Saturday, June 24, 2017

Measurements

Recently there was a discussion on Facebook about a new radio with low power output. "A reading is not a reading" and it is seldom absolute. 



Keep in mind just looking at the reading on any instrument doesn't tell you the whole story. You need to understand a little about what you're measuring and what you are using to do the measurement. It's also important to understand why you are making the measurement. I offer these terms as food for thought:









Accuracy – designates how close a measured value is to the true quantity of what is being measured. Without comparison to a standard, accuracy cannot be determined. It's often specified in terms of being +/- some percentage of the indicated value.
Repeatability – describes how well a system or device can reproduce an outcome in unchanged conditions. In some applications, repeatability is more important than accuracy. If the system is repeatable, an error can be mapped and compensated for.
Resolution – is the smallest increment the system can display or measure. A system can have a high resolution with poor repeatability and accuracy.

73

Tim N9PUZ

Monday, June 12, 2017

A KX-2 Has Landed

Serendipity is sometimes my best friend. A couple of weeks ago while doing some random searching I stumbled upon a lightly used Elecraft KX-2 portable rig with most all of the desireable options. It included the radio, internal battery, autotuner, real time clock, and the carry bag plus an assortment of cables and adapters. A KX-2 has been on my wish list for a while and this was too good a deal to pass up!

















To keep the new rig in good shape I added the protective handle and heat sink shown in this photo from the Pro Audio Engineering web site. If you add these to your own KX-2 I recommend reading the directions a couple of times and really studying how it all goes together. It's not especially difficult but there isn't a lot of extra space in this rig and you need to be prepared with some small tools and a steady hand!

I'm still learning the various features and controls at this point. It's been on the air from my home shack as well as backyard portable. It's a very impressive radio so far and you'll be hearing more in the future.

73,

Tim N9PUZ

Monday, May 22, 2017

N9PUZ on the Missouri SOTA Web Site

Just a short update. My friend John Watkins is the W0 SOTA area manager here in the US. He recently published a short piece I wrote on the MO SOTA Web Site. The site in general is a good resource, particularly if you're planning portable activities in Missouri.

73,

Tim N9PUZ

Sunday, April 16, 2017

A Trail Friendly Single Lever Paddle

If you are like most hams who work CW you probably have more than one key or paddle. You may even have an entire collection of keys and paddles. Well, I don't consider myself at the collection stage but I have a few and while my nicest small paddles are probably the Palm Radio Mini-Paddles, they still weren't exactly what I wanted. I wanted something smaller for portable work without paying the price for their Pico Paddle.

Full Disclaimer: I am not the world's greatest CW operator. Unless I can give it my undivided attention I still struggle. However, I am slowly improving and I certainly enjoy it.

Recently I ran across the web site for QRPGuys. They have some interesting items in general but one that caught my eye was their Single Lever Mini Paddle. It's intended to be built into a project of your own, a kit, etc. but one look and it just spoke to me. Actually, it said "hack me"!


The single lever paddle is a cleverly designed kit. It's made of some pieces of printed circuit board and a few common hardware items. It's small to begin with and best of all the cost is just $15.00US!

If you decide to built one of these read their very good directions and be careful to follow them. The kit is easy to build but I imagine it would be very difficult to unsolder the pieces if you hurried and made a mistake. Working carefully I spent about 45 minutes getting to the state shown in the photo above.



My idea for the hack, pun intended, was to remove the mounting ears where the paddles would normally bolt to the outside of your project enclosure. The small remaining paddle could then be attached to a clip board, top of the radio, etc. using a small square of velcro placed on the bottom of the paddles. The bottom PCB provides an adequate piece of real estate for doing this.



When you're finished you'll need to attach a connecting cable directly to the printed circuit boards to make your connections. As luck would have it I am out of small 1/8" stereo connectors so I have no photo of the totally complete setup. Here is a top view of the completed paddle. The main assembly is about 1" by 1" by 5/8" high. Total depth with the lever is about 2".


I hope this gives you some ideas of your own!

