short tower vs higher tower and LONG ladder line

[Catbrain]

I am just beginning into ham radio. just got a Kenwood 830s. (my old school dream radio). It was restored before i got it.
Have to collect some more accessorie goodies yet- like matcher-tuner, external speaker- maybe a comet analyzer. ect.

My house has a steep hill right beside it that blocks the south-east direction. Can't even get broadcast radio stations.
However the hill is about 75-100 feet tall. From up there i can see the horizon for 360 degrees. So from a line-of-sight standpoint -- it could be great. A neighbor gave me 4 sections of a bottom hinged tower. So it could be 40 feet plus a pipe up top - maybe 8-10 feet more. i see that open wire ladder line looks like the way to go for longer coax runs. if I try to put the tower up on top of the hill--- it looks like I will have about 300-400 feet to the feed point to run the ladder line. i have yet to measure the distance with my rangefinder.

My question is-- is that long a run - with open 4 inch ladder line-- will there be enough loss to nullify the effort of getting the antenna above the local terrain ? Should I try to find an on-line loss calculator for ladder line and try to put a number on the losses ?

also---i got a couple rolls of insulated # 20 solid copper. (door bell wire) Do I need to go fatter conductor for a long run ?
I see some people are using # 16 for their ladder line. is there enough current that # 20 will be making significant losses ?
do I need to go to 18 or 16 for 4 inch ladder line ? ( I expect sometime later- down the road- to try an amplifier---if I can afford one or build one from scratch--- so there could be more current and voltage later on--)
I expect to start out with a resonant dipole for 80, 40, 20 meters ect---

Thanks ahead of time for any thoughts. Im just starting in this so I am trying to be a sponge. for knowledge.

 

[MUTNAV]

I thought someone would reply by now...
Just some thoughts....
20 ga seems too thin for what you want, personally I would go with 16 Ga or thicker.

I think it will be well worth the effort to get your antenna where you want it.

There are other factors to consider. The first being the weight of the cable.... it's going to have to be supported periodically on the way up,

the other thing to consider is lightning and static. PLEASE do a good lightning protection system.

That is a big deal with a tower on top of a hill. It's important to be aware that even blowing winds will introduce voltage into your radio.

I'm terrible at something called mission creep. If I had a tower on top of a hill with 360 degree views, I would also put in the wiring for a rotatable camera.

As well as control cables for possibly a different type of antenna on the tower (shared apex loop antenna maybe).

Please let us know how it works out. It sounds like a major task, with potentially GREAT returns.

Can I ask where you are at (general part of the country)?

Thanks
Joel

 

[Catbrain]

Yes Joel--- lots of views but not much advice.
I too like the idea of a camera up there. Maybe wireless powered by solar.

The hill kind of blocks my northern horizon. West is good and southwest ok from house.
The hill rises up about 100-150 feet up in about 100 yards horizontally. Thee is one more hill about 75 feet
further up-- but thats another 200 yds away. Too long for feed line. but I think I can make it up to the first hump with about 275 feet of feed line. i might try the 20 Ga wire first because I will be in receive only mode for a little while. When transmitting happens I will re-do with larger wire. ( Im studying for the tech license now-- and listening. )

one problem--- is how to ground the base of the tower. The hill has much shale. Up on the top there are dense trees--- so Im not sure how far I can get ground rods down. Have to look up and see how far down they need to be. They might go down 2 feet and hit the shale. (?)

I have 4 tower sections -- the bottom one is hinged. There are LOTS of trees up there to hook my coffin hoist to for pulling it up. I expect to pour a little concrete pad to anchor the base into so it cant slip when it is time to pull on it. Not sure if I will use 2 sections or 3 or all 4. Top section has a socket for a pipe. So I might get another 8 feet or 10 from that. Thought I'd rig it like a flagpole. Hook the center of the dipole to the rope and hoist it up. Make a thimble and socket that will mate when it is fully up to prevent too much movement from the wind. May have to cut a few trees to make a limb free corridor for the two limbs of the dipole. Don't know which direction would be best to point it..... I am in North East TN. about 30 min due south of Kingsport.

I still have to collect some more radio parts --- like a tuner--- and a nice desk mike. Why the heck are amplifiers soooo expensive ? Am I going to have to build one from scratch ????
i may have to buy a comet antenna analyzer before its all done -- looks like it could be an indispensable tool. Don't know any other effective way to measure the impedance of the antenna and the line.

im just beginning -- so I an on the steep part of the learning curve. i want to get to general because that seems to be where the fun part happens.

Tim

pS thought I would rig a insulated support post about every 50 feet or so to help keep the weight off the line---and to prevent it swaying into a tree limb somewhere down its journey to the tower.

I have to sandblast and do a repair or two on the tower and paint it with aluminum paint - several coats.
its an older tower- so I don't intend on ever climbing it. thats why I'm making it like a flag pole. I will tip it down before i will climb it. (maybe)

 

[prcguy]

I have a place in the mountains that is a couple hundred feet below the mountain ridge above me. The whole area is surrounded by high mountains and on VHF or UHF I can't get to any repeater outside the valley, it just doesn't work. For HF I have a 64ft 40-10m horizontal wire EFHW 20ft above ground and a Shakespeare 1/2 wave vertical for CB/10m. On HF 40-10m I can hear and talk to anyone anywhere, same as my home in the somewhat flat lands. On CB/10m I can hear skip coming from all directions, even the direction straight into the side of the mountain.

