A fully diode-free signal chain can bring robust analog sensing and power functions into PCB and additive manufacturing. Brian Greenforest joins a DC- or audio-driven magnetic paramp front end with a two-core differential second-harmonic saturable-core downconverter.

Printed ferrite, amorphous ribbon laminates, plated windings, CNC scaffolds, and controlled annealing create a path that avoids clean-room semiconductor fabrication.

Build the Magnetic Front End as a Process

The design targets pump operation from 50 kilohertz to 1 megahertz. Core permeability, saturation, loss, winding count, symmetry, bias, pump amplitude, field annealing, and tuning determine conversion and gain.

A differential two-core structure extracts the second-harmonic response while rejecting common drive. Parametric or magnetic amplification raises weak signals before conversion.

Assemble the Sources and the Team

The research needs papers, patents, service manuals, technical reports, winding tables, core specifications, anneal schedules, printable ferrite formulations, and first-hand fabrication experience.

Magnetics labs, industrial historians, PCB process teams, and engineers with embedded-winding experience can contribute. The complete flow can open rugged, high-power, and radiation-hard hardware to builders outside semiconductor fabs.

Originally posted on LinkedIn

Brian Greenforest · Tuesday, April 14, 2026 at 8:19:04 PM PDT (2026-04-15 03:19:04 UTC)

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Magnetic Paramp plus Second‑Harmonic Saturable‑Core Downconverter — Seeking Experts and Sources I’m building a focused research thread on a fully diode‑free signal chain: magnetic paramp or mag‑amp front end driven by DC or audio, feeding a two‑core differential second‑harmonic saturable‑core downconverter, all manufacturable with PCB and additive techniques without clean rooms. This is about practical, reproducible fabrication routes using printed ferrite or amorphous ribbon laminates, plated windings, CNC scaffolds, and controlled anneal steps — not speculative theory. What I’m looking for Published papers, patents, service manuals, or technical reports that show combined paramp + saturable downconverter implementations or PCB/additive fabrication of high‑µ magnetic elements. Practical process notes on printable ferrite inks, anneal schedules, field annealing, or low‑loss thin‑film magnetic materials suitable for 50 kHz to 1 MHz pump operation. Historical sources from industrial or military archives that include winding counts, core specs, or tuning procedures for mag‑amps and second‑harmonic modulators. People or labs who have prototyped printed magnetics, embedded windings, or integrated magnetic devices on PCB substrates. Why this matters A working, reproducible fabrication flow would democratize robust, diode‑free analog power and sensing hardware and open new paths for rugged, high‑power, and radiation‑hard systems that do not rely on semiconductor fabs. If you have references, scanned manuals, patent numbers, lab notes, or first‑hand experience, please comment or DM. I’m compiling a short annotated bibliography and a prototype roadmap and I’m open to collaboration.