Finally, portable and digital

This weekend, I tackled the last functionality I normally would use in the field: logging and the use of digital modes.

Out of the box, the 7100 support ASFK keying for RTTY and PSK, but I hadn’t gotten that functionality working yet. So early in the AM in the JARTS RTTY contest I decided that now is the time.

I dusted off an HP Stream 7 tablet running windows that I bought back when I worked for HP and dug out a USB mini cable and plugged it in. The Stream 7 will run 32 bit Windows 10 and has enough horsepower to do the decoding of the digital signals. It is also very small and cheap. I downloaded the drivers from the ICOM site and quickly was able to get the receive and rig controls working (bringing up the radio’s filters and centering signals…) I was using an old copy of MixW, I bought about a decade ago. I fall back on this program since it handles contests great and you can manipulate any of the rig control codes directly in that program, if they are not directly supported.

But when I went to transmit, the rig keyed up but no power output?! It took a bit of digging but I soon realized there was a setting that had to be changed to make the single sideband digital mode (USB-D) pull the transmit sound off the USB cable. They setting can be found at: Set-> Connectors ->Data MOD -> USB. The default is to have the data signal come from the ACC connector in the back of the rig. Once that was done: voila – a portable digital contest station.

Here is a picture of the PC, the radio head and a folding Bluetooth keyboard, operating outside my house. If you look close, you’ll see a RTTY signal on the MixW display.


#amateurradio #hamradio

The portable ‘shack’ in the field — and the need for a keyer

I took the completed portable shack that I’ve been working on into the field last weekend. It was all setup and working in about 15 minutes. I was on for about 4 hours on 17 meters and talked to about 15 contacts across 3 countries on SSB. I was focused more on playing with the settings and options than actually making contacts so I was pleased with the performance, overall.

I did realize there was one thing I wished I had and that was a disposable iambic keyer. I have a nice keyer at home for sending Morse code, but there was no way I was leaving it in my portable shack box or (more likely) forgetting it at home so it wasn’t there when I need it. Once again, it was time to call on the 3D printer.

keyI came up with a design fairly quickly that used about a dollar’s worth of spare parts I had lying around and half a hacksaw blade. I printed out a couple of samples to refine the model. By the time I had the second one done, I declared victory and now have a small iambic keyer. It is a simple keyer without squeeze functionality, though there are some designs out there that do that. The only real refinement I’d make is to create a tunnel in the base to run the wire through, rather than using a zip tie on the post where I screw down the hacksaw blade. We’ll see if it is ‘good enough’ in the field, next time. I’ll likely screw it into my clipboard.

If you are interested in the iambic keyer design, I uploaded it to: thingiverse

Some people probably find it hard to believe that there are still folks that operate CW, but it has its own challenges and can get the message through when little else can. I used to operate CW a great deal, but am a bit rusty now. We’ll see if having a keyer like this helps.

#amateurradio #hamradio

HF station in a box – bringing it all together

20160926_054601I looked for a number of different cases that I could carry around all my materials to operate portable and after a few trips to the hardware store, I settled on a mobile tool box from Stanley. The 3-in-1 mobile work center was not the sturdiest tool box I could find but it did have wheels. extended handle and a separate compartment for the battery.

I was able to configure the 3-in-1 to contain just about everything I would need to operate for a weekend.

20160926_054422When I started working with the tool box, my first concern was a safe place to put the battery where it could be secure and not move around. Since it is the heaviest component of the setup, it had to be on the bottom.

I choose to create a set of X-spacers (out of wood) that would both keep the battery stable as well as ensure that there was sufficient clearance over the battery to protect the cables. It did waste some space, but since I’ll still have access to the compartment, I can use the space if I needed.

20160926_054521Though it is a bit hard to see, I also 3D printed a shim that keeps the battery wedged in there tight.

On top of the battery layer, I created a shelf that held the circuit mentioned in last week’s post as well as the radio itself. The shelf was also fashioned out of wood. The most difficult portion of this part of the build was figuring out how to wire that voltage/current meter, since it came with no instructions and the wire colors were a bit non-standard. I figured it out after watching a youtube video and a bit of trial and error. Overall, the installation came out about as well as I could have hoped.

The shelf can be quickly removed, so I have access to the battery, when it needs to be charged – since I was too cheap to address that issue yet.

radio-mountIn order to mount the radio securely, I 3D printed some brackets (shown in the photograph above, as well as the model on the left). Although these were made out of PLA plastic, they seemed to be sufficient for the job. One of the nice things about PLA is that it is relatively easy to warm up the nuts and then sink them into the plastic, so the nuts are held in place when you bolt them down.

20160926_054623The top section of the tool box contains the antenna analyzer, radio head, headphones, computer and all the other materials required to operate. I definitely need to work on getting that equipment organized, since right now I just threw it all in the box.

I should get a chance to operate this weekend and give the setup a real endurance test.

My next post should be about that operating experience and the computer I used (assuming I get a chance to operate digital modes and the conditions are right to compete in a contest).

#amateurradio #hamradio

Circuits – shocking, it’s starting to come together.

Now that I have a battery, I need to wire it all together. I plan on using a circuit like:


I’ve had a very busy weekend that kept me away from working on my portable design much. I was able to stop by HRO and Frys and get the rest of the parts I needed.

My next entry will dig into selecting a case to haul this gear around and some quick and dirty mounting of the circuit shown. I’ll likely build something out of wood and 3D printed parts initially and think about a more permanent solution if that attempt doesn’t turn out to be good enough.