73,

Tim N9PUZ

Friday, April 14, 2017

April 2017 SOTA Trip

In April of 2017 Teri and I went to the Ozarkcon QRP gathering in Branson, MO. On Thursday and Friday before the event I joined John N0EVH and Frank KD0MQO to activate several SOTA summits in Arkansas. We had a great time over two days. I activated four summits with them and the two of them did a fourth on their way home on Sunday. The weather was fantastic and the scenery was awesome. Many thanks to all the chasers. We easily made the minimum contact count at every summit.























Frank N0EVH was our leader. He's also the W0M area SOTA manager!




















Frank KD0MQO had a guest OP on Sunday.













Finally, yours truly Tim N9PUZ. In this photo I was test driving John's Elecraft KX3. Nice rig!




















There's always something unexpected in the field. At Boat Mountain we had some really severe local QRN making it tough to hear the other stations for a few minutes!










I thoroughly enjoyed this trip. As this was my first time as a SOTA activator I'd like to thank John and Frank for their hospitality and guidance in making this a successful trip. A word of caution: Playing radio outside is very addicting. But, I highly recommend it!

73,

Tim N9PUZ

Sunday, March 26, 2017

Xiegu X-108G HF "Go Bag"

Over the winter I purchased a Xiegu X-108G HF transceiver for portable operations. I have an Elecraft KX-1 which is fantastic for "CW Only" operations but a lot of times I like the ability to do SSB and also operate more bands than the KX-1 covers.

I wrote a little about the X-108G earlier in my Winter Field Day post. The basic info is it covers 160M to 10M (AM, SSB, and CW) and has power output which is adjustable from 0.1W to 20W. In my opinion reliable SSB operation usually needs more than 5W and I find that 15W or so works really well.


The photo above shows the "guts" of the portable station. Major items are as follows:
*I plan to put some sort of rubber or foam ring around the two buttons on the tuner. I did not notice any problems today but I don't want the pack to hold them down and drain the battery while traveling.

These three items are all mounted to a thin piece of masonite peg board, maybe 1/8" thick,  using nylon zip ties. The tuner is attached to the radio with Velcro for ease of accessing the battery.

This method with the zip ties isn't especially pretty but I've found that an awful lot of my projects spend their lives in "beta test" mode as I constantly tweak and tinker with the designs trying to achieve the elusive "just right" configuration. The reason for the corners of the masonite being chopped off will be obvious shortly.


Everything I need to go portable fits in a small backpack with the exception of my collapsible 28-foot kite pole. The top of the pack I chose is slightly rounded so I trimmed the masonite base so it would fit easily. Although it might be possible, I don't plan to operate the radio in the pack. With higher power comes more heat. I spaced the radio up off the board to provide some airflow but being inside the pack would prevent that from doing any good. Besides I need to get to the antenna connector on the tuner.


Here's the station all buttoned up and ready to travel. The outside pockets of the pack hold the X108G's microphone, a small set of paddles, a 9:1 unun and wire for the antenna. There's also a small notebook, pen/pencil, and a pocket knife for "field repairs" if needed. 

A 25ft length of RG-58 is coiled and attached to the outside with velcro. That length coax provides an adequate counterpoise for the antenna. The coax will actually fit in a thin pocket that is the same size as the entire pack. I ended up putting it on the outside because it was just a lot easier. 

This afternoon when I was trying things out in the back yard with a 30ft wire I was able to get a low SWR on 40, 30, 20, 17, and 15 Meters. The WPX contest was going on and I made contacts on 40 and 20 Meters without any problems.

73,

Tim N9PUZ

Saturday, March 11, 2017

Ozarkcon 2017 Is Nearly Here!





Each year the Four State QRP Group puts on a QRP convention called Ozarkcon in scenic Branson, MO. This year's event will be held April 7-8, 2017.

Ozarkcon is a great, relaxed time. It has a swap meet, a day of presentations, build-a-thon, etc. to keep the fun pumping. Branson has plenty to do for spouses or kids not interested in QRP and best of all since it's "off season", room rates, etc. are very reasonable.

More info on the Qzarkcon Web Page.

