KX3: Cool Go Box

I just came across this on the internet the other day, but I thought it was a very cool way to package the KX3 for portable operation.

Check out www.oe2atn.at/tom/gobox

If  someone would commercialize this, I think it would be very popular.

SMD Project

I finally took the plunge. I am just getting back into building my own radio gear after a few years off the wagon operating primarily QRO commercial gear. As I have built gear in the past, I found it very satisfying to put something together that works and then use it to make QSO's. However, while I was away from the kit building scene there was a step change in the technology of radio components and the methodology to build them, that is SMD, (surface mount devices). These are very small capacitors, resistors, diodes, etc... that greatly reduce the size of whatever you are building. Let me repeat, very small. They are tweezers and magnifying glass kind of small. I would say simply, that I was very intimidated by this change. However I wanted to learn.

When Steve, KD1JV, kitted another run of his MTR (Mountain Top Rig), I wanted one. It is however an SMD kit, but I thought why not take the plunge. However when the kit arrived with its cool looking case and I looked at the components I thought maybe I should have someone else build this kit. I didn't want to ruin such a cool radio with my learning mistakes. So I outsourced that one. However, I still wanted to learn SMD construction. Somehow I felt like a QRP wimp because I couldn't build SMD projects. So, what to do?

As I searched the QRP kit world, I found the perfect project. The SMK-2, a kit from Doug Hendricks, www.qrpkits.com, is a 300mw, 40m crystal controlled transceiver. It is specifically designed for SMD training. So I ordered the kit.

SMK-2 SMD Kit

There are a couple of methods to build SMD projects that I wanted to try. The first is the solder paste, hot plate method. To be brief, you put small amounts of solder paste on the component solder pads and then place the components on the pads. You should use a syringe to apply the paste.  You can do this with as many components as you feel you can keep in place. It is a delicate operation but when done properly can save a lot of time. You should only have one "cooking' if you will, so put as many components on the board this way, if not all, as you can. I chose to do a few of the capacitors. After applying the paste and placing the components you put the board on a cooking griddle set at 200 degrees F. When the solder paste starts to smoke you use a hot air gun, (available at hobby stores or with commercial SMD soldering stations), and direct the hot air at the components. Before your very eyes the solder adheres and makes a very nice looking solder joint. When completed, let the plate cool before removing the board.

After I let the board cool, I wished I had set more components in this manner as the joints looking almost professionally done. However, I wanted to learn to hand solder these small SMD as well, so I would have plenty of  small parts to practice on.

Hand soldering requires some magnification device. I use a relatively cheap, lighted magnifying lamp like the one below. It is a 2X glass with a small 5X circle that you will need to identify parts.

You will also need some tweezers to hold the components during the soldering operations. The hand soldering process is as you would suspect, tin one pad, set the component and then tin the second pad. So far, with the right tools, the hand soldering has been much easier than I suspected.

I haven't finished the project yet, but have put down the capacitors, resistors and diodes, so the bulk of the work is done. One thing to be aware of, try to do the work where you can find dropped parts. I dropped a resistor onto the carpet in my shack and had to use a nylon trap on a vacuum cleaner to find it.

I will let you know when I pass the smoke test.

Project: KI6J SOTA Tuner

As I have written I am building up my QRP and SOTA arsenal, focusing on portability, efficiency and weight. While weight and portability are obviously desirous for  your primary station configuration, I like to have some redundancy in case Plan A doesn't work. For example, I prefer resonant antenna's, but resonance in a given configuration in the backyard may not always equal resonance in the configuration you end up with in the field. So, I like antenna options.

With that in mind and a need to build something I opted for the KI6J SOTA Tuner as part of my back up antenna system. I haven't built anything in a few years and wanted to get back in the groove on melting a little solder, so I ordered the kit from Stu. Relatively speaking it is an easy kit to build. You do get the pleasure of winding a small transformer and toroid. However if that scares you as a new builder this is a great kit to learn on.

This kit is designed for use by portable QRP operations needing a lightweight, easy to deploy antenna system. Using this tuner, a portable station needs no ground radials and little or no feed line to achieve excellent results. The tuner matches the impedance of end fed, half wavelength (EFHW) wires on 40m -15m and contains a built in SWR indicator. The tuner is designed for durability and reliability of operation and handles QRP power levels, 5W CW and 10W PEP SSB.

KI6J SOTA Tuner

The build went very smoothly and when I finished, it didn't work. Wait a minute this is an easy kit, no solder bridges, correct number of turns on the toroid, continuity in the circuit, what could be the problem? So here is a lesson, always read the addendum or errata, or whatever the kit designer calls it, that amends the original building instructions. My problem, I soldered the LED in backwards, which was clearly explained in the addendum that I failed to read. So, I reversed the LED and the unit worked like a charm.

SOTA Tuner

Not a bad Toroid

So, to the field test. I found a piece of wire, roughly 1/2 wave on 20m and put it up on my Jacktite mast and hooked it up to the SOTA tuner. I found resonance on  40m -15m just as advertised. I love when a plan comes together, especially when the plan includes something that I built myself.

Needless to say , I recommend this kit and Stu supports it very well, by asking questions like, "did you put the LED in backwards?" Plan B is now ready to go.

The kit is available at: http://betterqrp.com/ 



The RockMite And Then Again It Might Not

So I just finished writing a post about frustration being ultimate reason that many hams can't stick with QRP. Many have high expectations, some  are unreasonable expectations that can't be met. When I last wrote of this I was declaring my optimism. Well, I have crossed over into the state of frustration.

Years ago I built a Rockmite. It is a fun project. When I finished it, I didn't take the time to put the antenna connector on it or the dc plug, I simply use alligator clips to get everything working. I remember calling CQ for a few minutes made a QSO, which the station on the other end actually recorded to let me know how my 400 mw sounded. Pretty cool and this milliwatt stuff isn't all that bad.

While cleaning my shack a few years later, since I had never used the RockMite since that first QSO, I threw it away. The day after the garbage man took it I'll admit I was a little remorseful. Ever since I have been watching the auction sites for a Rockmite to replace it. I didn't want to go to all the trouble to build another one, I just wanted one to have and play around with occasionally. The other day that replacement arrived at the house. I hooked it up and called CQ for an hour, some of you may have seen my spots on QRPspots.com. A few guys tried to hear me but couldn't. Today I came home from work and hoped to make a QSO with a local during the afternoon and called CQ for another hour. Lastly I tried again tonight. No joy. Probably 2.5 hours of CQing with the Rockmite and no QSO. So it is a little frustrating. What else could I have done with my life during those 2.5 hours. After calling so fruitlessly with a QRPp, rock bound rig, the KX3 now looks like a QRO rig.

Oh well, I'll try it again. QRPp is a little like fishing, they might not bite today, but they might be tomorrow, at least that is the optimistic way to look at it.

RockMite