Speakers at our
Club Meetings







July 20, 2018:
Building a Club Grade Repeater From the Junk Box

by Andy Record, KF6TJR

Andy's presentation will be on building a club grade repeater from the proverbial junkbox.  He will outline the Martinez Amature Radio Club's goals, repeater 101, the technical and legal requirements of a repeater and the ups and downs of building one.  Join Andy as he takes us through the "How hard can it be?" of building a repeater!

Andy Record will be a licensed Amateur for 20 years this September, and now self identifies as an OM.  He is a Project Manager for Silke Communications where he is overseeing and coordinating the City of Roseville's transition to an EF Johnson P25 Phase II system as well as several other smaller projects.  Silke Communications has the world's largest Kenwood NXDN system, stretching from the Canadian border to Bakersfield in Washington, Oregon and California.  His wife Tiffany (KG6TJR) and daughter Amelia (KK6VYZ) are both Technician Class Amateurs and they enjoy gardening, reading and their two cats.


Coming Up:
July 20, 2018:        Building a Club Grade Repeater From the Junk Box
                                           by Andy Record, KF6TJR
August 17, 2018:    The Victorian Internet: A History of the Telegraph
                                    by Larry Lauber
September 21, 2018San Ramon Fire's Response to the Sonoma County Wildfires
                                    by Brian Lindblom, WB6TJR
                                    by Edison Fong, WB6IQN
                                    At PACIFICON!!!
November 16, 2018: Story of Eight (8) Island on the Air (IOTA) Expeditions in Caribbean (YV)
                                    by Jignesh Desai, AD6TF
December 21, 2018No Meeting! Join us at the Holiday Banquet instead, Dec. 3.



Past Presentations:

To review our speakers not on this page, see our Speakers-2015 & 2016 page.


June 15, 2018
The World of Air Traffic Control
by Kurt McAninch

When we think of Air Traffic Control, first we think of "The Tower". This is only one part of a much larger picture. If we think deeper, we'll think about Radar. Radar is just one of the tools Air Traffic Control uses. There is Radar, Visual, and non-Radar. This triad is mirrored in another triad; the journey a flight makes from its departure location to its final destination. The first part of any flight is controlled by the Tower; the next step is the Approach Control; and the end route phase is controlled by "the Brickhouse".

Join us as Kurt takes us into the fascinating world of Air Traffic Control.

Kurt was born and raised in Iowa. He graduated in 1979 from Iowa State University with a degree in Fisheries and Wildlife Biology, and moved to Sacramento in August of 1980. The options for environmental jobs were few then, so he punted and answered an ad in the Sacramento Bee for Air Traffic Control. Receiving his training in Oklahoma City, he returned to California and served for 32 years as an Air Traffic controller. He controlled air traffic with radar and non-radar oceanic procedures. He moved to the ATC Procedures office and then into Air Traffic Flow Control. In 2007, he was assigned as a Military Operations Specialist, where he served until retirement.

The slides for Kurt's talk are available at:
https://drive.google.com/open?id=1ARToxSpUR1IYpvqnHJ_zGhAa-cLle_k8 (PowerPoint, 19 MB)



May 18, 2018:

Convolutional Encoding and WSPR: The New QRP
by Jamie Taylor, KK6OLF

Digital modes such as WSPR allow machine to machine communication over thousands of kilometers using extremely little power (often a watt or less.)  Though these signals are frequently buried in the noise floor, digital signal processing allows them to be perfectly decoded.

Software Defined Radios such as HackRF and open source tools like GNU Radio and IPython allow Amateurs to build customized transmitters and receivers, allowing them to experiment and explore these highly efficient protocols.

This talk will demonstrate how these tools can be used to learn more about Amateur modulation techniques, and why the class of protocols which includes WSPR, in particular, is so robust.


April 20, 2018
Annual Auction. See our Auction Page for details. No presentation this month.



