Coax recommendation


Martin - G8JNJ
 

On Sat, Jan 14, 2023 at 12:40 AM, Rob Q wrote:
By the way, my F to BNC adapter broke.
Unfortunately they are manufactured from two halves which are a tight compression fit, and they will occasionally pull apart.

You can reassemble them by squeezing the two halves back together again in a vice. and if you are careful using a blow torch and a damp rag, you can often quickly run a seam of solder along the joint, and then quench it before the insulation melts (it's usually not entirely heat resistant).

Regards,

Martin


Rob Q
 

On Tue, Jan 10, 2023 at 12:58 PM, Tom Seeger wrote:
Or.... You could just buy a bag of F connectors and a crimp tool for about $25 USD and just cut off and replace the connection it fails. Replacement takes less than a minute to do. I have been using F connectors outside for about 10 years on 3 different antennas. Two of my lines are partially buried. One coax feed line runs on top of the ground and has an F to F coupler half way. I do use outdoor rated RG-6Q and outdoor rated F connectors. But I use no tape or sealant of any kind. Here in Canada my feedlines are subjected to rain, snow, ice and heat. In 10 years have had exactly zero failures with any feed line or connection. Your circumstances my be different, but for me its just a hobby not a critical commercial communications link.
73 Tom
I have tons of F connectors for outdoors. I do wonder why the LAA++ was made with BNC connectors, it's a challenge to find a cable that's rated 50 ohms, unless you're willing to take RG-58. To bad it wasn't an SO239 connector, since there's more available which can be used outdoors. I'll see what I can do with my RG-6Q and BNC connectors. They're indoor but it was either that or nothing. If that doesn't work, I'll swap it with RG-8X with preinstalled waterproof BNC connectors and call it a day. 40 feet is a bit short though. Too cold to do anything outdoors, good project for Spring. In the mean time....research and do my homework.

By the way, my F to BNC adapter broke. The BNC connector on the adapter is really loose that it's not keeping a solid connection in the bias-t unit.


David Cutter
 

If regular use of the connector is envisaged, it could housed in a water proof box with compression glands.  I once modified a deodorant bottle (remove ball) with grommets to do this.  This is also good if you anticipate leaving a connector on the ground where it can be stood on. 

 

David G3UNA

 

From: CrossCountryWireless@groups.io <CrossCountryWireless@groups.io> On Behalf Of Martin - G8JNJ via groups.io
Sent: 11 January 2023 11:56
To: CrossCountryWireless@groups.io
Subject: Re: [CrossCountryWireless] Coax recommendation

 

On Tue, Jan 10, 2023 at 04:27 PM, Rob Q wrote:

How is this method for if you have to take it off to do any repairs or modifications? I've noticed that the Denso Tape is about double the price of the other two tapes. It actually "looks" like it's a messy item to work with. haha!

It is awful stuff to work with but it is extremely effective, and has been in pretty standard use on commercial tower installations for as long as I can remember.

Use heavy duty rubber gloves, or nothing at all.

It will take ages to clean it off your skin, but you will have lovely soft hands afterwards :-)

Regards,

Martin


Martin - G8JNJ
 

On Tue, Jan 10, 2023 at 04:27 PM, Rob Q wrote:
How is this method for if you have to take it off to do any repairs or modifications? I've noticed that the Denso Tape is about double the price of the other two tapes. It actually "looks" like it's a messy item to work with. haha!
It is awful stuff to work with but it is extremely effective, and has been in pretty standard use on commercial tower installations for as long as I can remember.

Use heavy duty rubber gloves, or nothing at all.