I would first try HF at your house with a horizontal antenna maybe 20-30ft off the ground, you might be surprised that it talks all over the place. That will give you good NVIS on 80, 60 and 40m, the bands where NVIS works then the antenna can work well on all the higher bands depending on make and model.

 

[Catbrain]

right now I am in receive only mode. ( a kenwood TS830s) I hung a home made dipole over the 2-nd story balcony just to have something to listen to.
each leg about 8.4 feet long. ( no TX till later) The balcony wasn't long enough for much more. Its boadside to east-west.
i have heard Sal in Tampa most nights really loud. Heard him talking to bob in Ontario. I think that was on 7 mhz. i don't know if that's an artifact of my antenna (I doubt it) or Sal's 1500 W.
in the early evening a few nights ago I heard england, germany, italy , Norway and Oregon and several in Canada and conneticut. Could hear about 5 different groups doing check-ins -- on in Delaware. Not really loud but very readable. The more I listen- the more I like listening.

The hill seems just too good to pass up.

Do yall know how to get ground rods in around the tower base if there is a lot of rock underneath the soil ?
( cordless hammer drill ????? )

Is your CB antenna one of those 8 foot stainless steel whips I used to see on everybody's pickups back in the 80's ? Have you tried tuning that for the longer wavelength bands to see if would match ?

 

[MUTNAV]

Even though I think it would help to get the antenna up high, prcguy's ideas about NVIS have a lot of merit, great regional coverage and it would limit noise from non-regional sources. I'm surprised you can get the great coverage you do... Good for you...

As far as the near surface shale,

https://wbdg.org/FFC/NAVFAC/DMMHNAV/hdbk419a_vol2.pdf

Page 1-8 addresses it...

The handbook also addresses some grounding questions that I think you posted on other threads

It's kind of long, but (possibly) worth it.


Volume 1 is

https://wbdg.org/FFC/NAVFAC/DMMHNAV/hdbk419a_vol1.pdf

I hope this helps.... (at least its a lot of good reading).

Thanks
Joel

 

[prcguy]

right now I am in receive only mode. ( a kenwood TS830s) I hung a home made dipole over the 2-nd story balcony just to have something to listen to.
each leg about 8.4 feet long. ( no TX till later) The balcony wasn't long enough for much more. Its boadside to east-west.
i have heard Sal in Tampa most nights really loud. Heard him talking to bob in Ontario. I think that was on 7 mhz. i don't know if that's an artifact of my antenna (I doubt it) or Sal's 1500 W.
in the early evening a few nights ago I heard england, germany, italy , Norway and Oregon and several in Canada and conneticut. Could hear about 5 different groups doing check-ins -- on in Delaware. Not really loud but very readable. The more I listen- the more I like listening.

The hill seems just too good to pass up.

Do yall know how to get ground rods in around the tower base if there is a lot of rock underneath the soil ?
( cordless hammer drill ????? )

Is your CB antenna one of those 8 foot stainless steel whips I used to see on everybody's pickups back in the 80's ? Have you tried tuning that for the longer wavelength bands to see if would match ?

Your 8.4ft long per side dipole should be fine for 10m but on 40m its at least 20dB down and probably more compared to an actual 7MHz dipole. 20dB is 3 1/3 S units. If you had an actual 7MHz antenna you might be surprised. For NVIS or regional comms on 80, 60 and 40m, maybe some 30m, going to the top of the hill will buy you nothing and may actually bring in more distant noise. For certain DX on some bands top of the hill will work better. I might suggest testing a SW receive antenna at the house using 40-60ft of wire and a cheap 9:1 balun to see what can be picked up on major HF bands like 80, 40, 20 and 17m. Or get a resonant 40-10m EFHW at 64ft long or an 80-10m version at 133ft long and see what the radio can really do.

For installing ground rods I use a hammer drill and a ground rod attachment. Just pull the trigger and put some weight on it. I sometimes hang extra weights on the hammer drill to speed things up and that can pound through some crumbly rock like sandstone, etc.

This particular CB antenna is an 18ft tall fiberglass end fed. A ground plane using 9ft steel whips will not tune to bands like 7MHz unless you insert a loading coil and lengthen the ground radials. Then you would have a lousy 7MHz antenna compared to a full size dipole of around 65ft.

BTW 4in spaced ladder line around 600 ohms is commercially available and usually has around 16ga wire. 400ft runs about $400. But the loss is very low if the radio and antenna interface is done right. I would consider a 133ft center fed dipole at the top of the hill fed direct with the ladder line then a good balanced output antenna tuner at the radio, one designed specifically for feeding balanced line.

 

[Catbrain]

i should have enough room horizontally for any of those longer lengths. may have to trim a tree or two.

I could also try hanging a dipole on the first , near part of the slope up the side of the hill.
Prob. couldn't get the center more than 15-18 feet off the ground though. That might be like 60 feet of ladder line......
Might try that when I am stringing the ladder line- cause thats where its route will be anyway. (to get up the hill)

Thanks I will read the grounding in shale doc. A golden nugget ! Thank you !

Tim