New antenna just arrived today...

[TiredCat]

It was a couple of weeks ago that I put one of my two scanners back into service, after a long stent in the dark recesses of the closet in my radio room. The other scanner, I'll get up and running very soon I hope.....I'm tryin to get the hang of using ProScan software with it (struggling there...for now anyway). Anyway, I never really had what I would consider to be a real antenna system in use with my scanners. What I have in use actually works well....but I'm after much better. I have enjoyed listening to my scanner so much over the past couple of weeks, that I decided I would approach this "interest" with more seriousness than I had in the past. So I ordered a Diamond D130NJ Discone antenna from DX Engineering.....it just arrived today. My plans are to get that antenna up about 40', and feed it with some LMR 400 Flex. I'm pretty anxious to get it all up and going.....just waiting on a day that I have the time. Just thought I would share......I'll let ya know how it works once it's up!

 

[CanesFan95]

40 feet is a good amount of height. Heighth is king when it comes to antennas. So what are you mounting it on? A tower?

 

[TiredCat]

No tower. I have a tower, but that is for a beam antenna and nothing else. I will mount the Discone to a home-brew antenna mast. I have made them for years out of 10 ft sections of galvanized metal conduit. They are very strong and easy to build. The way that I do them, they require no guy wires that stretch all over the place for support. I have a 6 meter loop antenna atop one of them now and am using another as a center support for a 40-20 meter parallel (fan) dipole. The center balun hangs from a pulley system at the top of the mast, which is right at 40 feet. I have had multiple antennas mounted on these home made mast poles. But....40 feet is max hight with this type of mast. Any higher and bad things can happen............I know from experience.

 

[K4EET]

No tower. I have a tower, but that is for a beam antenna and nothing else. I will mount the Discone to a home-brew antenna mast. I have made them for years out of 10 ft sections of galvanized metal conduit. They are very strong and easy to build. The way that I do them, they require no guy wires that stretch all over the place for support. I have a 6 meter loop antenna atop one of them now and am using another as a center support for a 40-20 meter parallel (fan) dipole. The center balun hangs from a pulley system at the top of the mast, which is right at 40 feet. I have had multiple antennas mounted on these home made mast poles. But....40 feet is max hight with this type of mast. Any higher and bad things can happen............I know from experience.

Hi @TiredCat, would you mind sharing what diameter and wall thickness those 10 foot sections of galvanized metal conduit are that you use? Also, how do you join the sections together? Finally, how do you construct the base? At 40 feet self-supporting with a Diamond D130NJ Discone antenna on top, LMR400 up the side and 50 MPH wind gusts; that would be a LOT of angular turning moment at the base if the sectional joints hold. And if you live in an area subject to ice storms …

I’m asking because we have a lot of DIY folks here and if you have a good 👍 plan, please share it.

I for one have used an uncut 20 foot piece of fence post (galvanized pipe) to support a 22 element 2 Meter beam (two 11 element beams phased). But that was supported by house brackets in the middle and at top. It was not self-supporting. At the bottom, I had a drain system for any moisture/condensation that happened to be inside the pipe. The downward moment was mostly handled by the house brackets with 3-point mounting that was welded per my specifications. My design was overkill but better to be safe than sorry when lives and property are at risk. This was on a ranch style house that I no longer own.

 

[PDXh0b0]

I welded the legs from one of my shelves like this haha centered a pvc pipe in a 5 gal bucket and filled it with quickrite for the base, clamped to the apex of the roof. it sways when the wind kicks up, lol, but it's been thru some stiff wind storms.

Hi @TiredCat, would you mind sharing what diameter and wall thickness those 10 foot sections of galvanized metal conduit are that you use? Also, how do you join the sections together? Finally, how do you construct the base? At 40 feet self-supporting with a Diamond D130NJ Discone antenna on top, LMR400 up the side and 50 MPH wind gusts; that would be a LOT of angular turning moment at the base if the sectional joints hold. And if you live in an area subject to ice storms …

I’m asking because we have a lot of DIY folks here and if you have a good 👍 plan, please share it.

I for one have used an uncut 20 foot piece of fence post (galvanized pipe) to support a 22 element 2 Meter beam (two 11 element beams phased). But that was supported by house brackets in the middle and at top. It was not self-supporting. At the bottom, I had a drain system for any moisture/condensation that happened to be inside the pipe. The downward moment was mostly handled by the house brackets with 3-point mounting that was welded per my specifications. My design was overkill but better to be safe than sorry when lives and property are at risk. This was on a ranch style house that I no longer own.

 

[K4EET]

I welded the legs from one of my shelves like this haha centered a pvc pipe in a 5 gal bucket and filled it with quickrite for the base, clamped to the apex of the roof. it sways when the wind kicks up, lol, but it's been thru some stiff wind storms.

I have to admit, that is some impressive welding and I can only imagine it swaying "when the wind kicks up" - wow!