73,

Tim N9PUZ

Monday, March 06, 2017

My Humble Station

I'm not sure why but it seems every time I post here, on Facebook, etc. someone always contacts me and wants to know about my station. It isn't bare bones but considering I've been at this for 40 years now I still think it's modest but functional. Note there are no VHF/UHF FM items listed here. I change those too often and in general I think they are mostly a matter of which one you like the looks of the best. HF is my favorite part of amateur radio.

Here goes:

Radios & Antennas

  • - Icom IC-7200
  • - Ameritron AL-811H (seldom used) 800W amplifier
  • - Palstar AT-1K Manual Tuner
  • - 80 Meter Inverted V w/Balanced Line feed.


  • - Xiegu X108G Portable HF Transceiver (20W)
  • - Elecraft T-1 Autotuner
  • - End fed wires & 28 ft Jackite collabsible kite pole
  • - Buddipole


  • - Elecraft KX-1 Really Portable QRP Transceiver (40/30/20 Meters)
  • - End fed wires


  • - Assorted novelty rigs (Heath HW-8, Pixie, Rockmite)

Computers and Software

  • - Windows 10 Desktop, Windows 7 Laptop
  • - N3FJP Amateur Contact Log and Contest Logs
  • - FLDigi for most digital modes
  • - WSJT-X for JT65

No, this isn't every piece of gear I own but it's the major stuff. I have a few odd small tuners and accessories tucked away here and there along with some test equipment but I'm too lazy to get all of that out and inventory it. By and large these are the things I use regularly.

73,

Tim N9PUZ

Wednesday, March 01, 2017

The Pixie Lives On!

I remember being all excited years ago with the notion of a 40 Meter transceiver kit that could be had for the princely sum of about $15.00US! I recall buying the kit but never built it. I let it age on a shelf near my bench and ultimately sold it at a hamfest.

Pixie II Kit




















Well, a few years have gone by and the venerable Pixie lives on but in an updated version. While most ham gear has gone up in price the Pixie has actually gained an enclosure and gone down in price. You can buy an assembled Pixie in a case on eBay for around $8.00US as I write this. Oh, that price includes shipping by the way.

Chinese Pixie


















In theory, one could claim that if you changed the crystal to somewhere a Technician has 40M HF privileges, added a simple dipole tuned for the Pixie's crystal frequency, an inexpensive key, 9V battery, and some earbuds a person who puts in the effort to learn Morse Code could get on HF for under $15.00US. While that's technically true I absolutely do not advise this as a plan to get into ham radio cheaply. The reality of the situation is that operating a very lower power transceiver on a single frequency with little to no CW skills and experience would be, in my opinion, a recipe for frustration and disappointment.

None of that of course means you shouldn't get a Pixie. If you have some modest skills or a couple of friends who live nearby it could be a lot of fun. If your operating skills are up for it you can probably make a lot of contacts.

I mentioned changing the crystal. The Pixie comes with a frequency of 7.023 MHz which is in the US Extra Class allocation. While you could certainly operate there as an Extra I'd recommend you switch it out to the more common 7.030 MHz QRP "watering hole" or even move up the band to around 7.122 MHz where there's quite a bit of slower speed CW activity. Things are a lot more casual there.

As for the crystals, one supplier I've had great success with, and who has great prices, is KC9ON's 3rd Planet Solar site. He sells crystals on many of the common frequencies for just a $1.00US each and ships very fast.

73,

Tim N9PUZ


Monday, February 27, 2017

Wire Antenna Confusion

I see a lot of misleading comments about antenna wires fed at their ends. Perhaps I can clear up some of the confusion.

There is a general category of antennas that are "end fed wires". These consist of two basic types. First is the EFHW (End Fed Half Wave) antenna. As its name suggests it is a half wave long and is normally only usable on a single band. It requires a small matching network in most cases. The EFHW design isn't quite as obvious as it sounds. Steve Yates AA5TB does an excellent job of explaining the End Fed Half Wave Antenna.

