OSCAR News - August, 2ØØ8
The next OSCAR meeting is 09-Aug @ 9:00 AM, the second Saturday of the month. Meetings are held at the Happy Chef at US-14 West and I-35.
The next SKYWARN meeting is 19-Aug @ 7:00 PM, the third Tuesday of the month. Meetings are held at the Owatonna Fire Station.
The Dakota Division Convention is being hosted by the Rochester ARC. It is scheduled for Friday 08-Aug thru Sun 10-Aug at the University Center. There will be an ARES program and hamfest on Saturday.
News From Albert Lea
The Albert Lea Amateur Radio Club will host a Fox Hunt on 08-Aug at 1:00 PM. The hunt will be held at Pickrel Lake Park, 1.5 miles South of Albert Lea on U S Rt. 69. The Club Picnic follows at 6 pm. Bring your own meat and beverage along with a dish to pass. Contact Tom Lehto 866-556-9251 (cell) for any additional information.
Jim WDØCNL put the combination Austin/Albert Lea field day pictures on the ALARC net page. The field day was a success. All who attended had a good time and are looking forward to next year.
OSCAR Field Day Final
The final tally for Field Day is 459 CW QSOs , 489 Phone QSOs, and 11 Digital QSOs. QSO points totaled 2,858, combined with the 550 bonus points for emergency power, public location, publicity, ??? QSL cards were received from:
- K2DUX for a 10 meter phone contact on 29-Jun @ 14:22Z.
- KC2AWX for a 10 meter phone contact on 29-Jun @ 10:15Z.
- AJ5H for a 20 meter CW contact on 28-Jun @ 19:58Z.
Steele County Emergency Management is planning a drill for Friday, 12-Sep. This is a multi-organization drill that includes a RACES operation. The goal for RACES is to establish a digital connection to transfer information between organizations. Contact Tom NØUW if you can help with preparing for and/or participating in the drill.
Radio Shack Recall
The recall involves Radio Shack 13.8V DC Power Supplies, catalog numbers 22-507 and 22-508 with date codes from 08A04 through 01A08. Date code format is MMAYY where MM is the month and YY is the year. The catalog number and date code are located on the back of the power supply. Power Supplies with a green dot on the product and the product's packaging have already been repaired and are not included in the recall. They were sold at Radio Shack stores nationwide from October 2004 through January 2008 for between $50 and $85. The recall notice can be seen at the
CPSC. You can use the site to look at past recalls and sign up to receive am e-mail whenever recall announcements are made.
A recent newsletter for Citizen Corp managers highlighted the need to develop partnerships with Amateur Radio. The suggestions include using Amateur Radio for communications and helping Citizen Corp volunteers earn their Amateur Radio license. It is good to recognize that Steele County is once again ahead of the curve. OSCAR has contributed to the development of volunteer resources through the Technician classes offered over the past several years. Steele County appreciates the support.
From AR Newsline
The July issue of Popular Communications takes an in depth look at why the once popular form of communications is suddenly making a comeback among the driving public. The article titled Ready to Roll With CB Radio vsuggets that the C-B operations of 2008 bring with it a more mature mode of communicating. It also dispels many myths about 11 meter operation and highlights some of the legal gear that's available in todays 11 meter marketplace.
When Networks Fail
From PC World
Normally, in a time of crisis, an "amateur" is not the first person you might call. But when communications networks go down, amateur radio operators -- or hams -- and their gear can get communities connected to the outside world via the radio waves.
This is the first paragraph in a nice article in PC World magazine. The
article includes metnion of ARES, MARS, and digital modes.
From AR Newsline
Apparently, ham radio has a cameo role in the recently released Get Smart movie. At one point, Maxwell Smart commandeers a car from another agent,. There under the dash, is a 2-meter rig, tuned to 146.91 MHz. We see it twice, since the agent he took the car from calls him on the radio and the camera flashes back to the rig.
National Incident Management System (NIMS)
Emergency communications using Amateur Radio in Steele County are moving to a dual RACES/ARES organization. It becomes increasingly important for hams to have the requisite trainign in NIMS. The two basic NIMS courses can be taken on-line, IS-700 and
IS-100. Despite the numbering sequence, IS-700 is the first course. Although the estimate is 3 hours to complete the course, it can be done in as little as 1 hour. Download the 25-question final exam as a .pdf. The answers can be searched for while taking the course.
Be sure to let Tom NØUW know when you've completed any NIMS course.
The Other Digial TV Transition
There actually are two analog-to-digital transitions going on. You've heard a lot about the broadcast changeover. Little is being said about the analog cable to digital cable transition. The cable version of the analog-to-digital jump will impact anyone who takes a coaxial cable line from the wall and plugs it directly into an analog TV set.
There are 26.5 million cable consumers who subscribe to analog service. A Federal Communications Commission Consumer Advisory says “Cable companies are not required to switch their privately-owned systems from analog service to digital service,” before warning consumers that cable companies may make the switch anyway, and may change consumers extra for the necessary equipment. Legally, cable providers need only continue to transmit analog versions of broadcast channels (generally, the familiar channels 2-13) for the next three years.
The cable industry plans to shut down those analog signals in an effort to reclaim space that can be used for new services, such as additional high-definition channels. Comcast, the largest cable provider, said it will begin dropping analog signals in 20 percent of its markets by the end of this year. There will be no government coupons to help pay for new set-top boxes or converters.
