VE6AB Mobile Ops
The Field Operation
Knowing that I needed to make a modification to how my shop built tri-band log-periodic antenna (2m, 1.25m, 70cm) mounts on the Max Gains System mast assembly, I recently spent time in my shop making the necessary modifications.
Now the modification required wasn't made to the antenna directly, but to the ball mount that is utilized when switching the antenna between the horizontal and vertical positions on the mast.
The solidity of the ball-mount that kept the antenna fastened to the mast, was being compromised, especially with the starting and stopping of the wireless keyfob controlled 12 volt rotator located beneath the mast assembly.
I originally had built the ball-mount to accomplish the switching over from vertical to horizontal, and although it worked reasonably well as built, the mount proved to be somewhat on the fragile side in the area of locking the ball down.
So with time spent in my shop, I came up with a more robust ball mount that has proven to be exactly what was required to keep the antenna firmly secured in either the horizontal or vertical position on the mast.
With the contest still a week away, I was in no particular hurry to proof my equipment, knowing that other than the re-constructed ball-mount, everything else was good to go.
Now having said that, an email arrived in my mailbox informing me tha there was to be a SOTA three-way summit-to-summit activation on Sunday June 4th starting at about 11:00am local time.
The peaks would be Missing Link Mountain, in the Sheep River Drainage west of Turner Valley, activated by Ian VE6IXD.
Square Butte west of Millarville, activated by Rich, VE6LCE
And IF39, an otherwise unnamed hill just south of McLean Hill, SW of Bragg Creek activated by Lewis VE6LEW
They would be using 2m FM vertically polarized antennas on 146.52, as well as 2m SSB on 144.2.
I realized this would be the perfect opportunity for me to test the modifications that I had made to my antenna and mount. On this day I was operating with my Yaesu FT-897ND that I had removed from its normal position, as part of the manpack featured in my 'VE6AB Portable Gallery', and had it sitting on the console beside my radio stack mounted in my mobile.
Although I could have also operated on 6 meters with the 6 meter halo connected to the FT-897ND, on this day I chose to operate on 6 meters with the Kenwood TS-480HX mounted in the radio-stack of my mobile.
Long story short, with everything set up as seen in the photo, and with the all the guys having hiked in and set up on their respective peaks located along the eastern slope of the Rockies southwest of my location northeast of Calgary, I was able to easily hear and work all of the guys using the 2 meter segment of my tri-band log-periodic.
The new ball-mount that I built and installed for positioning the tri-band log-periodic, performed to the standards that I originally wanted it to,
You may have noticed in the photo that I have the log-periodic positioned in the vertical polarization position.
This was because all the stations duing SOTA activations were using vertically polarized antennas.
When the ARRL Field Day weekend comes around on June 24-25, I will add my 10-20 meter inverted U horizontal dipole to the top section of the mast, the 3 top mast sections nested within the segment supporting the log-periodic in this photo.
My mobile has three 12 volt batteries mounted within, two in the engine bay, and one mounted in the cargo bay, the one mounted in the cargo bay, connected to the FT-897ND on this day.
The solar panels residing on the top of the cargo bay along with a charge controller, are connected to the battery mounted in the cargo bay.
The invertor generator seen sitting on the ground has a 12 volt intelligent charger plugged in to the panel on the generator, and in turn this battery charger with its 7.5 amp output is connected to the 78 Ah battery mounted in the battery box visible in the cargo bay.
Although charging the cargo bay battery was not required for the short time that I was operating on this day, I wanted to make sure everything was good to go for the VHF contest coming up, as well as for Field Day looming on the horizon.
Click on the photo for a closer look.....
Here is a closer look at the mount used for positioning the antenna in the vertical or horizontal position.....
http://www.jerryclement.ca/MachineShop/Antenna-Werks/i-PqxCpzB
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