The AM Forum

So,

The possibility exists that I might be moving to a new QTH in about a month or so. Prime antenna weather. :-)

Come summer, we'll be looking at replicating some of the antennas that already exist at the current QTH, but in the meantime, what's a fella to do for some fun on the low bands all winter radio season?

New place has some decent trees behind the house that extend quite a ways. Some sort of dipole could be put up in a N-S direction at maybe 50 feet or so. We have bows, slingshots and a half built spud gun thingie to launch wires with.

Tuners consist of an MFJ-998, rated at 1500 watts autotuner, and a TenTec Manual L tuner rated at a KW. I'd like to be able to run QRO with the Ameritron 1306 as I do now.

Current antennas consist of a 160 horizontal loop, 80 horizontal loop, and 40/60 m fan dipole and a C3 for the higher bands. And  butternut vertical HF-6.

Bands of interest in the winter are primarily 160,75,40.

Migrating the HF6 is likely doable, though getting ground radials might be hard in snow covered ground. But I don't see that as a primary antenna, especially QRO.

Thinking some sort of dipole that would lend itself well to multiband and be decent down on 160. I know 50' isn't high enough, but my 160 cloudburner loop at 20' has been fun enough that if we can equal or beat that I'd be happy.

Looking for suggestions. I've got a zs6kbw variant on a G5RV out at a remote site, and that works pretty well on all the even bands from 75 up, but has a fair bit of SWR on 75 and don't think it plays on 160, never tried it.

Thanks!  :)

I'd just go with the biggest loop, fed with open wire - it should get you on all 3 bands.

With any luck I won't be putting up the one antenna I already have up, this Winter. ;D

K,

Just roll the radials out and cover them with snowballs. That's how I run my eL. Tomorrow the ground will have a nice covering, and I'll place 'em over the lawn. Worry about them in the spring.

klc

L going up for 160M. Heck, with all the water in the ground radials MIGHT be optional! :)

Open wire line fed antenna is the way to go for a multiband antenna.  I have 240' of wire up fed in the middle with HB OWL.  Works fantastic on 160, 80 and 40M.  Been up at this QTH for almost 40 years now.  Get yourself some ladder snaps and build the OWL.  DX Engineering has some 14 gauge wire that is insulated with a material that is not bothered by UV. 

You will need a balanced tuner.  Either build one or modify the one you have.

Joe-W3GMS   

Joe, I was thinking along those lines. What about using a single ended tuner, coax through the wall,  followed by a balun to OWL?

What are ladder snaps and where does one source them?

I have a stuff roll of old copperweld wire, perhaps this would be a good mission for it.

You can do that if you keep the length of coax real short and very low loss.  The problem is, the reflected impedance of the multi-band antenna is all over the place.  One band its current fed and then on the next band its voltage fed.  The coax will be severely mismatched where its connected to the balun, hence very high losses.  Again, if the coax is short, you can get away with it. 

I have seen folks run two pieces of coax through the wall.  The grounds of each coax are connected together and only each center conductor connects to the open wire line.  In that case, you can then move the balun inside near the tuner where it really wants to be.  My preference is to use a current balun on the input side of the tuner, but that is an entirely different subject!   

I was trying to find the snap spreaders online, and I was not able to find them.  I hope they have not gone out of business since I want to buy some more! 

Joe-GMS       

K,

I've an axe you can borrow if you are going to do some winter work.



Look at this...


http://amfone.net/Amforum/index.php?topic=27148.0


klc

Don't need no stinkin coax ! !  Run da ladder line through the wall.

Here is the link to the spreaders.  They work excellent.

http://www.dtsohio.com/73cnc/laddersnap.html

73,
Joe-W3GMS

http://trueladderline.com/w7fg-design-dipoles/160-10m-x-150-feedline/

Very pleased with mine, well constructed and saved a lot of time not having to make the feedline. Still trying to find the sweet spot for 160, but on other bands it tunes right down to 1.0:1
The thing that most intrigued me was the amazing drop in background noise and RFI that other antennas pick up here.
Bruce has been great to work with.
Carl

There's something wrong with that web site. The PayPal link goes to a non-existing web page www.73cnc.com. That's where the "Contact" page links to also.  I'm leery when things like that happen, seems like a hijacked domain name.