The second common type of end fed wire antenna, and one I usually use for portable operations, is the Random Wire Antenna. The name of this one is confusing. First off, it is not exactly a random length and second of all you definitely DO NOT want it to be an actual have wavelength long on any of the bands where you want to operate. The reason for this when you feed a half wave long wire at its end the impedance is very high compared to the 50 Ohms we typically want. Most internal radio tuners and many external tuners cannot bring this high impedance down to 50 Ohms which will result in an SWR that is too high for most radios. My choosing a length of wire that is NOT a half wave long on any band where you will operate a good match is more likely. The following article describes how the author calculates good wire lengths and provides a hand chart that shows suggested lengths for different combinations of bands. Mike AB3AP's Random Wire Lengths.







One small tuner that works very well for these random length wires is the MFJ-16010. It's small so I like it for portable operation and you often see them for very reasonable prices at hamfests.








73,

Tim N9PUZ

Saturday, February 25, 2017

New Autotuner - Elecraft T-1

Well, Elecraft has been making the T-1 for some time now. I just recently added this little 20W model to my portable setup.


The MFJ-16010 I normally use for portable work is a great little tuner. However, not only is the T-1 smaller it can probably tune a lot faster than I can manually.

Elecraft claims it can even tune in both CW and SSB mode. As soon as I have the proper cables made up for the Xiegu X108G I'll have a full report.

73,

Tim N9PUZ

Sunday, February 05, 2017

Winter Field Day 2017 and Portable HF


Winter Field Day 2017
This year I and several friends from the Sangamon Valley Radio Club participated in Winter Field Day from the Clayville Historic Site west of Springfield, IL. Not only was it a chance to get outdoors with friends but it was the first field test of a new HF radio and LiFePO4 battery pack for me.

..........

I recently bought a Xiegu X108G HF rig for portable HF operating. They are readily available from several suppliers on Amazon.com. It works great as a QRP radio but also allows up to 20W of power if you desire. I love pure QRP operation with CW but with its broader bandwidth requirements 10-15W SSB seems a lot more practical. No, I'm not a purist. I just enjoy operating outdoors.

The X108G is fairly small. Here's a quick comparison to my IC-7200. Sorry for the mess. This was taken the day I unpacked the radio.


The X108G has a small but clear and bright LCD with all the pertinent information clearly shown. Along the right side where you SQL, CMP, and SWR it displays "soft" labels for the corresponding function buttons F1 - F4 to the right.


For Winter Field Day and most of my portable operating I use an end fed wire supported by a 28-foot tall fiberglass pole. For this outing I drove a piece of angle into the ground.



I use Velcro straps to secure the pole in place. There is no picture of the wire going to the top of the pole. You can't see it because it is so thin.


Here's an antenna photo before deployment. You can buy it ready made from the Emergency Amateur Radio Club of Hawaii or you can download the documentation free of charge and make your own.





Here's the rest of the "station". From left to right are 1) The X108G transceiver, a Bioenno Power 9AH LiFePO4 lightweight battery, and a manual MFJ-10610 antenna matcher.


On this particular day I chose to operate from the car because it was cold and windy. You can see from the components that it would be just as easy to toss the items in a small pack for hiking, SOTA, etc. or do "picnic table portable".

73,

Tim N9PUZ



Monday, October 05, 2015

The Art of Electronics


I read in a newsletter today that the Third Edition of the classic Art of Electronics is out. This is a "must have" reference for anyone serious about electronics in general. While it does not cover many RF topics if you had only this book and a copy of the ARRL Handbook you would have a pretty awesome reference library at your fingertips.

73,

Tim N9PUZ

Hellschreibner Digital

Last night was a first for me. Even after all these years in Amateur Radio.

Last week my Friend Mitch K9ZXO gave a presentation on the digital mode Hellschreibner at the Sangamon Valley Radio Club. I'd heard of Hellschreibner or "Hell" as it's affectionately known, but had never given it a try. Well this weekend I made sure my copy of the FLDIGI software was up to date and Sunday evening Mitch and I had a Hell QSO on 20 Meters. Woot!


Unlike other digital modes a decoded Hellschreibner signal is displayed as a picture on your screen as is shown in this Wikipedia image. This gives Hell a unique flavor that is really intriguing and takes advantage of that awesome Digital Signal Processor that sits between your ears under weak or noisy signal conditions.