March 16, 2018:

An Introduction to the Use of Free Software for the Design and Analysis of Amateur Radio Antennas
by Jim Blodgett, KI6JB

The Numerical Electromagnetic Code (NEC) is a computer program largely used for antenna analysis with a long history of development at Lawrence Livermore Laboratories with earlier work done at other locations.   Some versions such as MININEC, EZNEC and 4NEC2 are designed to run on PCs and are available to the public.  While these programs may be equally powerful, 4NEC2 is a completely free program that is downloadable from multiple internet sites.  It allows graphical entry of antenna structures and will analyze patterns, impedance, efficiency and other parameters.  This talk demonstrates the use of 4NEC2, both in real time and with examples of previously designed antennas.  This program is of use to anyone interested in designing or analyzing the types of antennas used in amateur radio such as monopoles, dipoles, Yagis, log-periodics and other antennas built primarily from wire or rod elements.  While the program is very powerful, no particular mathematical skill is required to use it and with a little bit of effort, fairly complex structures can be analyzed by the amateur.

Jim obtained his advanced class license in 1979 on the same day he obtained his first-class commercial radiotelephone license.  He was inactive as a ham until a couple years ago when he upgraded to extra class.  He now has a HF/VHF/UHF station at home as well as one with the same capability in his Jeep Wrangler.  Jim has been an employee of Bell Laboratories and their related spin-offs for most of the last 40 years.  He is currently employed by LGS Innovations where he is a Distinguished Member of Staff and the Chief RF Technologist.  Current work is the design of extremely wideband radios for various applications.  He has been granted 19 patents with one pending in the fields of communications, circuit design, system design and antenna design.
Jim is an ATP licensed pilot who occasionally terrorizes MDARC presidents in formation flights.

The slides for Jim's talk are available at:
https://drive.google.com/open?id=1W-ZZeG1t0dYsV0OImsRnQc2cLxUT6EEt (PDF, 15 MB)



February 16, 2018:

If the VIRGA obscures your CREPUSCULAR RAYS, hope for the PETRICHOR, and not the DERECHO!
by Ron Bunch, W4FEK

The February MDARC SkyWarn presentation consists of power point slides, mixed with short videos. A review of weather observing equipment (also on display) and methods, national organizations and how the weather affects such a wide variety of industrial, commercial and personal  activities.

My initial foray into amateur radio came via my paper route...but that was after my cousin Henry gave me a SX-38 shortwave receiver. I regularly listened to that very attractive woman on Radio Moscow and was fascinated that I could hear things from all over the world. One afternoon while returning from my route, I noticed a wire going across someone's back yard, I stopped and asked if a ham lived there...W4IND - Shirley welcomed me and took me up to see his rig. He loaned me an oscillator and a few months later I rode my bike downtown to the FCC office and took my Novice. First time passed the code and written test and a few weeks later I magically became  WN4FEK.

Then there was high school, those pesky girls and a week out of High School I found myself in the Marine Corps. I credit ham radio with keeping me sane and alive - I was placed in radio school and spent most of my time in MCAS Yuma, AZ - after 18 months in 'Electronics School'.

Then there is this thing called 'life'... Some time in college on the VA bill, and all manner of things. In the early 80's I found myself putting computer clones together for sale, then Token Ring networks which led to Ethernet installs.

I would not be here today, without ham radio....But what does this have to do with SkyWarn?


January 19, 2018:

Locating and Killing Receiver Interference

by Gary Johnson, NA6O

Anyone who operates in the HF bands knows that noise and interference are often your greatest challenge when it comes to hearing other stations. This talk will discuss various sources of interference, how to locate problems, and how to mitigate them. Methods presented here are also useful in cases where your transmitter is causing problems with other equipment.

Gary Johnson has been licensed since 1972 and primarily enjoys contesting, antenna design, and anything involving CW. He is an electronics engineer, recently retired after 35 years at Lawrence Livermore National Laboratory (LLNL). He has written two books and has nine patents. Besides ham radio, he also enjoys woodworking and metalworking.

The slides for Gary's talk are available at:
http://www.wb9jps.com/Gary_Johnson/Amateur_Radio_files/Finding_Noise_NA6O.pdf (PDF, 931 KB)


December 15, 2017:
No meeting in December.
Join us at the
MDARC Holiday Banquet on December 3. Register by Nov. 27th.


November 17, 2017:

Fun with the LEO Satellites – Operating Portable
by Tom Deeble, KA6SIP
With equipment that you may already have or with a minimal investment, you could be talking on the FM “EasySats” or to the International Space Station (ISS).  I’ll be going over some technical stuff about the satellites, radios, etc. but will mostly talk about the fun, and challenge, of operating portable in the field – from Tahoe in the winter, to the desert, to Hawaii, and lots of other locations.  There will be lots of pictures showing portable operation and also different radio setups.

