Meeting: "Military HF Radio Communications and Near Vertical Incidence Skywave Propagation”

Speaker: Captain Matthew Sherburne, KF4WZB / US Army Signal Corps
Time: Wednesday, December 4, 7:00 PM – 8:00 PM
Place: Squires, Mountain Lake Conference Room

Synopsis: HF communications allows us to communicate around the world by reflecting radio waves off the ionosphere. This mode of communication has allowed militaries to move farther and faster than ever before at least until satellite communications were launched. Learn how HF is still a viable means of voice and data communication for both amateur radio operators and the military.

I will cover the basics of HF radio-wave propagation followed by a history in military HF communications from WWII to today. Before communication satellites were launched, Near Vertical Incidence Skywave (NVIS) was the preferred method for communicating over mountains and large areas covering a 300-mile radius. I will discuss how various militaries adapted their vehicles to take advantage of NVIS communications and the current antennas in use today.

K4KDJ Makes a Clean Sweep!

I’m very pleased to announce that after a weekend of operating, K4KDJ has successfully completed a Clean Sweep in the 80th Anniversary of the ARRL November Sweepstakes SSB. This means that we successfully contacted all 83 geographic radio sections of the United States and Canada during the course of the contest. This is not an easy feat, and the club has not successfully done this for many years. A clean sweep is traditionally celebrated with a commemorative “Clean Sweep Mug,” which operators are eligible to purchase after completing the sweep.

K4KDJ to Participate in November Sweepstakes SSB

Virginia Tech Amateur Radio Station will put K4KDJ on the air for the 80th November Sweepstakes SSB Contest. Operations will take place 80-10 meters from Saturday, November 16 at 4 PM EST to Sunday, November 17 at 10 PM EST. K4KDJ has participated in this contest many times in the past, and has even won the Roanaoke School Division.

Sweepstakes is the oldest domestic amateur radio conest, and the rules of exchange are based on the header of formal radio traffic. In this contest, K4KDJ will be working to contact all 83 US and Canadian radio sections within the 24 hours of allowed operation time. For more information regarding the ARRL Sweepstakes, please visit

Meeting: High Power Radio: Megawatt Class Radar for Geospace Science

Speaker: Dr. Philip J. Erickson of the MIT Haystack Observatory (
Date: Wednesday, November 13, 2013 @ 7:00 PM
Location: Squires 219

The coupled near-Earth space system is a complex and dynamic region where both large and small scale physics governs our planet's reaction to space weather disturbances from our nearest star, the Sun. Much of this fascinating environment is invisible to optical techniques, but is revealed at radio frequencies in the centimeter wavelength range. Observing in radio usefully allows study of the terrestrial geospace system from the ground.

For more than 5 decades, it has been practical to scatter UHF radio waves off the free electron gas in the upper atmosphere, modified by the presence of charged ions, in a process known as Thomson or incoherent scatter. This most powerful of ground based techniques allows the natural plasma made each day by our sun's extreme ultraviolet radiation to be probed at appropriate space and time scales. However, the radar target provided by the ionospheric plasma is an extremely weak and variable one, requiring megawatt class transmitters, sensitive receivers, and large aperture antennas. Maintaining these subsystems and interfacing legacy transmitters to modern receiver hardware is a constant and unique challenge.

I will describe the general design and operation of radars capable of detecting incoherent scatter along with the use of these radars to derive the complete physical state of the thermal ionospheric plasma. Along the way, I will describe the basics of how plasma scatter occurs at tens of centimeter wavelengths. I'll also provide specific examples of radio and radar techniques used on a routine basis at the mid-latitude Millstone Hill ionospheric radar system, operated at MIT Haystack Observatory since 1960 as an upper atmospheric facility for the space science community. Some of these techniques will be familiar to the 70 cm radio amateur community. Finally, I will briefly describe some significant scientific results arising from these uniquely productive observations.

Meeting: 10 GHz Amateur Communication by Josh Arritt, KF4YLM

Speaker: Josh Arritt, KF4YLM

Date: Wednesday, October 30, 2013 @ 7:00 PM

Location: Squires 219

The majority of the spectrum available to Amateur operators resides above 70cm, yet most Amateur operators appear to be "stuck" in the 25% of ham-allocated bandwidth below this cutoff frequency. There is activity on the microwaves pursued by a mostly technically-minded corps. Since there are slim commercial radio package offerings out there, getting in on the action requires some basic technical and operational feats beyond those involved with the "appliance" HF station. It also helps to have some elmers in the area. Transmit power levels are disparate in comparison to HF (3W at 3cm is QRO!), which leads many amateurs to believe the microwave communication capabilities are for naught -- this is far form the case. Of the 11 microwave (900MHz+) multi-MHz-wide bands, 3cm (10GHz) is by far the most popular for terrestrial communications. The presentation aims at giving a brief history of this band, a world-view of 10GHz operation in the 21st century, and a glazing-over of the equipment which can be used to build, test, and operate on this unique and awe-inspiring band. Microwave operation is closer in reach than you may think!

Congratulations to New and Upgraded Hams!

Congratulations to all of the new and upgraded hams!  Once again, everyone passed at least what they came for.

We have 5 new Technician Licensees:

  • Jeffery
  • Cameron
  • Kennetth
  • James
  • Dale, WB2PVF (Upgraded from Novice!!)

We also have 1 upgrade to General:

Jamboree On The Air Success

As you know, a number of us were camping this past weekend with BSA Troop 704 of Blacksburg at the McDonald Farm just off of Prices Fork Road.  We had a really great weekend, and Scoutmaster Don Barker extends his thanks to the club for our efforts.

We had very good participation from the club, including Bob Schubert, KC4FNE, Ben Williams, KK4EWT, Shyam Nambiar, KK4ORE, John Dever, KD8UKE, Shenghou Ma, KV4RJ, Andy Armhein, KB3WPR, Mark Allamong, KK4QZF, and Nathaniel Frissell, W2NAF.

VTARA 2m FM Net report - Oct 17th, 2013

We had a wonderful turnout tonight on the weekly 2m FM net on the W9KIC repeater. Following were the stations who checked in -

KB4GIW - Bruce
W2NAF - Nathaniel
KK4EAB - Matthew Via
N3RQ - Samuel
W8RBT- Richard
N3PB - Phil Benchoff
W9KIC - Dr. Davis


School Club Roundup Fall 2013

Next week is the School Club Roundup, a contest that we participate in every semester.  Last Spring, we earned 7th place in the nation for the college/university division.  I encourage everyone to come out next week and help us beat last year's score!

A couple of rules:

K4KDJ Partners with Troop 704 for Jamboree On The Air (JOTA)

The Virgina Tech Amateur Radio Association will be camping with BSA Troop 704 of Blacksburg October 18-20 as part of the Jamboree On The Air (JOTA). JOTA is an international event which takes place the third full weekend of October every year in an effort to connect scouts around the world. VTARA will be running a 2-Alpha Field-Day style (2 HF transmitters running on emergency/generator power) operation from McDonald's Farm using the club call K4KDJ. K4KDJ will be QRV the evening of Friday, October 18 through Sunday morning.

In addition to using the radios, scouts will be building survival shelters Saturday morning and sleeping in them Saturday night.

For more information on Jamboree On The Air and Radio Scouting, please visit


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