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This article addresses the subject of obtaining the best signal transfer from an antenna to the typical 50-ohm receiver input over a wide frequency range, with emphasis on medium-wave (500 - 2000 kHz), encompassing the standard AM broadcast band and the 160-m amateur band.

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

A medium power End Fed Half Wave Antenna coupler, specifically tuned to the QRP frequency of 7030 kHz. Constructed from coil stock and capacitors, it achieves an impedance ratio of 64:1. The coupler has proven effective for power ranges from 2 to 100 Watts on the 40m band.

Demonstrates the conversion of an _Elecraft K2_ QRP HF transceiver to serve as a 2-meter Intermediate Frequency (IF) rig for microwave transverters, addressing the obsolescence of older _Yaesu FT-290R_ units. The project integrates a _DEMI 144-28DC_ transverter board, configured for a 28 MHz IF, and details the necessary modifications to the K2, including the installation of the K160M module for a separate receive-only antenna input and the KSB2 SSB module for voice operation. The modified K2 provides a stable 1-watt output for the 2m IF, utilizing the QRP antenna jack for transmit and the K160M input for receive, with a custom PTT control circuit. The article outlines the physical integration and electrical interfacing, including the design of an internal attenuator for the 28 MHz IF output and a control circuit for the 144 MHz interface. It also covers the construction of a medium power amplifier using an _MGA-31389 MMIC_ to boost the 2m output to 100 mW, matching the original FT-290R performance. Performance measurements for the amplifier, including output power versus input power and gain versus frequency, are presented. The project culminates in a fully integrated solution, with schematics and photos illustrating the internal wiring and external connectors. The modified K2, dubbed the "K290R," was successfully deployed in the 2017 _ARRL 10 GHz and Up Contest_ with a _Kuhne 10 GHz_ transverter, demonstrating reliable operation for CW and SSB modes.