To download Tom's slides, click this link: K6SIP AMSAT Presentation. (PowerPoint [pptx]; 42 MB)

Tom Deeble was originally licensed as a Novice while in Jr. High, around 1967, as WN6RJC.  He rowed light weight crew one year and graduated from UC Berkeley EECS in 1975.  He was also an engineering coop student working at China Lake NWS on the Sidewinder guidance.  He worked 35+ years for BART in Train Control Engineering and Computer Systems Engineering.

Two kids came along and that mostly curtailed Ham Radio.  In the 80’s he built a home-brew terminal unit and computer system based on a 6502 micro-processor based evaluation board connected to an ASCII terminal.  He passed his extra class exam (and 20 wpm code) just as the last of the 1x2 calls had been issued.  He also helped with CCRA’s VE exams.

At Pacificon he watched a video presentation by Randy Hall, K7AGE, which started his interest in satellites.  He realized that his old ICOM IC-W32A was a perfect dual-band radio for satellite use and then purchased an Arrow antenna at Pacificon.  He also operates from home with an elevation/azimuth rotor supporting dual yagis on a 25’ pole, with full computer control.

Other interests include bike riding – both mountain bikes and road bikes.  His main goal each July is to ride with his daughter in a 24-hour benefit bike ride in the Sierra Valley north of Truckee.  It’s a benefit ride for Christian Encounter Ministries in Grass Valley.  He averages somewhere between 150 to 232 miles in the 24 hours.


October 20, 2017:

At Pacificon! Making Maker Faires Work, by David Witkowski, W6DTW.
            See the Pacificon web site for details.
            Remember, this will be at Pacificon, the San Ramon Marriott hotel,
                not our usual meeting location.







September 15, 2017:

Pacificon Review

Misa Siemons, KJ6BUE, Pacificon Chair
Misa will update us on all the events and forums that will be at this year's Pacificon, this year’s ARRL Pacific Division Convention in San Ramon presented by our club’s hardworking volunteers.




August 18, 2017:
So Much More on W6CX-R


Trevor Hall, WA6JAU
Our own Trevor Hall will update us on the systems we have on Mt. Diablo's South Peak. He will explain how to access each of the repeaters; Echolink and IRLP connections; and show the programming of D-Star and how access works.




July 21, 2017:
From Crystal Sets to WiGig- Spectrum Analysis, the RF Engineer's Basic Tool


by Rob Rowlands, NZ6J

Rob Rowlands is a semi retired electrical engineer from New Zealand. The first part of his career was with New Zealand telecom, and since 1989 with Hewlett-Packard and its descendants in the SF Bay Area. Rob has a degree in electrical engineering from the university of Canterbury in Christchurch NZ and is a life member of the IEEE.

Rob has been licensed since 1963 and is interested in Mountain top operating, APRS and public service events.




June 16, 2017:

Magic-1, A Completely Self-Designed and Home-Built Minicomputer


by
Bill Buzbee

Constructed from more than 200 74-series TTL chips and roughly 4,000 individually wrapped wires, Magic-1 doesn't use a standard off-the-shelf CPU, but rather the bulk of the machine is itself a custom-designed CPU with its own unique instruction set.

The talk will include a demonstration of Magic-1, but will primarily focus on how it all came together.  In particular, how Bill's oddball kitchen-table hobby project became a collaborative effort involving computer and electronic hobbyists from around the world.  The machine has been connected to the internet for more than a decade offering open telnet access to thousands of curious visitors, and serving web pages at http://www.magic-1.org.  It's been the subject of "Slash-dottings", several magazine features, "Editor's Choice" award at the Maker Faire, and multiple awards at vintage computer festivals.  More information about the project can be found at http://www.homebrewcpu.com

Bill Buzbee is currently a Senior Staff Software Engineer at Google in Mountain View, CA, where he works on the runtime system for Android.  He previously worked at Hewlett-Packard Laboratories, the Transmeta Corporation and Hewlett-Packard's compiler lab.  He holds 31 patents, mostly related to dynamic translation and just-in-time compilation techniques.  In a previous career, Bill was a newspaper journalist working at small daily papers in the Midwest - including a stint as the managing editor of the Parsons (KS) Sun.  He lives in Half Moon Bay, CA with his wife Monica, three kids and a very energetic Australian Shepherd dog.



