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Affordable antenna endpoint auto tuner for gutters

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Answers

  • Dave KD5FXDave KD5FX Member ✭✭
    edited March 2017
    When I lived in the land of HOAs which is otherwise known as Katy, TX I tried a gutter antenna using a close coupled antenna tuner, the MFJ 200 watt model. The tuner would tune the gutter just fine on 80 thru 10 meters. I could talk to anyone I could hear that was S9 or better. Problem is, I could hardly hear anything! It just didn't work well. 
    This was on a new house, the aluminum gutter was well installed and looked to be bonded at every corner and section. Total length was about 220 feet. The down spouts were isolated from the ground by a plastic section and the gutter itself was not grounded to the house. 
    I also had an 8 ft ground rod near the tuner and ran some 33 ft ground radials too. 
    Picture here:
    http://www.kd5fx.com/gutter.html

    I found that a stealth 104 ft (random length) black wire worked better. It was only 16 ga wire and I held it up over the roof a couple of feet with some pvc pipe (painted black) and it ran around on top of the gutter. Since the roof was also black it blended in very well. The XYL didn't see it for many months. The wire used the same ground and radials as the gutter, didn't even move the tuner, just ran the wire from where it was around the house using the pvc pipe standoffs. If you have a two story house this will get the wire up pretty high! Higher is better...

    FYI, I also once tried a full wave 80 meter loop that was stapled to the bottom of the eve all the way around another house. It didn't work either. 
    73, Dave
  • Mark_WS7MMark_WS7M Member ✭✭
    edited September 2016
    I too live in an HOA with many restrictions.  My first antenna I was able to shove up into a cottonwood tree.  I encased it in gray PVC so it looks like a big cottonwood branch.

    I was able to put up another antenna, an end-fed wire running between trees.  The wire is small enough that it is very hard to see unless you are looking for it.

    Without knowing your yard and situation my best first suggestion would be to build or buy a 43 foot vertical and mount it on a lean over system in your back yard.  You'd need to lay down some radials and put a tuner at the base but that SGC tuner mentioned above would be perfect.

    With this setup you wait until it is dark, lean the ant up, lock it in position.  Go have fun.  Just take it down when you are done.

    If you get creative you could do the tilt up/down via remote control using a small motor.  

    If you get really creative the 43 foot vertical is almost invisible if done right.  It can be ground mounted, as mentioned above you'll need radials but those don't need to be buried deep.  Just a 1/2 inch.

    One ham I knew had such an antenna mounted on his fence.  When laid down it was invisible since it laid behind the fence.  He built an automated riser that he could flip a switch and it would go vertical.  He operated for many years with no one knowing he had an antenna.
  • Dave KD5FXDave KD5FX Member ✭✭
    edited September 2016
    I also have a powerpoint file on Stealth Antennas on my website at:
    http://www.kd5fx.com/

    Look for 'HF Antennas for Stealth Operation'
  • Tim - W4TMETim - W4TME Administrator, FlexRadio Employee admin
    edited March 2017
    Antenna couplers like the SGC and CG Antenna can be used to make some very stealthy antennas that radiate very efficiently.  Get some insulated wire with a black or gray jacket and make a vertical with the coupler at  ground level.  If you can string up a flat top or doublet fed with ladder line connected to the coupler, that is even better because it is a balanced antenna design.  Or better yet, make a vertical loop.  I use the latter and have easily achieved DXCC and WAS on multiple bands.
  • Rick - W5FCXRick - W5FCX Member ✭✭
    edited February 2017
    Thank you all for the very helpful ideas.
  • HCampbell  WB4IVFHCampbell WB4IVF Member ✭✭
    edited June 2019

    You might not even have to compromise on performance with the “right” flagpole or stealth antenna:

    imageimage



  • W9OYW9OY Alpha Team Member ✭✭
    edited September 2016
    http://w9oy-sdr.blogspot.com/2009/09/43ft-vert.html

    Make sure to drill a hole in the ammo can facing the dirt to let out condensation.  You can virtually bury the ammo can if needed.  I fed it with RG8x   Make sure the piece of coax connected to the antenna is isolated from the feed-through connector and the ammo can.  I just drilled a hole in the can ran some coax through and taped over it with some aluminum tape to keep the bugs out.  The core is probably not necessary if you have more than 1 or 2 radials.  The tuner is held in place with a 2" SO239 bulkhead and a double male  The tuner is virtually an exact fit for the height dimension of the can so you have to accurately place the hole for this barrel connector to mate with the transmitter connector on the tuner.  To tune you leave the tuner power button on all the time and use the bias T to turn things off and on.  Send some power, like 10w down the line and you will see the tuner tuning on the SWR bridge.  Once the SWR is stable increase the power to 100w.  Occasionally you may have to cycle the power.

    45 ft radiator will get you 80-6m, 25ft will get you 40-6m.  Staple some radials to the yard using yard staples.  2 will work, more would be better.  For this antenna beyond 12 is diminishing returns.  12 will establish an excellent ground plane and there will be no common mode RF back in the shack on any band.  I have a full size 1/2 wave end fed 40M vert over 4K ft of wire and when measuring this 45ft antenna vs the high efficiency vert at the WebSDR RX at University Twente this antenna was barely 2-3 dB down compared to the better vertical.  I buried the RG8X which was some bury-able variant of this cable like Belden 7808WB.  MFJ makes a 926 outside version of this tuner but I bought my 929 off swap.qth.com for $100 and an ammo can for $10 at a surplus store.  I worked 100 countries in less than 6 months with this set-up using my Flex 5K.  If I needed to be super stealthy I wouldn't have a problem stapling the radiator (#14 solid black insulated wire) to the tree at the 100W power level or even wrap it around the trunk in a loose spiral.  You could use ideas from this for your particular application.

    73  W9OY
  • Rick - W5FCXRick - W5FCX Member ✭✭
    edited December 2016
    Lol. If I could get that cactus approved by the HOA it'd make it all worthwhile!
  • Rick - W5FCXRick - W5FCX Member ✭✭
    edited February 2017
    So the latest I'm seriously considering is to submit a request for a back yard landscaping project that includes some flowerbeds, a patio, hummingbird feeders and a bird bath, plus a 32' Martin house, which of course must be up high on a pole with guy wires in an inverted V configuration to stabilize the bird house pole. The bird bath is to sell the "bird lover" aspect so the Martin house (hopefully) doesn't get scrutinized as closely (probably won't install the bird bath). This would enable me to get an antenna up in the air, away from the house in the open, and have a purpose that's reasonable. I could go for the flagpole but there's a height limit of 20'. If the bird pole flies, a fiberglass hollow pole can house the vertical. This is in addition to some of the other stealthier ideas closer to the house that you all have provided. Many thanks! Rick
  • Norm - W7CKNorm - W7CK Member ✭✭
    edited February 2017
    Just a thought - If the bird pole flies, make sure you put in a bunch of radials.  You can also insulate the base of the pole and use an aluminum pole.  Put an auto-tuner at the base, connect a wire to the top of the pole and have it come down to a set of cleats a few feet apart where you can wind up the extra wire.   Make the total length of pole and wire around 90 feet.   During the day with the wire against the pole, it is a normal vertical for possibly 40m and up (32').  During the night, you can go outside, unwind the wire from the cleats and string it out to a fence, patio, tree, pole, etc.  It now becomes an Inverted L that will tune up nicely on 160m thru 20m.   Since 160 and 80 are usually best in the evenings, this may work out well for you.  When your done, wind the wire back up on the cleats and your as stealthy as can be.

    Norm W7CK

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