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eHam Forums => Station Building => Topic started by: KT4DLB on February 07, 2013, 09:00:14 AM



Title: Window Feed Thru
Post by: KT4DLB on February 07, 2013, 09:00:14 AM
I'm looking at using a MFJ-4601 Window Feed Thru panel on my station and will run about a 10' jumper to the radio and the ground will be about that look to, Is there anything special I need to do to be safe?

73  Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: KQ6Q on February 07, 2013, 12:41:04 PM
The 4601 should get the job done nicely. On the outside, you might want to ensure that you leave 'drip loops' in the coax that connects to the outside of the panel, so you don't get water running down the coax onto the connectors.


Title: RE: Window Feed Thru
Post by: WB2WIK on February 07, 2013, 05:41:50 PM
On the outside, ground the panel to your household electrical service entrance ground using at least #6 AWG copper wire.


Title: RE: Window Feed Thru
Post by: KT4DLB on February 08, 2013, 02:53:31 AM
I don't think I can do that. The ground for the radio will be on one end of the house and the house ground for the electric coming into the house is on the other end. I was planning on putting a 8 foot ground rod by the window and ground my radio and other equipment to that. Won't that work like that?


Lamar


Title: RE: Window Feed Thru
Post by: K1CJS on February 08, 2013, 04:34:26 AM
I don't think I can do that. The ground for the radio will be on one end of the house and the house ground for the electric coming into the house is on the other end. I was planning on putting a 8 foot ground rod by the window and ground my radio and other equipment to that. Won't that work like that?

Yes, it would work...as a ground.  It would also prove to be dangerous, in the way that if there is any potential voltage difference between the two ground rods, you or anybody who touches your equipment may become the connection through which that potential is equalized.  In other words, you may receive an electrical shock that may kill you!

If you do install another ground rod, the National Electrical Code requires that the two ground rods be connected--bonded--together with number six cable.  That is to prevent your survivor from appending 'SK' to your callsign.


Title: RE: Window Feed Thru
Post by: KT4DLB on February 09, 2013, 03:08:00 PM
If I understand right, I need to run number six  cable ground wire  around to the electrical ground. Can I bury the ground cable or do I need to attach it to bottom of house at ground level or up under the eves of the house. I want to make sure that its do proper and no mistakes.

73 Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: K1CJS on February 09, 2013, 04:20:59 PM
It should be at or below ground level.  You don't want it attached to combustible materials anywhere as a precaution.  Also, keeping it direct, short as possible and without any sharp bends in it is best.  At house corners, approach the corner with the cable out away from the foundation so you can do that.  You can either bury it or leave it laying on the ground if there isn't any possibility of someone or something snagging it and displacing it, but I would bury it, even if only a couple of inches deep.  Keep clamped connection above ground to conform with the Nat'l Elec. Code.


Title: RE: Window Feed Thru
Post by: KT4DLB on February 09, 2013, 08:22:55 PM
Thanks. I will bury it then. I want to make sure that I do everything right and safely also.

73  Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: KT4DLB on February 10, 2013, 08:12:33 AM
One more question, does the ground wire need to have a cover or can it be bare? Just roughly measuring, I will have to run the wire about 100' to the main electrical ground. Also the ground wire will cross a live electric wire that is buried running to an outside storage building. Will that cause a problem there?


Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: KT4DLB on February 10, 2013, 10:20:01 AM
One more question, could I ground it to a water pipe that comes out of the house? If I could use it, the distance would only be about 25 foot.

Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: K1CJS on February 11, 2013, 05:15:02 AM
The ground wire can be a bare wire if that is what you have.  It does not need to be covered.

To the water piping--check to make sure the entire water system is copper pipe before you connect to it.  Also, some localities have codes that prohibit it if the water system uses plastic (PVC) piping anywhere in it.  

If it is all metallic and local codes do not prohibit it, yes, you can use it.  The idea here is to connect and equalize ground rod potential, not to use the piping to conduct a lightning charge.

Added--BTW, sorry for the delay.  I'm located on Massachusetts' south coast, in the middle of the recent snowstorm and was without power for a day.  73!  


Title: RE: Window Feed Thru
Post by: KT4DLB on February 11, 2013, 09:12:41 AM
Thanks to everyone for all the information. I have found EHam.net a very great site for information from experience ham operators to us newbie's that are starting out. Thanks again!

73 Lamar
KK4NZO


Title: RE: Window Feed Thru
Post by: AA4HA on February 12, 2013, 01:49:59 PM
A bare buried bonding conductor will also improve the general performance of your grounding system as there is more bare metal in contact with earth.


Title: RE: Window Feed Thru
Post by: N2OAM on February 25, 2013, 07:57:59 AM
          You REALLY need to connect your station ground to to the service entrance ground.  A nearby lightning strike can create a large potential difference between the 2 ground systems.  VERY bad Ju-Ju for the equipment in your house.