 

[CanesFan95]

I do see masts from time to time that look way too high above the lowest supported point. So you'll see a mast with like 20 feet dangling above the mounting bracket at the edge of a roof. I hate seeing that.

 

[TiredCat]

I tried to post a reply to some questions about my home made mast poles last night and something was wrong with the forum I guess. I could never get it to post. So....I'll try to explain this again! It is really stupid simple. I'm just the kind of person that will try and build something rather than buying it if possible. I even enjoy building my own antennas very much. Anyway....I buy 10' sections of galvanized metal conduit pipe from the Lowes near my house. I would have to go outside and measure to be exact. But, what I'll do is buy, let's say, a 10' section that is 2" in diameter, another that is 1.75" diameter, another 1.5", etc. You get the picture. I will in order of descending diameter slide one pipe into the other. But, only far enough into the larger diameter pipe to insure that this joint area will NOT be a weak point. I then cross drill through the two sections and bolt them together with bolts, nuts and washers of course. Once the mast is put together, then comes the part that supports it. Also the part that some people may not want to do.....but it works! I will take a post hole digger and dig a very nice clean hole and place a 4X4 wooden post in it. I'll get it perfectly straight and level and then mix and pour Qick-Crete in the hole. Thus cementing the 4x4 in the ground. I'll leave maybe 5-6 feet above ground. Once that is dried I place the base of the mast that I built against the base of the 4x4 and slowly walk the mast up. Once its erected and against the support post, I actually will fasten it to the post with three ratchet straps good and tight. The straps being well spaced from the bottom to the top of the post. I live in Alabama and we regularly have severe thunder storms with high wind and worse. I have had these masts up with antennas on them for years and they sway to and fro.....but never have they ever bent or broken from wind. Now keep in mind. They are not suitable for large antennas with weight or high wind load. I have used them without incident with verticals, small loops, ridged dipoles and supports for large HF dipoles that stretch quite far across my yard. The actual height that I normally get out of these is usually just shy of the 40' mark. They are closer to 35ish' (give or take) once said and done......this I have found to work the best. Any longer and there may be issues where the sheer weight of the mast could bend while erecting it. But it's a simple way to get an antenna up at a descent height without having guy wires stretched all over the place!! And it is VERY durable!!!
I'm gonna try and post a couple of pics......if I can!


Above is a 6 meter loop on one of the masts. This one is right around 36-37'.



Same 6 meter loop. If you look close you can see where I bolted sections together.



Above is not the greatest pic. But, it is a center support for a 40 and 20 meter parallel (fan) dipole. This is where the balun hangs. The antenna is not up here, I had it down for a bit of maintenance I believe. This whole antenna system is on pulleys so that I can raise and lower easily. You can see the top of the 4x4.
I hope this helps explain......nothing elaborate! But it does the job quite well!!
I hope to eventually get my new Diamond discone antenna up on one of these and get my BCD996XT hooked to it!!
Thanks a bunch fellas!

 

[CanesFan95]

I still think that's an awfully tall piece of metal dangling around up there unsupported.

 

[jonwienke]

Without guy wires, it probably won't survive a windstorm. 30+ feet is a lot of leverage on 2" conduit, and I doubt it will survive on its own.

 

[TiredCat]

I'm not speculating that these home-brew mast poles will work well. Nor am I trying something new or outside the box to get a discone up in the air. I'm just stating a fact that they not only work, but work very well (with no guy wires). No speculating....LOL.
Of the three that I have up now, two have been up every bit of 4-5 years with no hiccup or need to take down. The pole and the antennas sitting on top of them in fine shape. There's been quite a few severe weather events with pretty high winds roll through this part of north Alabama over the past few years I can assure you. Anyway......just sharing my answer to the eternal question asked of all true radio enthusiasts everywhere....How can I get this antenna up there!!!????

 

[merlin]

You are talking a home brew Channel Master 40' pushup mast. these have guy tabs at every 10' section for a damned good reason. So you are in tornado alley, 40' up with no guys. A discone on top, that mast will be a pretzel over 50 MPH wind.
My discone is 5.5' above roofline on 3, 18 gauge 5 ' sections. Lag bolts to framework with heavy duty wall brackets. In 50 MPH wind I worry about it folding.

Perhaps some professional specs in order:

 

[SteveSimpkin]

I did something similar about 10 years ago. I bought three sections of 1-3/8 in x 10 ft. 6 in. 17-Gauge Galvanized Top Rail from Home Depot. These are tapered at one end so they lock together. I wet the ground below the apex of the roof on our single story home. I then used a fence post hammer to drive it about 5 ft into the ground. I attached the next 10 ft section to it which brought to top just above the apex of the roof. I used a eave mount bracket to attach to pole to the roof apex. I then mounted a 2M/440 J-Pole antenna and coax to the top of the third section and slid it over the two stacked poles. This gave me a J-Pole antenna on top of a 25 ft mast with no guy wires. It has withstood many 60 MPH+ windstorms over the years and still works great.