Joining RG-8X co-ax

[JayBee]

I am about to upgrade my VHF installation with a Metz antenna and RG-8X co-ax, which is somewhat heavier and a lot less "lossy" than the usual RG-58, normally found on yachts. The connection to the antenna and the set will be by PL259 plugs, supplied already fitted to the co-ax. My (not unusual) problem is that I will need to cut the cable close to the mast heel, but under the deck, and need to find a suitable means of re-connection.

The first option is to use two more PL259s with a PL263 short connector. I don't like this, as it requires the soldering of two plugs in a confined space and leaves me with a bulky connector to pass though a gland at the mast foot when I step/unstep the mast. I also don't want to make this connection externally.

On a previous boat I had success with much smaller 50 ohm crimp/crimp bnc connectors for this job, for which I have a ratchet tool with the correct dies. I have spent half a day trying to source these connectors without success. They are common across the pond, but the nearest I have got to a UK supplier is Digi-Key, who have a minimum order of 10 units and an extended stock surcharge of £10, plus carriage, VAT and so on , for a total of over 30 quid. I only need one plug and one jack.

If anyone knows where I can find these as stock items in the UK, I would be very pleased to hear about it, or alternatives. The Amphenol part numbers are 11253 (plug) and 112605 (jack).

 

[Plevier]

RS Components have both of those min qty 5.
Did you get your stuff from SaltyJohn, doesn't he have any connectors?
Alternatively look for a ham radio shop.

 

[prv]

Did you get your stuff from SaltyJohn, doesn't he have any connectors?

He has the barrel connectors for PL259s, which the Op says he doesn't want. Not much point John stocking these crimp connectors as most people won't have the tool.

Pete

 

[David2452]

Maplins sell them in both 50 & 75 Ω flavours. By the way, hang on to that tool, the small pin crimp is ideal for Deutch barrel pins and saves buying theirs at hundreds of beer vouchers.

 

[lw395]

I am about to upgrade my VHF installation with a Metz antenna and RG-8X co-ax, which is somewhat heavier and a lot less "lossy" than the usual RG-58, normally found on yachts. The connection to the antenna and the set will be by PL259 plugs, supplied already fitted to the co-ax. My (not unusual) problem is that I will need to cut the cable close to the mast heel, but under the deck, and need to find a suitable means of re-connection.

The first option is to use two more PL259s with a PL263 short connector. I don't like this, as it requires the soldering of two plugs in a confined space and leaves me with a bulky connector to pass though a gland at the mast foot when I step/unstep the mast. I also don't want to make this connection externally.

On a previous boat I had success with much smaller 50 ohm crimp/crimp bnc connectors for this job, for which I have a ratchet tool with the correct dies. I have spent half a day trying to source these connectors without success. They are common across the pond, but the nearest I have got to a UK supplier is Digi-Key, who have a minimum order of 10 units and an extended stock surcharge of £10, plus carriage, VAT and so on , for a total of over 30 quid. I only need one plug and one jack.

If anyone knows where I can find these as stock items in the UK, I would be very pleased to hear about it, or alternatives. The Amphenol part numbers are 11253 (plug) and 112605 (jack).

http://uk.farnell.com/amphenol-connex/112533rp/rf-coaxial-bnc-rp-plug-str-50ohm/dp/1791189

 

[Plevier]

Maplins sell them in both 50 & 75 Ω flavours. By the way, hang on to that tool, the small pin crimp is ideal for Deutch barrel pins and saves buying theirs at hundreds of beer vouchers.

I think they only have them for RG58 not RG8X - check before going!

 

[BERT T]

I had the same problem when I went looking for an N type connector for RG8X. Digi-Key were crazy prices, ended up getting them from US for about a third of the price including postage. For some unknown reason nobody in the UK stocks anything other than PL259's for RG8X.

 

[JayBee]

http://uk.farnell.com/amphenol-connex/112533rp/rf-coaxial-bnc-rp-plug-str-50ohm/dp/1791189

Yes, well, been there, but your link is for a reverse polarity plug - says 500 ohms , but that's most likely a mistake and there is a delivery charge of £15.95, plus, plus....

Might have to bite the bullet, tho.

Thanks anyway.

 

[Mirror Painter]

May I ask how long the coax run is? I ask because it may be this additional hassle for lower loss coax is not worth it. But if you've already considered all that ignore me

 

[JayBee]

It's about 28m. I have already got the RG-8X and have been sold on the idea by SaltyJohn, so he's to blame

 

[lw395]

Yes, well, been there, but your link is for a reverse polarity plug - says 500 ohms , but that's most likely a mistake and there is a delivery charge of £15.95, plus, plus....

