Search results
Query: roller coil
Links: 3 | Categories: 0
-
Amateur Radio 40m 20m 15m Half Wave Fan dipole antenna project with part list, pictures and drawing. Includes the option to expand the antenna to cover the 80 meters band
-
HAM-made engineering products supplies and produces coaxial relays, antenna switches, sequencers, roller inductors, variable capacitors, low noise preamplifiers, RF power rotary switches and coil bodies.
-
The PA0FRI Unbalanced/Balanced ATU is a home-built antenna tuner designed to efficiently match a W8JK 2-element beam antenna fed with a 450-ohm twin lead. Based on PA0FRI’s S-Match design, it optimizes energy transfer while maintaining balance, reducing losses, and ensuring proper radiation. The tuner uses a roller inductor, air variable capacitors, and a T200 iron powder coil, allowing fine-tuning across 14-50 MHz. Extensive lab tests confirm minimal attenuation and precise impedance matching, making it a reliable and efficient ATU for balanced antennas.