Antennas for postage-stamp sized lots

[ka3jjz]

If you live in an urban environment then trying to put up a good full sized antenna - even a PAR- could present some challenges. Adding to the issue are HOAs, which makes things even more difficult. If you can't use a vertical (stands out like a sore thumb) and don't want an active loop, what can you do? My brother lives on such a lot. It's so small my 2 year old nephew can easily throw a ball across it.

Here are just a few ideas I've come across....

Active whips (E Field antennas) - I'm no fan of these kinds of antennas, of which the PA0RDT is probably one of the best known. I have also read that a good deal of work is needed to tame them - it's not a simply slap it up there and it works. Here is an interesting article from SWLing.com on the subject...

How to properly install a Mini Whip antenna in an noisy urban environment

Many thanks to SWLing Post contributor, Grayhat, who shares the following guest post: Setting up a Mini Whip antenna by Grayhat I’ve been fiddling with my “balcony antenna” experiment for quite a w…

swling.com

Hidden Wire Loops - These are invisible (or nearly so) to a HOA or even a neighbor...some of these come from the SWLing.com blog...

The Loop on Ground Antenna - the "LoG"

A prototype receiving antenna for HF

kk5jy.net

160-20m LOG loop-on-ground

Like jjz, this I love my loops but this time decided to try on that is totally on the ground. RX ONLY. I don't have room for beverages, and have been down the so-called "snake" on ground antenna before, with unpredictable results. This loop is predictable. Basically it is a 15-foot square...

forums.radioreference.com

Guest Post: KK5JY’s Porch Loop Receiving Antenna

Many thanks to Matt Roberts (KK5JY) who has kindly given me permission to re-post the following article he recently published on his website KK5JY.net. Many thanks to SWLing Post contributor, Grayh…

swling.com

Video: Paul’s large aperture “Volleyball Net” loop antenna

Many thanks to SWLing Post contributor, Paul Walker, who shares the following video and notes: Here is a 10 minute narrated, detailed video on my 25 foot long by 10 foot tall “Volleyball Net&…

swling.com

If you sit somewhat away from the street - and have understanding neighbors - these wire antennas just might fill the bill

EWE Antenna review :: DXing.info

Review of EWE Antenna

www.dxing.info

How to Build a Simple Linear-Loaded Dipole for Low-Noise Shortwave Radio Listening

Many thanks to SWLing Post contributor and RX antenna guru, Grayhat, for another excellent guest post focusing on compact, low-profile urban antennas: A linear loaded dipole for the SWL by Grayhat …

swling.com

You will likely have some bands that will work better than others, but these might be a better bet than just 'throwing a wire out there' as I have seen a few folks here say.. Sometimes a little science is helpful, too....Mike

 

[vagrant]

This is a great thread. By pulling from the RR Wiki links to address the small lot, HOA concerns, or at times the ultimate keep the spouse happy by not having "those ugly antennas" everywhere, you will help many who may never look at the Wiki. I have made and further tested several of these antenna types. It was indeed educational. My favorite of the above is the End Fed Half Wave, as long as you can get it up into the air. The wire can be quite thin and difficult to see which is a good thing in this context. Even if one had to run it on top of the fence line, it would help. Additionally, two of these running perpendicular to each other and a switch inside the shack can improve things for directivity.

Taking it further...

For those that try one of these antennas yet still have, or already have too much noise/RFI, you may want to look at the RR Wiki for loop antennas. The small versions of these antennas allow one to turn it and typically reduce/null the noise/RFI to some degree or entirely. These can be made or purchased such as the RTL-SDR.com version of the Youloop portable antenna.

Additionally, an AM broadcast filter may be very helpful. These may be a notch filter for the entire AM broadcast band, or in the form of a High Pass Filter that allows signals above the AM Band to pass. I have an AM filter made by Dale Par and it works great. I also have an RTL-SDR AM High Pass Filter (HPF) which costs five times less and also performs very well. There are of course differences between the two, but for less than $20 to test and see if it helps, it is worth it.

Oh, I almost forgot. I am a fan of passive antennas and I should note that a preselector can be a very helpful addition to one's setup.

Update: I did forget about possibly adding an RF choke as well to the feedpoint. I added a commercial version and it dropped my noise floor by two S units which is significant. Still, that was on one particular antenna and should not be assumed that it will do the same on other antenna setups.

