Portable Operations Ideas Part 1 of 4

Like most hams, I envision using my radio in the field as much as possible.  I don't claim to be an expert, but I do read a lot and network...something all hams should do.  While I don't backpack with it, I'll mention factors associated with carrying your radio in a pack.  But, for a lot of hams, just having their radio in the outdoors is a lot of fun.  Doing some DX from a national park, or from atop a mountain, etc. can be quite satisfying.  Drive to a location, set up the gear and enjoy the day.  Bring some food and sodas, and it's a fun day, regardless of DX conditions.  So, here is an article which addresses some considerations.  It doesn't include everything there is, and it is my own personal opinion.  But, I hope you'll gain some additional insight into making your own portable station.  Questions to consider are what to use, weight considerations, effectiveness and of course, cost factors.

For simplicity, I won't go into detail about the differences of QRP radios.  They range from single channel kits that fit into Altoids containers, Elecraft models, up to radios such as the Yaesu FT-817ND and FT-857D.  As I don't do CW, obviously a phone radio is my choice, and Yaesu is my brand of choice.  I also won't discuss CW paddles.

You need a good quality antenna.  That doesn't mean expensive.  Lots of QRP'ers make their own dipoles out of small gauge wire.  The end result is usually a dipole, which can be mono band, or multi-band with alligator clips for band jumpers.  Both are reasonably easy to make.  Plans are available for the jumper version, and I can either tell you how to do it, or point you to an article.  Throw support lines over trees and you're ready for some DX.

Another fantastic antenna is the EndFedz antenna, now made by LnR Precision.  Dale Parfitt, of PAR Electronics designed and made them for years, but Dale has so much government work that he sold the business to Larry Draughon.  Both companies are great to deal with, and eager to talk about the products.  With LnR, you'll probably get Randy Drake, who usually goes into great detail when answering emails.  I prefer the EndFedz antennas because they are super easy to use, either as a horizontal, vertical, sloper or inverted L configuration, and have a built-in balun.  Most of the models are 100 watt mono band, although there is a 10/20 meter model and a QRP 10/20/40 meter version.  The 10/20/40 is especially popular with portable ops, particularly where CW is used.  Once the resonance point is established, they have a very wide range and height or mounting method doesn't seem to affect them that much, with the exception of the 10/20/40 which has a narrow 40 meter bandwidth of 100 kHz.  I especially like the 10/20/40 because you can take the resonator off, and use other bandwidths by cutting some wire to a half-wavelength and fastening it on.  Multi-band use with one balun is an attractive feature.  Mono bands have very wide bandwidths, up to 700 kHz on the 10 meter model.  One reason why these antennas are so popular is because they only require one attachment point in the air. I typically use mine as a sloper.  Tie it between two trees and you have a flat top dipole.  Use it as a sloper,  Hang it vertically out of a motel room window, or use it as an L.  It's one of the most versatile antennas made.  The quality of the EndFedz is first rate, very well thought of in the ham radio community.  With the 10/20/40, keep it to 10 watts for PSK, as it is full duty cycle.

Whether or not you use a balun is up to you.  I have a small Balun Designs QRP balun that comes in handy for dipoles.  EndFedz come with built-in baluns.  Some people don't even use baluns, especially for QRP, while others use an air choke balun (uses a lot of coax).  I use a modification on the conventional way to have a multi-band antenna.  My QRP balun has wing nuts, and I cut several different bands and put end rings on them.  It's super easy to just unscrew the nut and change bands.  Being mono band, there is no bulk or tangle factor associated with band jumpers, and they are easy to tune the SWR for.  The QRP balun is very small.  Obviously, a full sized balun will not work for portable, unless you drive to the location and use it like a base antenna.

