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Friday night at the Dayton DX Dinner I won in a drawing this wonderful antenna analyzer from Comet, the CAA-500.  It features a measurement range of 1.8 to 500 Mhz and displays SWR and impedance.  It is powered with five AA batteries or an external 8 to 16 volt DC supply can be used.

Thanks Comet and SouthWest Ohio DX Association!  This will really come in handy considering I’m in a new QTH and I’m in the process of putting up antennas and reassembling the radio artisan shack.  I couldn’t have asked for a more useful measurement tool.

(I am back home and I have several reports from Dayton to post in the next few days.  Stay on frequency…)

Anthony, K3NG, is a regular contributor to AmateurRadio.com.

In this episode, Martin M1MRB / W9ICQ is joined by Ed Durrant DD5LP, Martin Rothwell M0SGL and Chris Howard M0TCH to discuss the latest Amateur / Ham Radio news. Colin M6BOY rounds up the news in brief, and this episodes feature is  - Battery Technology

• 70 MHz Access for German Radio Hams
• RadCom Plus - New Amateur / Ham Radio Magazine Launched
• Radio to Smartphone revolution
• Reduced Bandwidth TVGB6SRF - Eastbourne Rally Special Event Station
• New North Texas Section Manager
• UK Amateur / Ham Radio Licence Statistics
• Amateur Radio Resources and Downloads

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

In this episode, Martin M1MRB / W9ICQ is joined by Ed Durrant DD5LP, Martin Rothwell M0SGL and Chris Howard M0TCH to discuss the latest Amateur / Ham Radio news. Colin M6BOY rounds up the news in brief, and this episodes feature is  - Battery Technology

• 70 MHz Access for German Radio Hams
• RadCom Plus - New Amateur / Ham Radio Magazine Launched
• Radio to Smartphone revolution
• Reduced Bandwidth TVGB6SRF - Eastbourne Rally Special Event Station
• New North Texas Section Manager
• UK Amateur / Ham Radio Licence Statistics
• Amateur Radio Resources and Downloads

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. For a thorough treatment of the topic, take a look at the National Institute of Standards and Technology (NIST) publication: Guide for the Use of the International System of Units (SI). A shorter and easier-to-read document was written by Charles Poynton: Writing SI units and symbols.

But more to the point, here are three common mistakes I often see occurring in ham radio literature:

1. Using mHz instead of MHz to indicate megahertz (one million hertz). Upper case M indicates mega, while lower case m indicates milli (one thousandth). In ham radio usage, we rarely speak of frequencies in mHz.  Note that I wrote mega with a lower case m even though the abbreviation has a upper case M. The unit of hertz is with a lower case h but when abbreviated as Hz, it should be upper case.
2. Using KHz or khz instead of kHz to indicate kilohertz (one thousand hertz). Lower case k should be used for kilo but upper case H is used for hertz. It is common to see upper case K used to indicate 1024 in digital systems.
3. Using M instead of m to indicate the unit of meter. The proper way to refer to the wavelength of the 144 MHz ham band is 2m, not 2M. Similarly, the abbreviation for kilometers is km, not kM or KM. The abbreviation for centimeter is cm.

Units that are based on a person’s name use an upper case letter in the abbreviation. For example, ampere, volt, watt and hertz are abbreviated as A, V, W and Hz respectively. When the unit is spelled out, it is left lower case (go figure).

While the world does keep on turning when we make these mistakes, accuracy and understanding is improved by proper usage. Did I miss any other common SI errors?

73, Bob K0NR

The post Three Common Mistakes When Using Metric Units appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to AmateurRadio.com and writes from Colorado, USA. Contact him at [email protected].

OK, I only tried this with WSPR and with low power, but at my old QTH I had a good deal of success using a small ferrite rod as a TX antenna on some HF bands. As long as the ferrite is not in saturation there is no good reason why it should not work. Most problems will occur if the antenna is driven with too much power.

See the link for more details. I have no idea about this ferrite rod’s properties but I think it was a fairly standard piece of ferrite rod and nothing too special at all.

Since being in hospital for 3.5 months and moving QTH I have not been able to find the ferrite rod to repeat the tests. My wife moved most of my stuff and it is probably deep in a box somewhere! At some point I guess it will just turn up.

See https://sites.google.com/site/g3xbmqrp3/antennas/ferrite_tx .

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.

Dayton Hamvention 2015 is over for me. I have a plane to catch Sunday morning so I made my final rounds through Hara Arena just before 5:00 pm. I will be back, good Lord willing and the creek don't rise. It was a good time and I now have lots of ideas of things to do in and around the shack.
Mike Crownover, AD5A, is a regular contributor to AmateurRadio.com and writes from Texas, USA. Contact him at [email protected].

Dayton Hamvention 2015 is over for me. I have a plane to catch Sunday morning so I made my final rounds through Hara Arena just before 5:00 pm. I will be back, good Lord willing and the creek don't rise. It was a good time and I now have lots of ideas of things to do in and around the shack.
Mike Crownover, AD5A, is a regular contributor to AmateurRadio.com and writes from Texas, USA. Contact him at [email protected].