( I added the RTL-SDR brand items to the appropriate areas of the Wiki )

 

[ka3jjz]

Yes, all that might be helpful in an urban setting, but I will add one caveat - I would recommend a passive preselector, not an active one in such environments. The difference is that a passive preselector doesn't have any stages to add gain - something we definitely don't want to do in an area where there might already be too much RF floating around. These are quite useful for SDRs with little or no front end filtering such as the RTL-SDR v3 or the Funcube, just to name two. We have a few examples here...

Improving HF Reception - The RadioReference Wiki

wiki.radioreference.com

No one solution would fit all. This is an area where experimentation in your local RF environs is going to be key. Just be aware that such solutions exist- be ready to do some homework if you wish to tweak your installation further

Mike

 

[ka3jjz]

Here's some ideas from Palomar Engineers - go about 3/4 of the way down the page to where it says 'Bullet 55 typical configuration'. This setup only needs about 37 foot of space...

End Fed Antennas - Palomar Engineers®

Stealthy end fed antenna for portable, emergency, permanent locations - 1.8-61 MHz, 500-5000 Watts PEP. Quick setup, no radials, low SWR, neighbor friendly.

tinyurl.com

Mike

 

[prcguy]

Palomar and other companies offer these 9:1 types for transmitting but they don't work very well for that, especially a 37ft long wire on 80m. They do work ok on receive and you don't need a 500 watt or 5kW rated transformer for that. There are lots of articles on making your own 9:1 transformer for just a few $$ they work great for SWL using various lengths of wire.

Here's some ideas from Palomar Engineers - go about 3/4 of the way down the page to where it says 'Bullet 55 typical configuration'. This setup only needs about 37 foot of space...

End Fed Antennas - Palomar Engineers®

Stealthy end fed antenna for portable, emergency, permanent locations - 1.8-61 MHz, 500-5000 Watts PEP. Quick setup, no radials, low SWR, neighbor friendly.

tinyurl.com

Mike

 

[ka3jjz]

Yeah you can only bend the rules of physics so far. Still it would be better than a wire thrown on a floor...Mike

 

[ka3jjz]

I'm no fan of E field active verticals, but these 2 deserve at least a mention. Both pump out a pretty substantial amount of gain, and I would hesitate to use them on anything less than a good desktop (JRC, Drake) or ham transceiver. Anything less and there's a good chance that overloading is going to cause you grief

MFJ-1024, ANTENNA, SWL OUTDOOR ACTIVE ANTENNA, 50 kHz-30 MHz

MFJ Outdoor SWL Active Antenna "World Radio TV Handbook" says MFJ-1024 is a "first rate, easy-to-operate active antenna ... quiet.... excellent dynamic range... good gain... very low noise factor.... broad frequency coverage.... excellent choice..." Mount it outdoors away from electrical noise...

mfjenterprises.com

https://www.eham.net/reviews/view-product?id=12619

And how about a name from the distant past? Does the name Dressler ring any bells? Once upon a time, this company (which I think was in the UK) and Datong were neck in neck in the topic of active antennas.

Broadband Power Technology - Antennas

Yeah it shocked me to see these antennas again

Both could likely benefit from the grounding ideas from the SWLing.com blog mentioned above

Mike

 

[mass-man]

Hustler 4BTV...4 band and you can adorn the thing with an array of non metallic camo thingys! Think plastic wreath material...my former QTH had such a yard and the antenna was decent!

 

[ka3jjz]

I would imagine the performance fell off outside the ham bands...and this is a receive only forum (cough cough)....Mike

 

[highwayman1224]

I lived in an apartment and put my Wellbrook on a tripod in my little back patio and it was awesome.

 

[ka3jjz]

Unfortunately this is out of stock, but for a receive only application, might work OK.

My Go2 Antenna — TN07

My Go2 Antenna is specifically designed for HOA owners and portable / Emergency communications operations. HF antenna - operates on 80-6 meters 3.5 - 55 MHz; SWR ≤2:1 no antenna tuner required. Supports ALE & frequency hopping - no re-tuning!

tn07.com

Mike

 

[KB4MSZ]

If you can't use a vertical (stands out like a sore thumb) and don't want an active loop, what can you do?

Maybe you should just sleep on it for now.

 

[ka3jjz]

Actually some folks have loaded metal bedsprings.;..Mike

 

[KB2GOM]

You might want to check this out: Stealth Amateur Radio

Kirk is a pal of mine, and I wrote the foreword to his book, but I have no financial interest in promoting it.

Kirk was an editor at QST and regular columnist for Spectrum Monitor, and he knows his stuff.