The Summit Sentinel
Volume 21.11
November 1997
Dedicated to the Amateur Radio Service and Emergency Communications
Las Cumbres Amateur Radio Club, P.O. Box 2451, Cupertino, CA 95015

What's New!


On the Horizon

  • November 12, Board Meeting, 7:00p, American Legion Hall, Santa Clara
  • November 18, General Meeting, 7:30p, Oak Room HP Cupertino, Brad Wyatt K6WR will present the ARRL Pacific Region update.
  • November 29, Breakfast Meeting, 8:00a, Just Breakfast, Lawrence and Homestead, Santa Clara.
  • December 8, Board Meeting, 7:00p, American Legion Hall, Santa Clara

Club eats breakfast!

by Tom K6KMT

Yet another 5th Saturday went by in August. And with that another LCARC breakfast (or as "Fred" likes to announce "... Brake Fast!"). The event was held in the usual spot, at Just Breakfasts in Santa Clara, with good attendance at about 20 and in our own private banquet room.

The discussion was lively with everything from bike-mobile to duplexers to repeater coordination (and all that was just at my end of the table). Breakfast was served hot, timely and with a smile. When a single check arrived (opps!), Bob W6OPO, sharpened his arithmetic skills learned as LCARC treasurer, took charge, and handled the situation.

The real action happened in the parking lot after breakfast. Show'n tell included home brew duplexers by Frank W6SZS and Dan K6PRK. Mobile antenna installations were discussed and pointed out. John KD6KNF showed off his new "ride," a brand-new, shinny, large-displacment candy apple red V twin Honda (Those one-handed wheelies while talking on the HT were impressive John!).

I think everyone had a good time! Don't miss it next time (November 29th corner of Lawrence Expressway and Homestead Road, 8am). Talk-in K6FB/R. Bring your latest ham project, significant other, new rig or ?.

Tom, KD6KMT


The ramblings of K6PRK

by Dan K6PRK

A bunch of things have been happening with the technical committee in the past 6 months. As you are all aware of the 2 meter and 440 link is up and running very well. A month ago Frank W6SZS, Bob W6OPO and myself went up to Black Mountain to find out why the 440 repeater quit. When we opened the door to the vault an acrid odor of burned PC board was present. Since the 440 was down we went directly to the 12v 20A-switcher power supply. We were not very surprised to find the power supply had burnt up.

To digress a little, for several years we were trying to make a couple of Motorola Micor's work for the 420 link between Black Mountain and Las Cumbres. The Micor's worked very poorly. Recently we replaced both Micor's with Yaesu 420 link radios. The old Micor was still mounted in the rack at Black Mountain and the new Yaesu radio was using the power supply outboard on the old Micor chassis. Several months ago we got a new power supply to be used inboard on the new link radio.

Since everything was "working" OK with the old power supply, we put off "finishing the installation" on Black Mountain. The power supply failure MADE us finish the installation.

The 440-repeater/link radio is all in one rack mounted chassis. Frank W6SZS donated the rack mounted chassis pan. I did all the metal work and painting. The duplexers for the 440 repeater and the link power supply are also mounted on the chassis. The installation came out to the high standards that are demanded by the commercial repeater site. We spent a couple of hours to complete the installation.

The old link radio was removed and will see no more service (Thank goodness). The 12volt 20-amp switching power supply is a total loss (anyone want a doorstop, a challenge, it's yours for the asking).

What's new!

Some new happenings at Las Cumbres are:

  • Major shack and surrounding area clean up led by Jey KQ6DK.
  • A second equipment rack was obtained and installed by myself, just in time for...
  • Jim KN6PE's TCP/IP packet station installation (in the new equipment rack).
  • Installation of a 1.2 Ghz repeater (W6SZS/R)
  • Surplus bandpass filters modified for use at the Las Cumbres site for link radios

    The old packet radio is still in operation as usual. The TCP/IP packet radio station is new and additional to the old system.

    Frank W6SZS built the 1.2 repeater and installed it. A test is being made to determine how much signal attenuation is present with an antenna mounted at low level. It is planned to put the antenna on top of a 100 foot tree.

    There was a couple of donated surplus cavity filters in the TCC stuff. The filters were tuned for 325 Mhz. They weren't too useful to the club at those frequencies. The club needs a cavity filter to reduce de-sense from the 2 link radio antennas being so close together.

    I have a new lathe and was having a good time machining the filters to perform at 420 Mhz. One filter, when attached to the link receiver reduces the transmitter signal by -28DB with a loss at the receive frequency of approx. 2.2DB. The other filter was modified to do the same thing with a reduction of 15DB to the transmit frequency and a loss of only 0.9DB at the receive frequency. We'll try both filters and, if the lower loss one works, it will be left on the receive side. Currently we are using the old 440 antenna at the top of a 100-foot tree for the 420 receive.

