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eHam Forums => Antenna Restrictions => Topic started by: N1NI on November 18, 2014, 08:34:58 PM



Title: copper lined rain gutter as dipole?
Post by: N1NI on November 18, 2014, 08:34:58 PM
I"m a very new ham (actually a second time around-er). Want to try all modes to see what I like. We live in an attached brick house with a slate roof and wooden gutters on 3 sides. They need repair and we are getting them lined with 16 oz. copper. The roofer is willing to split them wherever I say and I was thinking of turning it into a dipole. Probably have a total length of about 80 feet, about 30 feet up. I am worried about the effect of water combined with the wooden gutter (I read somewhere it will adverse affect things). And I am unsure how to feed this thing. Ladder line? Remote coupler at roofline? Rig is Kenwood TS 590s. I know these are pretty elementary questions but hope someone can help. Thanks in advance.


Title: RE: copper lined rain gutter as dipole?
Post by: WB6BYU on November 18, 2014, 08:45:39 PM
Probably the simplest thing is to split it in the middle as feed it as a dipole as you proposed.
Main problem would be making sure it doesn't leak at the joint.

I'd run ladder line to a balanced tuner at the rig, at least long enough to make sure the
antenna works well enough for what you want.  If it does then you can consider putting
a remote autotuner at the feedpoint (or nearby under the eaves.)


Is copper-lining a standard method of treating wood rain gutters?  I've never run into them,
and would think that a plastic insert would be cheaper and easier to work with (not to mention
less prone to copper thieves).   It probably isn't worth the expense of the copper just to
use it as an antenna, since you can achieve about the same thing by simply laying a wire
in a non-conductive rain gutter or attaching it to the roof or under the eaves.  But if that
is what you are going to have done anyway and there is no significant added cost, then
give it a try.


Title: RE: copper lined rain gutter as dipole?
Post by: N1NI on November 18, 2014, 09:14:59 PM
Thanks. Keeping the wooden gutters because it is an attached house and needs to match our neighbors. Copper lining will allow it to last another century (important because I am 72 years old and expect to live to be 172). The copper part is my XYL's thing and I am just trying to take advantage of her irrationality about this. Planning to get an LDG KT-100 ATU but it only takes coax so I guess I need a balun, right? 4:1?


Title: RE: copper lined rain gutter as dipole?
Post by: WB2KSP on November 19, 2014, 06:09:55 AM
And how would its resonance change every time it rains or when it fills with leaves.


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 19, 2014, 08:45:29 AM
Why not line it with vinyl instead and place a wire dipole in it at inner outside lip of vinyl gutter insert? using a cooper lined one will be very fussy to tune and greatly effected by water and debris.


Title: RE: copper lined rain gutter as dipole?
Post by: WB2JNA on November 19, 2014, 09:21:26 AM
I agree with the suggestion of making a dipole out of insulated wire and just using the gutter to "support" the wire. I would feed it with ladder line and use a tuner at the radio. That will probably be much less influenced by water and debris in the gutter.
I assume that you can't string a dipole out in the clear and free of the gutter altogether? That would probably be even better. Good luck.


Title: RE: copper lined rain gutter as dipole?
Post by: WB6BYU on November 19, 2014, 10:35:15 AM
The copper does have the advantage of a fatter radiator, so the impedance changes
less with frequency.  With enough copper that may reduce the detuning effects of
water and debris, but if you are using it with a tuner anyway you can tweak it as
needed, so that shouldn't be a problem.

If you use a balun it should be a 1 : 1 current balun because the impedance
will vary over a wide range with frequency.  This applies whether the tuner is at
the feedpoint or in the shack.


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 19, 2014, 01:48:50 PM
The copper does have the advantage of a fatter radiator, so the impedance changes
less with frequency.  With enough copper that may reduce the detuning effects of
water and debris, but if you are using it with a tuner anyway you can tweak it as
needed, so that shouldn't be a problem.

If you use a balun it should be a 1 : 1 current balun because the impedance
will vary over a wide range with frequency.  This applies whether the tuner is at
the feedpoint or in the shack.

Inside a wood gutter that itself will vary in moisture content and water in gutter would make it very unstable. A wire hidden in lip of a vinyl insert would be free of debris and water detuning it. 


