Deep-dive into every series in the Hood's Finds catalog. Every build name, every spec, every paragraph of why you want it on your bench.
From a beginner's first 50W QRP linear to a 1200W MOSFET monster to high-voltage prohibition-themed tube builds — the Hood's Finds amplifier series covers every topology, every power level, and every era of RF amplifier design. All 9 volumes are included in the Master Bundle.
The foundation volume. Ten HF linear amplifier builds that cover the entire landscape of solid-state design — from portable QRP to broadband 350W powerhouses. Every build includes a complete bill of materials, full SVG schematics, and interactive bias calculators. If you're building your first HF amp or your tenth, Vol 1 belongs on your bench.
The entry point. A clean, well-mannered 50-watt solid-state linear designed around readily available MOSFETs with a broadband matching network that covers 1.8–30MHz without switching. Perfect for the builder who wants a real linear — not a toy — without the complexity of a high-power design. Complete bias setup, impedance matching math, and a smoke-test procedure that actually tells you something.
Step up to 100 watts with a push-pull MOSFET design that handles SSB, CW, and AM without breaking a sweat. Broadband ferrite transformer design eliminates the tuning nightmare. Includes a thermal management guide — because a 100W amp that runs hot is a 100W amp that fails fast. The bias calculator walks you through quiescent current setup to the milliamp.
Five hundred watts is where things get serious — and so does the documentation. This build goes deep on power supply design, heatsink calculations, and protection circuitry. You'll understand exactly why the overcurrent protection is set where it is, what the SWR protection triggers on, and how to get reliable key-down operation without cooking the transistors.
The mobile challenge: 250 watts from a 12V vehicle power system. This build tackles DC-DC boosting, compact heatsink design, and high-current wiring — the three things that kill mobile amp builds before they ever go on the air. Includes a full wiring diagram for vehicle installation, fusing specifications, and notes on alternator noise rejection.
VHF is a different animal — parasitic oscillation will kill a transistor before you even key up if your layout isn't right. This build covers VHF-specific construction techniques: lead dress, ground plane requirements, microstrip matching, and stability testing. The layout diagram is detailed enough to follow without a PCB.
Field-portable 30W linear designed for battery operation. Efficiency is king here — this design squeezes Class AB operation down to a current draw that makes sense on a 20Ah battery pack. Complete enclosure fabrication notes, connector selection, and a battery life estimator calculator for common battery types.
A dual-MOSFET push-pull design that prioritizes linearity over brute power. The matched-pair approach reduces even-order harmonic distortion significantly. Includes a matching procedure for selecting transistor pairs from a batch and a harmonic output measurement guide.
The standout feature is the temperature-compensated active bias circuit — as the transistors heat up, the quiescent current automatically adjusts to maintain a consistent operating point. This is the difference between an amplifier that performs consistently across a 3-hour contest and one that drifts into thermal runaway an hour in.
A serious push-pull design optimized for continuous-duty SSB operation. Where most 300W builds are rated at intermittent power, this one is spec'd for sustained output. Includes a load line analysis for transistor selection, a transformer winding guide, and a complete ALC interface for use with modern transceivers.
The Vol 1 flagship. A 350-watt broadband amplifier that covers 1.8–30MHz with no band switching — flat response across the entire HF spectrum thanks to a carefully designed wideband matching network. Proper ferrite selection, precision wound transformers, gold-standard bias setup, and a protection system that handles anything you can throw at it. The complete reference build for Vol 1.
Vol 2 expands the arsenal in every direction — up to 6M VHF, out to mobile 12V operation, back into classic tube territory with the 6146B, and sideways into exotic topologies like Class E and SSB dynamic bias. Where Vol 1 is the foundation, Vol 2 is the expansion pack.
Six meters is the magic band — and this push-pull linear is built specifically for it. VHF-optimized layout, microstrip matching, and a stability analysis that explains exactly where the parasitics live and how to kill them before they kill your transistors. Covers the complete build from chassis metalwork to on-air testing with a dummy load.
Class E is theoretically 100% efficient — and while real-world results are closer to 85–90%, that's still dramatically better than Class AB for CW and digital modes. This build walks through the resonant switching theory, component selection mathematics, and the tuning procedure that makes Class E work.