Two antennas that are popular include the Buddipole and Buddistick.  Both offer multi-band operation and are extremely versatile.  The Buddistick is a vertical antenna with one counterpoise that supposedly when matched with the coil clip to have resonance, doesn't need any additional wires.  The Buddipole can be configured in a number of ways, including vertical, sloper, L, dipole, etc.  For serious portable and DXpedition users, the Buddipole is very popular.  The good thing is that no trees or buildings are needed, like a dipole would require.  Chris is very helpful in answering questions, and Budd can often be found on the radio, discussing the various applications of his antenna design.  Chris now runs the company.  Chris is usually in the Buddies in the Caribbean videos on YouTube.  My main gripe is that by adjusting the jumper clips and length of pole arms, it requires a bit of trial and error, and certain bands can be difficult to get the SWR adjusted on.  I've read where most people like to use an antenna analyzer with them.  The Buddistick runs about $139 for the bare-bones basic model.  The Buddipole basic kit is $199.  However, to do what is shown in some of the photos, or suggested configurations requires additional components that can easily raise the price by over $100.  However, if I had the money to spare for a Buddipole, with accessories, I would purchase one.  That noted, I like dipoles.  They are inexpensive for homebrew versions.  Even if you prefer to spend the money on EndFedz which range from $52 to $95, purchasing one or so a year is workable, particularly with a credit card or PayPal.  Cut them once and use them.  And finally, there are probably some homebrew or other types of antennas suitable for field use that I can't think of at the moment.  One last note: For VHF/UHF use in the field, Arrow II sat antennas and Elk Log Periodic antennas are the way to go, for portability, durability, and quality for the price.

Radios obviously need a power supply to work.  Radios which can run on a low power drain (such as homebrew QRP CW kit rigs, FT-817, and others) can use regular batteries.  The 817 even has an option of a built-in battery or a battery tray.  A built-in battery doesn't last that long in the field and drops the power output down automatically.  This can be a consideration if you are planning to do phone, have lousy band conditions or lots of stations on the air.

Sealed Lead Acid Batteries (SLAB) are popular.  Examples would be a fish finder battery, lawn mower battery, etc.  They are very affordable.  Cabela's outdoor supply has an 8 amp hour (Ah) model that receives great reviews, and costs about $25, which includes a charger.  Two batteries with the charger costs $55.  Other brands can cost and weigh more, and you can get much higher Ah ratings.  Yes, they are a bit heavy for multi-day trips.  But, for a short hike, over-nighter, or a day trip to somewhere that doesn't have power, they are a very valid consideration.  Getting to your destination by four wheeler, canoe, etc. can make these batteries a very good match for your radio.  By turning down the power, most rigs will run a long time with one.  We like to car camp at primitive campgrounds that don't have power supply lines.  The SLABs allow operating from a comfortable picnic table, or lawn chair.  Like everything, a bit of commonsense comes into play here.  Take an 8 Ah SLAB and key a 22 amp draw radio, and it won't last long...  Turn that radio down to about 5-10 watts output, and now the SLAB will go for a long time.  For times when I can use the vehicle battery, I have battery clips with power poles, where I can just hook my rig up to the battery.  I can use 100 watts if I need to from this strong of a power source.  This directly relates to portable use, because whether you prefer low power or high power, phone or CW or digital, this significantly affects your need for power.  Does QRP do as well as higher power?  Band conditions, location, antenna and pileups have a lot to do with it.  I've gotten out with 5 watts, and never could get a station with 100 watts.  It depends on variables.  One additional consideration is that both CW and digital modes are full-duty cycle, so low power is a necessity.

Another popular battery is the A123 lithium polymer, made by Buddipole.  Prices range from $65 for a 2.3 Ah model, up to $265 for a 9.2 Ah model.  They are becoming very popular and are built solid, with thick heatshrink wrap, power pole connectors, and a self-resetting internal switch to prevent short circuits.  This a real concern for portable use, where you use slide on connectors or alligator clips, etc.  While I'm on the topic, Anderson Power Poles are a must-have for ease of use.  Hook them up in the ARES configuration, and they can be used with other power poles in the same configuration without sliding them apart.