With Varying Frequency - Amateur Radio Ponderings

The famous KK Fiske Restaurant on Washington Island (WI-001L) Wisconsin was the venue for a WI9DX Washington Island DX Club meeting.  

Founding Members George W9EVT, Mac W9EVI and Myself (Steve K9ZW) welcomed member Dean K3GGN and new members John KA9USC & Mike K9ABT

WI9DX DX Club was founded several years ago to promote Amateur Radio on Washington Island, specially the pursuit of DXing.  (DXing is the hobby of tuning in and identifying distant radio stations, or making two way radio contact with distant stations in amateur radio.)

These events are always great fun, as everyone has so much to share, finally gets to meet people with shared interests and always results in much camaraderie!

Of special interest this July meeting is interference noted by several of the members on 6m, 10m, & 12m bands.  Several audio recordings were played and discussed.  There is a strong correlation that the interference (which can range to over S9 across more than a hundred kilocycles in several areas at times) with a pilot data over power grid (BPL) program underway currently on the Island.  When running this interference is strong enough to deny the affected band segments from Hobby & Emergency Communications use.  

In true “Island cooperative style“, the group was unanimous to offer our assistance to try an firmly identify the exact source, and to help correct the in-Amateur Band interference.  Further consultation with Ed Hare W1RFI at the ARRL is planned to help define a protocol for offering Amateur Assistance.  As the ARRL has a working & acceptable BPL install to the League’s main radio station the group hoped that depth of experience would help sort out the local interference on Washington Island.

Antennas, rigs, mobile (including Marine Mobile) operations and station banter filled the rest of the morning’s meeting.  George W9EVT extended an invitation for all the members to come visit his shack, QTH at Greengate Farm.

73

Steve
K9ZW

One interesting side event at Dayton 2008 was to help George W9EVT find a replacement for one of his towers.

Spec was Motorized Crank-Up, 70ft, towards the heavier duty, but not extra-heavy.

Strong pull would be to be able to use the base already infor the tower being retired.

US Tower seemed to have the tower that best fit the bill and after a bit of back-and-forth arrangements were made, deposits placed and the wheels were in motion.

The Washington Island destination made shipping hard to figure out, taking a bit of extra checking with carriers.

 Worth noting is all the tower manufacturers are facing large raw material costs and transport costs.  Pausing just a  week or two can add 10% or more to a tower’s cost.

73

Steve

K9ZW

Great Ferry ride and drive back from Washington Island W9EVT, where we had booked again with George W9EVT and his XYL Susan. Memorial Day weekend on an Island, yeah! Adding to our Memorial Day observance is that George W9EVT is a Korean War era Navy vet and I spent my time in the Cold War Army.

Great time had by all!  Huge Thunder & Lightening Storm with Heavy Rains last night - power went down for a 1/2 hour across the Island.

The expanded “Ham Mansion” W9EVT/WI9DX Hamshack is moving along.  The main operating room will be 2-1/2 the length once the plasterers finish in the next few weeks.  The first of the theme rooms to be ready will be the “Collins Room” which was a couple days from being ready for moving gear in.

The rest of the “Ham Mansion” is a work in progress, all framed & closed in, with various areas ranging from needing just plaster, trim & paint to being open walls.  My understanding is the additional rooms will be progressed after the main room and Collins Rooms are completed.  

Various gremlins made radio work fall behind being helpful on other projects.  When we arrived the internet for the whole complex was down due to serious misguidance received from an On-Line call-in Tech Center somewhere out there.  Guidance from one of these “tech on the phone” led to a Router being used as NAT interface between the inside system and the Motorola Canopy system loosing all it’s settings.  

Certainly the phone tech meant well, and it very hard for a phone tech to visual what is a decidedly more complex than the average system, but the result was the entire system being unusable.  We had been called before we left, so we knew there was an awaiting troubleshooting exercise.

Having a go rebuilding the setting matrixes was a no-joy outcome.  Extremely puzzled I broke off for dinner and was very pleased when most of the system came back to life!  Seemed once the correct settings were installed that it took a while for the Canopy system re-authorize the network connection.  

A couple buildings I wasn’t able to hotrod the wireless back up to running, lacking the admin passwords to make corrections, but I was able to get plug in ethernet points up.

Always fun to trouble shoot a system you hadn’t designed or built, specially without full documentation.

The TenTec Omni VII received its bootloader update and full software updates.  I didn’t bring the correct cabling to update the Orion II, Icom IC-7800 and Yaesu FT-2000 units.  Next trip!

Working with the SPE Expert IK-FA it was clear that this particular example needs help - Expert has a new Level-III Update program to bring these amps up to spec.  George W9EVT is going to send it in for the warranty upgrades needed.

After the huge lightening storm - lightening could be seen running across the tree tops like a freight train at one point - we discovered the internet was again down, the phones were partially out and a few of the radios seemed to have reset themselves despite being disconnected and leads grounded.

The radios were a puzzler, as no direct hits were taken and nothing was “smoked” anywhere on the farm.  Guessing that the heighten airborne ambient energy was enough to “tickle” them.  At the peak of the lightening display you could feel a tingle while watching from a covered porch.

The internet turned out to be a wall wart to the same annoying NAT router that had not liked going onto battery backup and burnt out.  A trip out to th e workshop across the farm for a spare wall-wart (power cube) and all was well!

