W4WVP

The meeting began with a presentation by Ken, WB4AKK on How to Build a Stealth Mobile Antenna on a Tight Budget. President Norton called the meeting to order at 8:00 PM. The Treasurer gave his report.

ARRL – Dennis reported the League had filed comments with the FCC on all pending issues. This should enable the FCC to act on these issues. He invited members to check out the Roanoke Division website. For DX confirmation, it was noted that International Return Coupons are no long available from the Postal Service. Advice was provided on how to facilitate written responses from DX contacts. Dennis also noted that use of the Log Book of the World would serve to confirm DX contacts.

Encomm – Gary noted the two up coming events was the Reagan Airport Drill on Sept 18th and the Marine Corp Marathon on October 31st. A form for participating in the Marine Corps Marathon will be posted on the web site. Our ARES net continues to run on schedule with good participation.

Members were encouraged to come up on our repeater following emergencies, such as the recent strong thunderstorms that hit the area. We were also encouraged to be capable of using the 449.325 MHz repeater that covers Arlington county fairly well. Members were also encouraged to work on their ISO 100 and 700 certifications.

CERT – Cynthia noted that CERT classes will begin on September 16 and 21st. These classes run for 8 weeks. About 450 Arlington residents have been trained by CERT and about 250 remain active in CERT.

Other news – Mike will make a montage of Field Day photo and post it on the web site. Dennis provided a gift to the club of two digital clocks. Folks interested in a presentation on traffic handling should speak to George about that interest.

The meeting adjourned at 8:45 PM

In attendance were: Ken WB4AKK, George KR4MU, Chuck KI4DHW, Dennis W4PWF, Mike KG4RKL, Arthur W4ART, Roy KI4GO, Gary KC5QCN, Jim AA0J, Randy WB4MJF, Erik KI4BXU, Mike KA8OPJ, Mike NW3V, Cynthia KJ4CLK, and Bill (Visitor).

Posted per request of ARRL Roanoke Division Director and AARC VP Dennis Bodson, W4PWF, Wednesday, 2010-08-11:

Fred Field is compiling an obituary for Walt for their high school. Both he and Walt went to the same school. He would appreciate it if we could put a notice up on our website requesting any information about what Walt did while up here in this area. Information for Fred is as follows:

Fred W. Field
1516 Avenida Selva
Fullerton, CA 92833
714-871-5767

Building an HF Stealth Antenna within a Tight Budget
Ken Heitner WB4AKK

Arlington Amateur Radio Club
Operating Mobile HF is Potentially Fun & Useful
The key problem with HF mobile is the antenna.
Various HF whips over the years have come and gone
Most HF mobiles today use the screwdriver antenna. You can build your own??
Maybe the approach used in the Stealth HF antenna is the way to go.

An Example of a Stealth HF Mobile Antenna
Another View of Stealth Antenna – See the Radiating Element

Can We Afford This ? – No. Can We Build This? – Maybe
This is a commercial product, and that means expensive
But if the concept is valid, maybe we can build a simpler and cheaper version
So let us examine how it works

Operating Concepts – 1
The basic antenna concept is a magnetic loop antenna
The 50 ohm coax feeds the antenna via a small loop.
The main loop is tuned to resonance by the high voltage capacitor

Operating Concepts – 2
The Stealth antenna is build on a modified loop concept.
The coax feeds on side of the antenna, in what might remind you of a gamma match
The loop is also tuned by a HV capacitor

Operating Concept – 3
Yet another feedpoint concept is the omega match
This concept is offered in the loop matchboxes made by MFJ
This may be easier to tune for a perfect match

Operating Concept – 4
This approach might be good for those whose radio already has a built in antenna tuner
It just steps up the low antenna impedance with a wide band transformer

General Project Approach
Simplify the antenna geometry so it is easier to build
Build the basic antenna framework first
Consider alternative feedpoint approaches for trial and error testing
Who knows – Maybe one of us will come up with even a better way to do this

Simplified Antenna Geometry- Plan View
Simplified Antenna Geometry – Elevation View

Simplified Antenna Geometry
Makes the antenna buildable from commonly available copper and PVC pipe
Once the basic antenna is built, then we can try different feedpoint concepts and see what we like. Each antenna can be customized for your vehicle roof size

Discussion Time !
Let me hear who would be interested in trying this project out.
Let us leave the details for a separate meeting of those specifically interested.
No rush….We can do this at our own pace
Might be fun for the next VA QSO Party.