It will take ages to clean it off your skin, but you will have lovely soft hands afterwards :-)

Regards,

Martin


Tom Seeger
 

Hi Rob. I'm in Cambridge. I've used all those plus hamfests and kijiji. But except for my receivers, I mostly build my own stuff.
Tom


Rob Q
 
Edited

On Tue, Jan 10, 2023 at 12:58 PM, Tom Seeger wrote:
Or.... You could just buy a bag of F connectors and a crimp tool for about $25 USD and just cut off and replace the connection it fails. Replacement takes less than a minute to do. I have been using F connectors outside for about 10 years on 3 different antennas. Two of my lines are partially buried. One coax feed line runs on top of the ground and has an F to F coupler half way. I do use outdoor rated RG-6Q and outdoor rated F connectors. But I use no tape or sealant of any kind. Here in Canada my feedlines are subjected to rain, snow, ice and heat. In 10 years have had exactly zero failures with any feed line or connection. Your circumstances my be different, but for me its just a hobby not a critical commercial communications link.
73 Tom

I can do that no problem! Where in Canada are you, Tom? I'm in the Niagara Region.

The majority of my radio gear comes from Radio World, Durham Radio (too bad they closed shop) and Amazon.


Tom Seeger
 

Or.... You could just buy a bag of F connectors and a crimp tool for about $25 USD and just cut off and replace the connection it fails. Replacement takes less than a minute to do. I have been using F connectors outside for about 10 years on 3 different antennas. Two of my lines are partially buried. One coax feed line runs on top of the ground and has an F to F coupler half way. I do use outdoor rated RG-6Q and outdoor rated F connectors. But I use no tape or sealant of any kind. Here in Canada my feedlines are subjected to rain, snow, ice and heat. In 10 years have had exactly zero failures with any feed line or connection. Your circumstances my be different, but for me its just a hobby not a critical commercial communications link.
73 Tom


Rob Q
 

On Tue, Jan 10, 2023 at 06:17 AM, Chris Moulding wrote:
OK let's do the job properly. This is how I used to waterproof coax cables and connectors professionally back in the day.

First layer is Scotch 88 vinyl tape. This is slightly stretchy tape that can make a good waterproof layer on it's own for temporary jobs. Do a 50% overlap as you wind it on. Don't use cheap PVC electricians tape it won't last, the adhesive is poor and it will fall off.

Second layer is a layer of self-amalgamating tape. Do a 50% overlap and then knead the tape together so that it seals all the gaps. Self-amalgamating tape on it's own exposed to weather lasts about 18 months in the UK due to UV deterioration. In other countries like Australia it probably falls off in a month.

The third and final layer is Denso Tape. This is a petrolatum tape used for corrosion protection on steel pipes used underwater. Think of it as being like Vaseline on a thick cotton tape and you are pretty close. Again a 50% overlap. Now this stuff is messy and I always had to use my bare hands to work it. It just stuck to any gloves I tried so use your hands but have your hand cleaner ready after. This gives the final protection to the cable and connector and keeps weather and UV off the self-amalgamating layer.

A few years back I had to move a cable I protected like this 30 years before. The outer layer of Denso Tape had a discoloured hard weathered surface crust but as I cut through it the self-amalgamating tape and the Scotch 88 tape it was like the day it was taped up 30 years before.

OK some links:

Scotch 88 Vinyl tape

Denso Tape

I know that Denso Tape is a UK company but I'm sure that there must be local equivalents worldwide.

Regards,

Chris
How is this method for if you have to take it off to do any repairs or modifications? I've noticed that the Denso Tape is about double the price of the other two tapes. It actually "looks" like it's a messy item to work with. haha!


Rob Q
 

On Tue, Jan 10, 2023 at 01:46 AM, John Buckley wrote:
"for indoor use only" !!
Yeah, I saw that. It was my first concern. I wonder if BNC connectors even can be used outdoors. If they can, it might require some work to protect it.


Chris Moulding
 

Denso Tape is your friend but you won't think that when you are using it!

Regards,

Chris


Phil Nicholson
 

Chris is right about the temporary aspect of self-amalgamating tape; whilst it's an easy solution, I always renew it every year minimum for the connection on my Wellbrook loop.
I defer to his guidelines for a proper job.