    Speaking of Distortion...

    There have been some comments by new users of our repeater system of bad audio from the 2-meter or 440 sides. I've heard some of the comments myself. The usual comments are, "they ought to do something about the repeater audio, it is badly distorted." I monitor the repeater during my workday and have checked the input when comments are made. Invariably the input audio is just as badly distorted. What goes into the repeater comes out (in computer language, GARBAGE IN GARBAGE OUT)! If the input is on 2 meters, the 440 audio has a slight tail off of the high frequency audio components and sounds better than the 2-meter side when a station hits his audio too hard.

    There is an audio level problem with nearly all of the imported radios. The mike audio level, from most manufacturers seems to be factory set for a talking distance of about 1-foot from the mike. The deviation limits of the imported radios are usually set properly when new. When a new ham gets his radio and talks close to the mike in a loud voice, the deviation limiter will chop off the excess audio. The result is distortion. I have suggested that they back off from the mike to cure the distortion and have had mixed results. Some users will back away for a few transmissions and then eat the mike again (Hmmm, maybe I do that a little too).

    The audio levels are set up on our repeater to compand the audio. This allows lower level audio inputs to have a reasonably good audio level out of our repeater. As long as the FM deviation does not exceed 4.5 Khz the audio quality will be good. Equalizing audio levels at the repeater means that you as a listener won't have to ride the volume control on your receiver as much.

    On the downside, if you are mobile and have the window open, the background noise sometimes can be companded as high as your voice level making you hard to understand. I have used repeaters without companding and someone with a weak voice in the group can hardly be heard and the loud voices (like mine) will bust your eardrums.

    Another problem that I've seen is one station who has a full quieting signal will pop in and out of the repeater a number of times during the transmission. Then the person who is doing this is asked to repeat parts of his transmission. Obligingly, he hollers louder and repeats his sentence, only this time the dropouts increase. This problem is from over deviation. If a signal swings any farther than 4.5 Khz, our repeater's bandpass filter will chop off that part of the transmission, hence the dropouts. The weaker the signal is into the repeater receiver is more prone it is to chop somebody off. The filter is necessary to eliminate adjacent channel interference between repeaters.

    There is 2 ways to fix this problem, (1) Back off from the mike to limit the deviation. or (2) take the rig apart and set the deviation to less than 4.5 Khz. To adjust the deviation, a dev meter is needed. In most radios there are 2 audio adjustments, the first one is mike level, that will set the distance from the mike for you to speak. If you like to eat the mike then back this one way off. The second is the maximum deviation limit. This will limit the frequency excursions that your rig will take when it is modulated. Set the peak deviation for your rig for no more that 4.5 Khz.

    There are a lot of rigs out there that are not properly adjusted (or used).

    Sometimes you will hear a station that is badly distorted. The distortion doesn't seem to be related to how loud the guy is talking. This is usually caused by the person being 5Khz high or low from the repeater input frequency. If I hear this, I will usually tell the person to check his frequency dial to see if it is offset 5 Khz.

    There is another condition that can cause this, multipath. Multipath is a condition brought about by one or more reflections of your signal hitting the repeater antenna at slightly different times. This will cause phase distortion. This usually doesn't happen with strong signals. A strong direct signal will capture the receiver and any reflections will be over-ridden. If the incident signal is somewhat weak the reflections can cause multipath distortion. There isn't much that can be done to cure this problem except to get into a better position for accessing the repeater.

    Where are we?

    I have also heard comments about our repeater that was made due to a lack of understanding of the repeater sites. One of the comments were "yep, I'm at the summit of hwy. 17 going toward Santa Cruz and the 440 repeater sounds pretty bad. Maybe we should tell the club to fix the 440 machine."

    Needless to say, the person that made the comment doesn't have a clue where the repeater sites are, or that the 2 machines are on different mountains. Coverage South of Los Gatos on highway 17 is not too good for the 440 machine. Mountains block the path. The path isn't super good for 2 meters either.

    I'll give a quick rundown on the repeater sites. The machines that are located at Las Cumbres are (1) K6FB/R 2 meter machine, (2) K6FB/R 220 machine (3) K6FB AX25 Packet (4) K6FB TCP/IP Packet (5) W6SZS/R 1.2 Ghz machine. There is also a 420 link transmitter and receiver located at this site with antennas pointed toward Black Mountain. This site gives generally good coverage to the South, into Santa Cruz, Monterey, King City, etc. The North coverage is good except a line from Mountain View to San Francisco. This is due to a shadow from Black Mountain. Coverage is not good West of that line.

    We have coverage into the Sierras, Central Valley, etc.

