My 1st circuit design and implementation :)

I've decided to build a GPS receiver for my ICOM IC-9100.  No particular reason other than I was looking for an electronics project and this one seemed to have enough complexity (which would be VERY little to others, but a LOT for me!) to make it interesting and fun.

I created an account on Circuit Lab and designed my 1st circuit.  Actually, I really designed it on a sheet of paper and after editing, and editing, and editing...  I decided to look for an online way of designing a circuit - I Googled circuit design and Circuit Lab popped up - I created an account and started.  It seems pretty simple, which is exactly what I'm looking for right now.

Here is the schematic of my 1st design:

I needed a circuit that would take a 12 - 14vDC source and transform it to 5vDC.  I'm planning on using a Garmin 18x LVC, which needs about 100mA @ 5vDC.  Since I had most of the components already figured out, I thought that I'd add an LED - you know, just for fun!  So, I did :)

Here's my breadboard pic:

As you can see, the LED is lit and the voltages are all pretty much right where they are supposed to be!  I'm pretty excited - this is the first time that I actually designed a circuit with a voltage regulator, couple of capacitors, and an LED.  AND it WORKS!!!  Woo Hoo!!!

73 de KJ4WLH

A Very Begali Christmas

Merry Christmas 2012!

The Bates family had a great 2012 Christmas; it was really nice to have the whole family sitting around the Christmas tree, laughing, smiling, and opening gifts.

The Ham Radio gifts this year were very nice:  2 Begali's - A Sculpture and a Blade.  One for each type of CW - they are just beautiful, they look so much better than I can use them.  I can only hope that one day I'll be worthy of them.

73 de KJ4WLH

Boy Scout - Field Day with Skeet & Radio Fun

I'm back home after a wet, wet weekend.  The weather guys all week long said, "Beautiful weather - upper 50's during the day and possible rain late Sunday afternoon."

Well, they were partially right - Saturday afternoon the temp did warm up to the upper 50's.  However, around 1am on Sunday morning, the downpour that arrived was not very nice :(  Eventually, the tent decided to perform the same function as a river and little rivers flowed through.  There is just nothing like a wet sleeping back to ruin an otherwise pleasant sleep!

Anyway, Saturday was a really nice day - the Scouts had a great time shooting skeet; this year we only shot around 4,000 shells - down from 5,000 last year.  My youngest son ended up shooting 250 shells, has a HUGE bruise on his right shoulder and completed the Shooting Merit Badge requirements by hitting 39/50 skeet!  He (and I) was very excited.

I set up a radio station on Saturday morning and really had a great day!  I took my Icom IC-7000 and Buddipole with me.  The first thing I wanted to do was check in to the Central Virginia 6m Net (50.215) that run every day at 7am and 8am.  The Buddipole aluminum tubing was pretty chilly in the AM as the temp was around 35 degrees or so.  I managed to get the Buddipole set up with a 6m dipole configuration and I heard Ralph (WA4FEG) calling for check-in's to the net!  I was very excited!

(A note on the Buddipole configuration - if you decide to pick on up - you MUST own a antenna analyzer of some sort.  It's just not an option to try with your radio - there is so much variation in locations, coil tap locations, and antenna whip length that you start each band "excercise" in the "general ballpark" and spend a bit of time trying to find a good resonant config.  Takes some time, but I can't imagine how'd I accomplish it with a analyzer!)

Rig Setup at Scout Camp

I used the battery power from the car as the power source.  I had forgotten that I need to run the car when using the IC-7000 on full power - but remembered VERY quickly when I keyed up to check-in to the 6m net.  My IC-7000 immediately power cycled, I jumped out of the chair and started the car, and then tried to check in again - this time success!!!

Buddipole - Set up for 6m configuration

Field Day Setup

My youngest son came on over to visit later in the morning.

My Assistant - Will

 I made a few contacts during the day with folks around the US, Portugal, and heard quite a few from Europe, Canada, Australia, and Mexico - quite a variety.  I had about 8 - 10 scouts talk to other hams during the day; it was pretty fun for everybody involved!  When the day had about ended, I had the opportunity to share a bit of detail with 3 boys who seemed quite interested in obtaining their Tech license - I'll have to follow up with them later on and see if the interest remains.

So, other than some crappy, late Sat night rain, and a cold - it was a great field day!

73 de KJ4WLH (reporting from a nice, dry QTH!)

6m Dipole is complete - I'm finally back in business.

I took some time, but I finally made my 6m dipole.  Since I work for a plumbing company, I decided to use copper pipe and fittings :)  Here are some pics:

I did a bit of antenna modeling before I made this antenna.  I was hoping that it would be as good as the model suggested - the 1/2" copper pipe really gave it a nice bandwidth!

Since I was trying to get it resonant for weak signal work, you can see that it's really matched quite well for 50.125 - I'm quite happy!!!

73 de KJ4WLH

ICOM IC-7000 Low Power Output RESOLVED!

I've recently been using my Icom IC-7000 inside my house as a convenient way to listen to W1AW Morse Code practice sessions.  One afternoon, I was on 40 meters and decided to have a QSO with a fellow ham. I went to key and noticed that my power output level was peaking around 60 watts +/- or so.  Since I had the power output set at 100% (or 100 watts), I was concerned.  I knew that my antenna was good, the auto tuner had been successfully initiated and was operational.

Hmm, had I managed to break something?  Time to search the Internet for help!

