I have had what I would consider an interesting life. Born into a Navy family full of travellers, I've had many opportunities to meet different people, experience different parts of the country and see different parts of the world. One of my biggest desires in life is to share the connections I see between seemingly disconnected pieces of the puzzle known as "Earth" and "Life". I believe in a God who has done, will do, and is doing strange things in an effort to help us see these connections too. We all play a small part in something I've known as "Telos" or "The End" end meaning not a stopping point, but a purpose. For a while I've seen myself in a role that has made me the proclaimer of "The Telos", a herald of the way, something most people refer to as 'preacher' or 'evangelist'. I've spent hours preparing material that basically says the same thing over and over again:
0. The Universe is apart from God, contrary to His Telos because humanity has made a Telos for itself despite the fact our knowledge of the implication of our self made Telos is limited, incomplete, and contrary to what has already been proclaimed.
1. God Himself has made a Way of reconciliation and restoration to Him.
2. Without that Way, you will not see His Telos in this 'Earth'
3. This Way is through and along side of His Son Jesus, whom He sent as Himself in the flesh
4. Your role in "The Telos" can only be realized as you walk the Way God has/will/is providing.
As I see it, ever sermon you hear will be about one of those five points.
I could be wrong, but that's what I see. Usually, when I preach, I try to combine points 1, 2, 3. I want to leave you walking along the Way. Point 4 takes the longest to workout, and accept because you will constantly be realizing your role in the Telos until the Telos is realized. Point 0 is obvious when observing the 'evil in the world', and overarches, influences, sometimes contradicts, sometimes reinforces each of the other points.
I want to help you understand that God's purpose for you is for Him and you to mold your self-made Telos into His Telos, to follow that Telos to it's finality, and to rejoice in the acceptance of its rewards.
EDIT: I've seen Telos spelled Telos, Telios, and Teleos. I don't understand there to be any differences between them all, just understand I am refering to The End of the Process in it's most generic consideration.
Monday, August 29, 2011
Friday, August 26, 2011
Amateur Radio and Irene
Irene is a big wet cold monster bearing down on the Carolinas, right now the storm is still on the way, and almost upon them.
If you are a shortwave listener and your radio can do upper or lower sideband, you should checkout the following frequencies:
If you are a shortwave listener and your radio can do upper or lower sideband, you should checkout the following frequencies:
Hurricane Frequency Listings (Unless otherwise noted, times are UTC, freq in kHz) Government, NGO & Military frequencies 02670.0 USB USCG wx Cape Hatteras NC (0133 1303) 02670.0 USB USCG wx Fort Macon NC (0103 1233) 02670.0 USB USCG wx Eastern Shore VA (0233 1403) 02670.0 USB USCG wx Hampton Roads VA (0203 1333) 02670.0 USB USCG wx San Francisco (0203 1403) 02670.0 USB USCG wx Los Angeles/Long Beach CA (1303 2103) 02670.0 USB USCG wx Honolulu (0903 2103) 02670.0 USB USCG wx Marianas Section Guam (0705 2205) 02802.4 USB American Red Cross Disaster (F-91) 03171.4 USB American Red Cross Disaster (F-92) 04426.0 USB USCG wx NMN Portsmouth (0330 0500 0930) 04426.0 USB USCG wx NMC San Francisco (0430 1030) 04724.0 USB GHFS 05136.4 USB American Red Cross Disaster (F-93) 05141.4 USB American Red Cross Disaster (F-94) 05211.0 USB FEMA 05236.0 USB SHARES Coordination Network (nationwide HF voice coordination) 06501.0 USB USCG wx NMN Portsmouth (0330 0500 0930 1130 1600 2200 2330) 06501.0 USB USCG wx NMO Honolulu (0600 1200) 06501.0 USB USCG wx Marianas Section Guam (0930 1530) 06712.0 USB USAF GHFS SAR 06739.0 USB GHFS 06859.5 USB American Red Cross Disaster (F-95) 07507.0 USB USN/USCG hurricane net (pri) 07508.5 USB FAA Caribbean hurricane net 07550.5 USB American Red Cross Disaster (F-96 - primary) 07698.5 USB American Red Cross Disaster (F-97) 08764.0 USB USCG wx NMN Portsmouth (0330 0500 0930 1130 1600 1730 2200 2330) 08764.0 USB USCG wx NMC San Francisco (0430 1030 1630 2230) 08764.0 USB USCG wx NMO Honolulu (0000 0600 1200 1800) 08992.0 USB GHFS 09380.0 USB USN/USCG hurricane net (sec) 10493.0 USB FEMA 11175.0 USB GHFS 13089.0 USB USCG wx NMN Portsmouth (1130 1600 1730 2200 2330) 13089.0 USB USCG wx NMC San Francisco (0430 1030 1630 2230) 13089.0 USB USCG wx NMO Honolulu (0000 1800) 13089.0 USB USCG wx Marianas Section Guam (0300 2130) 13200.0 USB GHFS 13510.0 USB Pictures from CFH Halifax (1000-2200) 14396.5 USB SHARES Coordination Network (nationwide HF voice coordination) 15016.0 USB GHFS 17314.0 USB USCG wx from NMN Portsmouth (1730) 17314.0 USB USCG wx from NMC San Francisco (1630 2230) Amateur Radio HF Emergency Hurricane Nets 01984.0 LSB Virgin Islands (VI, Puerto Rico, Lesser Antilles) 03710.0 LSB Puerto Rico 03808.0 LSB Caribbean Wx (1030) 03815.0 LSB Antigua/Antilles Emergency and Weather 03815.0 LSB Inter-island (continuous watch) 03818.0 LSB Antigua/Antilles 03845.0 LSB Gulf Coast West Hurricane 03862.5 LSB Mississippi Section Traffic 03865.0 LSB West Virginia Emergency 03873.0 LSB Central Gulf Coast Hurricane 03873.0 LSB Louisiana ARES Emergency (night) 03873.0 LSB Texas