Transmission Lines, Smith Charts, and Matching

Summary:

There are times in every radio amateur's life when a working knowledge of transmission lines and matching techniques is indispensable. Yet, this subject remains a mystery to many hams because of its mathematical nature. The Smith chart offers a means to understand and appreciate the beauty of transmission line theory without mathematics. Moreover, the design of matching networks using stubs and lumped elements can be formulated as a board game in which different kinds of "men" make different moves. This makes it possible to enjoy a quiet evening of quality time with one's significant other, playing a board game that, by good fortune, yields the design for a triple stub matching network for your 40 meter antenna. Steve will use an antenna analyzer to show how to analyze an antenna and design a matching network on the Smith Chart. Line losses will be explained, and some common myths about VSWR will be dispelled.

Speaker:

Steve Stearns, KF6OIK, got his start in electronics when his father gave him a Heathkit short-wave receiver as a Christmas present in 1964. He quickly got his novice ticket and built more Heathkits. He advanced to a commercial 1st class radiotelephone license and took a thirty year leave of absence from amateur radio, during which time he obtained degrees in electrical engineering from Cal State University, USC, and Stanford. Today, Steve works as Chief Technologist for TRW Firestorm Wireless Communication Products in Sunnyvale. He leads a group that develops advanced signal processing technology to improve radio reception by mitigating or eliminating cochannel and adjacent channel interference. Steve's technology is being applied in UHF mobile and cellular communication systems. 

It looks like there will be an antenna party again this year. Andy AC6GN has agreed to head this up on May 15th. See page 5 for details.

It has been almost a year and Field Day is upon us again. Mark your calendars now for the weekend of June 25 - 27. You might as well mark the third Friday, the 18^th, for the club meeting at the same time.

Livermore Swap Meet - 1st Sunday of each month at Las Positas College in Livermore, 7:00 AM to noon, all year. Talk in 147.045 from the west, 145.35 from the east. Contact Noel Anklam, KC6QZK, (510) 447-3857 eves.

Foothill Flea Market - 2nd Saturday of each month from March to October at Foothill College, Los Altos Hills. FARS NET on 145.23 repeater Thursday nights at 8 PM.
 
 

President: Jack Eddy WA6YJR
Treasurer: Shel Edelman, N6RD
Secretary: Martin Liberman, KD6WJW
Training Officer: Paul Zander AA6PZ
Radio Officer: Mikel Lechner KN6QI
Newsletter: David Wilkes KD6WRG

Board members: Dirk Thiele KE6ZUY, Dick Baldwinson N6ATD; Hans Neumann KE6TGA; Martin Libeman KD6WJW; Herb KF6BKL; Howard Califf KE6PWH, Arv Hamer WA6UUT; Larry Moore KM6IU.

K6YA Station Trustee: Stan Kuhl, K6MA

FARS Web Page: www.fars.k6ya.org

FARS announcement mailing list is moderated, so you cannot reply directly to the list. To subscribe, send the word "subscribe" to: emarc-request@ham.yak.net; For help, send the word "help" to majordomo@ham.yak.net; For human assistance, email to: human@ham.yak.net.

The FARS Relay is the official monthly newsletter of the Foothills Amateur Radio Society Meetings are held at 7 PM on the fourth Friday of each month except January (Winter Banquet); and 3rd Friday in June, Nov. & Dec. Annual membership $20; family $25. Visitors are always welcome! Directions on the back page. Talk-in: W6APZ (145.23-, 100Hz) or W6ASH repeater (145.27 or 224.36). Contributions to the newsletter from members, family, and guests are earnestly solicited! Contributions subject to editing and/or compression. ASCII files via packet, Internet or diskettes preferred; but all readable forms welcome. Here are the various ways to reach the editor:

Packet: KD6WRG@N0ARY.#NOCAL.CA
Internet: dwilkes@svpal.org, davewilkes@aol.com

VHF voice: KD6WRG on W6APZ, 145.23- (100Hz PL) FARS net Thursdays 8 PM; Various other times. Mail: 1093 Kelly Drive San Jose CA 95129-3222 Voice: 408-996-1613 (Until 9 PM); Fax: 408-725-1036
Eyeball: at FARS meetings.
 

I have been reading the back issues of the relay back to the beginning of EMARC and I will be compiling the history of EMARC/FARS. I will include with the relay each month some of the interesting things.

The first relay was put out in March of 1973. The members nominated for officers at the second meeting were President Fred Barry K6RTU, Vice President Fred Canham K6YT, Secretary Jack Eddy WA6YJR, Treasurer Sy Stein WA6ROM, Radio officer Ross Forbes WB6GFT, Activities Manager Jerry Starkey WA6LIJ and the board of directors were Bill Itel W6VF, Bob Smithwick W6JZU, and Thorn Mayes W6AX. These were the Hams that guided

the club through the first year which was very successful.

It is time for everyone to get into the spirit of field day and I hope each of you will find some time to help out. We are in need of someone to head up the committee for the picnic on Saturday night.

