Saturday, April 17, 2010

Skywarn Communications Test Today

We participated in the Skywarn Communications Test today along with the National Weather Service in Charleston.  This was a South Carolina, SE North Carolina, and Coastal Georgia exercise.  NWS Charleston is responsible for 12 of our Georgia Counties here along the coast.  Bobby-W4KSD kicked off the net from the NWS Charleston station WX4CHS.  Several of us were able to check into the SC linked repeater system.  I kicked off a net on the Chatham County ARES frequency of 146.970 to pick up stations in Chatham, Effingham, Bryan, and Liberty counties.  Dan-KF4MND ran a net on the 147.105 to pull in stations in Long and Bulloch counties.  David-KC4MKD called for checkins on the Georgia ARES HF frequency of 3.975.  We had a total of about 20 checkins and I relayed them all into Bobby at WX4CHS.  It was a successful exercise in preparation for tornado and hurricane season.

Arecibo Moon Bounce Continued

I Didn't hear anything on the moon bounce from the Arecibo station today. They got the amplifier fixed and were running 350w. Kevin-KW4B did hear them briefly on his Arrow antenna right when they switched over to CW.  He distinctly heard KP4.  They made over 100 contacts on SSB and CW. Seems I need a yagi with more elements and a pre-amp. It's still been fun to follow....K4GTM




Friday, April 16, 2010

Arecibo Moon Bounce Update

Kevin-KW4B and I attemped to hear the moon bounce signal from the Arecibo station today with no luck.  Turns out they had an amplifier failure and are in the process of repairing it now.  Should be ready for tomorrow.  They did make almost 100 contacts using low power (50 watts) so that's good.  They are streaming a live feed from the event at http://www.ustream.tv/channel/kp4ao-eme.

Tomorrow's window is from 1340 to 1620 local.  We'll be meeting up at our club station tomorrow at the Southside Fire Station to give it another try.

Thursday, April 15, 2010

Homebrew 70cm Yagi

I built a simple six element 70cm Yagi antenna today in hopes of hearing some of the mounbounce signals from the Arecibo radio telescope in Puerto Rico on Apr 16, 17, 18.  Found a simple plan online and I used a piece of scrap wood for a boom and some 12 gauge copper wire that I had left over from another project for the elements.  I trimmed down a piece of RG-58 with a BNC connector for the feedline and soldered it to the driven element.  I then secured my Yaesu VX-7R to the boom with a tie strap.  Connected the feedline to the radio then went outside to give it a test.  I backed the power on the handheld down to low power which I think is half a watt (500mw) and pointed in the direction of the 442.700 repeater.  I brought the repeater up with no problem and had the receive at full scale.  I decided to test the directional characteristics of the antenna by turning it away from the repeater and sure enough just the slightest deviation and I lost the repeater.  That's exactly what I was looking for, a very narrow and directional beam.  We'll see how I make out over the next few days.  Total time of construction and testing was about 30 minutes.

Moonbounce Info

Wednesday, April 14, 2010

April 14, 2010 B-17 Radio Work


We had a very successful day at the Mighty Eighth Air Force Museum as we continued our work on the BC-348 receiver for the B-17 project.  Carroll-WX4Y and Guy-K4GTM arrived at 2:00pm to get started with the days work.  Over the last few weeks we have assessed the condition of the radio, tested the tubes, resisters, and capacitors, taken apart, serviced and tested the dynamotor which delivers the power to the radio, put the dynamotor back in and tested the the radio circuits, etc.  Todays primary task was to replace one bad tube (the audio amplifier) and to align the various IF stages.  Once we put the new tube in and powered things up, we connected a signal generator/spectrum analyzer to the antenna input and inputed a test tone on various frequencies to see if the receiver could hear it.  Not only did the reciever hear the test tone, it was spot on frequency everywhere we tested it!  Wow!  Don't really need to do much of an alignment afterall.  This is an outstanding radio for being 65 years old.  Only thing to do next was to hook up an antenna and see if we could pick anything up.  We moved the radio outside to be out of the metal building and away from all of the RF interference inside.  We needed an antenna so I found a spool of wire that was perfect.  We ran the long wire "antenna" out about 200 feet or so across the lawn and over a short tree to give it some elevation (10 feet off the ground at it's highest).  We connected the wire to the antenna posts on the radio and wham, we were picking up a shortwave broadcast station on about 6.100 MHz!  Was probably Radio Havana judging by the signal strength and frequency.  We tuned around and picked up several other shortwave stations as well as some morse code and single sideband voice on one of the HAM bands.  I can't tell you how excited Carroll and I were to the hear this thing come to life.  We are so fortunate to be able to participate in this restoration project.  Plenty more work to be done but this was a major accomplishment today.

2010 Georgia QSO Party

Had a great time over the weekend as our club competed in the Georgia QSO Party from our station at the SSFD.  Folks started showing up around 0800 and we got to work getting the station ready and hoisting up a couple of dipoles for 40m and 80m.  Had everything tested and ready to go by the contest start time of 1400.  We even had time to do a little training of some of our new HAMs and let them get on the air for the first time.  We had many operators come and go throughout the day.  Several of us stayed and operated all the way till midnight.  Lot's of fun. 

Steve-K4SDJ and Kevin-KW4B showed up around 0800 on Sunday ready to kick things back off at 1000. We operated all through the day on Sunday until the contest end time of 2000. It was a good contest as our club multi-operator station racked up around 250 contacts and Guy-K4GTM's station got close to 100 contacts. Many other club members operating from home during the contest as well.