ARES Emergency (night) 03873.0 LSB Mississippi ARES Emergency 03905.0 LSB Pacific ARES (Hawaii) 03905.0 LSB Delaware Emergency 03907.0 LSB Carolina Coast Emergency 03910.0 LSB Mississippi ARES 03910.0 LSB Louisiana Traffic 03910.0 LSB Virginia Emergency, Alpha (ARES/RACES) 03913.0 LSB New York State Emergency 03915.0 LSB South Carolina SSB NTS 03915.0 LSB Massachusetts/Rhode Island Emergency 03917.0 LSB Eastern Pennsylvania Emergency 03920.0 LSB Maryland Emergency 03923.0 LSB Mississippi ARES 03923.0 LSB North Carolina ARES Emergency (Tar Heel) 03925.0 LSB Central Gulf Coast Hurricane 03925.0 LSB New York State Emergency 03925.0 LSB Louisiana Emergency (altn) 03927.0 LSB North Carolina ARES (health & welfare) 03925.0 LSB Southwest Traffic (altn) 03935.0 LSB Belize 03935.0 LSB Central Gulf Coast Hurricane 03935.0 LSB Louisiana ARES (health & welfare) 03935.0 LSB Texas ARES (health & welfare) 03935.0 LSB Mississippi ARES (health & welfare) 03935.0 LSB Alabama Emergency 03937.0 LSB Western Massachusetts ARES 03940.0 LSB Southern Florida Emergency 03947.0 LSB Virginia Emergency, Bravo (health & welfare) 03950.0 LSB Hurricane Watch (Amateur-to-National Hurricane Center) (altn) 03950.0 LSB Northern Florida Emergency 03955.0 LSB South Texas Emergency 03960.0 LSB Northeast Coast Hurricane 03965.0 LSB Alabama Emergency (altn) 03965.0 LSB Connecticut Emergency 03967.0 LSB Gulf Coast (outgoing traffic) 03970.0 LSB New Jersey ARES 03975.0 LSB Georgia ARES 03975.0 LSB Texas RACES 03980.0 LSB Southeast Virginia ARES 03987.5 LSB Mexican National 03990.5 LSB New Jersey RACES 03993.0 LSB New York State RACES 03993.5 LSB Gulf Coast (health & welfare) 03993.5 LSB South Carolina ARES/RACES Emergency 03995.0 LSB Gulf Coast Wx 03995.0 LSB Western New York State Coordination 07055.0 LSB El Grupo Seguimiento de Huracanes (Spanish) 07060.0 LSB Mexican (emergency and health & welfare) (Spanish) 07070.0 LSB Manana (Baja California) 07090.0 LSB Central America Emergency 07145.0 LSB Bermuda 07165.0 LSB Antigua/Antilles Emergency and Weather 07165.0 LSB Inter-island 40-meter (continuous watch) 07225.0 LSB Central Gulf Coast Hurricane 07230.0 LSB New York State Emergency 07230.0 LSB Southwest Traffic 07232.0 LSB North Carolina ARES Emergency (Tar Heel) (altn) 07235.0 LSB Louisiana Emergency 07235.0 LSB Baja California 07235.0 LSB Central Gulf Coast Hurricane 07235.0 LSB West Virginia 07235.0 LSB Louisiana Emergency 07240.0 LSB American Red Cross US Gulf Coast Disaster 07240.0 LSB Texas Emergency 07240.0 LSB Virginia Emergency, Bravo (health & welfare) (altn) 07242.0 LSB Southern Florida ARES Emergency (altn) 07243.0 LSB Alabama Emergency 07243.0 LSB South Carolina Emergency 07245.0 LSB Southern Louisiana 07245.0 LSB New York State RACES 07247.5 LSB Northern Florida ARES Emergency (altn) 07248.0 LSB Texas RACES 07250.0 LSB Belize 07250.0 LSB Texas Emergency 07254.0 LSB Northern Florida Emergency 07260.0 LSB Gulf Coast West Hurricane 07260.0 LSB Virginia Emergency, Alpha (ARES/RACES) (altn) 07264.0 LSB Gulf Coast (health & welfare) 07265.0 LSB Salvation Army Team Emergency Radio (SATERN) 07268.0 LSB Bermuda 07268.0 LSB Waterway 07273.0 LSB Texas ARES (altn) 07275.0 LSB Georgia ARES 07280.0 LSB NTS Region 5 07280.0 LSB Louisiana Emergency (altn) 07283.0 LSB Gulf Coast (outgoing only) 07285.0 LSB Louisiana ARES Emergency (day) 07285.0 LSB Mississippi ARES Emergency 07285.0 LSB Texas ARES Emergency (day) 07290.0 LSB Central Gulf Coast Hurricane 07290.0 LSB Gulf Coast Wx 07290.0 LSB Texas ARES (health & welfare) 07290.0 LSB Louisiana ARES (health & welfare) (day) 07290.0 LSB Texas ARES (health & welfare) 07290.0 LSB Mississippi ARES (health & welfare) 07290.0 LSB Hawaii Emergency 07290.0 LSB Traffic 14185.0 USB Caribbean Emergency 14200.0 USB (Please advise) 14215.0 USB Pacific Inter-island 14222.0 USB Health & Welfare 14245.0 USB Health & Welfare 14265.0 USB Salvation Army Team Emergency Radio (SATERN) 14268.0 USB Amateur Radio Readiness Group 14275.0 USB Bermuda 14275.0 USB International Amateur Radio 14283.0 USB Caribus (health & welfare) 14300.0 USB Intercontinental Traffic 14300.0 USB Maritime Mobile Service 14303.0 USB International Assistance & Traffic 14313.0 USB Intercontinental Traffic (altn) 14313.0 USB Maritime Mobile Service (altn) 14316.0 USB Health & Welfare 14320.0 USB Health & Welfare 14325.0 USB Hurricane Watch (Amateur-to-National Hurricane Center) 14340.0 USB Louisiana (1900) 14340.0 USB Manana (1900) 14340.0 USB California-Hawaii 21310.0 USB Health & Welfare (Spanish) 21390.0 USB Inter-Americas (health & welfare) 21400.0 USB Transatlantic Maritime 28410.0 USB New Jersey ARES 28450.0 USB Health & Welfare (Spanish) Hurricane Watch Net Whenever a hurricane is within 300 miles of land in the Northern Western Hemisphere, the Hurricane Watch Net is operational on 14325 kHz. The Hurricane Watch Net provides communication between the amateur radio station W4EHW located at the National Hurricane Center, and the affected areas. American Radio Relay League (ARRL) During a communications emergency, W1AW transmits special bulletins hourly by voice, teleprinter and CW (Morse) according to the following schedule: Please note that these frequencies are in Mhz Voice (hh:00) 01855.0 03990.0 07290.0 14290.0 18160.0 21390.0 28590.0 Teleprinter (hh:15) 03625.0 07095.0 14095.0 18102.5 21095.0 28095.0 CW (hh:30) 01818.0 03581.5 07047.5 14047.5 18097.5 21067.5 28067.5
Check out the action live on the air people!
