Monthly Archives: May 2015

Projects: Make your own Plasma-Arc Audio Speaker

Living in North Texas. I have been seeing plenty of electrical arcs lately, due to the unprecedented storms we have been having through the month of May.  A few of these arcs have been destructive — one of our sound system amps at our church started billowing out acrid smoke about the same time that we had a very close lightning strike, another local church took a direct hit a few weeks ago, and just the other day my friend Roger KE5YTA lost a radio power supply due to a very close strike.  Another friend, Don AE5DW in Louisiana took a direct strike two weeks ago and basically lost everything electronic in his house.

555 Timer IC (Wikimedia Commons photo)

Aside from the sights and smells that lightning and electrical arcs can create, they usually make a loud and obnoxious noise.  That’s why I was impressed when I saw the DIY Plasma Speaker on Instructables today.  Instructables member [tanner_tech] used a classic 555 Timer IC and a flyback transformer, high-voltage mosfet, and a fast diode from an old TV to make music.  Literally, you plug in any sound source and it creates (surprisingly) high quality audio from about a one inch high voltage electrical arc.  Visit the Instructable here and watch his YouTube video below — if you want to skip the technical stuff the music starts at about 3:10.  Then you just might want to go back and watch the technical stuff.

Published from DFW, Texas

Hamfest Review: Dayton Hamvention 2015

Some of the members of our Hamvention group - Joe K0NEB, Bill AD8BC, Bob KA9MDP, Kristen KB3OQV, Gregg N8ONW, and Brad W8PAL -- in the flea market at Hamvention 2015

Some of the members of our Hamvention group – Joe KØNEB, Bill AD8BC, Bob KA9MDP, Kristen KB3OQV, Gregg N8ONW, and Brad W8PAL — in the flea market at Hamvention 2015 (Photo Credit: N5KH (I think))

Another Hamvention has come and gone!  This was my 11th Dayton Hamvention, my first having been in 2005.  I decided after my first that this would be an annual thing for me and so far this goal has been met.  And so far I haven’t been disappointed.  This was also a special year for me because my Bob KA9MDP, my “Elmer” from 25 years ago, was able to attend, along with a few of my other friends from Dallas–Will N5KH, James N5BKL, Max N5BSA, Ken N2VIP, and Dhiren K5FPP.  I saw a bunch of other friends from Michigan and Indiana as well.  It was a great time and, as always, it went by quickly. Read more

Editorial: How To Sound Intelligent when Complaining about Hamvention

Hamvention 2015 officially ended this past Sunday at 1:00 PM EDT. (watch my blog for a hamfest review in a few days).  In my opinion, it was a great show.  There were only seven to nine (depending on who you ask) open vendor booths inside, the outdoor vendors and attendees looked to be about on par with last year.  There was no poop volcano, the stands didn’t collapse during the closing ceremonies, ceiling tiles didn’t fall on people (although some had fallen in the year since Hamvention 2014, so that was a distinct possibility). There was, of course, the unfortunate audio problems during the prize draw (the fault of which may have either been the DARA microphone/cable or the Hara Arena sound infrastructure.  I’d guess the latter.)  There were reports of some thefts from the flea market vendors but that happens every year.  Most aggravating were the reports of cars getting broken into that were parked in the big yard at the private residence across Basore Rd.  Anyway, come Sunday evening, the flood of complaints began (as they do every year) on the Hamvention Facebook page, followed by the rash of half-assed suggestions.  So I, your humble host, posted “AD8BC’s guide to successful and intelligent Hamvention complaining.”  Thought it should be posted here for easy reference: Read more