Technician aspiring to General needs HF antenna advice, pls!

[KB3SFU]

Hi all,

My name is Dave (kb3sfu) and I have been a Technician for a little more than a year now. I've been sitting on my General book not really doing much with it. I came into some extra mad money recently and I'd like to wrap up my HF station so I'll get motivated and finish studying for the General. I would sincerely appreciate the help of any ham who is knowledgeable about antennas to throw a few ideas at me. I believe there are better options out there, I just haven't found them myself yet... Read on:

Equipment I have collected so far:
ICOM 745
Heathkit 1kW amp

Equipment I still need:
Antenna Tuner
Antenna (!!!)

Budget:
$500-600

Limitations:
I live on the ground floor of what can best be described as "apartments-built-to-look-like-townhomes."  I don't have access to the roof, but I do have my own front yard (about a 10 foot square slab of grass).  I have my own private entrance, and my office window faces out towards the grass. I've bought books on "stealth antenna" setups and poured through the ARRL handbook on suggested setups for apartments, etc. but none really seem to work for my situation. The primary problem as far as I can see is that although the yard is "mine" it's not really mine to put things into or on.  So whatever I put outside has to come back inside when I'm done.  So I need something semi-portable. What does semi-portable mean? It means that while I'm not a lazy man I also know myself enough to know that I'm less likely to get on the air if I have to spend 30 minutes just to drag my antenna outside and set it up.

Best idea so far:
The best thing I've found so far seems to be the Outbacker Outreach 500 with it's optional base.  It seems easy enough to break down and drag into the house.  It can handle up to 600W PEP and it will do 75-10 meters which seems like almost everything I could ask for given my constraints. The downside to it is that I won't be able to use the full potential of my Heathkit amp, and there will be no money left over for a tuner... but honestly after looking at tuners that can handle 1kW I've pretty much resigned to just get one or the other this time around anyway.

Thanks in advance for any and all advice - 73's!

Dave
KB3SFU

[KG4RUL]

Given your situation, I would suggest that you forget about the amp as pumping a KW out at 5' from the house will not meet the FCC standards for RF exposure anyway.  Sell it and and use the funds to get the Outbacker Outreach antenna ($420) and the Outbacker Outpost mount ($280).  Using that antenna, you will not need a tuner and you will get contacts.

[KB3SFU]

KG4RUL - So you're in favor of the Outbacker too?  Is that antenna my only option?  It seems like the Outbacker is the only mobile HF antenna out there!  It has occurred to me to set the Heathkit aside for right now and just run Barefoot - but is the Outbacker my only hope?

[KG4RUL]

The other alternative would be to use the Outbacker Outpost mount with a screwdriver antenna.  I have done similar to this using the MFJ-1901  http://www.mfjenterprises.com/Product.php?productid=MFJ-1901 mount.  I attached a 5' section of RadioShack mast to the mount and used a 3/8"/24 mount (with a quick disconnect) at the top of the mast to mount a Lil Tarheel antenna.  I roll out 6-8 short radials and use some 4 conductor wire to extend the antenna controller cable.

[AA4PB]

I second the idea of NOT running high power in your situation. What if a kid touches your antenna while you are pumping high power into it? Your also likely to create a lot of RFI problems with neighbors if you run high power. I'd stick to the basic 100W transceiver and possibly even drop the output to 50W or even 25W if you have any issues.

Once you drop the high power requirement then you open up several more portable antenna possibilities. The Outbacker and screwdriver are possibilities. The BuddiPole is a short dipole option. There are a number of other portable low power antennas that could work.

Any unbalanced antenna like a vertical will probably require some kind of radials in order to avoid RFI issues. The Outbacker mount provides some capacity to ground but I seriously doubt whether it will be adaquate for the HF bands, especially 75M and 40M.

[WB0KSL]

Forget the RF emission standards, I think you are probably in more danger from the Frankenstein Mob Scene that your townhome neighbors will form outside your door if you run the amp.  And before someone chimes in saying that it's your neighbor's problem that the SuperAmp5000 Home Theater System he bought is poorly designed, etc. etc., I'm talking real world get-along-with-your-neighbors stuff here, not law school federal regulations final exam.

That said, If you anticipate modes of operation that don't involve changing your frequency often (PSK31 etc. for example) the small magnetic loops such as the MFJ 1788 seem to be well liked by those who have them.  I have similar constraints (not quite as severe as yours) here, so am on the cusp of ordering one myself.