Remember to keep the QRM (Man made interference) down!
Monday, August 22, 2011
"Death to the Resistors!" update A
So here's the story so far,
I've got five resistors, nominally valued at 100 ohms. I'm going to execute a plan to test their power rating. I've learned a lot about testing standards, and resistor power ratings, probably more than I wanted to know. Apparently there are some rigid standards, and exacting practices people go through to test and certify parts for particular applications. Some of these tests are daunting to say the least!
Test a resistor for 10000 hours?
Meh, not going to happen for me.
That's just one of the current requirements a manufacturer has to meet for the current round of MIL-SPEC testing.
I'm not going to MIL-SPEC certify these resistors. I am however, going to take some suggestions offered to me from the good folks on QRP-L.
From Mike WA8BXN:
I'll devise a series of tests, first thing I have to do though is rig up a test jig to measure the actual value of the resistors! My first attempt was a bust due to 9v battery issues on my digital VOM. Once I took care of that, I realized it can be pretty tricky to measure the values of the resistors. They have this thing about holding still. I don't think they like going into the holes that I stuff them in. I'm pretty sure the hot tin/silver amalgam I apply to them upsets them too.
I've only ever had one capacitor blow up on me though... long story, but I now never apply power to a rig with the top off without first putting on my safety glasses, and yes, I had safety glasses on that time!
I've got five resistors, nominally valued at 100 ohms. I'm going to execute a plan to test their power rating. I've learned a lot about testing standards, and resistor power ratings, probably more than I wanted to know. Apparently there are some rigid standards, and exacting practices people go through to test and certify parts for particular applications. Some of these tests are daunting to say the least!
Test a resistor for 10000 hours?
Meh, not going to happen for me.
That's just one of the current requirements a manufacturer has to meet for the current round of MIL-SPEC testing.
I'm not going to MIL-SPEC certify these resistors. I am however, going to take some suggestions offered to me from the good folks on QRP-L.
From Mike WA8BXN:
Sounds like you want to do some destructive testing. How will you relate that to what should be their normal power rating?Good suggestions!
Rather than doing a destructive test, it might be interesting to find the power that takes the resistor above its rated temperature.
Another test that would be interesting is to measure resistance after cycling power on and off. This is related to checking the next day but is different because I would run through more powered cycles.
What ever tests are done should also be done with resistors of known good quality and specifications.
I'll devise a series of tests, first thing I have to do though is rig up a test jig to measure the actual value of the resistors! My first attempt was a bust due to 9v battery issues on my digital VOM. Once I took care of that, I realized it can be pretty tricky to measure the values of the resistors. They have this thing about holding still. I don't think they like going into the holes that I stuff them in. I'm pretty sure the hot tin/silver amalgam I apply to them upsets them too.
I've only ever had one capacitor blow up on me though... long story, but I now never apply power to a rig with the top off without first putting on my safety glasses, and yes, I had safety glasses on that time!
Wednesday, August 17, 2011
Death to the Resistors!
Chris, K4FH, has been gracious enough to give me 5 of his 100 ohm ebay resistors to test for their actual watt rating.
I would like to solicit comments on the criteria people would consider 'good enough' during this test.
They are marketed as 1/4 watt, 5% tolerance resistors, from ebay. I will try to identify the manufacturer and I will try to acquire a datasheet for them.
Here's the procedure I will use to test them:
1. measure resistance. The measurement shall consist of two readings from my elcheapo centech digital VOM; 1 taken as close to the epoxy body of the resistor as possible, and the other as close to the ends of the resistor leads as possible. Any significant difference in measurement will be confirmed using an analog meter. "Interesting" results will be posted to QRP-L and my blog before I do any experiments on the resistor, and that resistor will be isolated. I will take these measurements at the following times:
a) before doing any testing
b) immediately before testing
c) immediately after testing
d) next day after testing
2. Label resistors, Resistor 1-5, based on their resistance from measurement A, 1 being lowest, 5 being highest. In the event of a tie, the first resistor measured gets the lower number.