Not sure when that will happen, since next weekend will be keep me even busier then the last. Hopefully, I’ll have it all done by the end of the month and I can take it with me to the Belton hamfest.

Portable power for a ham station

Regional 2016 National Preparedness Month Logo
National Preparedness Month 2016

This post is the 6th in a series – Especially since this month is national preparedness month, investigating off-the-grid power is my next stage of going portable. I’d like to have something light, rugged, safe, cheap and that can run my ICOM 7100 for at nearly a day (but not at full power). There are clearly going to be some compromises involved in this choice.

I settled on 35 Ah battery as my benchmark to cost against. An amp-hour is the ability to pull one amp for one hour, or 10 amps for 1/10 of an hour… It’s not quite that simple, since you can’t pull too much power from certain kinds of devices reliably. If you have a device that pulls 20 amps, and you use it for 20 minutes, then the amp-hours used would be 20 (amps) x .333 (hours), or 6.67 AH. Therefore, if you plan to transmit 20% time on HF: 20 amps x 0.333 hours = 6.67 amp hours and on receive the radio pulls 1.5 amps x 0.66 hours = 1.0 amp hours that means the radio will consume almost 8 amps in an hour. My ‘back of the napkin’ calculations say: I should be able to operate for about 4 hours at higher power levels.  Sounds like I better plan on having an amp meter in my circuit if I want to have predictable usage.

For batteries, there are a number of possibilities in the marketplace:


Rugged Safe Cheap


Traditional Lead acid





+ + OK








+ +



This table is based on some quantitative analysis but I’d call it primarily a qualitative perspective. Feel free to comment with better info if you find have it.

The decision

battery-51tnl6zn1rl-_ac_ul115Since I don’t know how often I will use this portable solution yet, I didn’t want to invest in higher cost batteries or solar recharging… They’ll be time for that later, if I become addicted to being in the field. Right now I just wanted something ‘good enough’ to be usable and get started, so I went with the AGM solution.

Other considerations

Once you go with a battery based solution, you need to think about charging. Do I want to have a solution where I can switch over to battery if there is a power outage or will I depend on remembering to charge the battery before I need it? Although the switching option is appealing, I think I’ll hold off on that as well since it should be easy enough to add later.

How about connecting to the various devices? I want something flexible, standard and commonly available. I convinced myself that Anderson Powerpoles from Powerwerx are the way to go. Besides there is an HRO in Plano (near my house and they have a huge selection of options).

Next time, I will cover the circuit and configuration I ended up putting in place, as well as what Powerpole based options I purchased to get started.

Humor you may get a charge out of:

Did you hear the one about the radio operator arrested for battery? The charges were dropped because he only resisted a little.

#natlprep  #amateurradio #hamradio

The initial portable operations test

antennaThe first field test of the radio and antenna went off successfully. Though the VHF contest was a bit of a bust, I did make one contact on 6 meters that was 138 miles away. I looked on line at 6 meter band propagation and didn’t see much going on – so I gave up and reconfigured for 17 meters.

It was fairly active and I talked with a number of people including one in Belize and on in Canada north of Washington state. He was also portable and had been trying the VHF contest but also gave up – that made me feel a bit better.

I did learn a few things to address before next time. My list of essentials now includes:

  • Antenna analyzer
  • Power inverter (may not need this, but I have one so I might as well include it)
  • Extension cord
  • Power strip
  • VOM
  • Flashlight
  • Line or rope
  • Towel
  • Pencil
  • Clipboard
  • Cigarette lighter to USB adapter (anything to keep a phone charged is a good thing)
  • A towel
  • Bungie cord
  • Empty milk jug or similar – this is great ballast to keep the antenna from falling over (see above).

Below is a picture of the setup I was working from. It was 92°F but not too bad in the shade. As you can see, I am operating using a 1970s era power supply, so power is my next dimension to tackle. Closely followed by my solution for carting all this around effectively.


Next step in my quest to be portable – the antenna

The antenna is easily the second most important component of a portable station and unfortunately it is also the area that is most easy to compromise on. I wanted to have one that would support multiple bands and yet still be small and flexible enough to carry with me and set up in minutes (by myself).

There are a number of types of antennas that may fit that bill:

  • A long wire – They are low cost and easily to transport but they require an antenna tuner, lots of room. They are not all that easy to set up, since you’d need to be in location with tall structures or trees and some way to get the wire into the air.
  • A multiband wire antenna (like a G5RV) – These have some of the same issues as the long wire although they shouldn’t require an antenna tuner.
  • Mobile antennas – Little verticals are easy to switch out. Carrying around the various antenna resonators to support the bands would be a bit unwieldy. Verticals can be set up quickly but the costs can quickly add up if you want to work on multiple bands. Small verticals like this are always a compromise on performance as well. An alternative is a screwdriver antenna that adjusts to support multiple bands.
  • Buddipole – I’ve known a number of hams over the years who have purchase these. They are not cheap but they do work on everything from 40M up through 2M with the default configuration. They are light (9.5 lbs.) and easy to carry. If you get the deluxe package, you get a tripod to mount the antenna on and pretty much everything you need. The antenna can be set up in minutes and it seems like the ideal solution for my needs.

I am sure there are others that I’ve missed but those are the alternatives I investigated.

I eventually ended up getting the Buddipole and hope to put it through its paces on the September VHF contest this weekend – more on that later.


Just to round out this post about antennas I’ll add: I heard the other day about two antennas getting married. The wedding was nothing to call home about, but the reception was amazing.