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Based on Motorola MRF454, schematics and component list

The MiniPA Linear Amplifier for HF page discusses the popularity of QRP for HF among ham radio operators, such as those using the Yaesu FT818 or low power SDR transceivers. It explores the use of cheap kits from eBay or Chinese suppliers to build a 70-100W SSB amplifier using IRF530 MOSFET transistors. The article provides a review of the MiniPA design, including its features, components, and assembly process. It also highlights the importance of using a heatsink and forced air cooling for optimal performance. This page is useful for hams looking to enhance their HF rig with a budget-friendly amplifier.

This page details my building of a 100 Watt Power Amplifier for the 432 MHz Band based on two Motorola MRF646 transistors taking inspiration by Carlo Gnaccarini VK3PY, formerly VK3BRZ

The Yaesu FTDX10 is presented as a compact HF/50MHz 100W SDR transceiver, employing a Hybrid SDR configuration that integrates Narrow Band SDR and Direct Sampling SDR. The Narrow Band SDR receiver features a Down Conversion design with a 9MHz first IF, incorporating 500Hz, 3kHz, and 12kHz crystal roofing filters. This architecture achieves a Reciprocal Mixing Dynamic Range (RMDR) of 116dB or more, a Blocking Dynamic Range (BDR) of 141dB or more, and a 3rd Order Intermodulation Dynamic Range (3rd IMDR) of 109dB or more in the 14MHz band at 2kHz separation. The local oscillator circuit utilizes a 250MHz High Resolution Direct Digital Synthesizer (HRDDS) method, contributing to a phase noise characteristic of -145dB or less in 14MHz at 2kHz separation. The transceiver incorporates a 5-inch Full-Color TFT display with touch-panel functionality, featuring a 3DSS (3-Dimensional Spectrum Stream) display for enhanced visualization. Front panel controls include an MPVD (Multi-Purpose VFO Outer Dial) for operational efficiency. Remote operation capabilities are supported with the optional SCU-LAN10 unit. Additional features include 15 separate band pass filters, IF DSP for QRM rejection, a high-quality final amplifier with RD70HUP2 MOSFETs, an aluminum heat sink with an 80mm cooling fan, and a high-speed automatic antenna tuner with 100-channel memory. The page also lists various accessories such as the SP-30 external speaker, XF-130CN 300Hz roofing filter, and several microphone models, alongside links to product brochures, operating manuals, and firmware updates.