Title: RE: copper lined rain gutter as dipole?
Post by: N1NI on November 19, 2014, 02:13:22 PM
Hmm. Lots to think about. XYL wants the copper, so I guess I do too (that's how I've stayed married for 42 years). The comments so far make sense (even the ones that disagree with each other). I might try radiating from the copper and if that doesn't work lay an insulated wire in the gutter. I don't have good supports on the property for a wire dipole (townhouse in a densely populated city with very little land front or back and no trees of my own). There will be a lot of copper in the gutter (probably about 5 inches formed to fit into the gutter) and also some connected flat sheets of copper over the doors to prevent icicles (about 2 feet by 4 feet), so that's kind of a wild card. I will use an ATU at the station end. Thanks for the balun info.


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 19, 2014, 05:10:46 PM
It will not do any good to lay a insulated wire in a copper gutter. With price of copper I would not line gutter with it where you cannot even see it.


Title: RE: copper lined rain gutter as dipole?
Post by: KK4GGL on November 19, 2014, 06:46:08 PM
Hmm. Lots to think about. XYL wants the copper, so I guess I do too (that's how I've stayed married for 42 years). The comments so far make sense (even the ones that disagree with each other). I might try radiating from the copper and if that doesn't work lay an insulated wire in the gutter. I don't have good supports on the property for a wire dipole (townhouse in a densely populated city with very little land front or back and no trees of my own). There will be a lot of copper in the gutter (probably about 5 inches formed to fit into the gutter) and also some connected flat sheets of copper over the doors to prevent icicles (about 2 feet by 4 feet), so that's kind of a wild card. I will use an ATU at the station end. Thanks for the balun info.

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?

If you have shingles, you might consider inserting a thin wire underneath the shingles. You could make a dipole or a full loop that way.


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 20, 2014, 04:47:22 AM

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?


If gutter is copper lined this is pointless.


Title: RE: copper lined rain gutter as dipole?
Post by: KK4GGL on November 20, 2014, 08:42:01 AM

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?


If gutter is copper lined this is pointless.

So says the self anointed expert on everything.


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 20, 2014, 08:57:04 AM

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?


If gutter is copper lined this is pointless.

So says the self anointed expert on everything.

Another clueless troll.


Title: RE: copper lined rain gutter as dipole?
Post by: KK4GGL on November 20, 2014, 11:23:29 AM

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?


If gutter is copper lined this is pointless.

So says the self anointed expert on everything.

Another clueless troll.

AHAH ahah HAhah HAH ahhahah HA ha aha ha...

Oh, you were serious?

AHAH ahah HAhah HAH ahhahah HA ha aha ha...


Title: RE: copper lined rain gutter as dipole?
Post by: WA2ISE on November 21, 2014, 01:55:08 PM

Is it possible for you to tack/staple  thin wire to the top edge of the gutter?


If gutter is copper lined this is pointless.

How about connecting that wire to the ends of the copper lining, creating a folded dipole? Then accumulated leaves and water won't have that much impact (the debris will just act like birds on a wire, not shorting anything out). 


Title: RE: copper lined rain gutter as dipole?
Post by: N1NI on November 24, 2014, 04:03:44 PM
Interesting idea (folded dipole). Is it less sensitive to surrounding environmental conditions (ice, snow, leaves, moisture)?


Title: RE: copper lined rain gutter as dipole?
Post by: W8JX on November 24, 2014, 05:10:24 PM
Interesting idea (folded dipole). Is it less sensitive to surrounding environmental conditions (ice, snow, leaves, moisture)?

No more than a dipole but they do tend to be a bit quieter.


Title: RE: copper lined rain gutter as dipole?
Post by: VE3PP on December 01, 2014, 04:13:18 AM
42 years of marriage, well you are doing something right (coming from a guy who has been married 32 years)

However I do not understand your wife's logic of wanting copper lining in those wood gutters. No one is going to see the copper lining so why go to that expense? (It has to be costly to form that copper lining into the gutter, along with the expense of the copper)

Personally I would line them with vinyl and then use wire for the antenna as others have suggested. By doing that you will not have a joint in the lining as you will if you split the copper lining. And vinyl is going to outlast you (I hope you make it to 172 but ................... ;D)

Good luck either way you go.


Title: RE: copper lined rain gutter as dipole?
Post by: KE4TSP on February 03, 2015, 05:16:40 PM
I see this is an old post, but I'll run the risk of being battered by the bastions of eham propriety. Most all gutters hold 1/4"-1/2" of water in them until it evaporates out, it doesn't all drain out through the downspouts. It would seem to me that the "dipole" would become a single conductor when standing/running water bridges the gap between the two sections of copper lining....

Fire away!