SOTA Antennas -- FREE Antenna Modelling Software

 

https://sota-antennas.com/

Ed DD5LP writes: 

Hi Bill,
 Given that the audience of SolderSmoke is more angled towards home brew and self construction, I wonder if you would mind informing your listeners of a very valuable antenna design website that despite the high level of quality work put in, is not getting very many visitors and may therefore be taken down.

Access to the site is free and the URL is sota-antennas.com.

 https://sota-antennas.com/

Despite SOTA being part of the name this is of use for all portable operators and indeed home stations as well. It is a series of online tools that not only defines wire lengths for building but also gives EZ-NEC like diagrams of the expected radiation patterns.
My favourite little jewel is in the off-centre-fed dipole section where the positioning of the feed-point is varied automatically to show you the bands the antenna will resonate on. So as an Example a 40m OCFD with a feed-point at 33/66% will not resonate on 15m however one with the feed-point located somewhere near 18/82% will.

The website currently supports Linked-Dipoles, Off Centre Fed Dipoles, End Fed Half Waves, Delta Loops, Half Squares and Moxon antennas. It could be extended to support others but that is unlikely if the current site is not used more.

Thanks Bill!
73 Ed DD5LP

Mostly DIY RF's Kit of Pete N6QW's P3ST

 

There it is.  Truly a thing of beauty. Order yours today!  

https://mostlydiyrf.com/p3st/

Long-time SolderSmoke supporter Ramakrishnan VU2JXN Interviewed on QSO Today

 

https://www.qsotoday.com/podcasts/vu2jxn

I think we got our first e-mail from Ramakrishnan way back in 2006.  At the time he was VU3RDD. On June 22, 2008 in SolderSmoke #86 we reported on the birth of Ramakrishnan's new harmonic.  In this interview with Eric 4Z1UG we hear of Ramakrishnan's daughter (the same harmonic) getting her ham license and working with her dad on electronic projects.  Ramakrishnan has been with us for a long time!  

It was very cool to hear Ramakrishnan talk about the Lamakaan convention, the BITX 40, and the book The Electronics of Radio.  There was a nice mention of SolderSmoke and Pete. 

Listen to the interview here:  https://www.qsotoday.com/podcasts/vu2jxn

Thanks Ramakrishnan!  Thanks Eric! 

Happy New Year! Straight Key Night at N2CQR (video)

As you know, here at SolderSmoke East HQ we are all about TRADITION.  So last night (New Year's eve) I fired up my venerable HT-37 / Drake 2-B combo and made a few Straight Key Night (SKN) contacts on 40 meter CW.  I was indeed using my straight key.  Video above. 

Also, be sure to check out CuriousMarc's very cool New Year's clock video: https://www.youtube.com/watch?v=YZmEz-Y1FFM

Happy New Year to all.  May you make good progress on your homebrew projects, and may the radio gods act favorably on your behalf.  

73 es HNY de N2CQR 

South African Homebrew: ZS4L's "Griffin" 40 Meter SSB Transceiver

 

That's William, now ZL4L, and his homebrew 40 meter SSB transceiver.  He has given the rig a wonderful name from Greek mythology:  The Griffin (see below).  I talked to William this morning on 10 meter SSB.  I mentioned my homebrew rig and to my surprise (this doesn't happen much) he asked for more info.  Then he told me about his own homebrew creation, The Griffin.  FB William! 

-------------------

From William's QRZ.com page (https://www.qrz.com/db/ZS4L):  

I have always wanted to build a homebrew transceiver-and recently I completed my pride and joy-a 40m SSB/MCW transceiver-I call it the ZS5WC "Griffin"..

"Griffin"..-well --if you know greek mythology you will find that it defeated much greater adversaries in battle.(to cut a long story short..)
The parallel I am getting at is..Big commercial rigs can be taken on by a rig constructed at home-and with great success!.
Sure, it does not have the bells and whistles of a 1000mp-but the TX audio is good, the RX is great , and the SMILE factor-even with all the little quirks is off the scale!..
Basically it is a single conversion superhet-4 tuned BPF stages,ATT, Gain control stage ahead of 1st Rec. Mixer/Bal. mod (NE612) , Xtal 10mhz homebrew filter,2 transistor feedback amp, second gain control stage,2nd mixer/BFO (NE612)-On TX to PA board-4 transistor pre-amp, IRF510 mosfet PA, LPF and RX /TX relay. ON RX to TL072 audio pre-amp, Spits to AGC/S-meter amp-(741 and BC107's) and audio amp TBA820m.
ALC is done on AGC board as well with BC107 back to back to AGC bc107.
The S-meter drive is developed in the emitter leg of the AGC BC107-simple series pot to calibrate-no zero pot is required..(Works great!)
There is a volt control PCB too, with RX/TX switching.
On the main PCB there is a phase shift osc. for MCW and sidetone. Alc is adjustable from front panel from 1/2 watt to 5 watt.Rit is included in the Hartley osc. circuit and readout is done with a pic and two line LCD disp.(from AADE.com..)
Freq. drift from warm is 200Hz down in frequency then swings round and stabilises close to start freq.
Rit is good for around 5Khz swing.
Amp keying is available on the back panel, as well as an aux. 12 supply-(To run a homebrew noise squasher and amp..)