August KG7BZ

I have been ordering them for years and never had an issue.  They do give the option of ordering over the phone in addition to an email link for questions. 

I am about ready to order another 100' worth of spreaders and if I have a bad experience, which I don't think I will, I will let everyone know. 

Any reluctance, give them a call.

Joe-W3GMS   

Hi Kevin,

My advice would be to put up an open wire fed,  straight, center-fed dipole as flat and high as possible. Make the dipole length for the lowest band (160M) at least 3/8 wavelength = at least 180' long.  If it will not fit in your lot, then dropping the ends straight down on each side is OK.  Put the dipole in the clear away from the house noise and power lines - as far as possible. The tiny extra open wire feedline loss will be negligible compared to the reduction in overall noise.

Feed with good quality open wire line, low loss thin spacers, at least #12 wire or larger. There will be hot spots (high current points) along the line on many frequencies, so you need heavy wire, including the flat top. The less contact of the spacer to the wire, the more environmentally stable the feeders will be in bad weather.  No spacers at all, (taunt wire to the tower) is all air and the best OWL you can get.

Orient it broadside in your favorite directions (broadside SW / NE  here in CT)   because it will be very directional on 75M/40M and higher.  Cloverleaf or octopus pattern on 40M and higher.     (A separate 33' dipole fed with openwire for 10-20m is a great idea to preserve a clean figure 8 pattern using the same tuner)


And to cover ALL bands from 160-10M with ONE antenna, you must make the tuner configurable for both parallel and series tuning.  Most commercial tuners do not offer this feature, thus have some problems getting a good match on certain freqs. This makes us have to lengthen, shorten or whatever the feedline length. Having a simple way (jumpers or a switch) to change the feed config solves this problem and gives a 1:1 swr on ANY freq from 160 - 10M using the simple link-coupled homebrew tuner below.


Simple Homebrew Tuner -  thread:
http://amfone.net/Amforum/index.php?topic=41369.0

How to configure it for parallel OR Series feed:
http://www.amwindow.org/tech/htm/160smallants.htm


Good luck!

Tom, K1JJ

....I wouldn’t put it up today!  Yikes!  17 degrees down here on CT shoreline in Stonington.  Happy Frozen Turkey Day to all.

Antennas always work better when you put them up in adverse conditions!  It adds another 10db to the signal  :).

Happy Thanksgiving to all of you and your families.

73,
Joe-W3GMS

Thanks for all of the good info. Carl that w7fg setup looks like a good potential and also thanks for the links to the snap on ladder line, 'GMS. Going to lay in some of those against future use.

'JJ - there's a line of woods behind the house, far away from most sources of noise - nearest neighbor is about 850', with a set of solar panels. They are fairly mature trees, maybe 50 years or so, so I think I can get about 50' feet out of them. Possibly more. 240' of line plus feeder is a lot of stress- I'm wondering about running the dipole over multiple branches for some support. Might let it be a bit less straight. Or I can go for a clear shot and pull tight.

With a full 240', plus feeder, will I need to go series and parallel? Should I have my eyes out for a KW matchbox, or some other tuner? I can build one eventually, but have gotten used to the convenience of autotuning too.

We'll see if this works out. Then we can look for a place to put up the 630 meter dipole...  ;D (actually, saw an interesting antenna used by a VK station, wire to the top of a tree, vertical section  down for the high current section, and then loading wire at about 10' for an end fed halfwave overall.

That was drilled into me as well!

I remember a January VHF contest when I was with Harris RF where we secured space in a home on a hilltop south of Rochester. It being constructed but was quite high and he let us into the space because the owner was a ham building his dream house. It was framed with a roof and western wall. We were camping in what would become the downstairs bathroom. I was up on the roof lashing up our two meter beam and rotor while the wailing wind was stripping shingles off the roof next to me. Worked great. Talked to Texas on 2 meter SSB with 10 watts that year.  ;D

Yep, antenna projects like that are good for the soul and "S Meter"!   We were helping a local Ham put up a 40' mast today and it was in the 30's with some wind.  Since it was not that cold, I told him he only would get about a 5db advantage out of it  ;). 

