Showing posts from June, 2011

Field Day 2011

  Field Day 2011 Filed in Contests on Jun.28, 2011 Results for Field Day 2011: For Field Day 2011, I had some slightly different goals than in the past: Incorporate CW contacts into the mix Incorporate PSK/Digital Contacts into the mix Concentrate on working maximum number of stations, regardless of sections worked Operate Off of Battery Power, to provide relief from generator occasionally Get 43′ Dipole working on 160 – 10 meters I accomplished all of these goals, with the exception of #2. While I had the digital interface hooked up (I believe correctly), I was never able to get anyone to talk with me on PSK-31 prior to Field Day Operations starting. So I gave up on that aspect. I’ll debug the operational/technical problem at home. I don’t know if better propagation resulted in more sections worked, or better antennas (43′ vertical for most contacts this year), or just the fact that I was calling everyone I heard.   It’s strange that I couldn’t work some of the 7th call

43′ Vertical Final Tuning

  43′ Vertical Final Tuning Filed in Antennas on Jun.28, 2011 After acquiring an Antenna Analyzer (MFJ-269B), I set the matching network on the bench and began playing with it.  I had a theory that I could simulate the antenna load at various frequencies by placing a capacitor in series with a resistor of various values for the different frequencies.  Then by attaching that to the matching network where the antenna would attach, I could pre-tune the matching network without having to erect the antenna in my back yard. After some research on the AD5X site (What a great resource), I found that a vertical has a pretty consistant capacitance to ground that is determined by the formula: Cpf = 3.5pf/ft X Actual length So for a 43 foot vertical, it should have a capacitance of about (3.5 x 43) = 150.5 pf . Now that I knew this, I could put a 150 pf capacitor in series with a resistor that susbstitutes for the radiation resistance of the antenna at the frequencies of interes

Tilt-Over Support for 43′ Vertical

  Tilt-Over Support for 43′ Vertical Filed in Antennas on Jun.28, 2011 I took the two grandsons up to the Ranch in mid-June to help with construction of the 43′ vertical tilt-over support. The idea is to be able to easily tilt the vertical down to a “stowed” position before I leave for an extended period of time. It shouldn’t hurt to have that capability in case of thunderstorms, as well. Basically, we modified the 4×4 post that the vertical was attached to last year. We now have the vertical attached to a 2×4 pressure treated 8′ board. This board is hinged near the top of the 4×4, so when the vertical is tilted down, it is still above the heads of most of the cattle around the ranch.   The bottom of the 2×4 also has a bolt that goes through the 4×4 to hold it in an upright position. To get to this point, we had to dig two new holes and plant 2 new 4×4 posts to support the vertical in the stowed position.       Migrated Comments: 2 Responses to “Tilt-Over Support for 43′ Verti