A compact 80W mobile linear that fits in a project box and bolts under a dashboard. The DC wiring guide covers proper fusing, ground strapping, and RF bypass — the three things that separate a mobile installation that works from one that causes RFI nightmares.
The 2SC1969 is one of the most popular transistors in the CB and amateur radio world. This dual-device combo build shows how to harness a matched pair for push-pull operation, including source degeneration resistor selection that prevents current hogging and gate stopper values that keep the design stable at HF.
The 6146B is the tube that powered a generation of amateur transceivers — and it's still an excellent linear amplifier tube. This build covers high-voltage power supply design, cathode-driven grid bias, Pi-network output, and plate tuning procedure. Complete with a high-voltage safety checklist for working with 800V plate supplies. Old school. Proven. Absolutely worth building.
Negative feedback in an RF amplifier is counterintuitive — most builders avoid it — but when done correctly it dramatically improves linearity and reduces IMD. This build shows exactly how to implement resistive feedback without killing gain or creating instability, and includes IMD measurement procedures to verify the improvement is real.
Not everything needs 100 watts — sometimes you need ears, not muscle. This low-noise receive preamplifier is optimized for minimum noise figure and covers HF through VHF. PIN diode T/R switching integrates cleanly with any transceiver. Includes noise figure measurement procedure and a comparison of common low-noise transistors with actual measured data.
Class C is only legal for CW and FM — but within those modes it's brutally efficient. This 200W Class C build is optimized for contest CW operation where you're transmitting at near-100% duty cycle for hours. The efficiency advantage over Class AB at this duty cycle is significant. Complete with key shaping circuitry to keep the clicks off the band.
Most broadband HF amplifiers rely on wound ferrite transformers. This transformerless design uses transmission-line techniques to achieve wideband impedance transformation without a single turn of wire on a core. The fabrication guide makes building the transmission-line elements completely reproducible.
Dynamic bias tracks the envelope of an SSB signal and adjusts the quiescent current in real time — high bias during voice peaks for linearity, reduced bias during pauses for efficiency. The result is an amp that's both cleaner and cooler-running than a fixed-bias design. Complete with a voice-pattern test procedure for verifying the bias tracking is working correctly.
When you need legends, you come to Vol 3. Phase Linear 700 inspired. Hafler DH-500 classic. A 1200W MOSFET monster that has no business existing in a home workshop but does anyway. These ten builds are the ones that get named after where they're going.
Pure Class A operation — every transistor conducting on every cycle, all the time. The inefficiency is the point: Class A delivers the lowest possible distortion. This build is for the builder who wants the cleanest signal on the band regardless of power bill consequences. Massive heatsinking, precise bias current, and a linearity test procedure that will make you proud of what you built.
An updated take on the legendary Hiraga Class A topology using modern high-frequency MOSFETs for improved bandwidth and lower output impedance. The Hiraga circuit is famous for its subjective sonic quality — this build documents both the original topology and the modern modifications, with measurements to show what actually changed.
Bob Carver's Phase Linear 700 was famous for two things: enormous power and a tendency to self-destruct. This inspired design captures the high-current output stage topology while adding the protection circuitry the original famously lacked. The result is a 350W amplifier with Phase Linear character but without the Phase Linear drama.
Six hundred watts across HF and VHF from a single amplifier — the matching network design that makes this possible is the centerpiece of the build. Dual-band transformers, switchable Pi networks, and an interlock system that prevents operating into an open antenna.
The one they come for. Twelve hundred watts from a bank of paralleled MOSFETs — this build is the most technically demanding in Vol 3 and rewards the careful builder with a legitimate contest-grade amplifier. Current sharing between devices, balanced gate drive, thermal management for sustained 1200W output, and a power supply that doesn't apologize to the utility grid. Not for the timid. Completely documented.
The 572B is a rugged, widely available triode that makes a fantastic linear amplifier tube. This grounded-grid design is as close to foolproof as high-voltage amplifiers get — no tuned input required, simple plate circuit, and an input impedance that most transceivers can drive directly. Complete plate supply design, bandswitch construction, and a neutralization check procedure.
The Aragon 4004 was a benchmark amplifier of its era — high bias, robust output stage, overbuilt power supply. This replica builds on the original topology with modern components and better protection circuitry. Includes a side-by-side comparison of original and modern component choices and explains why each substitution was made.
