Sunday, October 27, 2013

Heat Death Vs Eternal Life

People have an enormous capacity for missing the obvious. Common sense, as it turns out, isn't, and the consequence is that people will waste their entire lives chasing after something as fleeting as beauty, or "a good time". When it comes to missing the obvious few people miss the obvious as those who profess a disbelief in the presence and person of God. The Bible says it best:

1 The fool says in his heart, “There is no God.”
They are corrupt, they do abominable deeds,
there is none who does good.
2 The Lord looks down from heaven on the children of man,
to see if there are any who understand,[a]
who seek after God.
3 They have all turned aside; together they have become corrupt;
there is none who does good,
not even one.

When God looks out over us, He finds people oblivious to what they are doing. Every day we live our lives as if things are the same as they ever was. Even crazier, we say that when we are in the process of completing something we are 'making progress.' In reality we are kind of clueless about how the universe works. Things are not going to continue forever. Even the most ardent atheist believes that the universe will come to an end. While they do not believe that God has redeemed us by His son Jesus, and made us joint heirs in His kingdom, they do believe that everything stops. Literally, everything stops. The universe ends, many of them contend, when the energy level of the universe is of a uniform density, thus producing a maximum state of entropy. This even is known as "Heat Death".
Don't worry, heat death is a long way away, except between 2 and 3 pm when all I want to do is take a nap. I'm fairly certain that's the closest I'll ever be to heat death. There's plenty of energy available in the cosmos to keep us going for quite a while. One thing this does do, however, is illustrate one of the chief differences between people who believe Jesus Christ is the Son of God, and people who do not believe God's truth. Every morning when an atheist gets up, if he is honest, he  has to confront the fact that everything he will do on that day is meaningless. Most of them choose to pretend that what they do matters, they don't want to think about the implications of meaninglessness in their lives. They can't escape the truth though, if they are correct, there is no progress, heat death takes all that away. As Christians we have knowledge of the future through God's word:
Revelation 22:1-5
 1 Then the angel showed me the river of the water of life, bright as crystal, flowing from the throne of God and of the Lamb  2 through the middle of the street of the city; also, on either side of the river, the tree of life with its twelve kinds of fruit, yielding its fruit each month. The leaves of the tree were for the healing of the nations.  3 No longer will there be anything accursed, but the throne of God and of the Lamb will be in it, and his servants will worship him.  4 They will see his face, and his name will be on their foreheads.  5 And night will be no more. They will need no light of lamp or sun, for the Lord God will be their light, and they will reign forever and ever.
God makes this possible through the blood of His son. When we gather for the Lord's Supper, we don't have the face of the Lord before us, we have  reminder in a meal that the sacrifice has been made and the road to the kingdom is secured. Let us partake today knowing that we look forward to Eternal Life, and not Heat Death.

Tuesday, October 15, 2013

Sometimes it Pays to Check the Power Output!

The QRPARCI Fall QSO Party took place second weekend in October. I took an oppurtunity to participate in it albeit in a limited fashion. Mainly I wanted to test deploy my End Fed Half Wave antenna, and have some fun slingin' some dits and dahs.
20m Portable Operation, QRPARCI Fall QSO Party
 
Saturdays I work a monster 12 hour shift beginning at noon. After I got done doing some UI testing, and before the next batch of jobs I have to monitor began, I decided to take a half hour lunch break to feed my brain using ham radio, specifically the QSO Party. I sprinted out to "El Toro" (our red Mazda Tribute) after clocking out for lunch, and got to my station. This is the third time I've deployed in the parking lot using a wire antenna like this, and it was the first time I've used the EFHW to make a QSO from the parking lot. I made exactly one QSO, with NM4T on 20m. The EFHW did well over all, lots of signals, some were VERY loud, especially the SKCC WES stations near the QRP watering hole. I did make a couple of mistakes though.
 
1. I assumed I had everything I needed in my box. when I got out there, I realized I didn't have the connector for my 7AH gel cell battery. I did have the end that plugged into the radio, but not the end that plugged into the battery.
 