It would seem that I'm not the only person who has had this issue.  The first answer was very common, something along the lines of:  "The IC-7000 needs 13.8 volts; anything less will affect power output."  I was already familiar with that problem - mostly due to my operation in my vehicle.  The IC-7000 worked great when the car was running, but when the car was stopped (engine not running), power output > 50 watts caused the unit to cycle off and back on.  Apparently, the solution for that problem is a "voltage booster."

On to the next "most likely" cause - bad fuses.  Really?  Bad fuses; corrosion?  Well, guess what - yep, that was actually the problem.  I found a good article by AB4OJ - Link Here -> Check out the heading "Low Power Output on Transmit."

I checked the 30 Amp ATC fuses and take a look:

IC-7000 30 Amp ATC Fuses

Notice the nice dark corrosion line across them?  Yeah, I noticed them also.  I took a pocket knife and scratched some of the oxidation off the fuses, put the back in the fuse holders and yep, the IC-7000 went back to transmitting all of 100 watts.

Next step:  get out my dremel and buff the oxidation off the fuses.

73 de KJ4WLH

1st CW QSO! Thank you KD2OY!

After many months, even years, I finally got up the courage to give a CQ using Morse Code.  Much to my terror, David Nadel - KD2OY, returned my call and we had a short QSO.  It was short, mostly because I was so nervous that I didn't know what to say!

I would really like to thank a couple of guys who have provided a LOT of encouragement and support:  Dave Meier (N4MW) and Armand Hamel (WA1UQO).  I would have abandoned CW long ago if it weren't for these 2 guys!

The 1st contact has been logged - onward and onward!!!

73 de KJ4WLH

Antenna Modeling – The Practical Use

What do these software products all have in common:  EZNec, cocoaNEC, NEC 2, and NEC-Win?

1. They are intimidating, obscure, and un-intelligible software programs somehow related to Amateur Radio.
2. They each provide a means to use mathematical sets of formulas to simulate antennas in the "real world."
3. Electrical Engineers, PhD's, Nerds, and the socially unacceptable are the only humans who know the "secret and arcane" art of antenna modeling using these software tools.
4. These are very expensive software products, well out of the reach of a typical Ham.

No, the answer is not "3"; the correct answer is "2"!  Yes, really - I'm not kidding…

One of my favorite things to do in Amateur Radio is trying to model the "perfect" antenna.  I've "invested" (or wasted depending upon whom you ask!) a lot of time with EZNec (on Windows) and cocoaNEC (on Mac) and I really enjoy them a lot.  I've often asked myself questions like:

• I wonder what that dipole would look like in my back yard?
• What does a 3 element, 2-meter yagi do at 8' above the ground?
• How does a j-pole really radiate?
• Can I make my own Buckmaster (and save a TON of $$)?

Recently, I was able to put my "investment" (of time) to good use.  I'd decided that I wanted to put up a 40m dipole and remove the doublet that was in its place.  Sure the doublet worked OK, but I'd recently discovered just how inefficient that antenna radiates on it non-harmonic frequencies.  It doesn't really matter what "it" is, but I like things that work efficiently and my doublet surely didn't.

I had to opportunity to "design" my own dipole.  How tricky can that be you ask?  As tricky as you want to make it.  Since I knew how to use EZNec and cocoaNEC, I didn't just want a flattop dipole with it's 70+ Ohm feedpoint and 1.8+ SWR across the frequency band for 40m (see Figure 1).  I used cocoaNEC to model a dipole, sized for 40m, about 45’ above the ground – which was very close to my QTH’s backyard setup – to see what a regular dipole would look like.

Figure 1 - 40m Dipole "Flat Top"

Since the 40m antenna is lower to the ground than the optimal height, I started changing my model by changing the legs of the dipole.  I started off by slightly raising the legs by 10 degrees at the insulator and saw the feedpoint resistance drop a little.  Eventually, I managed to find a nice combination of dipole leg “angle”, based upon the height over ground.  I was also able to adjust the length of the legs to get the lowest SWR across the lower part of the 40m band.  The SWR model is show in Figure 2.

Figure 2 - 40m "V" Dipole

During November of 2012, I managed to find some time to hang my 40m dipole based upon the calculations.  I hung the wires and balun, trimmed, re-hung, trimmed, re-hung, etc. for a few hours.  When I was finished, I used my analyzer to see just how close I was.  Figure 3 shows the graph based upon the numbers my analyzer showed.  The curve is about as close to a match (compare Figure 3 to Figure 2) as I could ever expect!  I was so pleased – it has been a while since a project that I’m working on has turned out so well!

Figure 3 - Actual Analyzer Measurements at my QTH

As I’m writing this, I still can’t believe just how accurate the EZNec and cocoaNEC programs are.  I know it’s not rocket science, but I was able to design an antenna based on my requirements, build the antenna, and finally, measure to see that it matches the antenna design.

Once all the measurements were complete, I got right on the air.  The ARRL was having a Sweepstakes competition and the contacts were rolling in!  Perhaps band conditions were great or my antenna worked even better than I’d dreamed ☺  Either way, there were many contacts to be made!  It was a great way to end a weekend!

If you think that you’d be interested in trying to model your own antenna, RARC will be offering a 3 or 4 week “Introduction to EZNec Antenna Modeling” class in the late winter/early spring.

73 de KJ4WLH