3. Test the power dissipation of the resistors. I will probably only do one test a night over the next couple of weeks. I usually get home from work sometime between 04:30 and 05:00 UTC, and spend about 1.5 to 2 hours 'winding down'. I try to be in bed by 06:00/07:00 UTC (2am local time whether daylight savings or not). That gives me about 1 hour to test resistors each night. During the day, I watch my kids, so I won't be able to test them outside of that time frame. Here are the tests:
a) full bench supply for 1 hour: I'll post the exact model number and voltages read before the test, but a 100 ohm resistor across the 13.8 VDC terminals will output 1.9044 watts and draw 138 mA of current, if I done did the math right. I haven't measured the terminal voltage of the supply in a while, and this will be as good an excuse as any to figure out howthe list high quality my 10 year old supply is. Voltage will be measured every 5 minutes during the test. After the test, I will publish my results via QRP-L, and my blog before continuing.
b.) I will set up a series/parallel resistance circuit. The series part will consist of a lump parallel section, and a variable series section. The parallel part will be 5 resistors wide, the test resistor being one of them, and is switched in and out of circuit with another resistor of equal resistance and higher power rating. The circuit will be constructed in such a way that the total power handling of the circuit is at least 4 Watts without the inclusion of our test resistor. Each of the tested resistor will be tested by varying the voltage available to the parallel section until the resistor fails. When the resistor fails, it will be switched out and the 4th resistor in the circuit switched in, the voltage across the fourth resistor will be measured and used to calculate the power dissipated.
Circuit theory: because resistances in parallel share voltage and resistances in series divide voltage, it's possible to use a series/parallel circuit to produce a measurable voltage at the terminals where a test resistor is located. This measurement can be used to record the power dissipated by the resistor at the moment of failure.
My circuit and calculations will be published on my blog and QRP-L before testing for peer review.
c.) After each test I will publish my results within 12 hours of testing.
So there you have it, Death to the Resistors!
thanks everybody!
I would like to solicit comments on the criteria people would consider 'good enough' during this test.
They are marketed as 1/4 watt, 5% tolerance resistors, from ebay. I will try to identify the manufacturer and I will try to acquire a datasheet for them.
Here's the procedure I will use to test them:
1. measure resistance. The measurement shall consist of two readings from my elcheapo centech digital VOM; 1 taken as close to the epoxy body of the resistor as possible, and the other as close to the ends of the resistor leads as possible. Any significant difference in measurement will be confirmed using an analog meter. "Interesting" results will be posted to QRP-L and my blog before I do any experiments on the resistor, and that resistor will be isolated. I will take these measurements at the following times:
a) before doing any testing
b) immediately before testing
c) immediately after testing
d) next day after testing
2. Label resistors, Resistor 1-5, based on their resistance from measurement A, 1 being lowest, 5 being highest. In the event of a tie, the first resistor measured gets the lower number.
3. Test the power dissipation of the resistors. I will probably only do one test a night over the next couple of weeks. I usually get home from work sometime between 04:30 and 05:00 UTC, and spend about 1.5 to 2 hours 'winding down'. I try to be in bed by 06:00/07:00 UTC (2am local time whether daylight savings or not). That gives me about 1 hour to test resistors each night. During the day, I watch my kids, so I won't be able to test them outside of that time frame. Here are the tests:
a) full bench supply for 1 hour: I'll post the exact model number and voltages read before the test, but a 100 ohm resistor across the 13.8 VDC terminals will output 1.9044 watts and draw 138 mA of current, if I done did the math right. I haven't measured the terminal voltage of the supply in a while, and this will be as good an excuse as any to figure out howthe list high quality my 10 year old supply is. Voltage will be measured every 5 minutes during the test. After the test, I will publish my results via QRP-L, and my blog before continuing.
b.) I will set up a series/parallel resistance circuit. The series part will consist of a lump parallel section, and a variable series section. The parallel part will be 5 resistors wide, the test resistor being one of them, and is switched in and out of circuit with another resistor of equal resistance and higher power rating. The circuit will be constructed in such a way that the total power handling of the circuit is at least 4 Watts without the inclusion of our test resistor. Each of the tested resistor will be tested by varying the voltage available to the parallel section until the resistor fails. When the resistor fails, it will be switched out and the 4th resistor in the circuit switched in, the voltage across the fourth resistor will be measured and used to calculate the power dissipated.
Circuit theory: because resistances in parallel share voltage and resistances in series divide voltage, it's possible to use a series/parallel circuit to produce a measurable voltage at the terminals where a test resistor is located. This measurement can be used to record the power dissipated by the resistor at the moment of failure.
My circuit and calculations will be published on my blog and QRP-L before testing for peer review.
c.) After each test I will publish my results within 12 hours of testing.
So there you have it, Death to the Resistors!
thanks everybody!
Thursday, August 11, 2011
Having Cake, and Eating it Too
Yessir, last night was the night that I was able to have my cake and eat it too, and then I was able to have my cake, and eat it too.
First, when I got home, I had cake, chocolate to be exact. There's some left, so I'll probably have more when I get home.
Then, I had radio cake, and ate it too.
First, I gathered my antenna makin' knife, and headed out to the shack, fully intending to make a J-pole for 2m. Then I broke out "The Killer Watt Radio", tuned around, and discovered several people already in conversation, including a M0 that was really strong. I caught the end of the QSO, but he didn't stick around for a tail end QSO. I did some further tuning and heard a CQ, a guy was calling CQ DX, and from his strength and lack of QSB, I thought it was a guy in the North east.
"Let's see who he works," I thought.
Well Imagine my surprise when the call that I copied came back as G0NXA!
"Hey, I'm the DX!" I muttered.