2. I could have used a second roll of fishing line. The EFHW works well on 20m with 33' or 66' of line deployed. I used 33' because I didn't have a way of stretching the second 33' section out, and time was too short to attempt a redeploy of the antenna. I didn't want to cut the line because I felt that would have been a waste of string.
 
3. I intentionally left my NoGAwatt at home, and I missed it. I like having the reassurance that my forward power is good to go. I would have checked, and then removed it from the line. I've discovered that it does add some non-trivial at QRP levels loss in the line, so I left it home.
 
Sunday I try to limit my "on the air" time in favor for some "play with the kids time" but I did take a little time to play radio at my in-laws from their driveway. We went over there to eat hamburgers, and the kids were playing as the sun was setting. This time I deployed on 40m, and confirmed my issue number 2: when setting up an EFHW on 40m as an inverted vee (It kinda looks more like a caret (^)to me) It helps to have two separate lines, one to support the middle, and one to support the far end. I keep a piece of paracord handy in the box to tie down the end where the RF goes.
 
Best Pic I have of my Sunday Night Setup
This time instead of using 20m I decided to go with 40, using "The Killer Watt Radio." It's supposed to be calibrated to transmit at one watt with the little 8 cell AA battery pack I use. That's with a fresh battery pack. I did take a better picture of my setup, but right when I snapped the pictured, my phone's battery died and it was lost :(. I did managed to get two QSO's on 40 before the skeeters got bad, and about carried me off. The first QSO was with WB4MNK, he was so loud, I had to turn the gain down to be able to hear anyone but him when tuning to people calling on nearby frequencies.
The second QSO was with N0WL. I had hoped that I could stay around and work him during the 4SQRP SS after the ARCI Party, but I could not stand the skeeters.

Monday morning I decided to check out my power levels and I discovered something interesting. The open circuit voltage on the battery pack was down to about 11.7 volts, and I was transmitting about .689 watts on both radios! This makes my Fall QSO party power multiplier a 10. Heh! that's one way to boost your score.


Here's what I learned:
66' of wire can be tough to quickly deploy without two support lines. I could have gone for a single support on the far end as High as I can get it, but I think I get some benefit from having the high current portion of the antenna (on 40m at least) at the apex. Might be worth modeling, if I can ever get a computer that will successfully run software.
  • Check and double check your kit, and make sure you have power redundancy. That saved my bacon both days, because I forgot the part that hooks up to my battery the first night, and then I forgot the part that hooks up to the radio the second night!
  • If you think you'll use it, bring it. I didn't technically "Need" my NoGAWatt, but I missed having it.
  • Bugspray is your friend, but having a layered strategy is better. Wish I had long sleeves, bugspray, and some sort of "area skeeter control" gadget with me instead of just bugspray. Them things are meaner now than when I was a kid!

73,
GB Hoyt
KG4GVL

Monday, October 14, 2013

First, You Gotta Build the Stuff to Use to Test the Stuff You Build

I'm in the process of designing and building my own MOPA using a 10DE7 vacuum tube. I want to use one tube for both the Master Oscillator and Power Amplifier. It's been a great learning experience so far, I go to sleep every night with Colpitts Oscillators dancing in my head. One of the tools I've used when building a radio has been a Peak to peak RF voltage reader. This circuit is described in Dave Benson's instructions for his SW+ series of radios. Better go download the manuals! Dave's closing shop in favor of retirement, and he won't leave the site up forever. When I built the circuit, I decided to put it on a board, and let it dangle off of my dummy load. That got annoying though, and there was always the problem of what to do with the dummy load when I was done measuring power. Evenually I just ripped the circuitboard off of the dummy load. Then I had a thought.

Since the circuit uses components that are QRP level, I decided to go with a QRPish dummyload. A long time ago I located some 2 watt 200 Ohm resistors. I used them to make a dummy load that would handle 8 watts. The circuit board once upon a time dangled from the dummyload like some sort of absurd dangily earring. It just makes more sense to put the dummy load on the circuitboard. This is the result shortly before hookup:

Dummyload Added!
To insure that all my resistances were correct, and I could sanely measure voltages, I did a quickhookup to check out voltages, etc, before putting in an Altoids tin.

