2016 Activities

The October 21, 2016 meeting was held at Texas Instruments, 2900 Semiconductor Lane, Santa Clara

The speaker was Keith Snyder, KI6BDR, presenting a talk on “2 Meter and 160 Meter Mobile Computed Electric Fields inside a vehicle using “FEKO” compared to the FCC limits for RF exposure.

This talk showed the radiated far field pattern and near fields for a 2 Meter band (147 MHz) roof mounted antenna for varying power levels. The near fields were displayed outside and inside the vehicle compared to the FCC limit for safe RF Amateur Radio operation. A similar analysis was done for the 160 Meter band (1.9 MHz) antenna in the same location. The RF safety for these radios especially above 55 Watts push the limits and make you wonder if you are really safe operating your radio while you are in your car. The near fields were computed using a Patch based Method of Moments Program called FEKO. The 2 Meter results have been verified using an EMF meter as a sanity check. The EMF meter was demonstrated during the talk.

The September 6, 2016 meeting was held at Texas Instruments, 2900 Semiconductor Lane, Santa Clara

The speaker was Jeffrey Pawlan, WA6KBL, presenting a talk on “An easy to manufacture and very high performance microwave or millimeter wave horn antenna.”

In addition to antennas, Jeffrey began with a short review of using inexpensive copper water pipe as a very low loss medium to connect your radio to your antenna. He discussed modes, polarization, and the easy ways of working with circular waveguide taking the higher modes and polarization into consideration. Jeffrey designed ultra high performance feedhorns for the 10 GHz and 24 GHz bands. They will illuminate offset dishes or cassegrain reflectors very efficiently and eliminate the additional noise from behind and below the antenna. The designs were shown along with a comparison of the simulated and actual measured results. Some new research was shown with a broadband design for the 30-38 GHz millimeter wave band.