BEware the cheap BNCs can cost more than you save

[Numb-nuts 1]

As we al know, that installation can be an expensive business especially with the

amount of materials we have to use when we choose NOT to cut corners.

It's therefore no surprise that when a trusted supplier offers one of your regularly

used products at a really low price.

 

The parable of the crimp on BNC.

 

I am always looking to save money on crimp connectors, BNCs, wire end ferrules, cable ties etc

When my first choice supplier starts to offer BNC crimps at £11.000 per 10 I am thinking 'oh goody that'll save me a ££££££' so I order a couple hundred and confidently take them out of their bags to use making fly leads for my 4 way Balun receiver.

 

Obviously I am not going to mention the supplier since it may just be that they aren't yet aware of this problem.

It's NOT the first quality supplier who's BNC offering has turned out to disappoint.

 

These damn crimps look great but thats where the great STOPS. I prepare the cable with a proper 3 blade wire stripper and trim the center core to ensure proper seating of the center pin onto the dielectric, clear the braid ready to receive the plug body nad then insert the ping until there is a distinct click of the center pin engaging, only thing is the click is not particularly distinct except by it's abscence or it's dullness. I then pull up the outer ferrule and crimp that. Then I pull up the cable boot I purchased seperately as I like to use the Greenpar ones which are tight. Only problem is that as fast as I can install these plugs they are dropping off with the slightest tug even when dressing the cables into a bundle. NOT ONLY ARE THE CENTER PINS DISENGAGING, THE CRIMP FERRULES AREN'T HOLDING ONTO THE BRAID. THE ONLY THING THAT IS HOLDING IS THE CABLE BOOTS ONTO THE FERRULES and I supplied those.

 

NOW IF I'D GONE AWAY AND LEFT THAT AND THESE HAD COME OFF I WOULD HAVE TO RETURN COSTING ME A CALL OUT THAT I CANNOT CHARGE. MULTIPLY THAT BY EVERY JOB I HAVE DONE SINCE I STARTED USING THESE PLUGS AND THEY DON'T LOOK SO CHEAP ANYMORE. PHOOOOOOOOEEEEY! fortunately enough, this was the first job i'd used these nasty plugs so I took them all off and I'll be replacing them all with some others I have in reserve, tomorrow.

 

TOMORROW A that supplier is getting a strongly worded email and I will be demanding not only that they collect the whole lot but also that they pay their courier to collect them. I have had some dodgy BNCs before but these were simply the WORST EVER.

 

Oh so you think it was my Weidmuller crimping tool that cost an arm and a leg and has been outperforming other toolks for over 20 years, when I used it for RG58 50 ohm plugs in the radio comms industry? I too had my doubts, so I tried my apprentices Pressmaster crimping tool that is a fabulous quality tool, same result. ITS THE PLUGS NOT THE CRIMP TOOL.

 

I have only just recovered from a batch of rubbish baluns now I pay a bit more and they never fail me. I suppose I'm going to have to bite the bullet on BNCs too after this experience.

 

UPDATE: I'm going back to the more expensive ones I usually use, at least with those I could sleep soundly in the knowledge they won't fall off., but at double or more the price.

 

COME BACK TRANSRADIO, ALL IS FORGIVEN

[ssnapier 0]

I had a similar experience with a HUGE distributor. We bought some LMR-600 and connectors to install part of a wireless system on a water tower. Since these connectors would be in some rough conditions we bought the solder type connectors to ensure good contact. The center pins themselves were decent enough, but the rest of the connector was complete garbage. The slightest twist or tug on the connector after assembly caused the braid to be ripped to shreds or just cut so that I lost my shielding.

 

I called the distributor and told them about the issues. They were very apologetic and offered to send my factory assembled cables at no charge, so I calmed down and waited on the cables to arrive. When we get them I gave them a few torture tests to make sure these were not junk, and one connector was a bit loose so I disassembled it to see what was wrong and I noticed that these were crimp style connectors instead of solder like I specifically demanded. That was the last straw... I sent the entire lot back, paid their BS restocking fees and never bought another thing from them.

[Numb-nuts 1]

[*]

I had a similar experience with a HUGE distributor. We bought some LMR-600 and connectors to install part of a wireless system on a water tower. Since these connectors would be in some rough conditions we bought the solder type connectors to ensure good contact. The center pins themselves were decent enough, but the rest of the connector was complete garbage. The slightest twist or tug on the connector after assembly caused the braid to be ripped to shreds or just cut so that I lost my shielding.

 

I called the distributor and told them about the issues. They were very apologetic and offered to send my factory assembled cables at no charge, so I calmed down and waited on the cables to arrive. When we get them I gave them a few torture tests to make sure these were not junk, and one connector was a bit loose so I disassembled it to see what was wrong and I noticed that these were crimp style connectors instead of solder like I specifically demanded. That was the last straw... I sent the entire lot back, paid their BS restocking fees and never bought another thing from them.

 

Shame I hope you didn't lose out by not dealing with them again!

When I install bnc crimps, i ensure they are NOT going to be subject to any movement so they are either enclosed in a box or tied down to something that prevents pulling. If they will be subject to repeated engaging disengaging like on a test piece I like the solder or compression connectors, like test leads for my field test monitor.

 

For the task of making patch cables to baluns, I am going to try using URM70 which is identical to RG59 except that the center core is stranded instead of solid. Any thoughts.

[ssnapier 0]

For longer runs that could be problematic, the stranded cable will create a larger magnetic field, which will cause the signal to degrade just at tiny bit faster.

[Numb-nuts 1]

I will ONLY use the URM70 for small patch leads no longer than 1m as I use a lot of passive and active balun receivers, as I now use Cat5 in 99% of my installs. The beauty of using the URM70 is that its more flexible since it has the stranded conductor and of course as I mentioned, I only need to buy the one size BNC crimps.

 

ON THE BNC FRONT TODAY:

I think I may have found a 'dependable' source of BNCs and RJ45s both of which I use a lot. I use the RJ45s not only to connect but also to test cable before wiring after a long cable run in fact I now do this on ALL cable runs. RJ45s allow me to do this quickly and cheaply since even the good ones cost just a few pence each and the existing and the new tester I have makes testing 8 way cat5 a pleasure.

 

The BNCs are a little more expensive again, but cheaper than the US branded ones I have been using before, which were 100% reliable, but heck customers don't want to pay for anything these days and they don't give a damn as long as the system works, you can use tin foil and sticky tape for all they care, the bottom line price is ALL they care about, MOST don't know or deserve the trouble we go to to ensure a good job.

[ssnapier 0]

you can use tin foil and sticky tape for all they care, the bottom line price is ALL they care about, MOST don't know or deserve the trouble we go to to ensure a good job.

 

Amen to that... I can feel that pain 10000%

[Numb-nuts 1]

My comment about Transradio

 

 

Transradio was a 'British Manufacturer' of coaxial connectors (in Sussex (or was it Surrey? ) who sadly stopped trading sometime after the late 1990's Their product was excellent, comparable to Greenpar, Bowmar, Tyco, Weidmuller Multicomp and all those American manufacturers. Not to be confused with the German company of the same name.