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eHam Forums => Station Building => Topic started by: W3END on December 19, 2010, 09:33:56 AM



Title: Coax entry into basement shack
Post by: W3END on December 19, 2010, 09:33:56 AM
Anyone have pictures of their coax entering into a basement shack? What specific method was used? Thanks


Title: RE: Coax entry into basement shack
Post by: WB8PFZ on December 19, 2010, 10:17:29 AM
I installed glass block windows. The one for the radio room had a dryer duct that I took out the flapper and replaced with a piece of plywood that I drilled for the coax. It worked for me. Mike


Title: RE: Coax entry into basement shack
Post by: K9KJM on December 19, 2010, 10:41:29 PM
The dryer vent idea IS one of the best ones out there.
Only about 5 bucks for the entire dryer vent kit from a discount home supply type store, And the hole saw to install is usually available at most rental type stores for cheap.

Be sure to ground your coax shield right near where it enters the building. 


Title: RE: Coax entry into basement shack
Post by: NN4RH on December 20, 2010, 01:22:12 AM
Anyone have pictures of their coax entering into a basement shack? What specific method was used? Thanks

http://forums.qrz.com/showpost.php?p=1815876&postcount=5


Title: RE: Coax entry into basement shack
Post by: WB2EOD on December 20, 2010, 06:58:10 AM
My antenna system is based on a Glen Martin 9 foot roof mounted tower. 
The coax and control cables run from the tower, along the roof to the edge where they enter the attic through the gable vent.  From there, the cables run alongside the chimney which terminates in the basement near the furnace. 
The cables are out of the reach of possible vandalism and out of site which helps with the aesthetics.

Hope this helps
73  WB2EOD   


Title: RE: Coax entry into basement shack
Post by: K9KJM on December 21, 2010, 10:33:27 PM
My antenna system is based on a Glen Martin 9 foot roof mounted tower. 
The coax and control cables run from the tower, along the roof to the edge where they enter the attic through the gable vent.  From there, the cables run alongside the chimney which terminates in the basement near the furnace. 
The cables are out of the reach of possible vandalism and out of site which helps with the aesthetics.

Hope this helps

73  WB2EOD   

Nice if you have lots of vandals in your neighborhood, A nightmare for decent lightning protection.
For lightning/surge protection, The closer to ground level your coax is where it enters the better. At that point, You want to ground the shield to your "Single Point" ground panel, Which should be bonded with your other grounds.


Title: RE: Coax entry into basement shack
Post by: VE3ELL on December 23, 2010, 06:33:41 PM
I used 4 inch plumbers pipe.Before I finished the basement I installed the pipe with a plastic conduit box on the outside of the house to route the coax thru.The pipe drops down to the floor in the basement.This is large enough to easily pull any size coax thru.Our house has an above ground basement which made this an easy task.I enclosed the pipe in the wall when I finished the basement.If you are getting a new house built you could ask the builder to install such a pipe that can be used for routing coax thru.You can run plastic conduit from the junction box outside to your antenna site for added pest protection from squirrels etc.

                                                    73 Russ   VE3ELL


Title: RE: Coax entry into basement shack
Post by: AA4HA on December 24, 2010, 08:20:11 PM
I had to get a bunch of Heliax installed into a tunnel system 26 feet down under a waste-water treatment plant (around a half a dozen sites). The walls were around 18" thick at the stairwells and had enter a Class 1, Div 2 environment. We used a rotary hammer to make a hole in the wall and used a 24" long, stainless steel pipe, threaded on each end with a compression gland on each side. I had them grout the pipe into the wall to fill in the void between the pipe and the concrete wall.

The installation looks very nice, the rubber grommet on the compression gland compressed nicely down onto the coax and the setup was more water-resistant than the door that was below where the penetration went through the wall.

This was for a passive antenna system to extend cell phone coverage into the tunnels under the plant. Nothing powered (antenna-coax-antenna) so I did not need to worry about intrinsically safe barriers or the hassle of getting permission to put in powered cellphone repeaters.

The threaded pipe works out really well if it is a straight run through a concrete, brick or block wall. The compression glands will keep water out yet you are still able to loosen them up to replace the coax or control cables).

