Speakers at our
Club Meetings

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.

Coming Up:
November 17, 2017: AMSAT and Satellite Operation, by Tom Deeble, KA6SIP.
December 15, 2017: No meeting. Replaced by the Banquet.

Past Presentations:

To review our speakers prior to this year, see our Speakers-2015 & 2016 page.

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

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 presentation 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.

December 16, 2016:
No meeting! Happy Holidays!

December 2
, 2016
MDARC Holiday Banquet
    Zio Fraedo's Restaurant in Pleasant Hill. See our Holiday Banquet page for details.

November 18, 2016:

Here's the MDARC DATV Experience that's Waiting for You

Eoin O'Donoghue, KK6Q

Trace my experience with MDARC (Amateur Television) ATV from the last millennium thru to today. Learn all about how you can get aboard for almost nothing and if you wish, graduate to the full MDARC (Digital Amateur Television) DATV experience. See various DATV station setups and there will be a demo of a functioning DATV station.

October 14, 2016:
Ham Radio Quiz Show!
at Pacificon

As panelists, we'll have Bob Heil, Gordo West, and John Bigley (ARRL Nevada Section Manager) answering questions from our moderator and the audience. Come on over and see if you can stump the experts. It's going to be a lot of fun.

Note this is a week earlier than our usual meeting date; the second Friday, since we're having it at Pacificon.

September 16, 2016:

Misa Siemons, KJ6BUE

A rundown on all the exciting programs and events scheduled for PACIFICON, this year’s ARRL Pacific Division Convention in San Ramon presented by our club’s hardworking volunteers.

August 19, 2016:
fldigi/flmsg … A Way to Quickly Move Message Traffic in Emergencies

Klaus Berkner, KK6KHB;
(with Djovida KJ6DJ and Dave Piersall N6ORB)

We Hams like to pride ourselves as being communication backups during major disasters.  But are we really prepared to move large amounts of traffic when called upon?  

Verbal transmissions are tedious and time consuming; however,  fldigi and flmsg are two free applications that make it easy for anyone with a computer or laptop to transmit messages quickly and accurately.  I will briefly contrast the two modes of communication and present an overview of the fldigi/flmsg capabilities. 

To download  fldigi/flmsg go to: https://sourceforge.net/projects/fldigi/files/

For set-up guidance go to: https://www.youtube.com/watch?v=bN2QPZZzkn4&feature=youtu.be

Here is the link to Klaus' excellent presentation: What is fldigi and Why Should We Be Interested? (PDF; 819 KB)

July 15, 2016:
Emergency Operations with the VA

George Hughes, W0WEB
Veteran's Administration, San Francisco

How the Emergency Response Management Team supports the VA during an emergency. Also will be discussing the process used to deploy our assets to support the local community as well other groups and agency's during an emergency. The discussion will conclude on how we work closely with the SFRC (San Francisco Radio Club) to provide communications and tech support using our satellite system which handles 6 phone lines, a two way video conferencing system and full Internet connection, as well as complete HIPA compliance work station. Each work station will have one or two radios. VHF,  UHF, H/F and soon Public Safety Radios for local Police and Fire depts. I'll also be bringing our Communications Truck to show off!

June 17, 2016
D-Star Advances & Updates

Jim Moen, KI6JM

Presenting new features with D-Star with a focus on improvements  in 3rd party hardware and software and multi-mode hardware and software.  The 3rd party software improvements will support DMR, D-Star and Yaesu Fusion radios.  Examples are DV4mini, DVMEGA and MMDVM. In some cases, there are opportunities for inter-operation between digital systems. This is a time of fast growth in amateur radio digital voice. 

May 20, 2016
Coax Versus Coax

Steve Lampen
Belden Cable

There are hundreds of different coaxial cables to choose from.  Even when we concentrate on just 75 ohm versions, there is still a dizzying selection.  Why are there so many?  How are they different?  What are their advantages and disadvantages in performance, ruggedness, life, cost?  Even shielding options, and shield effectiveness (transfer impedance), is a major issue. This presentation covers all of this and more including low and high-frequency applications, and the performance of connectors.

April 15, 2016
Annual Auction! No regular meeting.