I couldn't resist, and had a pleasant QSO with Giles near Tewkesbury. Thanks Giles! After our first exchange, lightening crashes started coming in, and I was thankful that "TKWR" was hooked up to speakers and not earbuds. Even with the RF gain reduced, it would still rattle the speakers.
With the threat of lightening in my area, we've been under the threat of showers for the last 3 days, I decided to ground my antenna, and QRT for the night, leaving me totally involved in making a 2m J-Pole. The J-Pole was made using 'low loss' 300 ohm tv twinlead, a relic item perhaps, but one you can still get at Radio Shack. I bought this stuff several years ago, it was on sale. jacket and insulation is still in good shape, copper on the inside is bright. Sounds Good 2 go for me!
After testing out the dipole, and trimming to resonance for the part of the band that I wanted, I had another voice QSO via the K4LKL repeater with Rich, KJ4INW. He was using his handie-talkie and sounded pretty good. We talked a few minutes, until it was bed time for me.
I'll have to do a review of the j-pole tonight sometime after I get home from work. I want to check into the K4LKL net. I built the j-pole with that net in mind, the rubber duck don't work from my desk.
First, when I got home, I had cake, chocolate to be exact. There's some left, so I'll probably have more when I get home.
Then, I had radio cake, and ate it too.
First, I gathered my antenna makin' knife, and headed out to the shack, fully intending to make a J-pole for 2m. Then I broke out "The Killer Watt Radio", tuned around, and discovered several people already in conversation, including a M0 that was really strong. I caught the end of the QSO, but he didn't stick around for a tail end QSO. I did some further tuning and heard a CQ, a guy was calling CQ DX, and from his strength and lack of QSB, I thought it was a guy in the North east.
"Let's see who he works," I thought.
Well Imagine my surprise when the call that I copied came back as G0NXA!
"Hey, I'm the DX!" I muttered.
I couldn't resist, and had a pleasant QSO with Giles near Tewkesbury. Thanks Giles! After our first exchange, lightening crashes started coming in, and I was thankful that "TKWR" was hooked up to speakers and not earbuds. Even with the RF gain reduced, it would still rattle the speakers.
With the threat of lightening in my area, we've been under the threat of showers for the last 3 days, I decided to ground my antenna, and QRT for the night, leaving me totally involved in making a 2m J-Pole. The J-Pole was made using 'low loss' 300 ohm tv twinlead, a relic item perhaps, but one you can still get at Radio Shack. I bought this stuff several years ago, it was on sale. jacket and insulation is still in good shape, copper on the inside is bright. Sounds Good 2 go for me!
After testing out the dipole, and trimming to resonance for the part of the band that I wanted, I had another voice QSO via the K4LKL repeater with Rich, KJ4INW. He was using his handie-talkie and sounded pretty good. We talked a few minutes, until it was bed time for me.
I'll have to do a review of the j-pole tonight sometime after I get home from work. I want to check into the K4LKL net. I built the j-pole with that net in mind, the rubber duck don't work from my desk.
Wednesday, August 10, 2011
Nugget of RF Truth...
So last night, I honestly was trying to build a J-Pole, I even got new razors for cutting insulation off twinlead, but alas, it was not to be, several things worked together for the greater good. I needed the J-Pole so that I can check into the ARES net tonite from work, my lil' rubberduck just ain't got the ERP* necessary to facilitate communication. I don't have a J-Pole, but I do have a new logged contact in the log book! Let me tell you what happened.
It's summertime, and you know what that means, summertime thunderstorms that shatter all hopes of reasonable HF propagation below 10MHz. Well, not exactly, not all the time. When I turned on The Killer Watt Radio**, the band was noisy, but not nearly as noisy as it's been the last few nights. I also didn't hear a lot of activity. That's not entirely unexpected, I mean, it's one in the morning local time on a weekday. Plus, the Space Weather Guessers were talking about some solar flares, and geomagnetic storms. Things looked like a total downer.
Then I heard a loud clear CQ, it was David, WD8CW in Huntington, WV. His sig was strong, but there was some QSB, I decided to call him back and we had a reasonable QSO given the conditions. After we signed, I spun the dial again, there was some digital activity, but no one was calling CQ at that point in time. I looked at the clock, and found out it was after 2am. time for bed! so no atenna, but I did get a 359 from WV with a 1 watt transmission feeding a dipole during a time of crummy conditions.
That, my friends, is why I love ham radio, crazy is perfectly acceptable here.
* ERP = Effective Radiated Power
** "The Killer Watt Radio" is a Small Wonders Labs SW-40+. It transmits 1 watt of blazing power, but it's one killer watt!
It's summertime, and you know what that means, summertime thunderstorms that shatter all hopes of reasonable HF propagation below 10MHz. Well, not exactly, not all the time. When I turned on The Killer Watt Radio**, the band was noisy, but not nearly as noisy as it's been the last few nights. I also didn't hear a lot of activity. That's not entirely unexpected, I mean, it's one in the morning local time on a weekday. Plus, the Space Weather Guessers were talking about some solar flares, and geomagnetic storms. Things looked like a total downer.
Then I heard a loud clear CQ, it was David, WD8CW in Huntington, WV. His sig was strong, but there was some QSB, I decided to call him back and we had a reasonable QSO given the conditions. After we signed, I spun the dial again, there was some digital activity, but no one was calling CQ at that point in time. I looked at the clock, and found out it was after 2am. time for bed! so no atenna, but I did get a 359 from WV with a 1 watt transmission feeding a dipole during a time of crummy conditions.
That, my friends, is why I love ham radio, crazy is perfectly acceptable here.
* ERP = Effective Radiated Power
** "The Killer Watt Radio" is a Small Wonders Labs SW-40+. It transmits 1 watt of blazing power, but it's one killer watt!