Ultra-linear operation taps the output transformer screen grids to reduce distortion without sacrificing output power — a technique borrowed from high-fidelity audio and applied to RF. The result is a 500W amplifier with measured IMD numbers that will make you question why anyone builds anything else.
David Hafler's DH-500 defined a generation of amplifier design. DC coupling, high feedback, and a complementary output stage that was ahead of its time. This implementation preserves the essential circuit architecture while adding modern DC offset protection and SOA limiting. The circuit analysis section explains every design decision Hafler made and why it remains correct today.
SSB makes unique demands on a linear amplifier — the peak-to-average power ratio means the amp must handle full power peaks without compressing while remaining linear at average voice levels. This 500W design is optimized for exactly that behavior: fast bias recovery, adequate headroom for peaks, and ALC interface documentation for every common transceiver family. The Vol 3 closer.
30 complete amplifier builds — from a beginner's 50W QRP linear to a 1200W MOSFET monster — in one instant download. The full foundation of the Hood's Finds amplifier series.
The working builder's volume. Simple AB push-pull FET, classic 6AQ5 tube, 2SC1971 mobile linear, hybrid tube-FET combo, single-transistor CW QRP, broadband JFET RF preamp, Class C VHF booster, and more. These are the builds you actually construct in a weekend — complete, practical, and proven. No exotic parts. No unobtanium transformers. Just real amplifiers that real builders can build.
Ten Class-AB powerbuilders: MRF300 push-pull, BLF6G22 high-band booster, IRF540 budget AB, hybrid 6V6+IRF530/9530, 2N3866 Class E CB, 2SC1971 Class C CB, 2N3055 Class AB linear CB, IRF510 Class E CB, 2SC2879 push-pull Class AB, and BD139/BD140 push-pull. The transistor lineup reads like a who's-who of RF amplifier parts. Detailed bias setup and thermal management for every build.
The 11-meter dedicated volume. The Bare-Knuckle Class C AM Slammer. The Sideband Sniper. The GaN Gun-Slinger. The DSP Dynamo. Ten builds named for what they do and built for where they live. CB-optimized transistors, outlaw-appropriate topologies, and enough power to rattle windows three counties over. Educational purposes only. Complete design documentation for each build.
Essential homebrew, Class-AB elite designs, and 11-meter Outlaw Power — 30 builds covering every solid-state topology you'll ever need.
The glow-in-the-dark volume. Classic 6L6 Beast, 12AX7 Driver Amp, Compact 6BQ5 Linear, 2x6L6 Parallel CB Build, Sweep Tube Sleeper, Twin 6DQ6 Linear, Plate-Modulated Tube Amp, Dual-Band 10/11m with 6146s, Vintage Rebuild, and Mobile Tube Amp on Steroids. Ten tube builds from the practical to the legendary. Every build includes a high-voltage safety checklist, plate supply design, and the specific tuning procedure for that tube's characteristics.
Prohibition-themed high-voltage tube builds. The Bootlegger (4x6L6GC, 75–125W). The Speakeasy (2x811A, 175–250W). The Rumrunner (1x813, 150–225W). The Contraband (2x572B, 300–400W). The Hustler (1x3-500Z, 350–500W). The Syndicate (4x811A, 400–600W). The Kingpin (1x833A, 150–200W) — and more. Ten builds, 500V+ supplies, 10 CSS visual themes, animated interface, and a clock widget. The most advanced product in the catalog.
The Tickler. Swing King. The Splatterer. The Frequency Bandit. Echo Chamber. The Screamer. The Clipper Killer. The Harmonizer. RF Reactor. The Final Boss. Ten modulator-focused builds that live in the space between transmitter and amplifier. Audio processing, clipper circuits, frequency shaping, and modulation enhancement designs with dark/light/warm CSS themes and advanced JavaScript calculators.
Classic tube builds, 500V+ prohibition-era underground collection, and modulator-focused forbidden series. 30 builds. The premium end of the amplifier catalog.
The builders who shaped the CB and ham radio amplifier world deserve to be documented. Five tribute volumes — DaveMade, Fatboy, X-Force, Varmint XL, Hopper Built — each one a full 10-build series honoring a legend's style, topology, and contribution to the hobby. The Tribute Series is sold separately and is not included in the Master Bundle.