Mar. 18, 2016
Tropospheric Ducting

Gordon West, WB6NOA, via Skype!
Annual Pacificon presenter;
Host of the weekly Ham Nation video podcast;
Nation-wide ham radio educator;
Author of numerous ham radio books;
All-around relentless promoter of amateur radio.

Gordon West explains , with visuals and live audio, why radio signals on 2 meters and on UHF travel well beyond line of sight during summer months.

Listen to hams regularly chatting SIMPLEX from the Santa Cruz mountains down to Southern California on 2-meters and 440 MHz . No linking nor repeaters needed. No satellites - just some hot air!

Imagine hearing a 2-meter signal from HAWAII, 2,500 miles away, coming in for DAYS during July! No linking, no satellites, all from HOT air! (hams are good at that!)

This will be a fun evening of range extension tropo ducting, explained by Gordon West, WB6NOA, coming to MDARC via Skype, this Friday night! Hear some radio signals that you will find hard to believe. 

....thanks to some HOT AIR! ......

Gordon has been a ham for nearly 50 years and holds the top Extra Class license. He also holds the highest FCC commercial radiotelephone operator license, the First Class General Radiotelephone Certificate with Radar Endorsement.  Gordon is a Fellow Member of the Radio Club of America.

Starting in the late 1950s "Gordo," as he is known, worked for some of the big names in the field helping to develop several innovative pieces of equipment. In the 1980s Gordon and his wife Suzy, N6GLF, began teaching ham radio classes at college and marine venues and authored Amateur Radio training books sold by Radio Shack and equipment dealers around the country. Gordon remains active from 75 meters through 10 GHz, spending at least a couple hours on the air every day, helping new hams make friends on the many nets he runs.
In addition, Gordon volunteers with the American Red Cross communications team in Orange County , California, and regularly offers free kids' classes and classes for cities to support their Community Emergency Response Teams (CERT).

NOTE: We're meeting in the church Sanctuary this month, so park in the upper parking lot.

Feb. 19, 2016
The Russians are Coming! ~~ or, Suburban Radio Fun in the Cradle of Radio

Bart Lee, K6VK
Counsel Emeritus; Historical Archivist
California Historical Radio Society

The presentation will talk about some recent work by the California Historical Radio Society VLF Interest Group: 

1) An introduction: Amateur Radio involving Russia in terms of East Bay contacts, and contests.

2) The history of radio from Popov and Marconi through Long Wave ("The Cradle of Radio") and transatlantic circuits (e.g., SAQ & RCA Radio Central) and transpacific circuits (e.g., KPH / KET in Bolinas, California),  

3) Amateur Radio and the Short waves.

4) The Death and the Resurrection of Long Wave Radio, from Russian and US & NATO submarines at VLF, through Navigation Aids, and to the new Long Wave ham frequencies.

Note: We're swapping our agenda this month. The speaker will address us first, at 7:30pm, followed by the business meeting, rather than our usual other-way-around.

Jan. 15, 2016

Radio Communication at Interstellar Distances

photo of David G. Messerschmitt
David Messerschmitt, KK6KFQ

Emeritus Professor
UC Berkeley

Based on recent progress in locating exoplanets outside our solar system, it is estimated that about 20% of those stars similar to our sun harbor planets in the habitable zone, meaning they could conceivably harbor Earth-like life. That adds up to an estimated 20 billion such planets in the Milky Way galaxy, and it is possible that a small fraction of those (but still an impressive number) harbor intelligent civilizations possessing advanced radio technology. It is appropriate to begin pondering how we might communicate information by radio with any extraterrestrial civilizations that might exist out there, and also with spacecraft (called starships) that we might launch toward nearby stars. In this talk we discuss the major technical obstacles to such radio communication, such as great distances, the cosmic microwave background, an ionized interstellar medium, and (for starships) relativistic speeds. We will also predict the character of digital modes appropriate for interstellar communication. Come and pay attention, because this topic may may appear in future ham licensing exams!

Nov. 20, 2015

CERT’s Assistance in the Search for a Missing Person on July 12, 2015

Nick Zubel,KK6VDF
Emergency Preparedness Coordinator
City of Walnut Creek

The process and protocol followed to mobilize CERT’s assistance in the search for a 74-year old woman with dementia and health problems on July 12, 2015.