Author Topic: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)  (Read 1164 times)

Online Adagio

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Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« on: February 09, 2017, 11:17:40 AM »

Good morning,

Am wondering which method works best, for replacing TV aerial (UHF Grid) -> with my new FM dipole onto the existing UHF Extrernal Ellies wall bracket.

Will disconnect UHF grid aerial -> mount FM Dipole onto existing external bracket -> then re-splice both cable-ends.


What is the best method of joining the 2 seperate co-axial cables into one? -  :nfi:

Offline Family_Dog

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #1 on: February 09, 2017, 02:13:19 PM »
Resplicing a co-ax cable is a bad idea, you will never get the deired result and quite possibly introduce moisture in to the cable. As I understand it, you are removing the TV Grid antenna and in its place fitting a VHF FM Yagi antenna? Is the cable too short? Ideal thing would be to lay a new RG6 cable especially if the old one has seen exposure to the outside elements.


-F_D



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Online dekardy

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #2 on: February 09, 2017, 02:32:58 PM »
Not sure what it would do to quality but will something like this with shrink wrap not work?



Offline Hi-Phibian

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #3 on: February 09, 2017, 03:11:12 PM »
Yes but not shrink.  Use self amalgamating /vulcanising  tape. 

Connector at RF will always have some loss so best avoided I guess. 


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Online Adagio

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #4 on: February 09, 2017, 05:10:49 PM »
Not sure what it would do to quality but will something like this with shrink wrap not work?




Exactly what I had in mind: 2 x male connectors with female joining piece.

Will see if available at Yogi's.

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #5 on: February 09, 2017, 05:16:17 PM »
Yes but not shrink.  Use self amalgamating /vulcanising  tape. 

Connector at RF will always have some loss so best avoided I guess. 


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So no soldering involved here at all ? (in other words)

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #6 on: February 09, 2017, 05:45:43 PM »
Resplicing a co-ax cable is a bad idea, you will never get the deired result and quite possibly introduce moisture in to the cable. As I understand it, you are removing the TV Grid antenna and in its place fitting a VHF FM Yagi antenna? Is the cable too short? Ideal thing would be to lay a new RG6 cable especially if the old one has seen exposure to the outside elements.


-F_D
Quite right F_D, - will replace the TV grid antenna with a FM dipole aerial. (the satellite dish can then take care of TV signal.)

Was going to use the existing co-ax wire & join the two together, but makes perfect sense to replace the entire run, as has seen plenty of UV from being exposed on the external East facing wall.

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #7 on: February 10, 2017, 09:30:01 PM »

Where is the best place to obtain decent RG-6 co-ax cable, - will be heading out to Cape Town tomorrow. >>

Offline Family_Dog

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #8 on: February 10, 2017, 09:34:06 PM »
You can try Cerilog, not sure just where in CT they are, or even if they're open on Saturdays. They will have the decent stuff, not the rubbish sold by TV shops.

Cerilog CT   
Phone: 021 948-9826   
Contact: Andrew Venables


-F_D



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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #9 on: February 10, 2017, 10:11:19 PM »
You can try Cerilog, not sure just where in CT they are, or even if they're open on Saturdays. They will have the decent stuff, not the rubbish sold by TV shops.

Cerilog CT   
Phone: 021 948-9826   
Contact: Andrew Venables


-F_D

Got it, - many thanks F_D!  >> :)




Edit:

Address: 7530, 0A Tienie Meyer Bypass, Bellville, Cape Town, 7530, South Africa
Phone: +27 21 948 9826.
« Last Edit: February 10, 2017, 10:16:27 PM by Adagio »

Offline chrisc

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #10 on: February 11, 2017, 08:44:30 AM »
I will give you some.  Have an unused 100m reel here (as long as you don't need the lot).  Plus some f-connectors and couplers

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #11 on: February 11, 2017, 11:13:47 PM »


Chris -  :faint: , this may just be what am looking for (am flat broke) - will probably drop by before collecting the new Bosch fridge tomorrow late afternoon, or if Monday just before collecting the 2 Germans from the airport at 14:00.

Nevertheless, will PM further when 100%. >>




* - Will certainly assist with the DSTV dish install, as together with the FM dipole looking at  +- total of 45 meters. (3 x 15 meters each)

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #12 on: February 11, 2017, 11:32:37 PM »
You can try Cerilog, not sure just where in CT they are, or even if they're open on Saturdays. They will have the decent stuff, not the rubbish sold by TV shops.

Cerilog CT   
Phone: 021 948-9826   
Contact: Andrew Venables


-F_D

Found the shop this morning, - though sadly they were closed. >>  :(



* - will be back though.

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #13 on: March 08, 2017, 07:12:23 AM »
Hi F_D, went into Cerilog once again in CT to get some RG-6 though they only can supply 50-ohm cable by the bulk.

The chap was very helpful about the whole thing and was willing to get some from Joburg if necessary.

He also mentioned that I could try Regal Security as they do extensive CCTV installations and are in the same Business Park, so that's what I did.

Again the Regal chap was unable to assist as not being a trade dealer, though advised Bright's Hardware, where I found Ellies 'DSTV Approved' RG-6 @ R4.80 per metre promptly buying 20m, and pulled it through my lounge conduit and ceiling on the week-end.

Now for an extra question: does the FM dipole ideally be need to be mounted outside, or would indoors ie. oriented vertically inside on the roof rafters do?

Offline chrisc

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Re: Joining 2 seperate (bare) pieces of co-ax cable. (FM dipole)
« Reply #14 on: March 08, 2017, 08:32:15 AM »
In the roof rafters is fine.  As long as the roof is not made of steel or slate.  Steel attenuates 80% of the signal, slate about 50%.  Everything else is invisible to radio frequency waves at around 100MHz