    The K6FB equipment located on Black Mountain consists of (1) K6FB/R 440 machine and a 420 transmitter and receiver to link to Las Cumbres. The 440 repeater located there has very good coverage all over the Santa Clara Valley, San Francisco, Oakland, etc. There is coverage in the Central Valley, etc. This machine makes up for the lack of coverage of the 2-meter repeater.

    Also located at the Black Mountain site is the WW6HP/R HP ARA repeaters. The 2 meter repeater is on 147.315 Mhz + and the 440 repeater is on 442.00 Mhz + PL for both is 151.4 Hz. The coverage for those 2 machines is approximately the same as K6FB 440. Located at the same site are the BAMA repeaters, K6PRK/R, the frequency is 1284.950 -12 and 2424.850 -20. The PL is 88.5 Hz.

    Wait, there's more!

    Some other activities of the membership include a constellation of repeaters. The constellation consists of W6SZS/R 1284.850 -12 PL 88.5 (already mentioned above), K6PRK/R 1284.850 -12 PL 192.8 (low level in Saratoga), K6KMT 1284.850 -12 PL 100 (low level in Campbell). All of the repeaters are on the same frequency and respond to different PL's. All of the repeaters have coverage through the Santa Clara Valley and beyond. The W6SZS machine could be accessed near Oroville CA.

    For those interested in HF operations there is a SSB net on 3850 Khz daily except for Sundays from 0615 to 0730. The net consists of long-winded monologues reminiscent of 1950 ham radio operations. From the variety of topics, one must take notes! The largest group is on Saturday mornings. This net has been a tradition for more than 20 years.

    There is also a Sunday 160 Meter Nostalgia Net. The net meets on 1815 Khz at 1900. This net sets ham radio back about 40 years! The operation is STRICTLY old-fashioned AM.

    With all of these activities going full blast a ham radio operator is set aside from the common people, you can tell, just look for a house where all of the yard chores are un-done, five will get you ten, the person is a Ham Radio Operator.

    73 de Kilo 6 Poorly Radiating Kilowatt


    classifieds

    Wanted: Name of the Newsletter contributor that e-mailed me the article titled "First Repeaters?" and his Mindoro, Philippines experience. Please e-mail me with your name and call again (how embarrasing for the editor... he should be fired! --ed)

    We lost one of the Great Ones -- WA6TVN, SK

    by Jey KQ6DK

    I was recently saddened to learn of the passing of my friend Art Hoffman, WA6TVN. Long time listeners of the K6FB 2m and 440 repeaters will remember Art best for his advice on the Sunday night Antenna Forums and generally being available for questions of all sorts on most evenings.

    My first conversation with Art was on a Sunday evening Antenna Forum. It had taken a week to muster the courage to talk with Art -- I wasn't sure that he would answer my lowly questions regarding 6 meter propagation. I was already on my way to a Worked All Neighbors award.

    As it turned out I had nothing to fear. Art patiently explained a few changes to make to my second floor shack, to the cable, to the ground, and to the antenna support. He suggested building a copper pipe dipole and even helped me to make it tunable. Art always liked analogies to explain RF principles; it never ceased to amaze me when he would take something complex and boil it down to simplicity itself.

    Art took me under his wing two years or so ago and helped me to better understand the antennas that I used. He used a very practical approach; I learned by building not only at his house but at my own home. Sometimes we built one of something, but more often we built several of something. We built double skirted ground plane antennas. We built HT Dipole antennas. We ran antenna modelling software. I would usually have "homework" after each visit to his Carmel QTH and frequently after conversations over the air. He never forgot an assignment and would ask me how each assignment was coming along. I still have assignments to complete to this day!

    Some of the Las Cumbres members may remember the evening that I presented the double skirted ground plane, built it, and then used it to speak with Art at his home. I still have the plans for this antenna if anyone would like to build one. I will be building one for our new TCP/IP node and donating it to the club with an engraved memorial to one of our local legends.

    73 Art! I'll miss our visits.


    Thanks for the code practice

    Recently, Don Teixeira W6IQ requested time off from doing the Wednesday night code practices. The following letter was sent to Don.

    Don,

    Thank you for having been available for all of the past many Wednesday evenings to handle the Morse Code Practice time slot on K6FB repeaters.

    Recently one of our Las Cumbres members did a survey among our membership and found that the vast majority of our members are Technicians, without a foundation in Morse Code. Your weekly Morse Code nets have been instrumental in bringing that heritage to numerous hams within "earshot" of K6FB. I'm certain that many of the new and experienced hams have benefitted from your CW "Elmer-ing" these past many Wednesday evenings. Heck, even I, a mostly VHF guy, have been brushing up my rusty CW skills as time permits on your weekly nets.

    I'm certain that I speak for the members of Las Cumbres ARC, the board, and numerous hams in the area when I extend to you my heartfelt appreciation and thanks. I hope to be able to find someone willing to fill your shoes and time slot in the near future.

    I hope that our paths cross again, until then, 73!