73 - John WB0KSL  

[KB3SFU]

I'm not the kind of Ham that runs power just because... In fact, the only reason I bought the Heathkit was because a friend unloaded it on me for $300. I haven't been into the hobby very long but even I couldn't pass up a deal like that.

My main objective is to get something that makes the most of what I have while remaining portable.  If I can't run the Heathkit with a mobile HF setup, then the Heathkit will have to wait until I have a house.  I'm surprised that (most) portable antennas can't run power beyond a few hundred watts. I'm aware that "a few hundred" is more than I'll need when conditions are right, but I don't understand what is physically different about a mobile antenna vs. a stationary one that would make it unable to handle a bigger amp?

[AB2T]

Some hams run QRP SSB or low power SSB.  That might be an option to look into.  I don't operate that power and mode, but I'm sure that someone in Elmers can give you pointers on that. 

Antennas are always the most important part of the station.  This is crucially true in restricted housing or small property situations.  I encourage you to build a wire antenna first before buying a vertical or beam.  Get a copy of the ARRL Antenna Handbook.  There are scores of projects in there.  Be creative -- try different setups until you find an antenna that works for you.  You might also want to experiment with paints and different wire gauges to better conceal the antenna.  You might find that operating lower power SSB into wire arrays works well.  My philosophy: start with homebrew and inexpensive options first, and then advance to commercial products.
I've seen photos of wire arrays on restricted properties.  The antennas are so well camouflaged that it's almost impossible to see the wire and feed line from the street.

Courteous operation and careful listening often adds a few hundred watts to your signal.  Anyone can use an amp and push their way onto the bands with brute force.  But the skilled operator can often break pileups with patience and tact. 

 

[WD5GWY]

Some mobile antennas cannot handle the high power because of their construction. Others, can handle up to a KW with no problem.  High power out does not mean you will receive any better. If you can't hear 'em you can't work 'em!  That's why everyone is encouraging you to invest in a better antenna instead of using the amp. Save the amp for when you do get a house (hopefully in an area with no HOA restrictions......why I love rural living). Then you can run as much power up to the legal limit as you wish.
 Read the posts in this section and you will find some very creative antennas that work surprisingly well and are all but impossible for anyone to notice.  Of course they won't work as well as full sized antennas mounted high on a tower or towers, but, you will certainly make plenty of contacts, both stateside and DX.  I have even attached a 40' dipole inside my computer room/shack and tacked it to the top of the walls (9 ft. ceiling) and using an auto tuner, made contacts from 20 meters to 10 meters.  Didn't work as well as my dipole mounted 35' up in a tree outside, but it did work and better than I expected!
Amateur radio is about experimenting and learning and having fun at the same time. This is your chance to have some fun and learn about antennas too. As suggested, get the ARRL Antenna Handbook and try building some of the different antennas there. Or just copy what you can find on the net. No need to spend lots of money getting something up that may or may not work. Building your own antennas means if it doesn't work, you can take it down and re-do it and try something else, till you find what does work best for your situation.
Good luck and have FUN!!
james
WD5GWY
 

[WX7G]

A mobile antenna on a tripod is a good solution for you. For this type of setup I have installed the radials on the lawn and connected them to a brass screw pushed into the lawn. To go on the air the tripod is set over it and a ground wire from the antenna base to the screw/radials is attached using an aligator clip. The radials can be secured using biodegradable plastic lawn staples from DX Engineering. To carry the tripod outside, connect the ground clip, and place the mobile antenna on the tripod takes one minute.

For the ground I would install a dozen radials as on your 10' x 10' lawn.

The Outbacker is rather expensive for what it is and band changes are not quick and easy. Comparable performance can be had using Hamsticks at $30 each. Once a Hamstick is tuned it does not need to be retuned. To change bands walk outside and exchange one Hamstick for another. DX Engineering stocks the Hustler quick disconnects that make changing an antenna a 3 second operation.

MFJ has some reasonably priced antenna tripods as well as their version of the Hamstick. I run a 40 meter Hamstick at 400 watts with no issues. Another choice, and one that is as efficient as a Hamstick, is a Hustler mobile antenna. With these you have the choice of whatever mast length you desire. 3', 6, or gang then together for a taller mast. DX Engineering sells these. I recently tested a Hustler RM40 resonator on a 6' mast against several other mobile antennas. The Hustler and the Hamstick exhibited the same radiation efficiency. The Tarheel screwdriver has twice the efficiency but this is with a very good ground (7 ohms). As your ground resistance will be higher the difference between a 40 meter Hamstick or Hustler and a good screwdriver will be only 1-2 dB. On 20-10 meters the difference will be even less.