On Tue, 10 Jan 2023 at 11:17, Chris Moulding <chrism@...> wrote:
OK let's do the job properly. This is how I used to waterproof coax cables and connectors professionally back in the day.

First layer is Scotch 88 vinyl tape. This is slightly stretchy tape that can make a good waterproof layer on it's own for temporary jobs. Do a 50% overlap as you wind it on. Don't use cheap PVC electricians tape it won't last, the adhesive is poor and it will fall off.

Second layer is a layer of self-amalgamating tape. Do a 50% overlap and then knead the tape together so that it seals all the gaps. Self-amalgamating tape on it's own exposed to weather lasts about 18 months in the UK due to UV deterioration. In other countries like Australia it probably falls off in a month.

The third and final layer is Denso Tape. This is a petrolatum tape used for corrosion protection on steel pipes used underwater. Think of it as being like Vaseline on a thick cotton tape and you are pretty close. Again a 50% overlap. Now this stuff is messy and I always had to use my bare hands to work it. It just stuck to any gloves I tried so use your hands but have your hand cleaner ready after. This gives the final protection to the cable and connector and keeps weather and UV off the self-amalgamating layer.

A few years back I had to move a cable I protected like this 30 years before. The outer layer of Denso Tape had a discoloured hard weathered surface crust but as I cut through it the self-amalgamating tape and the Scotch 88 tape it was like the day it was taped up 30 years before.

OK some links:

Scotch 88 Vinyl tape

Denso Tape

I know that Denso Tape is a UK company but I'm sure that there must be local equivalents worldwide.

Regards,

Chris



--
Regards
Phil Nicholson


Chris Moulding
 

OK let's do the job properly. This is how I used to waterproof coax cables and connectors professionally back in the day.

First layer is Scotch 88 vinyl tape. This is slightly stretchy tape that can make a good waterproof layer on it's own for temporary jobs. Do a 50% overlap as you wind it on. Don't use cheap PVC electricians tape it won't last, the adhesive is poor and it will fall off.

Second layer is a layer of self-amalgamating tape. Do a 50% overlap and then knead the tape together so that it seals all the gaps. Self-amalgamating tape on it's own exposed to weather lasts about 18 months in the UK due to UV deterioration. In other countries like Australia it probably falls off in a month.

The third and final layer is Denso Tape. This is a petrolatum tape used for corrosion protection on steel pipes used underwater. Think of it as being like Vaseline on a thick cotton tape and you are pretty close. Again a 50% overlap. Now this stuff is messy and I always had to use my bare hands to work it. It just stuck to any gloves I tried so use your hands but have your hand cleaner ready after. This gives the final protection to the cable and connector and keeps weather and UV off the self-amalgamating layer.

A few years back I had to move a cable I protected like this 30 years before. The outer layer of Denso Tape had a discoloured hard weathered surface crust but as I cut through it the self-amalgamating tape and the Scotch 88 tape it was like the day it was taped up 30 years before.

OK some links:

Scotch 88 Vinyl tape

Denso Tape

I know that Denso Tape is a UK company but I'm sure that there must be local equivalents worldwide.

Regards,

Chris


Tom Crosbie G6PZZ
 

You need to buy something called “Self-Amalgamating Tape”. This isn’t sticky but it stretched around the joint/connector. As it shrinks it becomes solid. Electrical tape is not waterproof. This stuff is once cured. If I make up F connectors for my TV stuff, I use self-amalg to keep the connector on the cable.

 

From: CrossCountryWireless@groups.io <CrossCountryWireless@groups.io> On Behalf Of John Buckley
Sent: 10 January 2023 06:47
To: CrossCountryWireless@groups.io
Subject: Re: [CrossCountryWireless] Coax recommendation

 

"for indoor use only" !!

 

On Mon, 9 Jan 2023 at 23:24, Rob Q <robman501a@...> wrote:

I'm going to get this from Amazon and ditch the F to BNC adapters. As for weatherproofing, I've just covered the connector with lots of electrical tape as I tightly wrapped it around. Hope that will do the job.