Phones were a bit more vexing, and by a process of testing & elimination we found a Direct-TV Satellite box in the Applehouse Master Bedroom had internally shorted out.  This is the second Direct-TV Satellite box to turn belly-up at Greengate this year (they have a bunch).   

Operating time was mostly limited to testing equipment.  

Did a spot of “poor man’s surveying” by using a GPS unit to pick out relative antenna base heights and spacings.  The unit I used is not highly accurate and perhaps is accurate, relative to the other points measured, by six feet (2m) or so.  As for absolute accuracy the entire plot should be within 50 ft (16m)  of actual.  I will use this data as a model the antenna array in NEC.

DIdn’t get the WI9DX work done I had planned, but hey there are only so many hours!

Far too short of a weekend.  great to get back onto the Island and at least get a few QSOs completed.

I need to ask permission to post the construction photos. Hopefully more to come!

73

Steve
K9ZW

Working at modeling the new Bruce Array for Washington Island

Here are PDF files of the various outputs from my first efforts in cocaoNEC:

40m-bruce-v2-geometry

40m-bruce-v2-elevation

40m-bruce-v2-azimuth

40m-bruce-v2-3d

73

Steve

K9ZW

On Washington Island WI-001L two Bruce Arrays have met their fate. The first was lost to groundskeepers who damaged it beyond reasonable repair with power equipement.

The replacement was lost when one of the support towers suddenly collapsed, as its crank-up cable perished from concealed damage.

A Third is in Modeling - with NEC2 models of various exact measurements suggesting a number of tweaks that should make “Third Time Lucky” a reality.

One issue in Number two was an unexpected difficulty in bringing the antenna into resonance exactly where we expected until a considerable amount of effort was made adjusting tuning stubs.

Models suggest that the feed point impedance was greatly higher than planned for, which likely exacerbated the “twitchiness” in tuning that version (Link to Article on Tuning that Array).

Bob Rumsey, KZ5R’s Balun Designs LLC #6113 6:1 Current Balun has been ordered for the feed point duties, after antenna modeling indicated that the antenna impedance is actually in the 300-325 Ω range, rather than the 200 Ω range assumed.

A Number of Design parameters are being used in doing the redesign and modeling:  

• Supports are 70 (max) tall at tie-off point.
• Supports are 125 feet apart.
• Target Frequency is 40m SSB Net & DX frequency range
• Feedline will be Coax to reduce interference & interaction with other feedlines & existing ladder line.
• A 10 foot headroom clearance under the antenna would be desirable.
• The Supports are Crank-Up Towers, so the antenna must allow for their movement.
• Design that would prevent the antenna being in the snow or on the ground when the towers are lowered would be a plus.
• The Antenna will be built in warehouse space in Manitowoc, and must be transportable to Washington Island WI-001L with little fuss.  (Link to Build Article)
• An easier method of adjusting resonance & element lengths is highly desirable.
• Once on the Island it must be simple to install.

It seems appropriate that this array is called a “Bruce Array” given the legend about “Try Try & Try Again” surrounding the ancient “Bruce” namesake Robert Bruce of Scotland:

According to legend, at some point while he was on the run during the winter of 1305-06, [Robert] Bruce hid himself in a cave on the east coast of Rathlin Island, where he observed a spider trying to spin a web. Each time the spider failed, it simply started all over again. Inspired by this, Bruce returned to inflict a series of defeats on the English, thus winning him more supporters and eventual victory. The story serves to explain the maxim: “if at first you don’t succeed, try try again.” 

There is a lot of differing information published on Bruce Arrays.  The Application of Wire Velocity Factors vs. Open Air factors is one discrepancy between various sources that would change the length of a 40m Bruce Array by 4m in length alone!   In one case a 5% shortening, specially of the end elements, is suggested, while other sources add 5% to the direct length calculations, calling out an “array factor.”

Given that each of the previous two Bruce  Arrays needed wire extensions to come in-band I will be studying this one carefully!

Should have some new models and figures to post for comments right after the Dayton Hamvention.

73

Steve

George W9EVT’s Greengate Farm Hamshack has undergone a bit of a transformation.

It is now approaching four times as big!

As George’s XYL Susan did a serious upgrade with a new kitchen & build-out at the main Greengate Farm Home, the Ham Shack has started its transformation to a Ham Mansion!

While accomidations at Greengate Farm remain the same as before the expansion, the Ham Mansion will offer a significant increase in space to show off the best of George W9EVT’s collection of radios and related gear.

This is very nice for the WI9DX DX Club when operating from the W9EVT QTH.

Greengate Farm Main Website

W9EVT’s Greengate Farm Ham Shack/Mansion

 With the new Ham Mansion closed in, a room by room finishes & completion project starts, one that may take some time as just the right furnishings & radio gear are set up for the Radio Rooms.

George W9EVT shared that the master plan includes separate rooms for Military Radios, several of the major US Manufacturers, and a significant extension of his main operating area.

Not only does the expansion and theme operating rooms make the W9EVT Ham Mansion special, the location on Washington Island Wisconsin (US Island WI-001L) and available rental accomidations on site make it a unique combination.

More on the W9EVT Greengate Ham Mansion to follow!

73

Steve