Introduction to HF Digital Modes – WEFAX

Most of the time we at the SCMA tend to focus on VHF and UHF communications, but have you always wondered what other types of radio communications there are? Well, the next few articles I write will cover High Frequency (HF) communications. The HF band covers radio frequencies from 3 to 30 MHz. This portion of the spectrum is just below the VHF band and just above the Medium Frequency Band (MF). You may have also heard the HF band referred to as the Shortwave Band.

This artile will focus on a mode of communications called Weather Fax (WEFAX). The National Oceanic and Atmospheric Administration along with the US Coast Guard provides a service which transmits weather maps via HF frequencies to mariners at sea.

One of the many WEFAX images I downloaded.

One of the many WEFAX images I downloaded.

Although ships these days are usually equipped with satellite communications, this service is still offered to ships at sea. All that is needed to receive these maps is an HF radio, USB soundcard interface and a computer running free, open source software.

Since my daily desktop computer runs Linux, I use an open source piece of software called fldigi, which may be obtained here. Fldigi is available for Windows, Mac and Linux. This software is like a swiss army knife of digital communication modes. In addition to WEFAX, fldigi can decode PSK-31, RTTY, MT63, SITORB and even morse code (CW)!

The frequencies and schedule of WEFAX transmissions are listed here.

The frequencies given are center frequencies, not the frequency that you set your radio to. WEFAX transmissions utilize upper side band modulation (USB). USB is 3 kHz wide. Since we are given center frequencies, we need the center of our transmission on the frequencies given. So we will be setting the dial frequency 1.5 KHz below the center frequency. For example: I wish to receive WEFAX transmissions from Point Reyes, California with a center frequency of 8682.00 KHz. We will set our dial frequency to 8680.50 in USB mode. (Remember, Since our radio is in USB mode, it will transmit a 3 KHz wide carrier so we will be occupying from 8680.50 to 8683.50, making our center frequency exactly on 8682.00 KHz)

Once the proper frequency is set in our radio, now we launch fldigi on our computer. Once in the program, we want to change our operation mode. We simply select the “Op Mode” menu and select WEFAX. For this service we want to choose WEFAXIOC576.

Once we have the software setup, we wait for a transmission to begin. As long as you have the proper settings on your radio and in the software fldigi will receive the fax images and save them to a temporary directory. You may wish to be at the computer when the first image comes through. This way if the image comes in at an odd angle (which, because of the varying nature of HF propagation, frequently happens), you can correct it and all following pages will download correctly.

To view a selection of WEFAX images I was able to download, please check out the WEFAX page. If you have any questions, please feel free to post them in the comments section. I’ll do my best to answer any questions.

fldigi in the process of receiving a WEFAX transmission.

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The Porky Show – January 16

PorkyShow2016

ATTENTION PATCH COLLECTORS!

The Porky Show, California’s longest running police and fire patch, badge and collectibles swap meet will take place on Saturday, January 16th in Claremont from 9 AM to 3 PM. The show is put on by the Claremont Police Department raises funds the Claremont Police Explorers program.

If you are interested in police and fire badges, patches, buckles, photos, historical documents, hats, helmets, cuffs, t-shirts or pins, this is the place for you!  Admission is only $5.

For more information see the flyer below or go to www.theporkyshow.com.

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porky2 porky3

 

Porky_2016_Flyer

 

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Future of OTA TV Broadcasts Uncertain

SCMA club member Steve Herbert (LA-187, K6CRW) forwarded me this article on the future of OTA television broadcasts. The following is from a tvnewscheck.com article:

It’s difficult to pinpoint any single year in the history of television broadcasting more momentous than 2016 is likely to be.

And when I say broadcasting, I mean the medium, not the business of assembling a linear TV channel of national and local (mostly news) programming and supporting it with revenue from advertising and retransmission consent fees.

mt_wilson_1_lgThe two have been intertwined since the beginning, but not inextricably. The business could presumably exist and perhaps thrive without the medium by relying on third-party distributors — cable, satellite and broadband.