Tisha Hayes


Title: RE: Coax entry into basement shack
Post by: K1CJS on December 25, 2010, 07:19:48 PM
I used a 4 inch dryer vent that was a solid drop type vent (no louvers) as an outside cover.  A four inch pvc pipe just long enough to go through the wall was cemented onto the back of a deep PVC box that was about 8" square and a few 1" holes was drilled on the bottom of that box for cables to go out into the basement.  That box had a cover that was attached by screws.  The pipe and the box were packed by fibreglass insulation to stop vermin and insect entry and drafts.

When I moved to a new home, I removed the co-ax lines and just left the rest of the installation there.  Nothing was ever said about it.


Title: RE: Coax entry into basement shack
Post by: K9KJM on December 25, 2010, 10:17:01 PM
When I moved to a new home, I removed the co-ax lines and just left the rest of the installation there.  Nothing was ever said about it.

YEP!   One of the big advantages of using a dryer vent system.  When you are finished with it, It is ........ just a dryer vent!  Not looking out of place on a house at all!


Title: RE: Coax entry into basement shack
Post by: K3GM on December 26, 2010, 06:49:02 AM
I had a concrete coring company cut an 8" hole in my poured basement walls.  The resulting job is very clean and neat.  The large diameter hole allows me to place a plate over the hole and mount my Polyphasers on the other side within the core.  I've retained the concrete plug for replacement someday if I move. A photo of the job is available from a post I to a similar question.


Title: RE: Coax entry into basement shack
Post by: KB2FCV on December 26, 2010, 09:06:23 PM
I have two lengths of 1/2" heliax for vhf and also open wire line for hf. For the heliax I used the andrew kit for getting the coax through the wall. I drilled through the wood that is right above the cinder block (shingles on the outside - lower most shingle). It's all sealed up nicely as I followed the instructions. If I ever move, it's easy to remove. I then just seal up the hole and pop a replacement shingle on with no holes (I have spares). To get the open wire line in I used two lengths of pvc pipe spaced at the correct distance. I angled them down slightly to keep any water coming in and stuffed them with sponge to keep the critters out.


Title: RE: Coax entry into basement shack
Post by: K8KAS on December 31, 2010, 05:58:52 AM
A 12 inch piece of 3 inch PVC pipe and a 90 Deg elbo. Drill a 3 inch hole just above the brick foundation in the 2 X 12 wood header. Shove the PVC pipe in and your all set. If you don't have a wad of coax you could go with 2 inch PVC. I have 2 inch at this house and have 3 --- RG213 feeds and a ground strap and perfect fit...Takes about 10 min to install... Denny K8KAS 73


Title: RE: Coax entry into basement shack
Post by: W3LK on December 31, 2010, 08:10:45 AM
A 12 inch piece of 3 inch PVC pipe and a 90 Deg elbo. Drill a 3 inch hole just above the brick foundation in the 2 X 12 wood header. Shove the PVC pipe in and your all set. If you don't have a wad of coax you could go with 2 inch PVC. I have 2 inch at this house and have 3 --- RG213 feeds and a ground strap and perfect fit...Takes about 10 min to install... Denny K8KAS 73

Just a suggestion ...

The radius on a 90 degree L is pretty tight; two 45 degree Ls doubles the radius and is easier on the coax.


Title: RE: Coax entry into basement shack
Post by: KE0NW on January 03, 2011, 07:30:58 PM
In home improvement centers you can usually find elbows with 3 different bend rates: a vent elbow has the sharpest bend, a standard has the normal bend, and a long turn elbow has the most gentle bend and would be the best choice for coax. The only disadvantage is that the long turn elbow will have it's exit farther from the wall.


Title: RE: Coax entry into basement shack
Post by: W3LK on January 04, 2011, 01:14:49 PM
In home improvement centers you can usually find elbows with 3 different bend rates: a vent elbow has the sharpest bend, a standard has the normal bend, and a long turn elbow has the most gentle bend and would be the best choice for coax. The only disadvantage is that the long turn elbow will have it's exit farther from the wall.

Electrical conduit has the "gentlest" bends. As for distance, everything is a tradeoff, but when one is bending/pulling coax, the greater radius makes the job MUCH easier.