    Jey Yelland
    President, Las Cumbres ARC


    Amateur Radio RF exposure rules to be effective Jan. 1, 1998

    Brad Wyatt K6WR

    The long-awaited FCC decision on RF Exposure rules for the amateur radio service were finally released in August. An excellent summary of the obligations the new rules places on individual hams is contained in October QST, pages 51 and 52. Two questions immediately will come to mind: when must individual hams be in compliance with the new regulations, and how must individual hams demonstrate such compliance. More details are provided in the QST article cited above, but in brief, here's the story.

    When - The new regulations become effective Jan. 1, 1998; however, there will be a transition period for compliance by individuals, as follows.

    1. New licensees after Jan. 1 1998 must be in compliance with the new regulations at the time for first licensing. The FCC is preparing a new version of Form 610, which will contain a statement to the effect that the new licensee understands and complies with the new regulations. That is, the applicant will certify compliance by the very act of signing off on the 610 application.

    2. All those licensed prior to Jan. 1, 1998, will have to be in compliance with the new RF-Exposure regulations whenever a Form 610 is filed, such as for a license renewal, upgrade, or other modification. Because the same revised Form 610 as used by new license applications is used for such modifications, the act of signing off on the 610 will certify compliance.

    3. All stations, new or old, must be in compliance with the new regulations no later than Sept. 1, 2000. This date must be met whether a Form 610 has been filed previously or not.

    How - The full story of how each ham must determine compliance to the new regulations is too lengthy to present here; additional details may be found in the Oct. 1997 QST article. Briefly, each ham, with some exceptions, will need to perform a routine station evaluation to ensure that maximum permissible power levels, as described in the new FCC rules, are not exceeded. Those running at or below certain threshold power levels will be exempt from routine evaluations, although they will not be exempt from complying with the RF exposure levels prescribed by the regulations. The full list of the threshold power levels is given in the Table below. For example, from 160 through 40 meters routine evaluations need not be performed at output levels of 500 watts PEP or less, while at 2 meters the level that triggers an evaluation is 50 watts PEP.

    Output PEP Thresholds for Routine Evaluation of Amateur Radio Stations

    Band (Wavelength)     Transmitter
                          Power (Watts)
          160 m               500
           75 m               500
           80 m               500
           40 m               500
           30 m               425
           20 m               225
           17 m               125
           15 m               100
           12 m                75
           10 m                50
       6-1.23 m                50
          70 cm                70
          33 cm               150
          23 cm               200
          13 cm and up        250
    

    Additional details on performing evaluations, as well as details regarding maximum permissible RF exposure levels are given in the FCC document OET-65, now available on the WWW. A supplement specialized to the Amateur Radio Service is being prepared by the FCC, but is not yet released. See the ARRL RF-safety Web page at http://www.arrl.org/ news/rfsafety, or at the FCC Web Site at http://www.fcc.gov/oet/dockets/et93-62/


    RF Guidelines program is available on the Web

    Looking for an on-line RF analysis tool? Well, then look no further. Next time you're on the Web, direct your browsers to the following site: http://www.cs.utexas.edu/users/kharker/rfsafety/

    The site is a WWW front end for a public domain C program written by Ken Harker KM5FA using the cgic library. This program has been derived directly from a public domain BASIC program written and published by Wayne Overbeck N6NB in the January, 1997 issue of CQ VHF, p. 33.

    It includes some good introductory comments, along with references to other relevant information.

    Check it out... it's worth the look.


    Ham radio: is it hazardous to your health?

    by Rick Zabrodski M.D.

    This manuscript was the basis for a talk given at the RAC Convention, 1994.

    Introduction:

    Over the past 10 years the general public has become increasingly concerned about electromagnetic fields (EMF) and their possible effects on the human body. Numerous articles in the press have linked electric power lines and other electrical equipment such as cellular phones to cancer in particular.

    After reviewing the available data, I conclude that, if EMF poses a health hazard for the ham radio hobbyist, the risk is relatively small. The effect on the typical ham radio operator is not likely to be a major problem. This is apparent when comparing EMF to the many well known, documented hazards that we face on a daily basis. However, EMF exposure does raise concerns; and further study together with "prudent avoidance," is advised. I will present a brief summary of what is currently known on this complex and rapidly expanding area of research. Then I will conclude with a rationale for appropriate, prudent behavior based on this knowledge.

    Definitions:

    To better understand the issues involved in EMF, we must first determine what aspects are relevant to the hobby of ham radio. EMF is usually divided into two categories, Ionizing and Non-Ionizing. Ionizing radiation involve frequencies from the ultraviolet spectrum and up. Examples include solar radiation, x-rays and radiation from nuclear explosions. The serious side-effects of ionizing radiation are well known and depend on frequency, intensity, and duration of exposure. This knowledge has led to specific public and occupational exposure standards (e.g. for x-ray technicians and employees of nuclear plants). Fortunately, your transmitter does not emit any ionizing radiation!

