Ladder line through house...

[KB1OJU]

is it safe to route ladder line from the outdoors, into your house?

for me, it will go from the antenna into my basement, and routed from the basement, into the shack.

is it safe to do this? or will swr's get all screwed up? im just looking for a way to get rid of line loss! and help is welcomed


thanks to all!!!

73

[k0dxc]

I don't think that the SWR would get to messed up unless you are running by some metal objects in the house, but saftey wise, from what I have heard about ladder line i'm not to sure it's a good idea. Are there any other family members in the house besides you?

[KB1OJU]

yes, there are other family members in the house, im the youngest in a family of 4, im 16, so yeah, im running the ladder line ALL THE WAY from one end of the house, to mine, so yeah, it could be a little bit leaky of an rf system, but im not to sure, i dont know much about ladder line, just where to hook it up ;)

[k3wrv]

I Run mine from the dipole on the roof to the basement, all the way across the basement, and then down to the rig. It's within a few inches of a heating duct, and works well. RF measurements in the shack show much lower than on the RG-213 running to my beam. You'll probably want to space it (IIRC) about twice the conductor spacing away from most metal objects, or try to cross them at a 90 deg angle.

[EDIT] I have no idea what the SWR from the line to the antenna is, but it can't be good... 160 M EDZ fed on all bands. But the Johnson Matchbox(tm) keeps the rig happy.

de Bob

[KB1OJU]

yeah, good point k3wrv, i think ill do that, im thinking about doing it tonight, but eh, im to lazy :) haha, but thanks for the help


anymore suggestions?

[ve2nsm]

Theoratically a well designed and installed balanced line radiates less RF than even a good coax on a less than perfect antenna.

[N2RJ]

I had ladder line in here, no problems radiating RF into the shack at all.

Probably going to put some back for a dipole or other antennas for the lower bands.

[AG3Y]

Truly balanced ladder or open wire feedline does NOT radiate, as the currents are equal in strength and exactly out of phase. Keeping those currents equal and out of phase is the tricky part. In theory, separating the line twice the conductor spacing away from metallic objects should keep unbalance problems to a minimum, but it doesn't hurt to try to keep it further away than that! The biggest problem you might run in to is running parallel to household wiring inside the wall. You might not have any idea where that wiring is, and it could be closer to the ladder line than you might think !

Don't get hung up on SWR ( standing wave ratio, NOT ratioS ! ) There is WAAAY too much emphasis placed on that, more than likely because of the combined wisdom of users of another radio service!

73, Jim

[N0NB]

In years past I had the ladder come into the window. go up and over my desk and back down to the tuner.

There's nothing wrong with me... Bzzztt! Urrrp!!! Gasp!

[K8MHZ]

Beside the provisions listed here:

http://ecmweb.com/nec/electric_article_radio_television

You will find that antenna discharge units are required by the NEC for any lead-in from an amateur transmitting station's outdoor antenna unless it is protected by an effectively grounded continuous metallic shield, (As in coax), or where the antenna is permanently and effectively grounded. (balanced antennas, such as dipoles, are not) (810.57)

Also, in an amateur transmitting station, except where protected by an effectively grounded continuous metallic shield, lead-in conductors entering a building must be protected by either (1) a rigid, noncombustible, nonabsorbent insulating tube or bushing, (2) through an opening provided for the purpose in which the entrance conductors are firmly secured so as to provide a clearance of at least 2 inches, or (3) through a drilled window pane. (810.55)

With the exception of coax with a grounded shield, 3 inch stand-offs are also required. (810.54)

[ae5bn]

I ran mine in through a hole in a board in the window.

[wy6k]

I run 450 ohm insulated twin lead into the shack by opening the window and slipping it thru the gap and then closing the window on it. It then runs willy nilly across a couple of metal work benches, on top of some test gear, along the floor over a bunch of power cords and coax and up to the antenna tuner. I run the full legal limit with no problems. I do have RF in the shack (lousy ground since I'm on the second floor) but no more with the twin lead than with the coax-fed antennas. I don't have any kids around.

[NA4BH]

I have my 450 ohm line run through the gable over my garage into my little room. I get a very small amount of RF when I kick in the AL80B @ about 1KW. Other than that, no problem.

I will be able to type better after the catarac surgery. :D :D :D JUST KIDDING!!! :D

[AA0CX]

I'd like to try some ladderline.

[KB2FCV]

One installation I have seen was a friend of mine who replaced the glass basement window with plexiglass. He drilled through that two holes with threaded rod and ceramic insulators on both sides. The open wire line connects to this. This makes for a nice disconnect point for storms or if you need to open the window for any reason. On the inside he has an unfinished basement and has spacers dropping down from the beams a few inches. These spacers support the feedline. There are also spacers on the wall and the feedline ends at his tuner - very nice!

[WA7KKP]

Hams were doing this since the 20's and 30's. Before coaxial cable was invented.

Gary WA7KKP

[KD8HMO]

Wouldnt using 50 ohm coaxial cable with a balun be better than twin lead or ladder line?

[N0NB]

Wouldnt using 50 ohm coaxial cable with a balun be better than twin lead or ladder line?

No.

Much has been written on this topic that I won't rehash here. Google is your friend. :D

[ae5bn]

Wouldnt using 50 ohm coaxial cable with a balun be better than twin lead or ladder line?

Not for a Low Loss Multi-band antenna.