Big Red 1x2. Alley Pounder. Ghost Key Warrior. Redline Ghost 1x4. Driver Slammer. The 2x4 Street Heat. Ghost Box Lite. The 1x8 Mud Skipper. The Sled. The Redneck Rocket. Ten tribute builds inspired by the DaveMade style — HG-2879 transistors, street-named builds, and the kind of output stage simplicity that makes a design reliable for decades. Each build includes a reverential homage section and a Hood's Finds deviation callout wherever the design was updated for educational clarity. Not affiliated. Just honored.
Big Nasty 2x3 Combo. Fat Stack 4-Pill. Mobile Mayhem 1x4. Bench Buster 6-Pill. Driver Slam 1x2 Compact. Swamp Pounder 8-Pill. The Fat Brick 1x1. Twin Deck PowerHouse. 2x4 Pushin' Power. Competition Slammer Base. The Fatboy style is all about output stage robustness — more transistors, more thermal mass, more reliability. Ten tribute builds documenting that philosophy from a 1-pill compact to an 8-pill competition base station.
1x2 Storm Box. Ghost 2x2879. Street Talker 1x4. Long Chassis 2x4 Combo. Mobile Beast 4-Pill. Twin Driver Special. 6-Pill Stackdown. High Drive 8-Pill. The Alley Brawler. The Bench Load King. X-Force builds are characterized by their high-drive tolerance and robust output stages designed for real-world mobile and base station abuse. Ten tributes documenting the X-Force approach to maximizing performance from the HG-2879 transistor family.
The First Bleed. The Deep Bleed. The True Bleed. The Soviet Bleed. The Long Bleed. The Push-Pull Bleed. The Iron Bleed. The Bias Bleed. The Legacy Bleed. The Flagship Bleed. The Varmint XL is one of the most respected names in the CB amplifier world, and this ten-build tribute series documents the HG-2879-based circuit topology that made it legendary. Complete specs comparison tables showing original vs Hood's Finds implementation.
The Inlet Shrimper. The Lowcountry Hammer. The Straight 4. The Workbench 4. The SSB 2 Pill. The 6 Pill Base. The Low Drive 4. The 8 Pill Bruiser. The Carolina Crusher. The Flagship. South Carolina Lowcountry geography meets Hopper Built/Hopper Electronics circuit philosophy in ten tribute builds that honor one of the most distinctive builders in the hobby. Amber accent color system, HG-2879 specialist designs. If the original builder reads it, they feel honored.
DaveMade + Fatboy + X-Force in one collector's download. 30 tribute builds honoring three legends of the CB radio amplifier world. The complete first trilogy of Hood's Finds tribute documentation — the definitive reference for HG-2879-based amplifier topology as practiced by the builders who defined the genre.
Complete ham radio service manual collections for five major brands — Yaesu, Kenwood, Icom, Alinco, and Mixed. Schematics, alignment procedures, parts lists, and technical data for dozens of transceivers. Included in the Master Bundle.
The most complete Yaesu service manual collection available as a digital download. Twenty-one ZIP files covering dozens of Yaesu transceivers, receivers, and accessories — HF, VHF, UHF, handheld, and base stations. Every file includes original service schematics, alignment procedures, technical specifications, and parts list data. Instant download, works offline, yours forever.
Seventeen ZIP files of Kenwood ham radio service documentation covering transceivers, receivers, and accessories across multiple decades of production. Kenwood's engineering documentation is among the most detailed in the industry — circuit descriptions, alignment data, and schematics that actually explain what each stage is doing and why.
Ten ZIP files of Icom service documentation covering a wide range of transceivers, handheld radios, and accessories. Icom manuals are known for their clear schematic presentation and detailed alignment procedures — which makes them particularly valuable for the technician who needs to actually fix something rather than just replace the whole board.
Three ZIP files covering Alinco ham radio equipment — transceivers, handhelds, and accessories. Alinco built excellent value-oriented equipment with solid engineering documentation, and this collection preserves that documentation for the hobbyist community.