    The second category of EMF, more relevant to amateur radio, involves frequencies in the non-ionizing spectrum. This spectrum stretches from very low frequencies to the infrared region. Examples include EMF from power lines, transformers, and electric motors and radio frequencies stretching from VLF through microwaves. Non-ionizing EMF is further subdivided into thermal or athermal. That is, does the radiation heat tissue?

    The answer depends on wave-length and intensity. For example, we know that we can use relatively low-power microwaves to cook food and low-power infrared lasers to burn tissue in surgery. However, an individual situated near a high-power (megawatt) mf/hf/vhf antenna would experience biological heating (thermal effects). The ANSI (American National Standards Institute) guidelines have suggested limits for public and occupational exposure. These limits have been lowered repeatedly over the years, and they remain a topic of debate.

    Application to Ham Radio:

    In amateur radio we are usually concerned with lower-level radio frequencies that do not cause measurable heating to the body and are therefore classified as athermal. Currently there are no published scientific safety standards for power levels and frequencies that do not cause thermal effects. This is where most of the controversy begins! There is still not enough scientific evidence to establish what is going on here. Despite this we hear emotional statements from concerned citizens' groups and the equally polarized public-relations statements of profit-oriented multinational corporations.

    The potential consequences for various groups, including amateur radio, are tremendous. If a cause-and-effect case for a health hazard can be made, the cost implications will be enormous. If you think antenna restrictions are a problem, consider the problems of having to prove that you have an EMF-compliant radio station! (we're there --ed)

    A wide variety of scientific investigations from numerous sources have shown clear measurable biological effects secondary to athermal EMF. In describing these effects, the following hierarchy of biological levels is useful:

    • Free radicals
    • Cellular
    • Tissue
    • Organ system
    • Whole organism
    • Populations

    To complicate things even more, research at the level of cells and tissues suggests that other factors besides frequency and intensity are important. EMF modulation, bandwidth and timing characteristics have all been shown to have different effects. It is apparent that certain EMF "windows" may be more important than others.

    What are some of these effects? At the cellular level EMF causes measurable changes with calcium and hydrogen ions. There appear to be changes in cellular communications by way of electrochemical and enzyme pathways. These effects have been studied particularly in immune cell function (T-cells), as well as in cell growth and other types of cell recognition systems. At the level of tissues and organs, we now have evidence that the brain hormone melatonin is also affected.

    All the above are certainly interesting to biologists, but how do they affect you and me? The current literature suggests that EMF probably does not cause cancer. However, it may have a role as a promoter (enhancer) of cancer by modifying the cells in the immune system that normally act to prevent or correct cancer in its early stages. In other words, cancer cells may be created by a chemical agent or ionizing radiation. Subsequently the EMF-handicapped immune system may not be as effective in identifying and destroying these cells in time to prevent further cancer cell growth.

    At the other end of the hierarchy are the groups of organisms that we call populations. The study of diseases in populations is called Epidemiology. The often quoted epidemiological study, published in 1988, took as its "population" those amateurs on the 1984 FCC license file who had addresses in California or Washington State. After eliminating female names, the investigator matched 67,829 names against death records in the two states. From analyzing a substantial number of causes of death, he found that deaths from one form of leukemia and from cancer of other lymphatic tissue were higher than expected, by a statistically significant amount. Cancer of the pancreas accounted for significantly fewer deaths that expected.

    It is misleading, however, to place such emphasis on a few significant results that emerge from an extensive search. None of these were highly significant, and it would be reasonable to attribute them to chance. Importantly, about one-third of the amateur radio operators who died in Washington State had occupational electromagnetic exposure together with potentially significant exposure to solder fumes and toxic chemicals, including PCBs. This study and many others like it have not measured actual cumulative EMF exposure.

    They only reason that such exposures were likely to occur. What about the effects of EMF on female hams who live in Iowa? Often epidemiological studies give rise to more questions, rather than answers! Some subsequent epidemiological studies involving occupational exposures (generally much higher than hobby exposures) to EMF tend to support the atypical cancer findings initially described. These individuals were usually exposed to numerous other agents, and it appears that chemical exposure was particularly important.

    The "silent key" study provides no conclusive proof of a "cause and effect" relationship between EMF and cancer. Therefore, we now know that non-ionizing, athermal, low-level radiowaves used in amateur radio do cause biological changes in the human body that are measurable at the level of cells, tissues, and organ systems. The significance, if any, of these changes remains uncertain. It currently appears unlikely that they can be directly linked to causing cancer.