Tuesday, August 9, 2011
Well, Looks Like I have Blog Content for the Next Six Months Plus!
ARRL had a special, rejoin, get a book.
I got a book!
Any requests?
I got a book!
 | ||
| hehe! |
Any requests?
Monday, August 8, 2011
'Nother Awesome Portable Antenna Design - The St Louis Vertical
Whereas the W3EDP is my favorite antler, this one here is probably the one I use most often when I am in the field, mainly because it's so easy to deploy.
This is an antenna I first saw at a NoGA QRP meeting in Atlanta, when I first saw it, I thought to myself "Well ain't this the Bee's Knees."
The antenna is called a St Louis Vertical, named by the St Louis QRP Society, and enshrined at the American QRP Club.
This antenna is:
- Portable
- Easy to build
- Easy to find the parts to build it!
- Cheap (!kinda, not nearly as cheap as it was!)
- Multi band
Take a good long look at the antenna, and you will understand that it is meant to be a bottom loaded 'short' vertical. Here's the math though:
1. Do the Math, 1/4 wave vertical on:
40m: 33.29' (7.030 MHz)
30m: 23.15' (10.106 MHz
20m: 16.64' (14.060 MHz)
17m: 12.93' (18.096 MHz)
15m: 11.11' (21.060 MHz)
12m: 9.40' (24.906 MHz)
10m: 8.34' (28.060 MHz)
The only bands that this antenna is short on are 40, and 30M!
What this means is that the antenna will actually be LONG on 20M and up.
Long antennas get funny radiation patterns, especially as the frequencies approach multiples of wavelengths. Basically what happens is the signal stops shooting out (perpendicular to the orientation of the antenna), and starts shooting up. When the antenna is horizontal, that's not an issue, but when the antenna is vertical, it basically means the signal gets shot straight up into the air. Not desirable!
One simple solution to this problem is to use a shorter wire, or leave out the bottom loading coil. It's pretty easy to take a 20' fishing pole and make a quarter-wavelength long vertical out of it for frequencies greater than 14 MHz.
What I need to do to make it better on the higher bands, is find a way to measure the inductance of the coil, and working from there calculate a whip length, and adjust. Hmmm, the coil body is so long, that I have a feeling that trying to use the time honored method of measuring the resonant frequency when paralleled with a known capacitance value could lead to screwy values. Maybe I need to measure series resonance instead...
I'll take anyone's help here.
Another thing that is slightly buggy sometimes, and can cause you no end of trouble if you aren't aware, is that best performance is obtained when you keep the feedline off the ground. If the feedline can dance around, then you will notice strange SWR behavior. I suspect that there is a large amount of signal loss to the ground if the line is allowed to rest on it. I know signals sound louder when the line is elevated in some fashion.
The St Louis Vertical, took apart, and ready for transport:
Let me explain the parts:
You see in this picture, a "Sunny Day Fishing Pole" that's the brand name I believe. It extends to twenty feet. Wrapped around the fishing line holder on this pole is enough stranded hookup wire to go from the top end of the coil to the top end of the fishing pole, around 16 feet. It connects via an alligator clip. The four bundles of wire are the radials for the antenna. They are made of 3 conductor antenna rotator wire, such as you find at Radio Shack. The radials are made by attaching all three wires to a ring terminal connector and then nipping out an inch of the individual wires at various lengths along the way, making the longest 1/4 wavelength on the lowest frequency. You should apply electrical tape where you nip the wires to keep water out of the wire, and to keep the wires from pulling apart on a snag. These wires are cut for 40, 20, and 15 meters, but they'll work 40-10 no problem. You're using a tuner anyway! The long spike is used to hold the pole up. I use a hanger on the spike to keep the pole off the ground, and to also serve as a common lug for the radials. The feedline is 300ohm twinlead. The black alligator clip goes to the ground side, the red alligator clip goes to the radiator side. The banana plugs go to my antenna tuner, usually an Emtech ZM-2. I love that little thing!
I'm going to try something different with this antenna, namely, I'm contemplating elevating the antenna in some shape or form and making a permanent antenna out of it. This version of the SLV is traditionally fed with twin lead so that you can use a tuner to make the antenna work. I might just keep that feature, maybe use the more robust wireman feedline, or something.
There is another version of the SLV out there, Here's a link to a "For Sale" article http://www.eham.net/classifieds/detail/341186 about it. It's a pretty good little antenna too, a lot of hams on the old QRP-L reflector had one back around 200-2001. I actually bought one from a guy on QRP-L in late 2000, but had the loading coil stolen from me before I had a chance to use it. It was right after I got my general ticket too. I had all sorts of plans in my head about going camping with it. I bought some aluminum ground wire to make a new coil, but haven't made the time to do that yet. There's always a project going on at my shack!
*******EDIT*********
I received this email from Dave, NF0R, the designer of the SLV. He posted it to the QRP-L newsgroup, and I have reproduced it here with his permission:
Hello GB,
It appears you are having fun with the SLV. I enjoyed reading your comments and observations on the Blogspot over coffee. I'm retired now and have time have time to put a reply and update together this morning
I designed the SLV (1996?) to be a quick, lightweight and inexpensive vertical. It was for folks wanting to work a little portable QRP, make a few contacts and go back home. No heroics! Just enjoy radio in a portable setting without spending time finding a suitable spot for a wire antenna and still more time installing it. To that end I made it multiband with the continuous coil and a tuner to take advantage of propagation. It's no fun going out with a monoband homebrew rig and finding no signals on your band of choice. I got the idea for using the collapsible fiberglass pole from W7ZOI in Solid State Design.