I use a Palstar balance tuner that I like a lot.  It not inexpensive, but is build well.  Keep an eye out for one and pick up one used.  Its one of the few tuners that I have not caught on fire!  Mine is the AT-1500 BAL.  Its not made anymore, but they sell another model that is similar.  My 240' Center Fed antenna is fed with #14 gauge open wire line.  That antenna tunes nicely from 160 to 10M.  I only use it on 160, 80 and 40.  Above that, its just too long to be a stellar antenna, but does work.   The topology of that tuner is based on the Rick Measures balanced tuner write up in an early 90's QST.  For your line length, I would use a minimum of 14 gauge wire for your feeders. 

Joe-W3GMS       

Joe,

You always have a stomping signal  up here in central NY, so that arrangement is obviously working well.

I think my first pass will be a 240 foot with open wire, a good balun, and my existing tuners. Then I can cast about for a balanced tuner or maybe look into building one. Looking at some of the baluns from DX engineering with a couple of feet of coax to the tuner. I've seen discussions that suggest that lower impedance open wire line is easier to match, that the line should be certain lengths (odd multiples of 60') and that the flat top should be shortened some from 240'. Any comments on those?

Still not sure this is happening, but it's fun to plan.

Thanks for the signal report!  Yes, the antenna has been up 40 years without a failure and typically I get great reports. 

I would avoid odd number of quarter waves for the OWL.  I have always used 600 ohm stuff I made many years ago and its works well.

Here is a good site talking about all this stuff: 

http://www.hamuniverse.com/feedlinelengths.html 

Yes, go with what you have as far as the tuner situation.  Not sure of how much power your running, but plenty of folks run a tuner into a balun to get a balanced output.  Running QRO, you can get into some real trouble with that topology since the reflected impedance is all over the place with a multi band dipole and the effects are vividly demonstrated.  My two favorite tuners are either the Rick Measure design with a current balun, made of coax  on the input or the old style link coupled tuner that does not use any balun.  For a 100W class station, I think you can make your initial scheme work fine until you homebrew something up.   

73,
Joe-W3GMS
   

Joe,

I've listened to you on the AM PM net for years while mobile all over the state up here in CNY, up to the Adirondacks and down into CT and you always are head and shoulders above most of the other stations.

I've got a small amp, an Ameritron 1306 which I've been running 150-200 watts carrier with. The DX engineering baluns are rated 5 KW CW or 10KW ssb, with teflon wire for high voltage. I'm hoping that might be enough to work well on most bands with those power levels. The extra 6 db over barefoot seems to help a lot. If things get unhappy, we can always dial the drive down on the Anan.

I see in another thread that Carl has shortened his dipole and trimmed the feedline some. I'm wondering if I should start with the stock lengths, or plan on doing that right off to help. I know from running marine stuff with a backstay or wire up the mast that a non resonant length helps keep impedance excursions down over using things that are half waves on certain frequencies and I suppose that probably applies here as well.

Just looked at that website and that seems to agree. Handy site.

Did house inspection today, so maybe this is going to happen, pending a few more steps.

It is particular, that's for sure. Added about 10 ft of feedline to see if I could drop the low end of 160 some more. Net result is all the 1.0:1 (except 3.8:1 on 1801) matches on 160 went up to 5-8 :1 and I lost 60 meters. Back to prior length.

What boat were you feeding the backstay with? I had Cape Dorys for many years and used a Hustler mobile on the back porch fence with good luck.

Carl,

For a sailboat we had a Bayfield 24. I fed the backstay for a while, then went to a 29' wire from the corner of the cockpit up to the flag halyard fed by an AH4 tuner. Worked good on 80 and 40. On the old Tugboat we used the same AH4/706 combo with a wire up a fiberglass whip over the pilothouse, back to another pole at the stern end. We used that one less because of the gas engine and ignition noise, but was fun to listen to and work at various times.

