very heavy equipment cabinet and I had to pull *very* hard. Even after that, I was able to recover the pin and the connector and re-unite them on a new cable. ;-)

Maybe it's because I'm reasonably adept at soldering and mechanics that with my extra glasses on and sufficient practice (knowing the lengths of the different sections) I can make a 100% reliable / predictable BNC connection where even if it seems to go perfectly, I don't really trust crimps?

After 5+ years of fairly regular use and millions of movements, one of the wires broke off the connector on the extruder stepper motor on my

The extruder goes left and right ~200 mm (and up/down 150mm but slower) and this cable came directly off the fine JST plug, over the top frame of the printer and down to the controller and was completely unsupported, meaning all the load generated by this constant left / right movement was managed by the wire in the connector.

When replacing it, I noticed it was something I must have soldered up

Cheers, T i m

I doubt any of the plug in connectors inside your computer are soldered. They will all be crimped.

In the broadcasting industry every cable is bespoke, and hand made. Pre-made crap and/or components from China etc is not permitted.

I worked on one project where the chief engineer insisted that return loss was measured on every cable, and the parameter monitored for 3 minutes per cable to ensure stability !

He had a lot of time on his hands !

Yes, 'now', but that certainly wasn't always the way (and I'm talking in general now) and do you think they are now 'always better' for being crimped, or simply that they may be quicker for the manufacturer to make?

I believe there are some instances were crimping is supposed to be better than soldering but that isn't because of the actual connection in most cases but the environment (heat and / or movement of a cable near a soldered connection etc).

It's also possible that the crimping process is easier to mechanise but again, that's nothing to do with the final quality of the solution (when both are done optimally).

As an aside, when I was racing RC cars, some drivers would *solder* the battery wires into (and out of) their cars because *any* connector (itself soldered or crimped) would potentially add both resistance and unreliability. I did solder the speed controller directly to the motor but used (soldered) 30A Anderson Powerpole connectors on the battery (with a captive 'O' ring keeping the two together). Never ever had any of them fail in use.

However, the whole soldering (or not) issue doesn't really cover things where the density means that it's not easy (and so reliable) to solder by hand, and especially where re high density IDC (rather than crimp) connections are concerned.

You are less likely to find a bad connection where the crimp has been made onto the insulation than with a connection that was designed to cut through it.

Maybe if I was making up BNC connectors all day and had access to the best components and tools available I'd use crimped ... but I think I'd be looking hard for another job (having had to make 'batches' of cables over my career) ... ;-)

Cheers, T i m

I think they are called IDC, not soldered and not really crimpted, it amazes me that this type of connector is so realible.

Ok.

That might explain the good reliability point then. ;-)

;-)

Well, maybe, or a reputation to up hold?

There are many jobs I have turned down because it was highly likely that I wasn't going to be able to do it to my own (fairly high) standard and / or would be able to do it 'comfortably' and up to a reasonable level of general acceptance by those who know.

IDC (within reason) how long it takes to do it right, right is the only way I want to do it. [1]

If I need to solder something up and want to do so in a way where it's right first time, is safe and reliable and I can't find my 'soldering' glasses or the right solder, I'll not do it till I have.

Cheers, T i m

So, it's just a matter of taking a deep breath, cutting the plug off, cleaning up the connectors (threading the shroud on) and starting again whilst aiming for the same standard. ;-)

How far back to you want to go? And yes, in general a properly made crimp on a connector is better than a soldered joint to the terminals. Heating the cable through soldering stresses the end of the cable.

You'll note I'm talking about a plug in connector. Like the BNC in question. Not the difference between something soldered direct.

BNC crimp tools, being mass produced, are relatively cheap for a top quality one. Unlike more specialised crimp tools which can be very expesive.