The catch-all collection — ham radio service documentation that doesn't fit neatly into the dedicated brand volumes. Multiple manufacturers, multiple eras, all organized and ready to reference. If you work on a variety of equipment and want a single download that extends your reference library beyond the big four brands, this is the volume for you.
51 interactive offline JavaScript calculators covering every calculation a radio builder needs. All 51 tools work with zero internet connection. Included in the Master Bundle.
The essential RF builder toolkit: impedance matching calculator, resonance frequency tool, SWR and power calculator, antenna cut-length calculator, capacitor and inductor value solver, transmission line calculator, and more. These are the calculations every builder does repeatedly — and every one of them has been turned into an interactive form you fill out and get an instant answer from.
Amplifier-focused calculations: bias point calculator, load line analysis tool, gain and efficiency calculator, power supply sizing tool, transformer ratio calculator, heat dissipation calculator, and more. These are the tools you reach for when you're designing — not just following someone else's schematic, but actually understanding why the values are what they are.
Advanced calculation tools: LC filter design calculator, coil winding tool with wire gauge compensation, enclosure volume and port tuning calculator, Ohm's law multi-solver, frequency conversion tool, wavelength calculator, and more. Vol 3 covers the calculations that come up less often but matter enormously when they do.
Every calculator Hood's Finds has built — 51 interactive offline tools in one instant download.
When you need a schematic now, not after a 45-minute internet search. Schematic libraries, CB radio guides, antenna builds, subwoofer enclosures, and repair references — all included in the Master Bundle.
The schematic reference library. 1,200+ homebrew electronics circuits spanning amplifiers, power supplies, RF circuits, audio gear, test equipment, and more. Organized and searchable. When you need to know how something was done — or need inspiration for how to do it differently — this collection has an answer.
A dedicated linear amplifier schematic collection — CB, ham, HF, VHF, single-transistor builds to multi-pill powerhouses. When you need to trace a circuit, understand a topology, or compare your build to a reference design, this collection is faster than searching the internet and more reliable than anything you'll find there.
The complete CB radio modification reference. Frequency expansion, clarifier modification, power output optimization, and performance enhancements for popular CB models. Every modification is documented with the specific procedure, the rationale for the change, and the expected result. Educational reference.
Complete Cobra CB radio service manual collection. Schematics, alignment procedures, and technical data for Cobra transceivers. When your Cobra needs service or you're trying to understand what makes it tick, this collection has the original documentation.
Twenty complete ham radio antenna builds — dipoles, verticals, yagis, loops, wire antennas, and specialty designs. Every build includes cut-length calculations, feedpoint impedance data, construction diagrams, and a mounting/installation guide. The antenna is the most important part of your station — this volume treats it that way.
Twenty CB radio antenna builds covering mobile and base configurations, ground planes, fiberglass whips, and specialty designs. 11-meter optimized with SWR tuning guidance and installation procedures for vehicle and fixed-station mounting.
Professional Skar Audio subwoofer enclosure designs — ported, sealed, and bandpass. Calculated internal volumes, port dimensions and tuning, bracing requirements, and construction procedures. Skar builds great drivers — this collection makes sure the box they go in is worthy of them.
Complete PS5 repair guide covering the failure modes that actually happen: HDMI port replacement, power supply service, fan control issues, and component-level diagnosis. Step-by-step with illustrated procedures. When the repair shop quotes you $200 and you have a soldering iron, this guide pays for itself on the first job.
Taramps car audio amplifier repair guide covering protection circuit diagnosis, MOSFET replacement, power supply repair, and common failure patterns. Taramps builds good amplifiers that can be repaired — this guide makes sure they are rather than getting thrown away over a $3 MOSFET.
All 9 linear amplifier build volumes — 90 builds from 50W QRP to 1200W monster — plus ham manuals, calculator suites, schematic libraries, CB guides, antenna builds, subwoofer enclosures, and repair references. One price. Offline forever. Tribute Series volumes are sold separately — browse them above.
Instant digital download · Works 100% offline · 30-day satisfaction guarantee · Educational use · Tribute Series sold separately
Want the Tribute Series too? The 5 Tribute volumes (DaveMade, Fatboy, X-Force, Varmint XL, Hopper Built) are sold separately at $9.99 each, or grab the Tribute Bundle Vol 1-2-3 for $14.99. Browse Tribute Volumes →