73 de bob,
N2OAM


Title: RE: Window Feed Thru
Post by: KF7ZCH on March 25, 2013, 07:38:51 PM
If my radio may be in the inside of the house next to no outside walls, would it be bad to run the ground inside the walls and out the house.  I would possibly do the same for the coax as well.  Both the coax and the ground wire could come across electrical lines in the house.


Title: RE: Window Feed Thru
Post by: N0IU on March 26, 2013, 05:15:32 AM
You have probably already completed your project, but just in case...

I made a window pass-through using a vinyl covered MDF board from my local "bog box" home improvement warehouse. I bought galvanized fender washers big enough for both sides of the UHF bulkhead connectors.

The 4601 cost $60 and I built mine for less than $20 and it does the exact same thing.


Title: RE: Window Feed Thru
Post by: KG4RUL on March 26, 2013, 05:30:03 AM
The BIGGEST safety issue with this setup is the fact that it can be pushed out of the window relatively easily.  Just perfect for the local Meth-Head to get easy access to your home.


Title: RE: Window Feed Thru
Post by: N0IU on March 26, 2013, 08:40:00 AM
The BIGGEST safety issue with this setup is the fact that it can be pushed out of the window relatively easily.  Just perfect for the local Meth-Head to get easy access to your home.
Not that I am particularly worried about my local meth-heads breaking in but more for keeping the WX outside....

I cut two pieces of wood slightly longer than the distance from the top of the window to the top of the channel and whacked them in place on each side of the window channels creating a very tight seal.

And if one of my local meth-heads still manages to get in, I have a 12ga shotgun next to the bed for such an occurrence!


Title: RE: Window Feed Thru
Post by: AB3RY on April 24, 2013, 12:40:41 PM
At the risk of raising a dead thread, I have a followup question.  Like the gentleman starting this thread, I am a new ham starting out.  

I have a 2m/70cm vertical with an MFJ window panel and G5RV on the way.  My plan is to ground the antennas and the window panel outside the window with a ground rod and then run a cable around to the other side of the house connecting the antenna/station ground to the electrical service ground.  Is this the right solution?  

Alternatively, the house is old and has BX wiring (flexible steel conduit) and good ground everywhere, can trying into this ground suffice for connecting to the electrical ground? 

If I add another vertical or tower I would ground that at it's location and it's feedline would be grounded at the station entrance, yes?

Thanks.


Title: RE: Window Feed Thru
Post by: K1CJS on April 24, 2013, 03:33:45 PM
...I have a 2m/70cm vertical with an MFJ window panel and G5RV on the way.  My plan is to ground the antennas and the window panel outside the window with a ground rod and then run a cable around to the other side of the house connecting the antenna/station ground to the electrical service ground.  Is this the right solution?

You're good so far... 

Quote
Alternatively, the house is old and has BX wiring (flexible steel conduit) and good ground everywhere, can trying into this ground suffice for connecting to the electrical ground?

No, best not to do this.  Keep your equipment ground separate and tie the station ground to the electrical ground at one place.  Doing otherwise can lead to having ground loops which can be problematical to your station. 

Quote
If I add another vertical or tower I would ground that at it's location and it's feedline would be grounded at the station entrance, yes?

If you put a ground rod at the tower or at the vertical, you'll also need to bond that ground rod to the other two, usually at the station ground outside the window.  73 and good luck!


Title: RE: Window Feed Thru
Post by: W1JKA on April 25, 2013, 01:41:57 PM
 No special window feed through needed if you use the COMET flat coax, you can close your window on it but only rated for 100 watts.


Title: RE: Window Feed Thru
Post by: N9JKU on May 23, 2013, 09:15:52 AM
I hope this thread isn't too old to bring up.

I would like to place my shack in a second story bonus room. No matter what its on the second story, unfortunately. My electrical box/ground is going to be on the back side of the house, and the rig would be on the front. My plan was to run it through a pass-thru 5 feet from the built in desk I want to use. From here, my feedline would go to a G5RV streched NW-SE across the roof of the house, probably clearing it by a few feet. I would ground below the window, with two bends coming through the wire due to a driveway being right underneath the window. I would have a station ground at this corner, and run a connecting wire with one bend to the service ground behind the house. Also, I would place a random wire in the attic, and a 2/440 clotheshanger, in the attic too.

I don't quite understand all of the concepts of grounding, I know I need the grounds connected, and when there is a bend in the wire to have as shallow of an angle as possible. To that extent, for the connection wire, I plan on using thick, bare, copper wire buried 12 inches about 5-8 feet outside the perimiter of the house, to alllow for the shallow turn.

Am I forgetting anything in this set up? Would I be better off relocating to a room on the backside of the house, closer to the service ground? In that situation I could also bury multiple ground rods in the back yard, something I wouldn't be able to to on the front side due to property lines. The only issue on the back side of the house, is I would need to figure out a diffrent way to hang a dipole due to the electric drop line entering close by.