On a trip up from Oriental NC to Kingston NY I used an ICOM 703 with a buddistick arrangement clamped to the cockpit rail. That worked well too, although the coil got tarnished from the salt air quickly. Next boat I hope to have some sort of long term HF arrangements on it.

Anything that won't ice up !


Lou

Someplace, lost to the mists of time, I remember reading about a station that had an antenna that was a continuous circuit, like a folded dipole or T2FD. They kept it ice free by running power through it when it wasn't in use to keep it warm.  ;D

A deckhand with a broom to knock the ice off........

KLC

  In the Collins Collectors magazine "Signal" there was a story a few years ago about a system they built for the Navy that was used airborne and was very low frequency. In that article they mentioned that there was a ground station in Maine. The Maine station had two antennas and its own generation, 5 MW if I remember correctly. The antennas were huge wire arrays and in the Winter when icing would be an issue one antenna was on line. The transmitter used 2 MW and the other antenna was reconfigured as a load for the generation system's other 3 MW of capacity. They would switch between antennas as the one being used for transmitting began to ice up.

That may have been what I read about, although I don't recall it being such a low frequency system. Those low frequency systems for talking to subs are interesting. Very narrow antenna bandwidth so the CW has to be slow and shaped to control the bandwidth. In the air they fly circles with thousands of feet of wire trailing behind down into a cone shape oriented vertically. I would have loved to have sat in the design sessions for those systems.  ;D

Agree! the high big flat top with open wire feed is what serious folks run when they run out of patience. Very good performance - problems are few. And yes that essentially takes all the fun out of it.

So I just put up my first 80/40 Trap Dipole with old school home made traps and coax. Lots of fun understanding what was going on. Tuned em for 6.7 MHz.

I also like big vertically oriented  loops like a full wave on 80M. I have run them terminated with a balun for multiple even bands, and not for single band or open wire feed.

And I have always liked the elevated radial Groundplane idea for wire verticals for DX on 75M.

Update,

Closed on the new QTH. W7FG 240' with 100 feedline on order. In the meantime I've hung my ZS6KBW doublet up as a temporary measure. Feeding through a DX engineering 1:1 5KW balun. The KX3 was happy with it from 40 meters up through 6 with it's autotuner. Not so happy on 3885 though. When I get a power supply and a Kenwood TS480HX setup with an AT200 tuner we'll see if it likes the other tuner better. Need to scope a better path for the big antenna when it arrives around the end of the month. I didn't realize they didn't ship from stock but built them for each order with a couple of week lead time. Should have ordered sooner.

Moving in the mud and cold is not so much fun. And it looks like I'll have to track down at least one 60 hz buzzy of some sort on the site.

anyone have any experience with pneumatic launchers?   Need advice on launching a line into or over trees such as launch angle.  my homebrewed launcher has not been put to the test yet.  It has a fishing reel with mono filament. My fear is wind knots from any cross wind and a quick unwind from the reel.  Basically want to put a #14 THHN long wire into the woods behind the QTH.

Take a look at Jeff K6JCA's blog. He has done a couple of rounds of launchers and has some practical advice:

http://k6jca.blogspot.com/search/label/Antenna%20Launcher

  Borrowed this from the Whitman Radio Club while visiting my sister in Wareham in October, uses a sprinkler valve and two 9 volt batteries. The barrel screws onto the valve and is 1 1/4 inch schedule 40 PVC, the projectile is 3/4 inch schedule 40 PVC with end caps and has something in it for weight, sand maybe. The holding tank is 3 inch schedule 40 PVC. I pressured it to 100 PSI.

  It works very well, I have used the sling shot and lead weight launchers which don't work as well. The lead weight doses not have the weight to pull the line over and down from a branch nor does it shoot as high.

  This launcher will shoot quite high and one needs to be careful as the projectile has speed and weight, it would hurt some one. I hit the tree on my first shot and shattered the projectile, second shot not that I had an idea of where it would shoot went right over the tree limb at was at 45 feet. I had trouble pulling the transition from mono filament to nylon cord over the limb, I probably should have use some plastic tape to tapper the transition so it would pull easier.

