I made a short video where I attempt to cover antenna theory basics or as I call it "black Magic".
It's been a long time since I've blogged. The last time I really wrote down my thoughts and feelings were about my dad's death. Before that, I blogged to support my Sunday School lessons. Since then, I've blogged about projects I've built or things I've done...pictures, electronics, ham radio. Nothing really soul bearing.
I used to journal too. Maybe I can pick that up again. I didn't like my last journal: too much struggle, to much wallowing, too much self pity. I thought some terrible things, and I thought of myself terribly. The truth is, I've been hard to live with. Hard for my wife, Samantha. Hard on my kids. Hard on myself. And I've been angry. Angry, mostly at God, for allowing dad to die and the circumstances and the heartache.
I have done lots of reading. I don't know if it's been much more than usual. Perhaps more intentional. And finally, tonight, while reading "A Grief Observed" by C.S. Lewis and reflecting on recent events in my life, a new thought occurred to me.
The person I once was is dead. That person was a seed, which died in the ground. It died in order to spawn a new person. That person is me. I hardly recognize who I used to be at times. The thoughts I have thought, the things I have written, the problems I have solved, the experiences that fade in memory. The things that have remained are the promises I once made and the direction I set out.
As an aside, I am physically a different person. All of the cells in my body have died and been replaced with new cells. The atoms and chemicals have passed through. Some days I feel myself age. But further, the synapses in my brain have rewired themselves. They call it "neuroplasticity". I am in time, a different person. I think differently. I guess that's why I wanted to journal. I may never think this again.
I have always thought of time as a resource. Like money, or strength, or knowledge. Something to be managed, kept, and traded. Time is not like that at all. Time is a transformative substance that exists in the whole of this world. Part of the reality of the universe. It transforms within each moment. My house isn't the same as I was when we built it. It has been transformed over time. My wife isn't the same woman I married. I am not the same man she married. Time has transformed us. I like to think that our love is deeper than it ever has been.
I have become increasingly aware that each moment could be my last. It could be the last time I play outside with the kids. It could be the last time I lay in bed next to my wife. It could be the last time I rock my son to sleep. It could be my last chance to say, " I love you."
But this recognition hasn't been enough to me. Tonight's new idea, that at each moment I am seeding the next moment, the future me, seems to be more complete. And it gives more peace, because in that final moment on this earth, I will be born into the next. Time will no longer proceed the same way, and I will die. And in death, I will become a seed for whoever I become in the next life. I will be me, but a different me, a future me, a (dare I say) better me. But really, the only thing that separates that moment from all other moments is that I will cease to intersect with this world and with this time line. And that altogether each moment before that was building to it. Just like each moment before this one built to this moment. And every moment of me in the past adds to this me in the present. So, my aim in the present, is to make sure this moment builds the future me into who I'd like to be right now.
I finally decided to expand out of the VHF/UHF bands into HF. I wanted an "invisible" antenna, so I'm starting with an attic mounted G5RV antenna. The junior version from MFJ that covers 40 meters through 10 meters on the ham bands.
Antenna mounted as high as practical. You can see it's clear of metal objects and the ladder line goes off to the right at a 90 degree angle. Not ideal, but I'm avoiding routing it near any air ducts and wiring in the attic.
Since I have a hip roof, the radials are bent down. The supports are wire tie loops supported with nylon twine. This radial gets the closest to metal. The foil on the ducts may cause the antenna to have a null or contribute to an unwanted noise gain.
You can see the end insulator, again supported with twine. And the duct work I'm trying to avoid.
Here is the ladder line to coax transition. This was my first time installing a UHF connector on coax. It turned out neat with the blue heat shrink. Also, since this is a balanced multi-band antenna (not usually reasonant), MFJ recommended constructing a balun by looping the coax. This is 10 loops around 5" in diameter. The function of the loops is to provide high impedance to any common mode current. Ideally, in a balanced antenna, balanced feed line, all of the current would be differential mode. That is the current on the coax shield would be equal and in opposite direction from the current on the center conductor. If that's the case, the loops will not add impedance to the current and all the energy is radiated by the antenna. However, any current on the shield in addition to the differential mode current would see the inductance of the loops. That inductance helps to prevent and minimize common mode currents. You don't want common mode currents because they add to the noise of reception and can cause problems during transmission. This is because the common mode currents cause the coax to act as an antenna, and some of the energy is radiated by the coax shield instead of the antenna.
We'll see how it works when we get everything hooked up on the radio end.
Due to a corrupt file on my laptop hard drive, and HP/Compaq's lack of support for my laptop (I bought it in 2007), I decided install the Fedora 22 operating system. Fedora is a Linux distribution. I have been operating the laptop in dual boot, Windows Vista and Fedora 19 for 2 years. I found that I could address my entertainment needs (Hulu, Netflix, Nick Jr., History, YouTube, and DVD's) in Fedora. I also found I could bring 90% of my development software over using native Linux or running under Wine. I may be the only person running TinyCad / FreePCB for drawing schematics and PCB's, developing software for Windows using Code::Blocks, and developing firmware under MPLABX and Arduino on Fedora. Well, maybe not the only person, but it takes a special kind...
