Enhancing the Collins 180S-1 Antenna Tuner: Complementary Balun Designs Products for Modern HF Operation Technical White Paper — Collins S-Line Restoration & Integration Series 📝 VK6ADA Technical Papers 📅 March 2026 🔌 HF Antenna Systems ⚡ 1 kW Class Abstract.…
Collins 75S-3 — BFO Sideband Tolerance Reduction: Design Options Engineering Design Study — Collins S-Line Series Collins 75S-3 ReceiverBFO Sideband Tolerance Reduction Design Options to Reduce USB / LSB Dial Offset — Component Changes, Circuit Modifications, and Modern Replacement Strategies…
Collins 75S-3 Receiver – Known Issue: USB/LSB BFO Dial Offset Known Issue — Collins S-Line Series Collins 75S-3 ReceiverUSB / LSB BFO Dial Offset Tunable BFO “Zero” Position Differs Between Sidebands — Normal Tolerance Behaviour vs. Alignment Fault Equipment: Collins…
Single-Band Loss: Symptom Analysis, Root Cause Diagnosis & Troubleshooting Collins Radio · Technical Reference Series Collins 32S-3 Transmitter Single-Band Loss: Symptom Analysis, Root Cause Diagnosis & Troubleshooting 80 METRES VFO INJECTION 1ST MIXER BAND SWITCH Reported Case Summary All three…
Antenna Engineering Guide · Collins S-Line · Balun Designs Multiband HF Loop Antennas with the Collins 180S-1 Tuner, Balun Designs Model 4114 and Model 1115d Impedance Transformation, Common-Mode Suppression & Practical Installation for 160–10 Metre Operation by Mike Peace VK6ADA…
Collins KWM-2A Transceiver RFI Mitigation & Receiver Noise Reduction Ferrite Cores, Inductors, Filtering & Grounding Modifications for the Modern Noise Environment Mike Peace VK6ADA • r-390a.net Administrator 1. Executive Summary The Collins KWM-2A is a double-conversion SSB/CW transceiver covering 3.4–30.0 MHz,…
Collins 312B-3 Speaker Cabinet Bluetooth Speaker Conversion Dual-Mode DC / Li-Ion Battery Power · Bluetooth 5.0 aptX HD · Dayton Audio KAB-250v4 + LBB-5Sv2 · Ferrite RFI Suppression Mike Peace VK6ADA · r-390a.net Administrator · March 2026 1. Project Overview…
Collins 516F-2 Speaker Cabinet Bluetooth Speaker Conversion Dual-Mode AC / Li-Ion Battery Power · Bluetooth 5.0 aptX HD · Dayton Audio KAB-250v4 + LBB-5Sv2 · Ferrite RFI Suppression Mike Peace VK6ADA · r-390a.net Administrator · March 2026 1. Project Overview…
Collins MP-1 Power SupplyComplete Restoration Kit For the S-Line · KWM-2 · KWM-2A | Includes RFI Mitigation Ferrite Package 47 Components 100% USA Sourcing Ships from Missouri 6Kit Sections 47Components 6US Vendors 4Ferrite Types The Collins MP-1 mobile power supply…
Collins 136B-2 Noise Blanker Engineering Changes & Circuit Modifications Reference Collins 136B-2 Noise Blanker Engineering Changes & Circuit Modification Reference Covering factory-issued changes, community-developed improvements, alignment notes, antenna adaptation, and advanced modifications for contemporary fixed-station use. 1. Background & Design…
Engineering Reference Document Collins 516F-2 Power Supply RFI Analysis & Mitigation Engineering Guide Noise Floor Reduction Strategies for Collins S-Line, KWM-2, and KWM-2A HF Station Installations Prepared by Mike Peace VK6ADA | r-390a.net Administrator | Document Revision 2.0 — February…
Vintage Hammarlund · Restoration Guide Hammarlund SP-600 JX-16 Complete Restoration, Alignment & RFI Mitigation Guide Mike Peace VK6ADA · r-390a.net Administrator Parameter Specification Frequency Coverage 0.54 – 54 MHz in 6 bands Conversion Double conversion (above 7 MHz); single below…
Mission RGO ONE · Technical Guide RGO ONE HF Transceiver RFI Mitigation, Receiver Noise Reduction & Signal-to-Noise Ratio Improvement Guide Mike Peace VK6ADA · r-390a.net Administrator Field Detail Author Mike Peace, VK6ADA Website vk6ada.com.au Resource r-390a.net Transceiver Mission RGO ONE…
Collins 32S-1 Transmitter
Boatanchor Legends — A Tribute Series Matt Parkinson is one of the credited contributors to “The 21st Century R-390A/URR Technical Reference” — the Y2K Manual — the document that transformed the R-390A from an equipment type served by scattered, aging…
HSN Founding Editor & R-390A Historian • Gulfport, Mississippi The Founding Editor Les Locklear of Gulfport, Mississippi is one of the foundational figures of the modern R-390A community. As the original editor of the Hollow State Newsletter, he shepherded the…
K1LKY — R-390 Restoration Authority & NIST Engineer The Professional Engineer Roy Morgan, K1LKY (of Western Massachusetts, formerly at the National Institute of Standards and Technology), brought professional-grade engineering discipline to the R-390 community. His restoration guidelines for the R-390…
AGC Engineer & Circuit Analyst Ending the Moment of Silence David Wise is one of the most technically rigorous contributors in the R-390A community’s history. His signature achievement is the landmark document “R-390/R-390A AGC — Ending The Moment Of Silence,”…
N5OFF — R-390A Production Historian & Document Preservationist The Historian Tom Marcotte, N5OFF, is one of the most important historical researchers in the R-390 community. For years, he has been diligently amassing production data — contract numbers, manufacturers, quantities, and…