My thanks to those of you who are always ready to lend a hand.

Special thanks and "well-done!" are due Hans Neumann, KE6TGA, for fixing and improving the club station's CW paddle. The job was done up to Hans' usual very high standards of workmanship.

Silicon Valley Public Access Link, a non-profit organization, is shifting its emphasis to service non-profit organizations in addition to individual accounts. Non-profits can have a low cost Internet presence, email discussion groups, and can save money by sending out their newsletters by email. For all accounts, SV-PAL now has graphical browser capability available. As a subscriber to SV-PAL myself, I want to tell you it is a pleasure to have a home page without all those damn ads popping up all the time. See me or Dennis Paull for details.

Andy VE3FZK passed along the following from Dennis Freeman K6YLN.

Freeman, Dennis wrote: I notice on the S.H.A.R.K.K. www.sharkk.com list a large number of repeaters at 51.82 have been recently added. Are these linked? Is there some group or club a person could join to help keep these repeaters going? Is there some general purpose in mind for these repeaters? They are listed as open, seems as though someone has gone to a lot of expense and a lot of work.

I have a licensed friend with licensed children in college in Santa Barbara who would like to be able to communicate with them. If these repeaters are all linked, will that mean the friend will be able to do this?

I live near Pescadero, California, (between Santa Cruz and San Francisco), I was able to hear the repeater(s) until I got about 10 miles south of Half Moon Bay. I was using a 5-watt ICOM T8A. Perhaps with a better antenna/more power, I could reach either Skyline, San Jose or Santa Cruz from home, but can't with the T8A and it's whip.
 
 

To: Freeman, Dennis

Subject: Re: 6 meter repeaters

The repeaters are not yet linked. This is our Y2K project. We have some of the link radios (15 of the 27 required) installed but have not done the final adjustments. The Bay Area sites will be linked first -followed by the Central Valley -and then Central Coast.

The ultimate configuration will be all receivers operating on 51.32 MHz and voting. The transmitters will operate on 4 different frequencies. This way, the users will simply transmit of 51.32, and select up to 4 receive frequencies. Ultimately, you'll just need 4 memories in your radio.

CERT is the "Communication Emergency Response Team". It is a group of hams whose charter is to provide emergency communication in cases where no other communication medium is available. All sites have emergency power (generators). There are no dues. Yes, I have gone to a lot of expense and work to make this happen. It was a project that I've wanted to do for a while. I had already built 4 UHF repeaters and 1 6 meter repeater and envisioned a multi-site 6 meter system since it hadn't been done on such a magnitude. I mostly listen. The benefit I get out of the project is providing a good, open 6 meter repeater system to the amateur community and having a network to develop. I can hardly wait to get the voting and linking system together. It is one big experiment!

The group was formed by me 3 years ago and consists mostly of GTE employees. GTE sponsors the site space, and Paul KD6EUJ and I built all 14 repeaters. The repeaters are modified GE MASTR II radios.

You will definitely need a better antenna than the portable antenna. You'll also notice that in-building penetration is poor. The benefit is better long-distance highway coverage (with a mobile) and not too much activity. 6 meters is definitely a challenge.

Your friends are welcome to use the repeaters. The one on Santa Ynez should cover Santa Barbara real well. The "Skyline" repeater is at Skylawn Cemetery. When they are linked (next year) they'll work well.

It had us worried, but our flea market on March 13 was a very good one. Although the rain held off and opened a window for us, the morning started out gray and cold, most of the sellers came in later than usual, and the usually eager, first-of-the-season crowd of buyers arrived in force later still. But all?s well that ends well, as the bard said, and this FARS market ended up very well indeed-among the best, possibly the best, of the seven markets I have run for the club. We sold exactly 150 spaces, a high figure and the most for us (and, I believe, the other clubs) since the 1997 season.

None of this would have been possible without the help of a number of fellow club members. I must explain, however, that buying the supplies is easy, getting a few people to help carry them to the market is maybe only just a little bit harder, and running the market on market day is straightforward enough. The really frustrating, difficult, and most worrisome part of running a market is that not many people sign up ahead of time for shift duty-so the market day chairman (me) is worried right into the market itself that there will be insufficient staffing to run the market. Please, everybody, next time, sign up in advance!

With that bit of grousing out of the way, I want to thank everybody who helped with supplies and showed up for work. Charlie KF6CUU Arney was of enormous help: the Red Cross van had been in an accident and was unavailable, so Charlie and his truck showed up Friday evening at the Palo Alto Red Cross to load and carry off the food-table "hardware," then showed up at 4:00 a.m. the next morning to help set up the market, then worked the entire market, then carted everything back to the Red Cross!

I thank you all very much, indeed. I think the list below shows everyone. If I missed someone, I regret it and do apologize.