I've used bows and weighted arrows, slingshot with lead sinkers, and I'm about to use a pneumatic launcher. Whatever you use I strongly advise making sure the line is free and won't snag. If it does, the monofilament line you use will absorb the energy by stretching and then return it by zinging the payload right back at the launch point, which with a bow or slingshot is right in front of your face. Ask me how I know this... :o

Maybe a bit weird but I'd put a 140-500MHz discone on top of the tower this winter, if it were possible.
As usual, LMR-400, ugh -100 FT of it. Yuck 2.7dB loss.  why even do it.

I recall reading about a fisherman getting killed by a lead sinker.

https://www.fieldandstream.com/death-by-sinker

Everyone has their own antenna erection schtick - mine is the bow and arrow.  I have used a bow and arrow since Boy Scouts merit badge.  


Some pointers:

If new at archery, then buy a cheap used recurve bow  ($20) and practice on a cardboard box target every day for a week to get good.

Stick a spinning rod handle into the ground with 6 pound test nylon monofilament line. (no more than 8 pound test to maintain accuracy and min drag)  Make sure there is plenty of line on the reel, spooled up near the lip for easy out-flow. If you lose too much line due to breakage, add a full dose because  a knot will cause flow problems.  Tie the monofilament to the arrow's end at the slot. I never had to weight the arrows - if your aim is good. They go right thru effortlessly.  Always launch the arrow from the woods >  into the clearing or back yard. Pick a tree crotch and aim carefully. There will be really bad windy days when it takes 10 tries - but most other days the first try is golden.  I can accurately thread thru 100' high crotches if needed. A minimum 25 pound recurve bow is good.

Feed a heavy string, then light rope thru the crotch and end up with 3/16" stainless aircraft cable. (Guy cable works even better because it's smooth.)  Tape up the rope feeder knots so they are smooth and will pass thru the crotch easily.  Try to support the center of the dipole and there will be little load on the end tree crotches -  and the cable will be less apt to work its way into the tree limb over time.

T

So I finally got the spare cycles and weather to put up the W7FG antenna. It's a 240 foot long (160 meter) antenna and I had it come with 100 feet of feedline. Picked the best trees I could around the hacienda and got it running more or less NS (20/200 degrees). The trees were not as tall as I hoped, based on the feedline coming down to the ground it's about 45' up. To get the feedline to the port in the window (MFJ pass through panel with parallel feed standoffs) I ended up cutting it to 50' which was listed in the green on the hamuniverse site mentioned above.

Last night I was able to load it up with the TS480 and the AT200 pro through the 5 kw 1:1 balun and test it on the various bands. It loads up fine on all bands except 30, and 160!  :o

Previously I was running a ZS6KBW doublet, 102' fed by 40' of 450 brown stuff, and it loaded fine on 80-10, too short on 160. So I expected this one, twice as long, would run well on 160 and hopefully on most of the upper bands. But it's not happy anywhere on 160. The tuner can grudgingly get it down to about 2.5 to 1. It doesn't seem to matter which end of the band I'm on, I tried every 50 khz up and down.

This weekend I'll put an AIM4170 analyzer on it and see what it looks like, have to get the software on a new laptop first.

Wonder which way to go in trying to get it to work on 160 and still work ok on the other bands. I can probably shorten up the feedline 5-8 feet, I've got it pulled to the side a bit to add some length and get around a corner of the house. It did do a nice job on 60 meters this morning.

Thoughts?

So I ran the AIM4170 on the antenna and got the following results. Looks like it's resonant quite a bit below the band around 1.575. OTOH 75 meters looks like it's high in the band, and 40 meters very low again. I'm thinking I need to shorten the antenna some.

Talked with Brian the fellow who runs the antenna business now and he said shorten it by 10 feet by folding back the wire. Did that. It moved it about 150 khz. Did it again, now it's about 1775 khz. Arrrgh. Now I'm reading that folding back the wire (zip tied and taped at the ends) may not 'shorten' it as much as just cutting it off. I think this thing is going to be up and down 10 times before I get it to tune. I'll be on 160 just in time for thunderstorm season. :-)

Any thoughts on the fold vs cut tuning?

Thanks