Yearly Archives: 2017

Ham Radio: 2017 Eclipse Experiment

A map of the United States showing the path of totality for the August 21, 2017 total solar eclipse. (Source: NASA)

Many thanks to SWLing Post contributor, Colin Newell, who shares a fascinating 2017 eclipse experiment outlined on the website HamSCI.

Here’s the summary of the experiment:

On 21 August 2017, a total solar eclipse will traverse the continental United States from Oregon to South Carolina in a period of just over 90 minutes.

Previous research shows that the shadow of the eclipse will impact the ionospheric state, but has not adequately characterized or explained the temporal and spatial extent of the resulting ionospheric effects.

HamSCI is inviting the amateur radio community to contribute to a large scale experiment by participating in an Eclipse QSO party and further developing automatic observation networks such as the Reverse Beacon Network.

Data resulting from these activities will be combined with observations from existing ionospheric monitoring networks in an effort to characterize and understand the ionospheric temporal and spatial effects caused by a total solar eclipse.

Click here to read the full detailed experiment at HamSCI online.

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eBay find: 2:1 Remote/Local Antenna Switch $26.99 shipped

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Many thanks to Kenneth Crips who recently shared an eBay link to this antenna switch on the Gary J. Cohen’s Shortwave Listeners Global Facebook page.

The switch is not a kit–it is pre-built and appears to contain quality parts. The manufacturer, Electro Resales, makes a number of other products for the radio, astronomy, RC and model railroad markets. They have 99.9% positive feedback and a deep history of sales via eBay.

I’ve pasted the product description from eBay below:

Coaxial Electronic Switching unit for Antenna – 2:1 unit – Ready Built Unit

Switch 2 antenna to one radio or 2 radio to one antenna.

Using high quality Schrack Brand relays this antenna switcher works up to 200 MHz with SWR below 1:1 and minimal insertion loss.

Features include:
1. SO-239 input/output connectors
2. 8 Amp switching relay (Operation to 1 KW)
3. LED mimics indicate which port is active
4. Built in push switch for ease of operation – Selects relay coil to energize,
5. Remote installation operation possible
6. 1 KV Suppression capacitors and back EMF diodes on each relay coil
7. Relay coil : Capacitor tank frequency = 93 KHz – Minimizes RF interference on activation.
8. PCB Isolation Slots to minimize cross talk
9. 12 volt operation
10. Via stitching in critical signal paths and connector ground plane
11. Complete, self contained unit, ready to use. Not a Kit.

PCB dimensions are 4″ x 3.25″ (100 mm x 80 mm). Ready to mount in your installation

Pictures illustrate actual item that you will receive.

Questions – Please ask – Free Shipping as always

Sale includes:
1. Finished PCB with all components
2. Link to our on-line user guides

No other items such as power supplies, RF equipment or cables are included in the sale

I might purchase one of these as I have a remote antenna box with a solar-powered LDG ATU. This switch would allow me to change antennas without manually changing feed lines outside. I had planned to build a switch like this with my buddy, Vlado (N3CZ), but the price is awfully enticing! Have any SWLing Post readers purchased from this store before? If so, please comment.

Click here to view on eBay.

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Court of Dreams: How shortwave radio lead to a lifelong obsession with tennis

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Many thanks to SWLing Post contributor, Dan Robinson, who shares the following video from CBS Sunday Morning and notes:

For those who may have missed this recent CBS Sunday Morning piece, which tells the story of a guy who, inspired by BBC broadcasts of Wimbledon, built his own top-level court in Iowa. It’s not often that shortwave gets such national exposure:

https://www.youtube.com/watch?v=UF20Cem5ado

(Via CBS Sunday Morning on YouTube)

“If you build it, they will come.” In the case of one tennis-obsessed fan who built a replica of Wimbledon’s center court on his Iowa farm, people have come from around the world to his All-Iowa Lawn Tennis Club, to play on his court of dreams. Steve Hartman reports.

