STATION NOTEBOOK / EM20VJ
The station centers on HF DX, VHF/UHF weak-signal operation and RF engineering. This page separates equipment on hand from antenna-system ideas under development. Descriptions are a planning snapshot, not a claim that every proposed configuration is installed or on the air.
Operating coverage
| Band group | Interests and system direction | Notes |
|---|---|---|
| 160–10 m HF | Wire antennas, DX, Field Day, practical vertical arrays | Emphasis on antenna efficiency and low-angle HF radiation |
| 50 MHz / 6 m | Sporadic-E, FT8, CW, SSB, meteor scatter | Directional Yagi development and path awareness |
| 144 & 222 MHz | Weak-signal terrestrial, meteor scatter and EME experiments | Low-noise receive chains; antenna height and horizon evaluation |
| 432 MHz | Terrestrial weak signal and contest operation | Directional Yagi and feed-system improvements |
| 902 & 1296 MHz | Long-path terrestrial and microwave experimentation | Phased antennas, power dividers and feed-loss control |
Radio and IF equipment
Equipment currently available or used in station planning includes the Icom IC-7300, Kenwood TS-2000, Yaesu FT-857D, Yaesu FT-817 and Xiegu X6100. Transverters provide access to several UHF/microwave bands. The FT-817 is particularly useful as a low-power IF platform for experimentation.
Antennas and tower projects
The current station project includes a directional 6-meter Yagi, long-boom 2-meter and 222 MHz designs, a 19-element Cushcraft antenna for 432 MHz, and Directive Systems antennas under consideration for 902 and 1296 MHz. Mounting arrangements, heights and stack spacing remain subject to installation and testing.
The installation uses a mixture of 7/8-inch and 1/2-inch hardline, flexible rotor-loop cable, coaxial RF relays and low-noise preamplifiers. At the higher UHF bands, small losses in connectors and jumpers deserve the same scrutiny as a major antenna change.
Low-noise reception
Antenna-side preamplification, a well-chosen noise figure and careful transmit isolation are priorities. A high-gain LNA cannot recover signal-to-noise ratio already lost ahead of it.
Transmit/receive protection
Sequencing and coaxial switching protect costly preamps and transverters. Isolation requirements rise with amplifier power and frequency.
Station pages and technical notes
Antenna Fundamentals
Wavelength, polarization and installation
Feed-Line Loss
Loss in dB, power budget and coax choices
Low-Noise RX Systems
LNA position, noise figure and gain
RF Relay Sequencing
PTT order, isolation and LNA protection
Power Dividers & Stacking
Amplitude, phase, spacing and verification
Terrestrial Path Planning
Radio horizon, terrain and atmospheric paths
VHF/UHF Propagation
Sporadic-E, meteors, tropo and EME
Common-Mode & RFI
Chokes, shielding and measurement
Rover Operations
Field layout, IF choices and antenna systems
K5QE Presentations
Marshall Williams: original papers and slide decks
Field Day
Portable station planning and operating
HF Contesting
CW, SSB and digital operating strategy
VHF & Above Contesting
50 MHz through microwave grids
Equipment, ratings and antenna details are engineering discussions and may change after measurement. Follow manufacturer data and RF safety requirements when constructing or operating equipment.