BNC connectors

lustyd

lustyd

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Playing with BNCs at the mo and feeling frustrated.
RG58 and RG58 c/u require different connectors but I’m struggling to work out how to find the correct ones from standard suppliers.

Anyone with experience here able to shed some light for me? Is there some specific code I need to look for? Is there a table with cable/connector types somewhere?

Also any hints for a good crimp tool where I can just buy the dies going forwards would be great. I have so may sets now and the dies aren’t all interchangeable (and half of them aren’t even good dies)
 
Why BNC? What are you using this for?

Type "N" is almost always best for use on a boat. Reasonably waterproof and extremely low insertion loss.

Normally crimp the shield but solder the central conductor. Crimp tools for coax are generally better just bought for the specific application. I have a bag full of them.
 
Took a look and for this purpose there doesn’t seem to be any real difference in the connectors but the question would remain the same since the pins will still be sized for solid or stranded cores. Searching for connectors seems just as hard either way.
 
It is a bit of a black art. There is a lot more to it than you think. When I was using them regularly many years ago I found the best make was Greenpar. Available from Farnell amongst others.

I prefer the old school sort where you assemble the parts with a spanner and the braid is clamped as you tighten the nut. These are known as "clamp on" The trouble with the crimp sort, the centre pin is not captive and can creep under certain circumstances.

But I have only known them sized on the cable size, and all variants of RG58 are the same size as far as the connectors are concerned.
 
ProDave said:
But I have only known them sized on the cable size, and all variants of RG58 are the same size as far as the connectors are concerned.
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Sadly not the case. Standard rg58 is solid core which is thinner than rg58 c/u stranded core. The standard plugs won’t fit on stranded wire. I have found some plugs for stranded wire but not many and they are expensive and very hard to find.
 
lustyd said:
For the break in the VHF cable
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At the mast base? I would suggest Type N for that -- much more robust, waterproof, lower insertion loss. Downside is it's bulkier and more expensive.

Better yet don't break the cable there. Just have a continuous run from antenna to the radio. That's what I did when I rewired my mast 12 years ago. Unless you pull your mast often, this works fine -- you just have the extra work of pulling the cable out before taking the mast out.

Correction: I double-checked the insertion loss tables, and at marine VHF frequencies there's not much to choose between Type N and BNC. Both much better than UHF connectors. But mechanically, and in terms of waterproofing, Type N vastly superior to BNC.
 
RG58 is quite an old design - there are much better, lower loss cables available these days for a similar price to chandlery RG58.

Somewhere like Nevada Radio is great for ringing up and getting advice on cable and connectors
 
Useless fact. the actual inner workings of a BNC and N type are almost identical, go on try it, an N plug will plug into a BNC socket. It won't latch of course so don't expect to use it like that but that shows why there is little to choose between them in terms of electrical performance.

You must have been unlucky, or it is a recent thing, but every BNC I have used the hole in the pin is large enough for both the solid and stranded inner cores. In the unlikely event I found one too small I would just get my miniature drills out and enlarge the hole.

For my own boat I am just fitting a deck mounted N type socket and plug this winter replacing the poor in line connection that was there before. Our mast is dropped each winter for crane out so needs to be detachable.
 
Dockhead said:
But mechanically, and in terms of waterproofing
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Neither are important to me since it’s inside and waterproofing is only better on the connection anyway, not the back of the plug. There’s nothing to interfere with the cables above the headlining either so mechanical strength isn’t needed. I don’t disagree that n connectors might be better.

Either way, finding the right one seems very hard. Nobody seems to allow filtering based on cable type, and those that do didn’t normalise the data so there are hundreds of permutations to select.
 
ProDave said:
You must have been unlucky,
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I thought so too until i Googled and it’s a very common issue. Even the reviews of the plug I bought had a bunch of people complaining their marine cable didn’t fit, many having no realisation it wasn’t RG58.
ProDave said:
For my own boat I am just fitting a deck mounted N type socket and plug
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I’d strongly recommend putting the join below deck with a gland instead. I had a deck socket previously and it’s not a good solution as water will get in. The N connector crimps the same from the back so although there’s an O-ring at the front, I wouldn’t consider it weatherproof especially for long term exposure with a vertical cable.

Needless to say that’s not experience talking, this thread is the first time I’ve seen the n connectors. I can’t see anything suggesting I’m wrong though, the back is fully open to the elements and will let moisture wick into the outer conductor, turning it to dust.
 
lustyd said:
I’d strongly recommend putting the join below deck with a gland instead. I had a deck socket previously and it’s not a good solution as water will get in. The N connector crimps the same from the back so although there’s an O-ring at the front, I wouldn’t consider it weatherproof especially for long term exposure with a vertical cable.

Needless to say that’s not experience talking, this thread is the first time I’ve seen the n connectors. I can’t see anything suggesting I’m wrong though, the back is fully open to the elements and will let moisture wick into the outer conductor, turning it to dust.
Click to expand...
I have to work with what I have. the cable from the bottom of the mast is not long enough to pass through for an internal joint. I am replacing a poor in line joint with a better deck mounted joint. The N plug is one with a side / 90 degree cable entry so much easier to waterproof, and I have made a cover to cover the whole connection both when mated and to keep water off the socket in winter when the mast is down.

Both N and BNC have a rudimentary O ring seal around the cable (the clamp on types of connector) and I will be supplementing that with a cable boot and self amalgamating tape.
 
After borrowing a couple of different pairs from work, I bought a set of Greenpar 30040 from eBay. They needed the tension adjusting, but that was a 5 min process.
 
Very similar to the pair I ended up with. The frustration is the number of sets of handles I've accumulated on board.

I looked into it a bit more and you can buy the frame from electrical suppliers, and then matching dies. The problem then is that the dies are £50 a set so double the cost compared to just buying the whole tool cheaply. Obviously the crimps will be better, but that's a crazy difference, and the crimps would only be better if I were also able to find quality parts to crimp, which also seems impossible :ROFLMAO:
 
RG58 isn’t recommended for cable runs of more than 8m.
I went with RG8X and ran it strait from the masthead to the VHF via a scan strut gland. It’s a straight run above the headlining panel so when the mast comes down it’s not horrible to take it out.
 
samfieldhouse said:
RG58 isn’t recommended for cable runs of more than 8m.
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Everything I can find says 15m. Thankfully it’s rg58 c/u which isn’t the same stuff anyway.

Standard RH58 is the normal on yachts though, not a problem at all other than being solid core untinned cable. Both of which C/U fixes along with a thicker, stranded core.

8x is much thicker so harder to run and has radius issues.
 
lustyd said:
Neither are important to me since it’s inside and waterproofing is only better on the connection anyway, not the back of the plug. There’s nothing to interfere with the cables above the headlining either so mechanical strength isn’t needed. I don’t disagree that n connectors might be better.

Either way, finding the right one seems very hard. Nobody seems to allow filtering based on cable type, and those that do didn’t normalise the data so there are hundreds of permutations to select.
Click to expand...
Just call the guys at Nevada Radio. They'll fix you up.
 
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