73,

Tim N9PUZ

Wednesday, June 17, 2015

Thoughts on Backups

The last few weeks seem to have brought a lot of, sometimes confusing, information about backing up your computer. I don't think it should be as complicated as so many authors make it seem. Here's my take on things...

We live in a digital world. Most things that are important to our family either came to us digitally or we've scanned into digital format. Much of our lives and memories live on an inexpensive, cheaply made hard drive spinning at 7200 rpm.

Scenario #1: Computers or one of their components will periodically break. That means you need to have a second copy of anything stored there that's important to you.

Scenario #2: Crooks can break into your home or office and steal your stuff. Hurricanes, tornadoes, floods, fire, etc. are all possibilities you should consider. If you do have a copy of your important data it should be somewhere other than where your computer is located so it doesn't get stolen or destroyed by the same disaster that got the computer.

In Scenario #1 it is more likely that the disk drive will break than other failures. In this case it is nice to have an image backup so you can put in a new disk, restore the image, and be back where you left off without having to reinstall your operating system, application programs, data, etc. If it is NOT the disk drive that fails and you'll have to buy a new computer or motherboard the image won't do you much good since it's specific to the configuration of your old computer. You have a lot of reinstalling ahead of you but you should not have lost any information.

In Scenario #2 you or your insurance carrier will be buying a new computer. All of your important data was stored elsewhere so although it may be inconvenient, you haven't lost anything and you can restore it.

Please note: In any situation where you will have to reinstall application programs you need to have made copies of the originals along with the product keys, serial numbers, etc. If you copy those installation files, scanned copies of your invoice, license keys, etc. and store them in a folder on your hard drive they will be backed up along with all of your other important stuff. The one thing you do need to have separately (and off-site) is your operating system installation disks and information. This mainly applies to those of you who build your own computers. Most off the shelf computers come with the OS pre-installed if you have to buy a new one.

My recomendations?

I use an external USB hard drive and use a program such as Macrium Reflect or Acronis True Image to make a fresh image backup once a month. I also subscribe to a service called Crashplan which backs up data on an ongoing basis. It makes copies to the external USB hard disk, another computer on my home network, and off-site to Crashplan's cloud storage. You don't have to do anything specific, it just works all on it's own.

There are other products that do similar things to what Macrium and Crashplan offer. I'm sure that many are good products. These were what I used first and they have never let me down so I haven't explored others.

I know a lot of people will think this is a lot of trouble or that none of this can ever happen to them. Well, I'm sorry, you're wrong. It happens to people all over the world every single day.


Friday, February 20, 2015

What's the Difference Between Resistance and Impedance?

I was reading a Facebook discussion today and there was a lot of confusion between resistance and impedance. Someone was trying to measure a speaker with an ohmmeter and didn't understand why his "8 Ohm Speaker" measured less than 8 Ohms. One reply posted this link which I thought was pretty good...

Difference Between Resistance and Impedance

Wednesday, February 18, 2015

W9DUA D-STAR Repeater Update

A few days ago some Sangamon Valley Radio Club members and other friends from the central Illinois area got the gateway computer for W9DUA/R up and running again. The repeater is permanently linked to REF051 so it's tied together with D-STAR repeaters in Decatur and Bloomington. If you have D-STAR capability please tune up the machine nearest you and say hello to central Illinois hams!

5 Million Raspberry Pi Computers

I read earlier today that the Raspberry Pi Foundation reported than over 5 Million Raspberry Pi computers have now been sold. This number supposedly includes only true sales and does not include the number that have been given away for educational and philanthropic reasons.

Tuesday, February 17, 2015

Raspberry Pi and Arduino Tech Night

On Thursday, March 5, 2015 the Sangamon Valley Radio Club is hosting a "Show and Tell" evening that will focus on uses of the Arduino and Raspberry Pi single board computers that you've seen mentioned in Amateur Radio and Maker publications. The meeting will be held at 7:00 p.m. The location is:

American Red Cross Building
1045 Outer Park Dr.
Springfield, Illinois 62704-4408

An specific agenda is not yet finalized. There will be a presentation on considerations for applying devices such as these to an application and several SVRC members will be describing and demonstrating experiments they have been working with on their own. If anyone has an Arduino or Raspberry Pi project of your own you are welcome to bring it and share your story as well.

