Thanks Bob, great info!

I figured that on 80m, losses can have an impact. Not like on 20m.. The band is noisy and every bit helps.
I might have to rethink my potting plans then.. Maybe something closer, like closed-cell foam.
My idea was to find some kind of mylar for extra insulation between the coil and the case.

Gil.

QuoteEstonia!  Cool!  Now you know where you can check in to find out if the Zombie apocalypse is worldwide!.  LOL

You're never too careful  :o

I fixed it! I wrongly swapped two capacitors because of some confusion in the old (a new one was was published) building manual. Now, with a 10V supply, I get 4W on 40m and 3W on 20m. Still a bit low on 20m, but if I use a 12V supply, I should get decent power. I am glad it was something simple, because those capacitors have no markings on them. If you don't know where to look, it can be a nightmare; as in unsoldering them all! Which for SMT components is not easy. I decided to try it on the air right away and called the first guy I heard, in Germany! I got a 449 report. Not bad for a 5000 miles QSO on 4W!

I love the MTR! For a trail radio, there is nothing better. It weighs almost nothing, even with the steel case. It's a keeper for sure.

There is something special about using a radio you built yourself, especially if it was difficult. The MTR is definitely not a beginner's kit. It took less time but was harder to build than my K2. It is also amazing to talk to someone 5000 miles away with a radio that fits in a shirt pocket or an Altoids box! How crazy is that? And not just by chance, regularly!

Ya'll have a great day  ;D

Gil.

QuoteI have narrowed my list down to the Yaesu 897 or a KX3.

I have the KX3. I don't think you can find a better radio! Especially if you want it portable, low current drain. In a SHTF situation, you'll appreciate not having to carry heavy batteries and having the small one you'll be using last a long time..

If you don't do or never plan to get into CW, then the choice is harder, though I'd still go with the KX3.
If you do CW, then there is simply no contest at all.

Gil.

I love end-fed antennas. My first one was a PAR 40/20/10, and is has become my permanent antenna at home. I have reached 5200 miles on 1.3W and 830 miles with 100mW with it! And numerous other such contacts. I also have a tunable 6-40m I built, and am getting a 15-40m end-fed tuner kit in the mail this week. Why end-feds? Because they work, really well. They are easy to deploy in the field and weigh very little. LNR Precision (bought PAR) has a new trail model by the way: http://www.lnrprecision.com. But this is about building your own 80m version. I wanted something rugged and simple. An end-fed is simple by design, though the theory isn't so simple. It is an impedance transformer. Here is the schematic I found online (http://www.spirat.com.au/vk5zvs/pic54.htm):



Not much to it really... Let's see with all the components in the box:



The box is a Hammond cast aluminum. The capacitor is a 100pF 3500V doorknob type. I could have used a cheaper ceramic disk type, but you know me by now.. The resistor you see there (black) goes to an isolated ground plug for use with a weather balloon or kite (1.5M 3W). When connected to the earth, it bleeds static electricity to the ground to avoid frying the radio (thousands of volts).

And the finished product:



I though about connecting grounds together via wires, but the box does that well.. The optional counterpoise (we'll see about "optional" later.. (0.05 WL, about 13ft)) binding post (black) is electrically connected to the box, while the antenna wire post (red) of course is isolated. The magnet wire is 18ga. Opinions?

After testing I will pot it with liquid rubber... I did some preliminary testing with a 135ft wire strung around the house and got a 3:1 SWR; just enough to send my call sign and "testing" in CW of course. I very rarely use a microphone.. Higher up the band the SWR goes up, so the antenna is a bit too long. Having many turns at weird angles and a house with all it's wiring around it of course doesn't help. Once stretched outside I expect it to work great. I will post an update.

Now I'll be able to check in CW nets on 80m!

Gil.

Hello Chris and welcome aboard. Thanks for the offer. Enjoy the board a bit and then you can send a small donation... The hosting will stay where it is, for a number of reasons. I do have my own server as well, which runs FreeBSD. I do server setups, PHP and MySQL, everything on Unix. I wouldn't touch Window$ with a ten foot pole, too unreliable. So, all set on that front. Radiopreppers is hosted in Iceland, being an international site, not only for the U.S. FB on the KX3, I have one too  :)

Gil.

Hello,

You guys check in on antennas board, I have a Slim Jim antenna described there for 2m, which works great!
Actually, here it is: http://radiopreppers.com/index.php/topic,4.0.html

Gil.

Well, even though I am still only putting out 1.2W on 40m, I hust has a 5200 miles QSO to Estonia with the MTR! Antenna is the PAR (LNR) End Fed.

Gil.

Thanks again Ray for your help. If only my paddle didn't decide to misbehave.. Must be dirty contacts as you suggested..

The MTR is alive! I will post photos and a video soon. Soldering some chips was a real challenge. I didn't think it would actually work the first time out. One segment of the LED display was out, I had forgotten to solder that pad. I do have only half power on 40m, and need to troubleshoot it. The receiver is pretty sensitive, the sidetone sounds good and the 500Hz filter works great.

Did you say S7 Ray? That's pretty good 800+ miles away.. Well, 3W is 3W.. I would probably get about 4.5W at 12V. I used seven AA batteries. I have a 13.8V power supply at home, and might put three diodes in series to get 12V (3x0.6V drop). For the field, I have eight-AA battery holders and 1.2V cells. My solar panel should arrive this coming week.