Ready To Test!
 Once the little job was ready to permanently affix to the inside of an altoids tin, I located some two sided sticky stuff I had laying around, and attacted to the bottom of the altoids tin. I may have said "Oh Good Grief" or something like that when I realized that the board was a lil' bit crooked in relation to the bottom of the box. After hooking up a BNC connector, and attaching the wire to my test point, my RF voltage meter was ready to use.

Ready to Use!

I plan on using this to test my designed Colpitts oscillator, but until then, the glowbug I have now will have to do. The first time I measured the voltage things seemed a little low.


This seems low.

That measures out to 0.9216 watts. ((Vp-p * sqrt(2)/4)^2 / 50) And then I got to thinking. I remembered that the last time I checked the RF output on this lil' tube radio was without my NoGAwatt attached! I pretty much just used just the dummy load dangling off the back of the radio. That was one of the reasons why I moved my dummyload onto the circuit board.
I took the NoGAWatt out of the equation and this is what I got:
Much Better Now!
For a whopping total of 1.092 watts! Just to make sure there wasn't anything crazy happening with thee coax I was using, I used both pieces of coax I used for the first test, and substituted a BNC female to female barrel coupler to see if adding that particular section of coax would alter the power out at all:


Not Much!
 That confirmed my suspicion, The NoGAwatt was consuming power. Not surprising, since something has to make the needle move to indicate forward and reflected power. I bet I could calculate the maximum amount of power lost to the meter based on the full deflection reading of the needle...
ah, maybe later. Right now is time for operating!


One last internal shot.
 I still have some prettying up to do on this lil-bit-o-kit, namely, I need to find some better way of hooking the RF measurement points up to make them accessable without being in the way, or easy to short out. Right now I'm just using the "situational awareness" method, and that doesn't always pan out.
Eventually, I hope to make this something that is publish worthy. We'll see how that works out.
73,
GB Hoyt
KG4GVL



Wednesday, October 9, 2013

Life!

A brief overview of what's happening in my world:

My girls are growing up. Nothing makes me happier than to see them meet new challenges, like with my middle child learned to right her bike "in about ten seconds!" on her sixth birthday. So far, my strongest test as a father has been listening to her say "I don't need any help anymore!" because that's the point. The oldest is in the third grade, and she picked up Andrew Peterson's book On the Edge of the Dark Sea of Darkness at my suggestion. She wanted to know what grade level it was, and if there would be an AR test. Assigning books a 'grade level' and giving them 'AR tests' has got to be a scam, because the readers have now gamed into what is and isn't ok to read as a result. Oh, and you are only allowed to check out certain books at the library based on your reading level. At least that's what my daughter thinks. Checking out books based on a "grade level of reading" seems like a bad idea. My favorite book in the 3rd grade was an historical account of the discovery of various elements by scientists in the 17th-early 20th centuries by Isaac Asimov called The Search for the Elements. I liked it because it was science and history, and it belonged to my dad, and he said I should read it. I never took an AR test about it, and I mispronounced a lot of words along the way, but I learned and I liked it. Don't people like to read anymore? Don't people read things too hard for them to read because they want to be better at it, and they find the subject matter interesting?

Sorry for sounding like an old fogey.

News from the Station of KG4GVL, I discovered another blog, and put it under my blog list: RaDAR-America. It espouses an interesting concept, rapidly deployable ham radio operations. Here's a quote of this short blog post that concisely states the theory of the group:

...the difference between RaDAR and SOTA.

The summit is the operations destination of the SOTA operator. The journey to the summit (including, and back) is the operations focus of the RaDAR operator. For every five QSO's, the RaDAR operator is required to move (on the move QSO's are allowed as long as the five QSO rule is valid).
Seeing as how the highest point in FL doesn't qualify for SOTA, I think this could be a wonderful excuse to get outside and do ham radio!

On the workbench, I'm working on a MOPA using a singe tube.
more on that later.

Soon I will be 36, more on that later as well.