This is the year in which policymakers and broadcasters will decide whether the medium is worth preserving, whether it is worth its weight in spectrum, whether it is worth a major investment to upgrade.

The decision will come in the way they conduct themselves in the repacking of the TV band that will follow the incentive auction this spring and how far they go in embracing the next-generation broadcast TV system known as ATSC 3.0 that is just about ready to go.

If all goes according to plan, in the incentive auction the FCC will buy a big swath of TV spectrum and sell it to wireless broadband companies. In the process, it will eliminate as many as 400 full-power TV stations that choose to sell or double up on other channels.

That, in turn, will trigger the start of a forced mass migration of between 800 and 1,200 of the remaining TV stations to new channels as the FCC repacks the old TV band to segregate broadcasting and wireless so they don’t interfere with each other.

For the rest of the article, check out the tvnewscheck.com article.

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SCMA Member Photographs End of Santa Monica Pursuit

 

SCMA member Bob Yuan (KJ6UVT, LA-189) captured these images at the ending of a pursuit in the city of Santa Monica. Police were chasing a carjacking suspect who stole a black Maserati at knifepoint. The suspect was arrested after crashing the car.

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SCMA Member Captures Pursuit Aftermath

SCMA member David Leon (KF6MBC, LA-154) was able to capture the aftermath of a long lasting pursuit across 2 counties. David heard the conversation on our club repeater and decided to swing by the termination of the vehicle pursuit on his way home from work.

The following article is from Jane Yamamoto and Willian Avila of NBC L.A.

Suspected mail thieves, believed to be a family, led authorities on a pursuit in Southern California, driving in opposite lanes and narrowly missing other drivers in rush hour traffic, before being taken into custody at a gas station on Friday.

Neighbors reported seeing two men taking mail, including packages, in the Nellie Gail Ranch neighborhood before taking off in a vehicle in Laguna Hills, said Jeff Hallock, spokesman for the Orange County Sheriff’s Department.

Sheriff’s deputies were dispatched to the 25000 block of Buckboard Lane after neighbors reported seeing the men taking mail from their mailboxes, according to a news release from the Orange County Sheriff’s Department.

The chase made its way through surface streets in several Orange County cities including Santa Ana and Anaheim, before the driver took the northbound 5 Freeway into Downey, where he and two passengers were taken into custody after pulling into an Arco gas station.

The California Highway Patrol was also involved in the pursuit.

Authorities arrested David Brown, 45, Anaheim, Jessie Brown, 55, Anaheim, and Corey Richardson, 22. All three suspects were from Anaheim, according to the Orange County Sheriff’s Department.

Photos courtesy of SCMA member David Leon (KF6MBC, LA-154)

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City of Los Angeles Ends LA-RICS Membership, Plans to Build Own LMR System

Los Angeles City SealLos Angeles City Council members voted unanimously November 18th to opt out of its membership the the Los Angeles Regional Interoperable Communications System (LA-RICS), citing potential cost advantages by taking the action and plans to deploy a new city-owned land-mobile-radio (LMR) network during the next 13 months.

“It is in the City’s best interest to opt out of LA-RICS, because the City will be able to upgrade its existing system and use existing infrastructure at a lower cost, while still achieving interoperability within the region,” according to a report provided to council members by the city’s Chief Legislative Analyst (CLA) Sharon Tso and City Administrative Officer (CAO) Miguel Santana.

Council members approved the measure by a 12-0 vote. During the meeting, there was no council discussion or verbal description of the measure, which was referenced publicly only as “Item 31.” The matter was discussed on Tuesday by the city council’s public-safety committee, which allowed public comment on the matter.

During the past month, there had been considerable speculation that the city of Los Angeles would opt out of LA-RICS, according to multiple sources. Indeed, the possibility has been discussed for most of this year, but city officials have played key roles in revamping the design of the LA-RICS public-safety LTE network and in getting Congress to pass a law that apparently will give LA-RICS a five-year extension to use federal grant money.