White Space Spectrum
The Federal Communication Commission’s Office of Engineering and Technology (OET) announced that it will begin field testing the performance of prototype television white space devices (WSDs). The Commission is conducting tests of prototype white spaces devices as part of its rule making to consider authorizing the operation of new low power devices in the TV broadcast spectrum at locations where individual channels/frequencies are not being used for authorized services (TV white spaces) The field tests will mainly be conducted in Maryland and Washington D.C., with a couple wireless microphone tests planned at undetermined sports and entertainment venues.
It is amazing what can be found on GoogleMaps
Hands-Free vs. Handheld
From Science Daily
The July Newsletter containecd an article on hands-free communication. Related research in another article suggests that hands-free cellphones are not safer and indeed may even be more dangerous than hand-held. The research suggts that talking on the phone, regardless of phone type, has negative impacts on performance, especially when the driver is confronted by complex or unpredictable situations. Performance while using a hands-free phone was rarely found to be better than that using a hand-held phone.Some studies found drivers compensate for the harmful effects of cellphone use when using a hand-held phone—by driving slower or pulling over to finish a call—but neglect to do so when using a hands-free phone. One Canadian study demonstrated that talking on a cellphone while driving increased the risk of an accident four-fold, and that whether the phone was hand held or hands free made no difference to the risk. The researcher concludes "When you’re talking on the phone, your attention is on the conversation. You may be looking at things but that doesn’t mean you’re processing that information."
Now go back to your basic electronics books on amplifiers and relearn the difference between A, B, AB, C, and D class amplifiers. Most power amplifiers in use are Class AB, which run at between 15 and 40 percent efficiency. That is why you should have a 10-amp power supply for your 50-watt rig (I = P/E = 50 / 13.4 = 3.7A). Class D amplifier efficiency runs at between 40 and 85 percent. Although more efficient, Class D amplifiers were once thought to be appropriate only for low-end audio devices like cellphones. They have started showing up in everything from flat panel televisions and computers to high-end sound systems.
Traditional amplifiers use electrical resistance, similar to a dimmer switch that controls the light. Those resistors turn valuable electricity into unwanted heat, which necessitates bulkier design. Since a Class D amplifier has an output that switches between on and off. The difference is not unlike an analog power supply and an electronic switching power supply. Like a switching power supply, the electrical noise created by the switching must be filtered out.
The big advantage with Class D amplifiers is that they're much more efficient from an energy usage point of view than conventional Class AB amplifiers. The advantages of that efficiency then ripple through the entire system power supplies can be smaller, longer battery life, less heat -- all of which makes the equipment then smaller and lighter.
From Science Daily
The first thing an alien race is likely to hear from Earth is chirps and whistles, a bit like R2-D2, the robot from Star Wars. In reality, they are the sounds that accompany the aurora. Scientists call this radio emission the Auroral Kilometric Radiation (AKR). AKR was discovered by satellites in the early 1970s. It is blocked from reaching the ground by the ionosphere, the upper reaches of Earth’s atmosphere. This is just as well because otherwise it would overwhelm the transmissions from all our radio stations. It is 10 000 times more intense than even the strongest military radar signal. They are generated high above the Earth, by the same shaft of solar particles that then causes an aurora to light the sky beneath. For decades, astronomers had assumed that these radio waves travelled out into space in an ever-widening cone.
ESA’s Cluster mission has four nearly identical spacecraft flying in formation. Scientists precisely time when the AKR washed over each of the satellites, triangulating the points of origin similar to GPS navigation. By analysing 12 000 separate bursts of AKR, a team of astronomers determined that the AKR is beamed into space in a narrow plane. This is like placing a mask over the torch with just a small slit in the middle for light to escape. For each of the AKR bursts they analysed, the astronomers pinpointed its point of origin to regions in Earth’s magnetic field just a few tens of kilometres in size. These were located a few thousand kilometres above where the light of the aurora is formed. Spacecraft have seen aurorae and detected AKR on Jupiter and Saturn, the two largest gas giants in our Solar System.
Although looking for AKR from extrasolar planets will require much larger radio telescopes than are currently available, these instruments are on the drawing boards. Once these planets have been identified, the AKR can be monitored for how it winks on and off, allowing astronomers to calculate how long the planet takes to rotate. It also provides new routes of investigation into the magnetic fields of other stars, many of which have magnetic fields thousands of times stronger than the Sun. They too, will produce radiation similar to AKR and these can be monitored.
From Science Daily
LED lights are about as efficient as compact fluorescent lights (CFL). Unfortunately, CFL lighting contains harmful mercury. LED lights now on the market are expensive, in part, because they are created on a sapphire substrate. Sapphire-based LEDs require a separate mirror-like collector to reflect light that ordinarily would be lost. Researchers believe they solved this problem by developing a technique to create LEDs on low-cost, metal-coated silicon wafers. In the new silicon-based LED, engineers "metallized" the silicon substrate with a built-in reflective layer of zirconium nitride. Ordinarily, zirconium nitride is unstable in the presence of silicon. This problem was solved by placing an insulating layer of aluminum nitride between the silicon substrate and the zirconium nitride. Using silicon will enable industry to "scale up" the process. Affordable LED lights could be on the market within two years.
GAP Titan Vertical. No Trap Center-Fed Vertical - Offers wide bandwidth on 80-10 meters including 12, 17, and 30 meter WARC bands. New in AES catalog $399. Sale $200. The antenna was assembled but never erected - no corrosion on the aluminum. Partially disassembled into bundles. Longest section is 106". Will deliver to Owatonna. N1UW@arrl.net