    Unfortunately, the possibility remains that they have a small but not yet clearly defined role in allowing other more toxic agents to cause cancer by promoting or enhancing their effects. Other effects may exist, both good and bad, that are yet to be described. I believe that, ultimately, this area of biological rather than epidemiological research will yield the definitive answers to our questions. At the same time we may also develop a better understanding of cancer and immunological diseases such as arthritis and AIDS.

    When we look at the scientific evidence at the level of the organisms and populations, the possible links between EMF and disease continue to be poorly understood. Nonetheless, the evidence raises concern, particularly in those individuals with significant exposure to EMF and other potential cancer-causing agents in their occupations. More study in this area is also indicated!

    Relative Risks and Prudent Avoidance

    Considering all this information, it would be wise to practice "prudent avoidance." As a ham-radio-physician, I offer this advice:

    • Don't smoke.
    • Don't get fat.
    • Eat sensibly.
    • Exercise regularly.
    • Wear a seatbelt.
    • Wear a sunscreen in the sun.
    • Wear a bicycle helmet when riding your bicycle.
    • Climb your tower on sunny, windless days and use a proper climbing belt.

    Paying attention to the these issues will provide a clear, measurable, and significant benefit for your long-term health. Once you have considered this advice, what about ham radio and EMF?

    First, we must recognize that the ANSI guidelines apply THERMAL effects. Furthermore, they do not take into account the modulation-dependent interactions that seem to be important in athermal EMF research. In fact, there are no guidelines for ham-radio-type exposure to EMF at present. However, I certainly would agree with the following general principles:

    * QRP : Use the lowest possible power as conditions permit. This is particularly important at higher frequencies and in situations where the antenna is close to the operator. The use of UHF/VHF handhelds would ideally involve a separate microphone with the radio and antenna held above your head. If this is not possible, the handheld should be kept as vertical as possible, using low power and brief transmissions (leave the long winded-lectures to 75 metre AM).

    When operating HF at levels of 100 watts or less, beams should be kept at least 35 feet above the ground, and higher when using more power. On a typical suburban lot a vertical should be roof mounted (they usually work better up there in the clear anyway). Any indoor antennas should be restricted to QRP use only.

    * Your linear should placed as far away from your operating position as possible. It should be reserved for "true emergencies," such as working 3Y0PI on the last day of the DXpedition as a "new one" for the DXCC Honor Roll.

    * I would emphasize that special care is required when operating at microwave frequencies, as the chance of significant athermal and thermal exposure is much higher. Further, more detailed suggestions can be found in various sources, including the ARRL Handbook and the ARRL Antenna Book.

    In summary, we now know that non-ionizing, low-level, athermal EMF does cause measurable biological effects. The consequences of these findings are yet to be accurately assessed, but further information will be forthcoming. Those at highest potential risk are individuals who have prolonged occupational exposure to EMF and have additional exposure to other potentially toxic agents. Although further study is needed, it appears that the risk from exposure to EMF in ham radio remains low when compared to other established health risks. "Prudent avoidance" is recom- mended.

    I hope this encourages all of you to quit smoking, eat smart and exercise safely. These measures, together with prudent QRP operation and high antennas, should allow us all to discuss this topic again for many years to come!

    About the author:

    Dr. Rick Zabrodski has been a licensed ham since 1971. He is in private practice as a family physician and occupational health advisor to various corporate and government clients. He has dabbled in almost every aspect of ham radio over the years, but his current interests are QRP contesting, building QRP equipment and occasionally chasing DX. He has a special interest in aviation medicine and is a pilot with a preference for "silent flight" over the Canadian Rockies. VE6GK (Glider King) lives in Calgary, Alberta, Canada with his wife Rhonda and two children, Sarah and Adam, who plan to become hams in the near future. He can be reached at: zabrodsk@med.ucalgary.ca

    Acknowledgments:

    The author wishes to thank Stuart Cowan, W2LX and Dr. Ross Adey, K6UI, who both who were very helpful in providing access to the current literature and made the research much easier. Thanks to all the scientific hams and non hams who provided input via the Internet. A special thanks to Dave Hoaglin, K8JLF, who helped with the preparation of this manuscript.


    Newsletter again?

    by Jim KN6PE

    As we head torwards Thanksgiving and the Winter Holidays, the rate that the days are passing seems to be getting faster.

    Why, I can remember sitting in front of my PC around the end of September thinking about the October edition of the newsletter. Before I knew it, October was half over, and I was heading fast into November. Ok, who turned up the clock speed?

    It's not that I haven't been enjoying Ham Radio; my tcp/ip project has kept me going (but that's another story); and some of the Shack work parties have been just that (!). Then, there's that day job that I must contend with.

    So, its is with almost disbelief that I'm find myself here again looking at the November deadline (now planned for the weekend of 11/7) and have to put this edition to bed. Soon enough, getting The Summit Sentinel out will be competing with Christmas shopping, family and friends, and parties... all the things that makes this time of year personally enjoyable.