LA-RICS recently completed construction of the first phase of its public-safety LTE system, which was reduced from 232 sites to 77 sites—21 of which are owned by the city of Los Angeles—as part of a redesign approved by the Los Angeles City Council in the spring. LA-RICS also plans to build a P25 network in the region, but design plans for that system have not been finalized, as environmental requirements are not expected to be done until mid-2016, according to the report.

With the council vote, the city of Los Angeles no longer is a member of LA-RICS, although it will remain an LA-RICS affiliate that can subscribe to the network and provide infrastructure assets, like towers. By taking the action before a Nov. 24 deadline established by LA-RICS, the city of Los Angeles will not be financially liable for any additional costs associated with LA-RICS deployments, as well as the potential of having to repay Los Angeles County for funds it provided to LA-RICS during the past two years, according to the city report.

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HAMCON 2015 Photos

SCMA member Glen Rothstein (LA-145, KK6OTP) was kind enough to provide his photographs of HAMCON 2015. HAMCON (also known as the ARRL Southwestern Division Convention) was held this year on September 11-13th in the City Of Torrance.

The convention featured displays from equipment vendors, tech talks, demonstrations, VE testing, T-hunting (radio direction finding) and much more.

LASO DCS Truck Antenna Patch-COLLAGE (1)

To view all of Glen’s photos, please see the HAMCON 2015 page.

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V-22 Osprey Aircraft in Town for Presidential Visit

Nighthawk Flight-0009

In case you haven’t heard, President Obama is coming to Los Angeles on Saturday, October 10th.

From a CBS L.A. article:

LOS ANGELES (CBSLA.com) — President Barack Obama will make a roughly 6 1/2–hour visit to Southern California Saturday to attend a series of Democratic fundraisers.

Obama is scheduled to arrive at Los Angeles International Airport at 1 p.m. Saturday, according to the White House. He is scheduled to depart at 7:25 p.m.

While in Los Angeles, Obama is expected to take part in a roundtable discussion at the home of “Star Trek” and “Star Wars: The Force Awakens” director J.J. Abrams, with tickets costing $33,400 per person, according to Variety. Proceeds will benefit the Democratic Senatorial Campaign Committee.

The president is also expected to attend a concert by a mystery performer at a private home in the Pacific Palisades, according to various Hollywood trade magazines. Tickets for that event cost between $1,000 and $5,000, with proceeds benefiting the Democratic Hope Fund, which supports the Democratic National Committee and Obama for America.

Obama will also attend a dinner at the home of interior designer Michael Smith and his partner, former HBO executive James Costos, the U.S. ambassador to Spain. Dinner tickets range from $10,000 to $33,400 and will also benefit the Democratic Hope Fund, according to Variety and The Hollywood Reporter.

Club member Chester Brown (LA-203 and K6CRB) provided us with his photograph of a US Marine Corps V-22 Osprey. 

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Adam 12’s Martin Milner LAPD End-of-Watch Broadcast

The LAPD End-of-Watch Broadcast for Adam 12 actor Martin Milner (Officer Pete Maloy). This broadcast was recorded by Shaaron Claridge (now Shaaron Snead), the original voice of the dispatcher on Adam 12.

 

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Redondo Beach PD/FD Open House

The Redondo Beach Police and Fire Departments will be having their annual open house this Sunday, October 4, 2015. The event will be at the Redondo Beach Civic Center from 10 am until 3 pm.

Members of the public can shoot a handgun at a video simulator which simulates sudden occurrences in which a police officer must make an instantaneous decision whether to shoot or not. Other aspects of the police and fire departments will also be on display.

On occasion, other organizations, such as the California Department of Fish and Game
wardens have also participated in the event.

Source: SCMA Member Dominick Falzone, LA-125 

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