Click here to view on YouTube.

This absolutely made my day, Dan! Thank you for sharing.

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Video: TX Factor Episode 17

Radio Erena: “a symbolic lifeline” to Eritrea

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(Source: The Guardian)

[Radio Erena founder, Biniam Simon, writes:] “You have to understand: Eritrea is completely closed. No information is available there at all, about the outside world or what is going on internally. So if you’re an Eritrean journalist, and you make it to a place where so much information is available, the first thing you think is: why not tell people all this? It was the obvious thing to do.”

[…]The station broadcasts a two-hour programme in Arabic and Tigrinya seven days a week, repeating it several times a day, giving listeners inside Eritrea multiple opportunities to listen (they may do so, in the privacy of their own homes with the shutters closed and the sound turned down, only when electricity is available – which it often isn’t). As well as news about what the regime may be up to, it provides a detailed picture of what is happening to the refugees who are travelling to Europe – when a boat carrying 360 Eritreans capsized off Lampedusa in 2013, a correspondent was immediately dispatched to Italy – as well as features about diaspora success stories, footballers and athletes among them.

It runs smoothly. There is always a lot to tell. Making sure it can be picked up in Eritrea, however, remains a constant struggle. In 2012, the government managed to block it – seemingly unbothered by the fact that in doing so, it also blocked its own television channel (both broadcast on one satellite frequency). It has also successfully jammed it on shortwave, and on at least one occasion has hacked into the Radio Erena website, destroying it completely. “It’s a nonstop challenge,” he says. “We’re constantly fighting them, and it’s getting harder and harder because they are now employing new experts from China and Indonesia.”

But if this is exhausting, it’s also hugely encouraging: “It means that what we’re doing is working. We know this because the government wants us to stop.”[…]

Readers: this is only an excerpt from this excellent article in The Guardian. Click here to read the full article.

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FCC: Expanded use of marine HF frequencies on land

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Many thanks to an SWLing Post contributor who shares a link to the following public notice from the FCC:

Wireless telecommunications bureau seeks comment on request by Shipcom, LLC, and Global HF net, LLC, to allow use of high seas marine frequencies by first responders and federal agencies during disasters

Section 80.123 of the Commission’s rules permits very high frequency public coast stations to provide service to units on land under certain conditions, but does not allow high frequency (HF) public coast stations to provide such service. In 2010, the Wireless Telecommunications Bureau’s Mobility Division (Division) granted Shipcom, LLC (Shipcom), a waiver of section 80.123 to permit the use of HF public coast frequencies by first responders during catastrophic situations when normal communications systems are not available. The Division concluded that this limited use of HF maritime spectrum would enhance public safety during catastrophes. The waiver permits service to land-based (base and mobile) Public Safety stations on HF frequencies in the event of a natural or man-made disaster that renders the normal communications infrastructure inoperable, and monthly testing/training to familiarize personnel with how to operate the equipment and make sure it is operable.

Click here to download the full FCC Public notice (PDF).

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HAARP Open House: August 19, 2017

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Many thanks to Chris Fallen (KL3WX), Assistant research professor in the University of Alaska Fairbanks Geophysical – Space Physics group , who shares the following information about the upcoming HAARP Open House:

HAARP Open House 19 August, September campaign

The next HAARP open house will occur on 19 August 2017 and include round-trip bus transportation from Fairbanks for $45 which will help bring costs down for individuals, particularly for those from out of town.

(Flyer attached, though I am not aware of an official press release yet but updates will be posted at http://www.gi.alaska.edu/haarp)

Throughout the day there will be talks by Geophysical Institute researchers on-site about the HAARP facility and research, and other research topics pursued at the UAF Geophysical Institute. As in the previous year, tours of the main transmitter array, control center, and power generation plant will be offered throughout the day. Hams and radio enthusiasts are encouraged to bring their equipment for photo opportunities or even to make contacts from the site.