    But I enjoy writing the newsletter as well. Which gets back to the issue of time racing by: Obviously, there's too much to do, see, and experience. While I'm compelled to slow down and take it all in, I find the things previosuly gone unnoticed not draw me in to take a closer look. Before I know it, I'm out of time... again!

    So, for the next few hours, I commit to stay focused on getting the Newsletter out the door. However, I may be back to negotiatee next month's edition!


    classifieds

    Wanted: Code Practice coordinator. Anyone know anyone who would be interested in filling this slot? I'd prefer that we have two or more willing to share responsibilities. Would be willing to share responsibilities one or two times a month. If interested, contact Jey KQ6DK.

    Remarks by Willie Brown, Mayor

    As reported by Tom K6KMT

    To: Emergency Communications Units - Information Bulletin
    To: Emergency Management Agencies via Internet and Radio
    By: Auxiliary Communications Service (ACS) of the California Governor's Office of Emergency Services
    EMC098 ACS & the Mayor of SF For release 9/22/98
    CITY & COUNTY OF SAN FRANCISCO
    DISASTER COUNCIL MEETING
    April 22, 1997

    Remarks by Willie Brown, Mayor:

    "...I must also tell you that I have been frankly fascinated with that unpaid group of people with those ham radios, the Auxiliary Communications Service. Now they are maybe the most active of all the volunteers. They are virtually over at the office every time I go over there. And I suspect that they hang out there. Now they're an interested group of people.

    "It is a communication system though, that I think now covers practically every community in San Francisco, and in some cases damn near every block in San Francisco, for emergency communication purposes, which means that a wireless system that seldom if ever can be totally disrupted by a disaster is within our grasp, and we are able to use.

    "Obviously the cell phones play a role in that now, but the ham radio operators are the heart and the soul and the life blood of that system. And so we do have a system that is virtually communications disruptive proof in terms of being able to do the communications that we may need to do.

    "There is also, I think, a level of training enjoyed by these people to carry out their task, and some method to identify them visibly in case of a disaster when they go into their operations mode."

    -----

    The above was submitted to the ACS Newsletter by Peter Dunckel, from the City & County of San Francisco OES ACS.

    The ACS newsletter is sent to those who indicate an interest in emergency communications by the way they respond to the ACS Web page (see below). In the issue in which the above was published, the following also appeared:

    "One of the biggest concerns we have is the ability for the government to recognize the efforts of the local volunteer community BEFORE the emergency takes place. I think it's pretty safe to say that the San Francisco ACS IS recognized. Our compliments to San Francisco for a job well done!

    Dave Larton, Training Officer (larton@garlic.com) Auxiliary Communications Service, Information Technology Branch Governor's Office of Emergency Services"

    ACS Web page: http://acs.oes.ca.gov

    FTP archive: ftp.ucsd.edu/hamradio/packet/tcpip/incoming for new bulletins and ftp.ucsd.edu/hamradio/races for earlier ones. OES ACS staff manager Stan Harter :Stanly_Harter@oes.ca.gov State Chief ACS Officer Cary_Mangum@oes.ca.gov

    EOM EMC098


    Highlights from the ARRL Pacific Division Update -- November 1997

    Brad Wyatt K6WR, Director, Pacific Division, ARRL
    (408) 395-2501 (Phone and FAX)
    Packet: K6WR@N0ARY.#NCA.CA
    Internet: K6WR@arrl.org
    WWW Pacific Division Home Page --
    http://www.pdarrl.org/

    Pacificon'97 Was a Great Success!

    From all reports, the attendees, speakers, exhibitors and vendors all had a great time. Thanks to Greg Estep, KE6VTA, and Sylvia White, KC6YJV, who were the Co-Chairs of the event. They and their crew put on the best show in the series so far. Now, on to Pacificon'98 at the Sheraton in Concord.

    KI6DS, WA6GER Pacific Division 1997 Hams of the Year

    Doug Hendricks, KI6DS, and Jim Cates, WA6GER, were named Pacific Division Hams of the Year for 1997 at Pacificon'97.

    Jim and Doug are the co-founders of the Northern California QRP Club, a.k.a. NorCal QRP Club. Both thought that the club would attract only a handful of radio amateurs in the Northern California area when they formed it in 1993. Due to their co-leadership and team efforts they now have over 2500 members in all fifty states and some sixty countries. It continues to grow at a high rate.

    Congratulations, Doug and Jim!

    10 Year Old Passes Extra Class Exam at Pacificon

    Joseph Simon III, KF6ACO, of Alamo, CA, originally licensed about one year ago, passed his Extra Class exam at Pacificon and was awarded his Extra Class license by the FCC the day before his 11th birthday. Congratulations, Joseph! Thanks to ARRL VEC and others.