https://www.qrz.com/db/ZS4L

7J6CBQ on Okinawa -- And a Translation of a Science Fiction Novel about Ham Radio in China

 

The article about Sergeant Malik Pugh USMC on Okinawa brought back memories from the 1990s. David Cowhig was 73 Magazine's Hambassador on Okinawa -- I had the same "position" in the Dominican Republic.  David and I were both in the Foreign Service;  we joked that 73 had afforded us our only chances to be ambassadors of any kind.  David's Okinawa QSL and the opening from his initial report to 73 magazine appear above.  You can see more here: 

https://archive.org/details/73-magazine-1992-12/page/82/mode/1up

• https://archive.org/details/73-magazine-1993-04/page/82/mode/2up
• https://archive.org/details/73-magazine-1993-04/page/84/mode/2up
• https://archive.org/details/73-magazine-1993-04/page/86/mode/2up

https://archive.org/details/73-magazine-1993-06/page/76/mode/2up

https://archive.org/details/73-magazine-1993-07/page/82/mode/2up

https://archive.org/details/73-magazine-1993-08/page/78/mode/2up

https://archive.org/details/73-magazine-1993-11/page/84/mode/2up

https://archive.org/details/73-magazine-1993-12/page/78/mode/2upmode/2up

A couple of my own "dispatches" as Hambassdor to the Dominican Republic appear here: 

https://www.gadgeteer.us/DRDISP.HTM

Back in the 90's David sent me an old QST Magazine.  I wrote about this on the SolderSmoke blog: 

https://soldersmoke.blogspot.com/2015/07/been-there-done-that-he-begged-his.html

Later, I learned about another "Hambassador" who was still active as a radio amateur: Ron Gang 4X1MK:  

https://soldersmoke.blogspot.com/2017/10/ron-gang-4x1mk-on-qso-today-podcast.html

Finally (and this is really cool):  David Cowhig has been putting his language skills to good use, translating Chinese written material.  He sent me his translation of the opening chapters of a Chinese science fiction novel about ham radio.   Readers of the SolderSmoke Daily News will like this: 

https://gaodawei.wordpress.com/2021/12/18/chinese-sf-ham-radio-web-novel-we-live-in-nanjing/

We Live in Nanjing 《我们生活在南京》

Thanks David! 

Around the World Twice (and maybe more) on 15 meters

 

John EI7GL has a great blog post about some experiments recently done by Salvador EA5Y.  Salvador was aiming his 4 element yagi in one direction, sending dits, and watching for the signal to come around the other side.  You can see the results in the display above.  I commented that this might be the time for one of those antennas with which you can instantly reverse the pattern. Or, probably better, have some other hams aim their antennas in the opposite direction so that they can catch the circumnavigating signals. 

Check it out: 

https://ei7gl.blogspot.com/2023/12/twice-around-globe-on-21-mhz-and.html

Two trips around is 80,000 km or about 50,000 miles!  That's quite a trip.  But how about 3 times around?  Or more? 

Thanks to John EI7GL and to Salvador EA5Y.  

A Marine's Home Workshop on Okinawa

 

Sergeant Malik Pugh recently won the Navy-Marine Corps Achievement Medal for stepping forward and 3D printing a part that was needed to put a satellite terminal back in operation.  That's was great, but even more interesting for us is the fact that Sergeant Pugh has a home electronics workshop in his place on family quarters on Okinawa.  See picture above.  

The workshop seems to be focused on RC cars, robots and drones, but there is clearly ham radio potential there.  This may be the first time since David Cowhig WA1LBP's tour on the island in the early 1990s that we see a workshop like this one.  David was 7J6CBQ and, in addition to his duties at the American Consulate at Naha, Okinawa, served as 73 Magazine's "Hambassdor" (I was the Hambassador to the Dominican Republic at the same time).  

Read about Sergeant Pugh here: 

https://www.stripes.com/branches/marine_corps/2023-12-25/mobile-satellite-communications-marine-japan-award-12465031.html  

A Nice Searchable Compilation of "Hot Iron" Issues

Tom K4ZAD writes: 

Bill,

This might make good copy for the SolderSmoke Daily News:

     https://www.w4npn.net/hot-iron-searchable-compilation/

Also it should be noted that starting with issue #122 W4NPN, Frank
Barnes is editing Hot Iron with help from the former editor G6NGR, Peter
Thornton. See: https://www.w4npn.net/hot-iron-directory/

I view the Daily News frequently, and also use the topics index on the
left when seeking more info on a subject. It often helps.

Tom    K4ZAD

https://www.w4npn.net/hot-iron-searchable-compilation/

https://www.w4npn.net/hot-iron-directory/

1000 Mile QSO with KC5U using Modified CB Rigs (video)

Eldon KC5U saw my blog posts about Jerry K5JC’s mods to the PLL02 CB rigs.

Here is the mod: http://www.jcoffman.net/WB5RUA/10_meter_AM_conversion_w_Photos.html

Eldon did the mod and we have been trying to make contact. We did so today. It was very cool. I was on my GE rig; Eldon was running a JC Penny! (See video above.) 1054 miles. Thanks Eldon. And thanks Jerry!