Referring to your Blogspot you can use coax if you wish to avoid SWR issues associated with wet twinlead. Ditto for stiff line that tends to move around. But It's not a big deal - just tweak the tuner and gone. You can use twinax or parallel runs of RG-58 or even RG-174 if you wish. High-performance with a compromise antenna is always a bit of a battle. That said I tend to favor convenience for portable and working someone (anyone?) instead chasing
the coasts or DX.
I'm not much on elevating the twinlead feedline. As a matter if fact I may have not even tried that experiment. An elevated balanced feedline could add horizontal polarization sort of like an up & outer. But being so close to the ground I doubt it's practicality except for NVIS and prefer to rely on vertical polarization.
I have no idea what inductance the coil measures. It's really a moot point when feedling with balanced line. I filled the base of the SD-20 pole with twinlead because I had enough line in the Radio Shack package to do that. The wet thumb and/or more-is-better school of engineering if you will. It also allowed me to work 80M with the SLV a few times though I can't recommend
that.
The W6MMA wire coil is certainly more efficient due to it's elevated location. However, that particular product is not something you can duplicate without equipment and expertise. You can duplicate it's efficiency by winding a bare wire coil on a section of a child's round float tube and slipping that on thepole. That excellent and elegantly simple design was created by N0TFI (now AE0CW). His coil is a personal favorite of mine. It's real ham radio!
Note that with any tapped multiband coil you may have to swap out upper radiators when some bands change. This is not an issue with the twinlead coil. I prefer to operate when running portable and spend as little time as possible installing and/or adjusting the antenna. My design limit for installs is five minutes tops! Lately I have been running portable with a St. Louis Micro Loop where the set-up time is thirty seconds tops or about the time it takes to walk from the car trunk to a picnic table. For that and other reasons I really enjoy fooling around with that antenna.
If I decided to re-do the SLV today I would use N0TFI's excellent homebrew coil mounted head-high for convenience. Setting aside most mono and dual-banders today's QRP xcvrs by and large feature on-board tuners. You can get a fairly close match with taps on the coil and touch up the match with the automatic tuner so the rig sees 50 ohms.
My other option would be to homebrew a tapped air-core St. Louis Coil for the SLV which I have already done in multi-band and mono-band versions. These elevated configurations produce very efficient antennas. I also use my version of W6MMA's built-up SLV mount. It employs a pcb feedpoint disk for attaching St. Louis Radials and protects feedline
connections in wet weather.
There were no integrated tuners in commercial QRP xcvrs when the SLV was designed. Hitting tap points on a coil when portable is inconsistent The antenna was intended to be erected in any number of locations and each site is a different RF environment. Having said that there may be
some who still enjoy running back and forth between the antenna and the rig to get a low reading on the SWR bridge.For that and practical reasons I like to keep my portable vertical feedlines short - typically 12-18 feet depending on the lowest design band.
I increased the original SLV's folded radials from three to eight for better efficiency on 30M and 40M. I dropped the notching after several EE's kindly took time to explain how ground proximity affected the resonance of radials laying on the ground. Those folded radials evolved into St. Louis Radials which use ribbon cable. They put a lot of wire (metal) under the antenna which seems to be helpful judging from several field strength experiments. However,
the main reason for their existence is to minimize the hassle with single wire radials and those annoying tangling problems out in the field. Grrrr!
Being fairly supple the stranded-wire ribbon radials are much easier to store, carry and deploy than twinlead. On the trail I coil in groups of three and carry in a round rubber container in the backpack. Otherwise I gather them right below the alligator clips, lower into a cloth bag and
store in the car trunk.
I actually use 1/8th wave radials these days for my portable antennas including the St. Louis Vertical, St. Louis Vest Pocket Vertical, St. Louis Express and several more unpublished designs. These short radials work remarkably and were suggested to me by KK6MC, Jim Duffy, a.k.a. Dr. Megacycle'
I have no qualms running a 10' tall SLVPV on 30M and 40M for chasing DX or milliwatting with eight to a dozen abbreviated ribbon radials under it. For all of these portable verticals the footprint ends up being very small.
Thanks very much for your post about my old SLV. I certainly enjoyed reading it and appreciate your time and effort. I hope you find my comments helpful.
Best regards,
Dave Gauding, NF0R
Ain't this a fun hobby?
Saturday, August 6, 2011
Stealthy Radio Antenna.. the Gutter!
There's a lot of great things about being a HAM radio operator.
I've served the public during sporting evens, and emergencies.
I've had a lot of fun talking to people all over the world using all manners of methods of communication.
I have to say though, that thing that I like most about it is that HAM radio, no matter what aspect of the hobby you enjoy the most, is a very hands on hobby. My wife can tell you I'm always plottin' something to get another antenna in the trees, or saving for a radio to build. Some places and people are not friendly to my hobby though. There's entire communities that force people to live antenna free. I refuse to own propery in such a place. I do, however sympathize with people who do live in deed restricted, covenant restricted communites, and do my best to help others get on the air despite, or in spite of whatever restrictions they face.
A buddy of mine once lived in an apartment, and had just got his General Ticket, so he had access to the HF bands. Apartments are notoriously antenna unfriendly, so I helped him set up his gutters as an antenna. Let me tell you how we did it.
CAVEAT!
If you decide to do something similar, use caution! This is for power not to exceed 100 watts. First of all, you should never use more power than you need to communicate. Secondly, RF can and does start fires, it's how microwave ovens warm your Hotpockets. Plus, even at 100 watts, my buddy would sometimes experience rf in his shack, or interference with the TV and telephone. The simplest solution to this is to turn the power down.
So with that in mind, let's get our minds on the gutters.
Notice, I said, on the gutters, not in the gutter.