Also, I decided that since OneDrive is not supported on Linux, I'd drop my use of that software. I've backed up in time to the use of thumb drives and home network for moving files around. It's just as well that I'm not taking up space on a server in the cloud somewhere. Limiting demand of that sort of thing will reduce the costs of the Internet and save on fossil fuels. It's a good move for humanity, I think...
Hopefully one day I'll be back to working on things that make sense to post here.
I put my new home brew Yagi antenna up for a few minutes this past week.
Here are some pictures:
Mounted around 17 feet in the air, on the end of a painter's pole. I was hitting the repeater at Ga Tech and Bank of America building 50 miles away with this set up.
Leaned up on the car. The 2M 5 element Yagi is 66 inches long and 40 inches tall. Made out of 1/2 inch CPVC, six metal clothes hangers, and a few other parts. I'm going to add a few braces to support the pipe.
Handheld radio and SWR meter to test antenna. The antenna tested pretty good (1.2 to 1.4 SWR or 3% signal loss). You can see the input connection on the antenna as well.
There is nothing in the box, no balun, no matching network. Just one end of the driven element soldered to the center of the connector and the other end attached to the outer shield by being wrapped around a screw and compressed with a nut. The insulating material on the outside of the clothes hanger wire was scraped off at the connecting ends.
The dimensions along the boom are:
Reflector to Driven Element: 0.433 meters (17 inches)
Reflector to Director One: 0.755 meters (29 3/4 inches)
Reflector to Director Two: 1.185 meters (46 5/8 inches)
Reflector to Director Three: 1.688 meters (66 7/16 inches) of
The lengths of the elements are:
Reflector: 1.048 meters (41 1/4 inches)
Driven Element: 0.978 meters (two halves) (38 1/2 inches)
Director One: 0.940 meters (37 inches)
Director Two: 0.944 meters (37 3/16 inches)
Director Three: 0.884 meters (34 13/16 inches)
I designed the antenna with a free software package called 4NEC2. Simulated properties were 1.0 to 1.2 SWR and gain of 10 db. I didn't get that good, but not bad for a pile of clothes hangers. I definitely need to add reinforcement to keep the antenna as straight as it was on the floor when I laid it out. Still, it's fun on a stick!!! And I learned a good bit researching how to build it!
Last month, I presented on making printed circuit boards at home at the Tricounty Amateur Radio Club meeting. I featured a board I had made to interface my Baofeng UV5R HT with a computer sound card. The board features an external VOX circuit (if you turn the squelch off the Baofeng, the VOX of the radio doesn't work properly). The external VOX circuit worked great until I plugged the unit into the radio. I had two problems:
In the meantime, I did get on APRS for the first time using the little circuit, using the internal VOX of the radio. It wasn't ideal, but it worked.
I recently read "Darwin's Doubt" by Dr. Stephen Meyer. In his book he has a calculation about the probability of building a single protein necessary for life. I'd like to thank Dr. Meyer for the calculation and his wonderful book.
Dad battled cancer these past few months. On Sunday, he fought sleep until everyone he asked for came. My brothers, my sister, his sister, my mom. He had his last word with each of us. He told me he had no regrets except that he couldn't be with us longer. He was in pain and knew the end was near. He asked for hospice. They put him under and stopped the pain. He wanted to make sure my sister was cared for. A plan for her care was finalized yesterday. He wanted to make sure his granddaughter was born healthy. Olivia was born last night. She's a beautiful girl.
The news eased his breathing, even after they reduced the oxygen. We spent the night with him. We told him about the snow this morning. He had hoped for one more snow.
Slowly his breathing ceased. Then his heart stopped. All three of us sons at his side. I know my dad passed into the glory of our Lord. United again with his maker, and his passed loved ones. No more cancer. No more pain. My daddy and my hero died bravely on his own terms. We will always love and remember him. Thank you for your thoughts, prayers, and support.
This past weekend, my dad, brothers, and I were able to go to the Grand Canyon. The Grand Canyon was on my dad's "bucket list". I was so glad we could all go. Here are some of my favorite pictures from the trip.
It's hard to capture the scale of the grand canyon. Standing on one side, the other side is roughly 20 miles away and the length of it is hundreds of miles. This picture captures layers of ridges and holes, and with some rock in the foreground to the rock at the horizon, this is the best picture I had that captures scale.
Today has been a long day. Tomorrow we arrive at the Grand Canyon. One of the things dad's always wanted to do. I'm afraid of the "what then?" The "what next?" I know fulfillment in life isn't doing a certain thing or going to a certain place. It's in knowing a certain One and knowing each other. I guess that's what tomorrow should be about. And the "what then" is to keep building our relationship and to keep fighting. And mostly, no matter the future, to draw near to the God who made us and who makes us whole.
Husband. Father. Follower of Christ. Electrical Engineer. Electronics and woodworking hobbyist.