[Nashua Area Radio Society]

Hi Hamilton:

Thanks for the details.  I sent you a response email to the “.gmail.com” . address.  Did you get that material?  In short to your question, I am still using the “Lego Yagi” construction as described and demonstrated in 3 articles for the club’s website.  I have made minor changes that I described in the email.  My goal is to make quantitative measurements versus the lightbulb bridged receiver antenna, which is a good visual.

BTW, on Amazon I see telescoping antenna with F connectors…they are 75 ohm connectors.  Is that an issue?  I cobbled bnc connectors to my driven antenna elements, but it’s quite kludgy.  F connectors are definitely a better choice.

The christmas tree lights 1/4 wave antenna that I use to show the current profile along the elements is a good visual demo.  However, I have tried to tweak the Rogowski “pickup” coil to give a quantitative profile of the current without success.  I understand this circuit’s output drops significantly at high frequency.  So, is there a low-cost circuit that can achieve my goal?

Thanks & 73,  Dave  (N1RF)

[Nashua Area Radio Society]

Hamilton, Thanks for the pptx on combining the demo 2m yagi construct with 4nec2 software.  I’ll add it to my lecture as well.  BTW, I now feed the receiver antenna direct to an air-cool dummy load, convert signal to dc and display with a 1 in LCD display 5v meter.  I would appreciate your configuration.

73,  N1RF

Dave M.

[Nashua Area Radio Society]

Hi Craig,

I would like to participate as well.   Not sure where I’ll be, yet.  Please include me in any planning for this.

Jon T

AC1EV

[Nashua Area Radio Society]

Here is a link to the GSheet:

https://docs.google.com/spreadsheets/d/1Pvjoxj_MyKs2173SKNbU9tCq8IhNJ8cqlblSngoAsMY/edit?usp=sharing

This link will allow anyone with the link to COMMENT.  If you desire “EDIT” capabilities, please email Craig Bailey directly.

[Nashua Area Radio Society]

WOW!   This is a great response so far!  🙂

I am building a Google Doc Spreadsheet, and will be collecting all stations’ information as they come in.   I will post the link to the Gsheet as soon as I have a working doc.  Look for something by the end of the upcoming weekend.

Thank you all very much for the responses!  This is going to be great.

John Slater KB1EEU and I will setup a portable station and make a quick Mockumentary and post that as well, to give you all something to poke fun at, as you prepare your portable stations.

Sincerely, Craig

[Nashua Area Radio Society]

If you want an off-the-shelf solution, it would be a DC-DC converter module. They’re available from major electronics distributors such as Digi-Key and Mouser. They’re usually small rectangular modules with pins meant for a PC board, so you’d mount yours in your equipment with double-sided tape, and solder wires on.
The ripple at the switching frequency might be higher than you want, but an LC pi filter downstream can attenuate it to a millivolt peak-to-peak or less, at the cost of degraded transient response.
Caution: download the PDF data sheet before selecting the module you want, and read it carefully. Some DC-DC modules require external components for stability or ripple reduction. I would usually install a transient voltage suppressor across the input, to prevent resonant overcharging due to the inductance of the lead wires when plugging into a live voltage source.

Jack Carroll W1PK

[Nashua Area Radio Society]

As Ward Silver, N0AX, once wrote, “The best antenna is the one that is in the air.”  Any antenna “WORKS” (WithOut Real Knowledge by K0BG).  The Icom antenna will “work” and best with the tuner at its base.  It is very inefficient and gets worse when going lower in frequency.

A ground rod could work as a base, but does NOT help with efficiency.  It requires a counterpoise or radials to increase efficiency, possibly a challenge in your location due to permitting.  You’ll need the same for the flagpole antenna which is more efficient only because it is taller.  The more radials, especially if buried, the better.  Little is gained beyond 32.  Also, like the antenna, longer is better up to one-quarter wavelength at the lowest frequency used.

Neither antenna will be a good performer for NVIS work, up to a few hundred miles at 30m and below in frequency.  Since you can’t install wire antennas, I won’t get into the NVIS myth of lowering antennas to make them work better.

You’ll find great, helpful information at K9YC.com and W8JI.com on antennas and more.  You won’t find much useful help at places like QRZ.com and QTH.net.

Finally, the shorter and more shiny an antenna, the worse it will perform.  If it comes in a small package and is easy to setup, it probably won’t be very efficient.  But, like crows, hams like short (small) and shiny!

Anecdotes are useless.  Comparisons made simultaneously with other antennas using WSPRLite are meaningful.  I worked an Italian station on 20m SSB from NM with five Watts with a mobile screwdriver.  I didn’t remove my dipoles after that!

However, a short and shiny antenna is better than a dummy load or not antenna!

73, Bill, K8TE

[Nashua Area Radio Society]

Hello,

Curious if there was any progress with this? One of my friends and fellow ham just connected on his android phone without issue, but I am still getting a timeout error on my iPhone.

Thanks!

 

Mike

KC1MUU

[Nashua Area Radio Society]

Don’t know if its considered “low noise,” but I’m betting this one would be quieter than a wall-wart:

https://www.adafruit.com/product/1385

I’ve also got myself a bunch of smaller buck converters, but the link above is good for up to 3A output at 5V.

[Nashua Area Radio Society]

Hello Anita,

Suggestion/request; is it possible to list the question that was asked of all attendees on this post?

Thank you,

Ryan

[Author]

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