John Buckley
 

"for indoor use only" !!


On Mon, 9 Jan 2023 at 23:24, Rob Q <robman501a@...> wrote:

I'm going to get this from Amazon and ditch the F to BNC adapters. As for weatherproofing, I've just covered the connector with lots of electrical tape as I tightly wrapped it around. Hope that will do the job.


Simon
 

Regards the electric tape..no

Self amalgamating tape is what you WANT..


DougH
 

Invest in self amalgamating tape what you are using is rubbish---it will leak!

D

On 09/01/2023 23:24, Rob Q wrote:

[Edited Message Follows]

I'm going to get this from Amazon and ditch the F to BNC adapters. As for weatherproofing, I've just covered the connector with lots of electrical tape as I tightly wrapped it around. Hope that will do the job.


Oh, and I do plan to ditch the RG-6Q and replace it with an LMR-400 equivalent for my 25 - 1300 MHz discone since that has an 95' run to the radio. It also does have the UHF connector and I've noticed that UHF reception is poor (the 40cm band for example). Depending on how things go, the discone will be replaced with the Broadband Active Antenna.



Rob Q
 
Edited

I'm going to get this from Amazon and ditch the F to BNC adapters. As for weatherproofing, I've just covered the connector with lots of electrical tape as I tightly wrapped it around. Hope that will do the job.


Oh, and I do plan to ditch the RG-6Q and replace it with an LMR-400 equivalent for my 25 - 1300 MHz discone since that has an 95' run to the radio. It also does have the UHF connector and I've noticed that UHF reception is poor (the 40cm band for example). Depending on how things go, the discone will be replaced with the Broadband Active Antenna.


PA3BCB
 

Hi Rob,
I totally agree with Chris.
The only issue I can think of is how weatherproof your F to BNC adapter is. The usual tv-type F connectors are not high-grade.
Getting water into your coax would be desastrous.
As regards 75 ohm (RG-6) to 50 ohm (RG-213), I would not worry about mismatch loss, especially not up to 30 MHz.
Your RG-6 is low-loss and quad shielded which is a great advantage, RG-213 has only a single shield, is much heavier, more expensive and more difficult to handle.
Personally I use a 100 foot length of Hyperflex-5 with the appropriate BNC connectors. It is higly flexible and double shielded.
Admittedly, I do not use my loop antenna at VHF frequencies, only up to 30 MHz. Loss of Hyperflex-5 is slightly higher than RG-213.

Hope this helps,
Regards and good luck!
Gerard


Chris Moulding
 

Rob,

There's an old saying "If it's working don't fix it!".

The RG-6 quad shield sounds like it's working really well for you especially at VHF where losses are higher. 

The losses with adaptors are minimal at these frequencies so as long as everything is waterproofed keep on using it, enjoy the radio and stop reading coax spec sheets!

Regards,

Chris


Rob Q
 
Edited

Hello, I would like your opinion on this. I to have a question about which coax I should be using.

I have the LAA++ about 4 feet off the ground and I have about 10-11 meters of RG6 quad shield coax running from the LAA++ to the bias-t (which has BNC male to F female adapters on both ends) and then I've got a short 3 foot run of RG-58 (BNC Male) that connects to Ant C on my RSPdx.
The guy at the store told me that if I want to improve my antenna, I should ditch the RG-6 and loose the adapters as they will degrade the signal, but on the other hand, people are telling me that they use RG-6 quad shield coax because of the extra shielding that helps them keep out local RFI. So, I'm confused. Do I keep the RG-6 and adapters or should I find something like RG-213 or RG-8X and put a BNC connector on that? I really don't know what to do as I am getting tons of different answers. 
What are you guys using for the coax? My intention was to only use the LAA++ for 0-30 MHz but it totally kicks butt at 87 - 108 MHz, and the air band. In fact it's the best directional antenna I've ever had for FM radio.