The band was relatively quiet in Texas over night with early openings and subsequently early reports from KC2QII in Florida prior to darkness. Activity seemed to be OK for the last session of May and while storms were scattered across the US, widespread communications disruption that have recently been seen were not noted.
Geomagnetic activity was elevated but quiet. The Bz is pointing to the South and solar wind velocities are exceeding 450 km/s. The Kyoto DST remains steady while the Australian DST continues to indicate disturbed conditions. The path between VK and KH6 has been fantastic in this session and the previous, however.
John, WA3ETD / WG2XKA, received WH2XGP on the high latitude transcontinental path:
Neil, W0YSE/7 / WG2XSV, reports a quiet, lean session in Vancouver, Washington:
Joe, VO1NA, continues to be reported by Roelof, PA0RDT. The previous session brought Joe’s signal in a noisy passband but obviously visible in the waterfall. After the reports from Stefan, DK7FC, Joe extended his operating into this session.
Rick, W7RNB, submitted his application this weekend and after being open for business for only 3-hours this morning, FCC’s OET has assigned WI2XJQ. Now we wait for NTIA to do their part. My guess is that a one month turn-around is not out of the question. As rules are established for Part-97, the process is being streamlined and there does not seem to be the same level of scrutiny seen in the past.
PU3VWR/SWL was present in this session using WSPR but was reporting the old frequency of 503.9 kHz. Its unclear whether he is actually listening on the wrong frequency or simply accepting the default reporting of the software while the rig is set up properly on 474.2 kHz USB. This past Winter when this station was last QRV on the wrong frequency I was able to find an email address but got no response. If anyone knows how to contact this station, it would be great to find out his situation and operating conditions. I don’t think the path to southern Brazil from North America would be insurmountable given the success of the path between Europe and Reunion Island.
The foreword can be viewed here and Doc provides these additional details including ordering information:
Regional and continental WSPR breakdowns follow:
There were no reports from the trans-African path during this session. UA0SNV was present but no reports have been filed at this time.
In the Caribbean, Eden, ZF1EJ, reports WH2XZO and WG2XIQ:
Laurence, KL7L / WE2XPQ, continues to be very consistent while operating in receive-only capacity, decoding WH2XCR, WG2XSV, WH2XGP:
Merv, K9FD/KH6 / WH2XCR, received very early reports in Australia and shared two-way reports with VK4YB and VK3ELV. Its rather remarkable how propagation can improve so much, so quickly. Will the JA path return soon?
Jim, W5EST, compares modeling packages in this discussion entitled, “MMANA-GAL COMPARED WITH EZ-NEC DEMO”:
“Housekeeping preface: I hope to do daily submissions Tuesday through Friday this week. Then: no submissions, as I’ll be visiting family through June 12. After that, I look forward to doing some ad hoc submissions to this blog through end of July. Thanks for the time you have spent reading these little articles during the last several months and benefiting all of us through your e-mails !
Today, I return to antenna modeling with a brief comparison of MMANA-GAL with EZ-NEC Demo. Both are free programs on websites that commercially offer higher-end versions. The free version of MMANA-GAL offers lots of Segments/Wires/Sources/Loads —8192/512/64/100. So its flexibility is appealing when you want to model more complex antenna geometries and antenna systems with multiple phased antennas and elements.
Recall from this blog April 25 how to Load/install your selected antenna modeling software. https://www.eznec.com/demoinfo.htm brings you EZ-NEC Demo.
Get a MMANA-GAL download from http://gal-ana.de/basicmm/en/ . Below its tutorial, scroll to bottom to download its free version, which comes with some already-created antenna files. You can open any of them in MMANA-GAL and then tweak, starting from the antenna specifications they represent.
Steve G0KYA provides slides with antenna examples and more links: http://g0kya.blogspot.com/2012/03/using-mmana-gal-for-antenna-modelling.html
Just below the link to Steve’s slides there’s a second clickable link
Download the MMANA-GAL antenna files . When you’ve reached the filenames of those additional antenna files, file-block-copy them into your hard drive at C:\MMANA-GAL_Basic\ANT\Receive using keyboard Ctrl-Shift-DownArrow to block them all. Then mouse-right-click Copy and then Paste into that ANT\Receive folder.
Now click on the MMANA-GAL icon on the desktop to bring up a toolbar and do File-Open on an antenna type. I chose a K9AY loop. Fortunately, you’ll see some familiar words and symbols in MMANA-GAL if you’re already acquainted with EZ-NEC Demo. That makes sense since both packages address many same antenna problems.
In MMANA-GAL click Calculate and specify the Ground (like Real Ground) you associate with your antenna model. Click the Start button at lower left of the Calculate screen, and then click “Far field plots” up at the toolbar. On the Far field display, get acquainted with the various features to see the “V” vertically polarized and “H” horizontally polarized fields individually, overlaid, and totaled. For the azimuth plot, don’t forget to click “Elevation” at the bottom to specify its pertinent elevation angle.
The bottom-center “3D FF” button brings up a 3D plot that you can mouse around to different orientations to more fully reveal the whole antenna pattern, such as the unidirectional K9AY pattern. You can see some results of antenna calculations along with the pattern.
On this MMANA-GAL get-acquainted tour, we next encounter the Geometry option upper-left on the toolbar. The Geometry window lets you specify and add/delete/edit Wires, Sources, and Loads. A little concentrated X,Y,Z practice specifying wires will pay you dividends.
To edit an X,Y,Z value, click on a value, such as in the X1(m) column, enter the value you want, and press the keyboard Enter key to enter it. Check your wires by clicking “View” and “Geometry” alternately until you’ve specified the wires according to an antenna geometry you want.
Specify the operating frequency in megaHertz, up to three decimal places such as “0.475” for 630m. If you have multiple antennas, phase their Sources and indicate their voltage amplitudes.
In the “Loads” section, I prefer the Load Type “R+jX” if it’s not already indicated. Otherwise, click twice (slowly, not usual double-click) on a cell and choose “R+jX.” Then enter a value in the next two cells. To specify the resistor for a K9AY loop, put a several-hundred-ohms value like 450 in the R cell and zero 0 in the jX cell. Don’t forget to key-press Enter on the keyboard to enter each value.
Those features suffice to get some basic modeling done. MMANA-GAL has lots of other features for you to explore. I’ll just mention a couple.
On the toolbar, click on the wrench-and-hammer symbol, second from right. This “HF components” window lets you add a loading coil, an LC network, etc. Among other toolbar symbols, several of them help you speed up editing the wires.
On the Calculate screen, “Optimization” generally helps you find best antenna design values among various competing desirable criteria. When you click the Optimization button there, the screen shows a table. Click on an empty cell under “Type” to select your choice(s) of sweep: Wire, Element, Load, Height, Frequency, and Source. I chose “Frequency” and then entered values for Step, Min, and Max. Next, press “Start” at bottom right to generate a table of results that includes SWRs. Sometime I want to learn how to make MMANA-GAL automatically graph those SWRs like EZ-NEC Demo does.
On each of MMANA-GAL and EZ-NEC Demo I also tried to run a side-by-side comparison of a 70’ (22m) 1.5” dia (19mm radius) vertical antenna 3’ (1m) up from 5mS/m real ground. Both programs showed highly capacitive antenna impedance including radiation resistance less than one ohm, but beyond that the values weren’t very close. I’m still learning how to align the results. But both programs apparently show the same antenna patterns peaking at 21° elevation.
Tell us about your successes and lessons learned on MMANA-GAL!”
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD gmail dot (com)!