Might have to bite the bullet, tho.

Thanks anyway.

I would check the Amphenol part number against their datasheet, there's a link to it on Farnell's page:
http://www.amphenolconnex.com/media/downloads/5648/bnc.pdf

Delivery does sound a bit steep, being in the trade, it's normally free.
You could try eBay or any Radio Ham forums.

 

[Mirror Painter]

Fair enough - that's a reasonable run. By the way, the connector in the link above is 50 Ohms - I think you fell for the optical illusion and thought it said 500 Ohms. I am a (almost lapsed) radio ham but would buy R.F. connectors from e-bay - there's bound to be dozens of H.K. sellers with exactly what you need.

 

[BERT T]

Maplins sell them in both 50 & 75 Ω flavours. By the way, hang on to that tool, the small pin crimp is ideal for Deutch barrel pins and saves buying theirs at hundreds of beer vouchers.

Maplins plugs only fit RG58 and UR76 not RG8X which is 6.1mm diameter.

JayBee, are the dies on your crimping tool for RG8X. If they are for RG58 I don't think they will work on RG8X.

 

[JayBee]

RS Components have both of those min qty 5.
Did you get your stuff from SaltyJohn, doesn't he have any connectors?
Alternatively look for a ham radio shop.

Same problem with RS as with Digi-Key. £33.78 minimum charge and 8 plugs/jacks surplus to requirements.

 

[JayBee]

JayBee, are the dies on your crimping tool for RG8X. If they are for RG58 I don't think they will work on RG8X.

Good point. The dies I need are: .068, .213, .255
I seem to remember that's what I have, but the crimper is on the boat in Portugal and I am in bonny Scotland. I'll be able to check next month, but more heavy duty googling looms, if I need to change the dies.

 

[Gumpy]

Look for n-type connectors not crimp but screw and water resistant.
Ebay have them for about 6quid a pair.
Less loss than pl259 also rg213 is about the same as rg8 so 213 commextors will ususlly fit 8. Having said that most of the rg8 I have seen recently is 213
One of these
http://www.ebay.co.uk/itm/VITELEC-V...ion_Video_Cables_Adapters&hash=item1e6ea2a82a
And one of these
http://www.ebay.co.uk/itm/Nickel-N-...munication_Radio_Antennas&hash=item3379be8d81

Will do it

 

[JayBee]

Look for n-type connectors not crimp but screw and water resistant.
Ebay have them for about 6quid a pair.
Less loss than pl259 also rg213 is about the same as rg8 so 213 commextors will ususlly fit 8. Having said that most of the rg8 I have seen recently is 213
One of these
http://www.ebay.co.uk/itm/VITELEC-V...ion_Video_Cables_Adapters&hash=item1e6ea2a82a
And one of these
http://www.ebay.co.uk/itm/Nickel-N-...munication_Radio_Antennas&hash=item3379be8d81

Will do it

Unfortunately, RG-8 and RG-213 are completely different animals to RG-8X.

Big table, here:

http://en.wikipedia.org/wiki/Coaxial_cable.

Confusing, innit?

Thanks anyway.

 

[whipper_snapper]

It is highly desirable to avoid any connection at all, and often possible for this kind of application.

Put a gland on deck that will allow a PL259 pass through and run it direct to the radio without a connection, tidying it away with easily removed clips. When you need to drop the mast, you remove from the radio and pass the whole lot out.

 

[Gumpy]

Unfortunately, RG-8 and RG-213 are completely different animals to RG-8X.

Big table, here:

http://en.wikipedia.org/wiki/Coaxial_cable.

Confusing, innit?

Thanks anyway.

Missed the X never had reason to use 8x , always used 213 for short links, ldf450 or ldf550 for long runs but not on a boat.

 

[john_morris_uk]

It is highly desirable to avoid any connection at all, and often possible for this kind of application.

Put a gland on deck that will allow a PL259 pass through and run it direct to the radio without a connection, tidying it away with easily removed clips. When you need to drop the mast, you remove from the radio and pass the whole lot out.

Regrettably its not always possible to re-route the cable all the way to the radio whenever you lower the mast. On our boat it would be totally impractical.

An alternative to PL259's and an inline connector would be solder on type BNC connectors. RF wise they are vastly superior to PL259s and you can get inline male and female so you wouldn't need an inline back to back between two plugs. They are slightly fiddly to fit, but with patience and a steady hand and a set of instructions that you follow TO THE LETTER regarding measurements of how much wire to strip etc at each stage they are not too bad.