    Latest Band Threat News

    This month (November) WRC 97 opens in Geneva. A great effort by ARRL and IARU has been put forth to protect our spectrum. We will not know the results of this enormous amount of work until the gavel comes down in Geneva on Nov. 21. For the latest detailed information, read "It Seems to Us" an editorial by Dave Sumner, K1ZZ, in Nov. QST page 9.

    Northern California ARES HF Net Established

    The Northern California ARES HF Net meets on the second and fourth Thursday of each month at 8:30 PM on 3987 kHz. Net control is the Siskiyou EC, Dave KC6HOY, who established the net. All EC's and ARES members in Northern CA are encouraged to check in. Southern Oregon stations also participate at times.

    The Sacramento Valley Section ARES now has a web page. It can be found at http://www.eheart.com/ares/

    Thanks, Jerry Boyd, K6BZ -- Pacific Div. AD, PSAC Rep. and SV SEC.

    Bob Schmieder, KK6EK, Wins Cover Plaque Award

    Pacific Division member Robert W. Schmieder, KK6EK, won the September 1997 QST Cover Plaque for his article, "The 1997 VK0IR Heard Island Expedition." Congratulations, Bob! This is Bob's second Cover Plaque Award.

    ARRL Audio News Debuted October 17

    The League inaugurated ARRL Audio News, a weekly, Web-based audio news service, on October 17. Compiled from the ARRL Letter, ARRL Audio News will include the week's top news from the world of Amateur Radio and the League. ARRL Audio News will be available in RealAudio format via the ARRLWeb, /http://www.arrl.org/. Tucson Amateur Packet Radio (TAPR) has generously agreed to provide space on its Web server to permit the League to offer this service.

    Each edition of ARRL Audio News will contain up to 10 minutes of timely Amateur Radio news. It will be available via the ARRLWeb every Friday by 9 PM Eastern Time. Dial-up telephone access will be announced later.

    For more information, contact Rick Lindquist, N1RL, e-mail n1rl@arrl.org; telephone 860-594-0222. Thanks, ARRL Letter Oct. 10, 1997

    State Department Applies for U. S. CEPT Participation

    The State Department has applied for US participation in the European Conference of Postal and Telecommunications Administrations (CEPT) Amateur Radio licensing system. The move, taken on September 22, could eventually make it easier for US hams to operate temporarily in European countries that participate in CEPT, without having to apply for a reciprocal license.

    Last fall, the FCC proposed amending the Amateur Radio rules to make it easier for hams holding a CEPT license or an International Amateur Radio Permit (IARP) to operate during short visits to the US. Thanks, ARRL Letter Oct. 10, 1997


    Las Cumbres Amateur Radio Club (LCARC)

    LCARC is a California non-profit mutual benefit corporation dedicated to Amateur Radio Service and Emergency Communication. It's purpose is to support scientific investigation in radio engineering and emergency communication skills development for its members.
    Repeaters and Services operated by LCARC
    K6FB/R:  145.450 MHz, (-), PL=100, linked with
    K6FB/R:  442.575 MHz (+), PL=100
    K6FB/R:  223.880 MHz (-), PL=100
    K6FB-1 Digipeater:  145.050 MHz
    K6FB-2 Bulletin Board:  145.050 MHz
    K6FB-7  Node:  145.050 MHz
    

    Nets and Meetings

    • The LCARC Net is held every Monday evening at 7:30pm on the K6FB/R repeaters. Guests and visitors are welcome to check in. Volunteers for net control for the following week's net are solicited (and encouraged) at the end of each net.
    • General meetings are held at the Hewlett-Packard Cupertino Site, Oak Room, Building 48, located at Wolfe Road and Pruneridge Avenue (entrance on Pruneridge) at 7:30 PM, on the third Tuesday of every month unless otherwise noted (see page 1 for location, dates). Talk-in on K6FB/R.

    Officers and Board of Directors

    Jey Yelland / KQ6DK . . . . . . President
    Ken Carey / KN6CK   . . . . . . Vice President
    Harry Workman / K6JTC . . . . . Treasurer
    Ned Rice / KE6ZOZ . . . . . . . Membership
    Jim Oberhofer / KN6PE . . . . . Secretary
    Frank Butcher / W6SZS . . . . . TCC
    Tom Campbell / K6KMT  . . . . . Trustee
    Dick LaTondre / KB6GLX  . . . . Member at Large
    

    Summit Sentinel

    The Summit Sentinel is published monthly by the LCARC. Permission is granted to reprint from this publication with appropriate source credit. The deadline for submitting items is the second Friday following each general meeting. Send your contributions to Jim KN6PE at:
    packet: KN6PE@N0ARY or leave on K6FB-2
    internet: jimo@cup.hp.com
    fax: 408-447-0460; phone: 408-447-0837

    LCARC Home