Charlie KF6CUU Arney
Andy VE3FZK Korsak
Dick N6ATD Baldwinson
Martin KD6WJW Liberman
Floyd K6BSU Carter
Hans KE6TGA Neumann
Don W6VTK Conant
Ann KC6PUM Paull
Jack WA6YJR Eddy
Dennis KC6PUN Paull
Robert KE6TFU Flemate
Norm W6IQX Rehbein
Jeff KD6MNP Furman
Steve KQ6LX Whitt
Arv WA6UUT Hamer
Dave KD6WRG Wilkes
Andreas N6NU Junge
Paul AA6PZ Zander
...and the gatekeeper, Rick WB5VUL Joslin

In the end, of course-when it's all over and things have turned out well--, it's been a whole lot of (very tiring) fun. We'll do it all over again on April 8, 2000 (which, contrary to all the hype, is not in the next century; the 21^st century starts January 1, 2001 - sorry, I just had to say it).

Father Wenceslaus Knotek KC6JDI

Father Knotek died December 14,1998, at the Maryknoll Headquarters in Maryknoll, NY. "Wence", as he was known by his many friends, has been living in the local Maryknoll retirement facility in Los Altos. This is where the Foothill ARS has been operating on "Field Day" for many years. Before his retirement, Wence spent his working life as part of a Catholic Mission in the orient and, as part of his job, learned to speak Chinese fluently. He was in the orient during world war two and became a prisoner of war when the Japanese invaded that area. His group was not put in an interment camp but was allowed to live at the Mission with limited freedom. He had many interesting stories to tell of his experiences at that time. Wence was a very intelligent individual with an interest in electronics. One of his war stories told of discovering an early day tube type hearing aid left behind by a previous Mission worker and using the parts to build a short wave radio so he could get news from Voice of America. Wence came from a large family, he was one of ten children. One of his brothers was a ham, W9GKM in Racine, WI. After retirement and moving into the Maryknoll here, Wence got his ham license in order to be able to talk with his brother. They maintained regular schedules on 15 & 20 meter CW. In addition to his ham radio interests Wence other technical interests. He built and maintained a working seismograph at Maryknoll. He installed a sound system in the facility Chapel and, when he found that some hard of hearing retirees couldn't hear the service very well, he connected infra-red transmitters to the sound system and provided infa-red receivers with earphones to the hard of hearing. He also solved another problem, there was an elevator at Maryknoll that frequently became stuck on one floor because someone left without closing the door. Using parts from Radio Shack, he installed an automatic announcement system on the elevator which, after an appropriate time lapse, would announce in a loud clear voice "PLEASE CLOSE THE DOOR" and repeat this announcement until the door was closed. Wence will be sorely missed by all that knew him.

Amateur radio operation at the local Maryknoll facility has a fairly long history. There is a 60' four legged freestanding tower complete with a Telrex tri-band beam. The tower, visible from Hwy 280,~is located some distance from the main building. There is a small building adjacent to the tower with a small room at one end that serves as the "Ham Shack". We don't know when the tower was erected but we do know that about thirty years ago, one of the Maryknoll Fathers was a ham and was quite active. After he left there was no activity for several years and the antenna lost some of its elements in the winter storms. About fifteen years ago another ham, Brother Brian KA6FRK, retired, moved into the facility and needed help to get on the air. Jerry Starkey WA6LIJ SK-'88, organized a work party, the beam was removed, repaired, and replaced along with a new rotator, two meter vertical and new coax. This was not a simple task since someone (Fred Canham K6YT) had to manhandle the beam at the 60' level and the rest of us had to untangle the beam from the trees that had grown tall since the tower had been erected. It is not known if any of the present residents of Maryknoll have any plans to take over where Wence left off.

Antenna Test Party

Date: Sat. May 15, 1999

Place: Palo Altos Baylands Nature Center Parking Lot (tentative)

Time: 9:30am to 12:00pm

Food: Donuts will be provided for early birds (donation appreciated)

Drinks: Bring your own

Description:

Bring your Ham Antenna and see how well it measures up. An antenna range will be setup to test your 2M antenna for gain and directivity (if you have a directional antenna).

New this year will be a special handie-talkie emulator setup for testing HT antenna. Now is the time to bring all your rubber duckies out to see how well they swim (or sink).

We will also have equipment available to print SWR plot for your 2M, 220 and 440 antenna. Bring your home-brew J-pole, 1/4 wave, beam, vent-pipe or whatever if you need to do some fine tuning on your SWR and bring home the test results.

For more information please contact Andy Fu AC6GN at AC6GN@amsat.org or by phone at 408-813-1093

Thanks.

How to get to meetings:

(Visitors always welcome)

FARS meets at the Covington School District building, 201 Covington Road, Los Altos. Take the El Monte exit (The same exit as for the Foothill Fleamarket) off of I-280 and go East on El Monte. Cross Foothill Expressway and turn right at the next light on to Covington (Note Saint William church on corner). Stay to your left as the road forks. Just past the fork, turn left into the school parking lot. Walk through the center hallway and turn right. The meeting room is the first door on the left. Talk in on 145.23 or 145.27, negative offset, 100 PL.