Gutters, if they are made of metal, can carry RF, and they can do it reasonably well, if some things are kept in mind. They basically function as a random length wire antenna, although if you have the space for it, and do a little planning and experimentation, you could possibly create a system resonant on a particular frequency. Here are the rules about using METAL gutters as antennas:
1. ELECTRICALLY connect the pieces. Most gutter pieces are either friction fitted, or connected together via a small screw. This is a mechanical connection, and is not good enough for RF. RF needs to see the pieces as one piece electrically, so there needs to be a low resistance connection between the pieces. As it stands, they are loosely electrically connected joints, and can actually act as product detectors, meaning they they are small bits of radios themselves! This results in all kinds of noise and interference on your received signal. Fortunately this is easy to fix, but it does take work. This is also good information for you to store away when you want to install a mobile radio, as you will want to electrically connect the various body panels on your vehicle.
To connect gutter pieces you will need:
2. Create a good ground plane. Unless you live near the ocean, your ground plane stinks. Shooting a ground rod into the ground near the spout where you will be feeding your antenna is one thing you can do. It will at least help give you some lightening safety. Hooking some radials up to that rod would be even better. Hook up at least 4, and space them an equidistance apart out in the front. Make sure they are at least a quarter-wavelength long on your lowest frequency of operation. Because that can be 66' for frequencies in the 3.5 MHz range, you may need to get creative on where they go, and how they sprawl out. I use a hand operated sidewalk edger to make a small slit in the ground, that can be used to bury the ground radial. You'll need to find some similar way of hiding the radials. When you connect the ground braid from the coax pigtail to the ground system of the antenna, use some more of the conductive grease.
3. Did you use the conductive grease? If not go back and use it! Water makes copper corrode quicker, and copper braid readily absorbs water. Corroded copper does not conduct RF well. Because gutters are designed to carry water, it's important to try and make the connections as waterproof as possible. The conductive grease helps do that, and it helps make the electrical connection better. USING REGULAR GREASE IS NOT RECOMMENDED! regular grease will act as an electrical insulator. That's the opposite of what we want to do.
4. Run as short a line as possible from the antenna's pigtail to an antenna matching device. You may or maynot need a balun. The antenna matching device should be grounded to the same point as the antenna, although if you can't do that, don't worry. Just get it grounded.
That's how you make a gutter system into an antenna. At my buddy's apartment, we stealthily connected the pieces of a downspout together electrically, and it wasn't easy. Fortunately, the downspout could be accessed from a stairwell. He had a great time on HF with 100 watts and less, but had a better time with a stealth longwire. That's for another post though...
EDIT: Links for other downspout antennas will go here as people get them to me!
WB3GCK's antenna
I've served the public during sporting evens, and emergencies.
I've had a lot of fun talking to people all over the world using all manners of methods of communication.
I have to say though, that thing that I like most about it is that HAM radio, no matter what aspect of the hobby you enjoy the most, is a very hands on hobby. My wife can tell you I'm always plottin' something to get another antenna in the trees, or saving for a radio to build. Some places and people are not friendly to my hobby though. There's entire communities that force people to live antenna free. I refuse to own propery in such a place. I do, however sympathize with people who do live in deed restricted, covenant restricted communites, and do my best to help others get on the air despite, or in spite of whatever restrictions they face.
A buddy of mine once lived in an apartment, and had just got his General Ticket, so he had access to the HF bands. Apartments are notoriously antenna unfriendly, so I helped him set up his gutters as an antenna. Let me tell you how we did it.
CAVEAT!
If you decide to do something similar, use caution! This is for power not to exceed 100 watts. First of all, you should never use more power than you need to communicate. Secondly, RF can and does start fires, it's how microwave ovens warm your Hotpockets. Plus, even at 100 watts, my buddy would sometimes experience rf in his shack, or interference with the TV and telephone. The simplest solution to this is to turn the power down.
Notice, I said, on the gutters, not in the gutter.
Gutters, if they are made of metal, can carry RF, and they can do it reasonably well, if some things are kept in mind. They basically function as a random length wire antenna, although if you have the space for it, and do a little planning and experimentation, you could possibly create a system resonant on a particular frequency. Here are the rules about using METAL gutters as antennas:
1. ELECTRICALLY connect the pieces. Most gutter pieces are either friction fitted, or connected together via a small screw. This is a mechanical connection, and is not good enough for RF. RF needs to see the pieces as one piece electrically, so there needs to be a low resistance connection between the pieces. As it stands, they are loosely electrically connected joints, and can actually act as product detectors, meaning they they are small bits of radios themselves! This results in all kinds of noise and interference on your received signal. Fortunately this is easy to fix, but it does take work. This is also good information for you to store away when you want to install a mobile radio, as you will want to electrically connect the various body panels on your vehicle.
To connect gutter pieces you will need:
- self tapping screws (many)
- A machine screw
- 2 washers (for machine screw)
- locking nut (for machine screw)
- sandpaper
- copper bearing conductive grease.
- A coax pigtail, one end with an SO-239 connector, the other should have the braid and center conductor seperated for about 6-10 inches.
- ohm meter
4. Run as short a line as possible from the antenna's pigtail to an antenna matching device. You may or maynot need a balun. The antenna matching device should be grounded to the same point as the antenna, although if you can't do that, don't worry. Just get it grounded.
That's how you make a gutter system into an antenna. At my buddy's apartment, we stealthily connected the pieces of a downspout together electrically, and it wasn't easy. Fortunately, the downspout could be accessed from a stairwell. He had a great time on HF with 100 watts and less, but had a better time with a stealth longwire. That's for another post though...
EDIT: Links for other downspout antennas will go here as people get them to me!
WB3GCK's antenna
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