May 19, 2017:

Easy Up, Easy Down, Easy with HOA

by Dave Piersall, N6ORB
How to work the world with temporary antennas in an HOA. Space and time permitting, Dave will demonstrate a LNR 20 meter end-fed wire antenna and a 10 meter horizontal loop antenna with a mast and tripod made from military mast sections.


April 21, 2017:
Annual Auction! See our Auction page.


March 17, 2017:
Hospital Communications: Planning Required

Duane and Melanie Mariotti, WB9RER & KC7VFT
This presentation
will be on the unique world of hospital emergency communications and the amateur radio perspective. It will focus on the success in Northern California of the Bay Area Hospital Network (BAHN), lessons learned statewide as well as changes seen nationally.  (Duane coordinates a management group of hospital communications leaders across the US.)  The goal is to provide planning suggestions to build on the foundation and success of BAHN in the 21st Century.  This presentation is not simply amateur radio focused and may be of value to local hospital emergency planners as well as governmental emergency preparedness professionals.  MDARC is welcome to invite others to this presentation in the spirit of emergency communications planning.

Duane Mariotti, WB9RER
Duane Mariotti, WB9RER, has been licensed for over thirty years.  His primary emphasis is emergency communications and specifically hospital communications.  Duane's experience as a paramedic, emergency preparedness liaison and hospital biomedical engineer provided him with knowledge of both the amateur and hospital needs for communications to function.  Immediately post 9/11 he was assigned to support the Washington State EMS communications planning and implementation (in addition to his day job).  He has been a frequently requested speaker, committee member and consultant regarding hospital and health communications regionally and nationally. 

Duane is currently the Coordinator of the Kaiser Permanente Amateur Radio Network (KPARN) in Southern California supporting 20 facilities spread out over six counties (about the size of Indiana).  KPARN provides consultation, membership training, hospital standardized communications technology and infrastructure to support "conference call" emergency communications - specifically post the much discussed due earthquake.

Melanie Mariotti, KC7VFT
First licensed at the age of nine, Melanie KC7VFT moved locally six months ago after passing the California Bar Exam.  She is employed locally practicing environmental law. Melanie brings a lifetime of emergency communication practice and knowledge - specifically hospital communications - based on being her dad's travel companion.  Some of Melanie's earliest memories was participating in an EOC radio drill - standing on a table - to write on a white board important information.  She was eleven.

NOTE: Our March meeting will be held in the Church Sanctuary, on the upper level. Be sure to park in the upper parking lot for the March meeting only.


February 17, 2017:

So You Got a DMR Radio, Now What!

Tim Barrett, K6BIV
Tim will discuss the how and why of programming your DMR radio to operate with the BrandMeister Network.
(What Tim says he looks like. Courtesy K6BIV)------>

Tim Barrett, K6BIV is the Trustee of the VHF K6MDD DMR Repeater on Mt. Diablo. Tim is also the Trustee of the UHF K6PIT DMR Repeater in downtown Pittsburg, CA.

Tim is a Founding Member of NorCal DMR, a Network of more than 50 VHF & UHF DMR repeaters covering most of Northern California. This Network is connected to the BrandMeister Worldwide Network of more than 1100 DMR Repeater and Hotspots.

Tim Barrett, K6BIV, has been a Ham since 1975.  He has been active in repeater building since 1977. He has been a member of MDARC since 1979, a member and a former Director of NARCC, and the current Director of Spectrum Management at NCDCC (Northern California Digital Coordination Council). Tim has been involved in digital modes for a long time.  He was a pioneer in Packet (Digital) radio and has been active in Digital Modes for more than 32 years. He is the owner of IRLP Node 3348 and EchoIRLP Node 62684, which he runs mobile.
(What WikiLeaks says Tim looks like. )------>
Tim's PowerPoint Presentation, "Digital Mobile Radio - Code Plug 101" (PPT, 354 KB)


February 17, 2017:
System Fusion Demonstration
Unfortunately, Chris Wilson is no longer with Yaesu and was unavailable for this presentation. We hope to have it at a later date with another person.

January 20, 2017:

Antenna Basic Principles

Michelle Paquette, AA6MP
A one hour rundown on what makes an antenna actually work, from physics to practice.  We will look at how an electric field produces a radio wave, basic dipoles, and how a dipole radiates.  We will look at the effect of other conductors near the antenna, and discover some interesting interactions.