For you I recommend the Hamsticks so you can get into this at a low cost and have some money left if you want to try a different antenna. The Hamsticks have low wind loading and the tripod will be less prone to tip over in the wind. You might start with a 40 meter and a 20 meter Hamstick and go from there.

If you want an antenna you can tune from the shack one of the screwdriver antennas will fit the bill. I use a Tarheel 200A HP that is rated for 1500 watts. These run $389. This is what I use for my main stealth antenna. I have different whips and such to enable operation from 160-10 meters. I use this for low band CW DXing.

 

[K5LXP]

Looks like pretty much all the bases have been covered as to what would fit in a 10x10 spot.  All of them will "work" so some degree or another and may be adequate depending on your expectation.

By any definition, a 10x10 spot isn't much to work with for any type of HF antenna so you'd have your work cut out for you.

So, what are the chances of moving the antenna somewhere else?  You mentioned you didn't have roof access but is there a park, vacant lot, common area or other open spece within a few hundred feet?

That's how I solved my antenna situation at a couple of apartments I've lived.  I just ran coax to a nearby area with trees and set up either wire antennas or verticals.  Even a few dB of loss through a long run of coax to a decent antenna is much better than a short run to a compromise antenna.

Mark K5LXP
Albuquerque, NM

[KB3SFU]

Thanks to everyone for their suggestions - I have a lot of bookmarked websites to read now and I appreciate being shown that I at least have more options than I was able to find. Unfortunately K5LXP, I'm on the corner lot and I look out over a vast parking lot - nowhere for co-ax to go! 

A question about radials: I have already purchased a ground rod, can I substitute it in place of radials? Can I hammer it into the lawn close to the house? That would be ideal for my situation, but it seems like it might not be good to ground so close to the building.

WX7G - I really appreciated your detailed response, thanks! Lots to read!

-Dave KB3SFU

[K5LXP]

A ground rod cannot in any way, serve as any form of RF ground or counterpoise at all, for any type of antenna, ever.  You need metal, not dirt to provide return currents.


Mark K5LXP
Albuquerque, NM

[WX7G]

A ground rod will work but the ground loss resistance might be 50-100 ohms, rendering the antenna very inefficient.

You can start with a ground rod. Then tune up the Hamstick or Screwdriver antenna on 28 MHz. With the small counterpoise area you have you can assume that the ground loss resistance will be high enough that the 28 MHz antenna base resistance will always exceed 50 ohms. If you measure a minimum VSWR of 1.5:1 you know that the base resistance is 75 ohms (75/50 = 1/5). If 2.0:1 the base resistance is 100 ohms. 

Doing this you can record the decrease in 28 MHz ground loss resistance as you go from a ground rod only to two radials to four radials, and so on. You then have some data to decide how many, if any radials, you want to use.

One small yet effective antenna that hasn't been mentioned is a small (but not too small) that requires no radials can be made using the MFJ MFJ-936B loop tuner. A loop for 40 meters can have a perimeter of 20 to 33 feet. This should work as well as a mobile antenna. The limitations are: only two band coverage for a single loop length and 150 watts.

[KH6DC]

I agree with the others, keep the amp for later but not right now, you might cause RFI and everyone will find out it's you jamming their TV, telephone, etc.  I say keep the linear but don't use it now just to hone your skills busting pileups during a contest like Field Day just barefoot at 100 watts or less.  For the antenna tuner, a correctly tuned antenna will not require and I learned from other hams to tune the antenna first before trying a tuner.  I believe the 746 has an internal tuner but it's been many years since I sold mine.  Now for the an outbacker outpost with the outreach is fine, a tripod with a screwdriver antenna you can manually tune is great and would be better than the outbacker antenna because you can manually tune it.  When SWR is low, the signal or the noise is the loudest or you can use a semi-auto tuner like the Tubo Tuner  http://www.n2vz.com/ that connects to your radio.  Screwdriver antennas like High Sierra, Hi-Q, Tarheel are good choices, I have Hi-Q 2/80 which have a slim profile. Good luck