The SVRC will be supplying some light refreshments at the event. As such, if you are not an SVRC member, we ask that you please let us know that you will be coming just so we can get a rough head count.

There is no charge to attend.

If you plan to attend, please send an email to Roger K9LJB at:
president@svrc.org so we can plan for the refreshments.

Monday, February 02, 2015

Web Site Update

I've made a few edits to the EMCOMM Email Via Radio In Sangamon County, Illinois page on the main web site. In recent times the Byonics TT4 Tracker/KISS Mode TNC has become one of the dominant TNC types in the Amateur world. Just trying to keep people pointed in an appropriate direction.

Find out more or buy a TT4 at the Byonics web page



Friday, April 20, 2012

eBook Utilities













Do you have an iPad? Kindle? Nook? Another tablet? Besides the obvious things you can do with these handy tools they are a great place to store your own notes, documents, etc. Recently I discovered a program called Calibre which lets you convert between the various eBook formats and can also take an HTML document and create an eBook from it.

A lot of these devices can display PDF files so why bother with making an eBook? Well, the biggest reason is that an eBook can be re-sized, etc. and your documents can have all of the handy features of the other documents you download or purchase.

Check out Calibre, it's worth a look.

73,

Tim N9PUZ

Sunday, January 15, 2012

Housekeeping

I went back and corrected some typos in earlier posts and edited the first post to include links to the Yahoo Group where the amplifier is discussed and supported. Now, back to the workbench!

73,

Tim N9PUZ

Saturday, January 14, 2012

Surface Mount Components

I've made a little more progress on the amplifier. About 10 more capacitors were added before my eyes got tired. I quit before messing anything up.

I got an email asking about using "surface mount" components. There are lots of articles about this technology on the web. This one, What is SMT Surface Mount Technology from Radio-Electronics is a good beginning if you are unfamiliar with it.

The smallest SMT parts used in the WA2EUJ Amplifier are what's called an "1206" package. This designation means that the part is 0.12 inches long and 0.06 inches wide. That seems tiny but other common, but even smaller sizes are 0805, 0603, 0402, and 0201! Realistically, while using anything is possible I suppose, I think the 0805 is the smallest most hobbyists would easily deal with. The 1206 is definitely more "middle aged eye friendly."

There are techniques for hobbyists to use old electric skillets, hot plates, and toaster ovens along with something called 'solder paste' to mount SMT parts. I chose to use a traditional soldering iron and hand solder my board. I don't build a lot of projects that use SMT parts and I didn't want to gear up to do lots of SMT work for this one item.

Below is a photo of one component that's been hand soldered onto the board. It probably has a bit more solder than is necessary but frankly the soldering wasn't so ugly that I'd be embarrassed to share the photo!






















My process for hand soldering these components is as follows:
  • First I tin the pads on the PCB with a tiny amount of solder.
  • Next I use a piece of solder wick or a 'solder sucker' to remove the solder from the pads leaving a thin smooth layer.
  • Then using tweezers I set the SMT part across the pads (be sure to observe any polarity on parts like capacitors or diades that have them.)
  • While holding the part down with the tip of the tweezers touch the soldering iron to one end of the part and the solder pad at the same time to re-flow the solder.
  • Go back and add a small amount of solder to each component lead so you have a good electrical and mechanical joint.
This sounds tedious but it really goes pretty quickly once you get into it. Be careful!!! If you drop one of these parts or squeeze it too tight with the tweezers you can easily launch it across the room. 0.08" and 0.05"? It's practically a waste of time looking for it unless your shop is a whole lot cleaner and less cluttered than mine.

That's it. Easy as pie if you take your time. I recommend using one of those magnifiers with a headband while you do this work. In general you should always wear eye protection when soldering. A blob of molten solder in your eye would really take the fun out of a project.

73,

Tim N9PUZ