I can't help but compare the MTR to the PAR Mantiz. Both great radios. Of course the Mantiz is available, while the MTR rarely is. Band choices can be debated all day. The MTR covers two bands out of 40, 30, 20, and possibly 80m. The Mantiz is 30/40m. Tunnig is of course easier with the Mantiz which uses an encoder and has an LCD display. The MTR uses switches and has a one-digit display. Either way, it works. Better than I thought on the MTR. Power is similar. The Mantiz has variable filters while the MTR has a fixed 500Hz filter. The Mantiz filters however can't be centered precisely. The MTR also does not have a SWR meter like the Mantiz. Both rigs have a memory keyer. The MTR is definitely smaller; it also draws slightly less current. The main difference between my Mantiz (sold it) and the MTR is that I actually built the MTR! There is a certain emotional attachment here.

I recently read "Three Hundred Zeroes" by Dennis R. Blanchard, who actually carried an A.T. Sprint (Steve Weber design) CW QRP rig with him on the Appalachian trail. He did meet Steve Weber on the trail.. Turns out, the author lives in my town! We exchanged a couple emails and might meet some time after a big European bicycle trip he is preparing for.. What are the odds!? Anyway, my point is that for trail hikers, weight is an obsession. Every ounce saved it seems does count. That is when having a small CW QRP radio does pay off handsomely. A lot of remote areas of the United States, not to mention the rest of the world, do not have cell phone coverage. The maximum pack weight suggested is 20% of body weight. For me, that means about 38Lbs max. That isn't much. Imagine carrying a 10AH SLA battery, maybe a KX3 or FT-817ND, plus antenna.. That's a big chunk of your allocated weight there.. Of course people will say "I'll never have to carry a heavy backpack because blah, blah blah.." How do you know? Hope for the best, prepare for the worst.

Gil.

I thought about getting one...

Of course I want everyone to get into QRP CW! Hehe... Every ounce counts when you are on foot. Look at extreme hikers.. Some even cut their toothbrush in half to save weight. In a "teotwawki" situation, we would soon all be on foot..

Gil.

The MTR arrived today! Man, that thing is small... The case, made by TenTec looks great, though a bit thicker than an Altoids box. I was going to sell it and use an Altoids, but changed my mind and will use it. I could step on it with no ill effect.

I started the build using my soldering station and a fine tip. The resistors went on first, then the capacitors. It took me exactly four hours to install them all. It is actually faster and somewhat easier than through-hole components, except for the size. A good magnifying lens is a must. When I say "a must," I mean that you can't build without one. Also a plus is the fact that you don't end-up with a bunch of component leads on the floor.. One thing you absolutely need is a steady hand, otherwise, forget it..

I plan on one or two more sessions to finish it, by Monday, I am sure. Have a look at the attached photo.. The PCB (sorry, it's upside-down) shows the bottom side, with all resistors and capacitors installed (yes, there are many components on that board, look closely!) The coin is a penny. The tiny black dot below the coin is a resistor!

Those chips are going to be a real challenge to solder..

TGIF!

Gil.

I don't have it yet, just ordered it from Amazon... I will let you know though.

Gil.

That's what I just decided to go for, AA rechargeable NiMH cells. I ordered a Goal Zero 7W solar panel with their four AA battery holder. This way I can recharge four AAs at a time, four or eight per day depending on conditions. My rigs use eight AAs, but they will last a few days when full. I can use AAs for flashlights and other devices as well. the Goal Zero battery holder also allows charging USB powered devices like my tiny powered speaker and iPod.
I was going to use LiPo batteries with a special charger, but the price is much higher. The other advantage of using rechargeable AAs is that if for some reason you can't charge them, you can always buy regular disposable batteries.
My 2.9Ah SLA battery is great, but a bit heavy (3.3Lbs) for hiking...

Gil.

All right then... On top of this MTR build thread, I will post a "Radio Camping" thread on the tactical board. It will include all the gear I will be using, including tent, backpack, stove, solar panel, batteries, QRP rig (MTR), Antenna (End Fed), and whatever else I find relevant to operating in the boonies. I just ordered a BetterQRP (http://betterqrp.com) End-Fed-Half-Wave tuner and will try to duplicate my PAR End-Fed, which is semi-permanently installed at my house. I am also building an 80m end-fed matching box, but I will probably not take my KX3 with me, so that will be another thread. I will most likely mount my American Morse DCP paddle on the MTR enclosure.

The MTR should arrive tomorrow or Friday. I will probably post videos as well.

Gil.

QuoteDo you have a bunch of them or a few larger cases?  Do you have enough for everything?  You were on the Faraday cage thread, so do you simply drop your faraday caged items into a Pelican case or vice versa?

Hello,

I have one for my K1 and getting one for my KX3. I also have one small one I can use for smaller rigs, but it is used for something else right now.. I use them for transport. The Faraday boxes (cookie tin can) stay home. I might get Faraday bags for inside the cases.. So, not quite enough for everything yet, but getting there. I'll probably get a small one too for my Weber MTR. The small ones are quite affordable, however prices go up quickly for the bigger cases. The biggests one is my Pelican 1400 for the K1, but it also contains a battery and key.. The 1200 would have worked for the K1 I expect. For the KX3, I am getting the 1150, which is just big enough for a tiny key and microphone, but nothing else, which is all right since the KX3 has space inside it's case for batteries. My Yaesu FT-270R handheld, I won't bother with a case.. I probably won't even take it with me camping anyway. A small CW radio is enough for me.

Gil.