W5OR — R-390 List Manager & R-389 VLF Receiver Authority The List Manager Don Reaves, W5OR, served as the manager of the R-390 mailing list — the primary online gathering place for the R-390 community for many years. In this…
The Collins R-390A is arguably the finest tube-era military HF receiver ever built — but it was designed in the early 1950s for AM and CW reception. As amateur and military communications transitioned to single-sideband (SSB), several aftermarket solutions emerged…
R-390A Aftermarket SSB Adapters: A Comparison Guide R-390A Aftermarket SSB Adapters: A Comparison Guide Mike Peace · March 9, 2026 · Amateur Radio, R-390A.NET The Collins R-390A is arguably the finest tube-era military HF receiver ever built — but it…
The Boatanchor Legends series honors the individuals who built, preserved, and shared the technical knowledge that keeps the R-390A and its sister receivers alive. From the editors of the Y2K Manual to the archivists who saved disappearing documentation, from the…
Boatanchor Legends: Barry Hauser — Y2K Manual Co-Editor & Community Voice Boatanchor Legends — A Tribute Series Barry Hauser New York Y2K Manual Co-Editor • Reflector Voice • Community Historian Barry Hauser brought two rare qualities to the R-390A community…
Boatanchor Legends: DW Holtman, WB7SSN — Y2K Manual Technical Illustrator Boatanchor Legends — A Tribute Series DW Holtman, WB7SSN Y2K Manual Contributor Technical Illustrator • Digital Draftsman DW Holtman brought a draftsman’s precision to the R-390A community’s most important document.…
Boatanchor Legends: Gary Gitzen — Y2K Manual Contributor Boatanchor Legends — A Tribute Series Gary Gitzen Y2K Manual Contributor Technical Knowledge • Community Expertise Gary Gitzen is one of the credited contributors to “The 21st Century R-390A/URR Technical Reference” —…
Boatanchor Legends: Tom Norris — Y2K Manual Contributor Boatanchor Legends — A Tribute Series Tom Norris Y2K Manual Contributor Technical Expertise • Community Knowledge Tom Norris is one of the credited contributors to “The 21st Century R-390A/URR Technical Reference” —…
Boatanchor Legends: Scott Seickel — Y2K Manual Contributor & Reflector Participant Boatanchor Legends — A Tribute Series Scott Seickel Y2K Manual Contributor R-390 Reflector Contributor • Technical Knowledge Sharer Scott Seickel holds a distinctive place in the R-390A community: he…
Wei-i Li The Archivist Every technical community generates far more knowledge than it manages to preserve. Conversations happen, problems are solved, solutions are shared — and then the thread scrolls off the page and the answer that took three experts…
Clemens Stubbe Østergaard The Scholar at the Receiver The R-390A community has always attracted serious people — engineers, technicians, former military operators, and dedicated amateurs who approach the receiver with the same rigour they bring to their professional lives. Clemens…
Dr. Gerald N. Johnson — KE0KI The Engineer in the Room Most online technical communities have enthusiasts, experienced hobbyists, and the occasional retired technician. Very few have a licensed Professional Engineer with a Ph.D. in electrical engineering who shows up…
Electric Radio Magazine — Barry Wiseman N6CSW & Ray Osterwald N0DMS The Publication That Gave the Community a Voice Every technical community needs somewhere to put its knowledge down in writing — somewhere permanent, indexed, and reproducible. For the R-390A…
Jan Skirrow, VE7DJX British Columbia, Canada Circuit Designer · Kit Builder · Community Innovator Jan Skirrow, VE7DJX, is one of the R-390A community’s most enduring innovators — a designer who translated the theoretical improvements that the reflector’s technical community had…
David Medley United States Master Restorer · R-390 Family Specialist David Medley was one of the most skilled hands-on restorers of R-390 family receivers in the community’s history. A Medley restoration was considered a mark of quality — a receiver…
Roger Ruszkowski, KC6TRU United States Ex-Military Operator · Technical Authority · Reflector Legend Roger Ruszkowski, KC6TRU, was among the most respected technical voices on the R-390 reflector during the mailing list’s most active years in the early-to-mid 2000s. His combination…
Peter Graves Silent Key New Jersey, United States Custodian of the Fowler R-390A, Serial Number 1 · Silent Key, 2023 Peter Graves held a distinction that is unique in the history of the R-390A: he was the owner of the…
Wally Chambers – SK United States R-390 Manufacturer Historian · Silent Key Wally Chambers was the community’s foremost historian of the R-390 family’s manufacturing history. In a community where most expertise is focused on circuit operation, alignment technique, or restoration…
Al Tirevold, WA0HQQ Silent Key United States Website Administrator · Community Archivist · Silent Key, July 2021 Al Tirevold, WA0HQQ, is one of the most quietly indispensable figures in the modern history of the R-390A community. For years he supported…
Bob Thomas, VE3TOU Godfrey, Ontario, Canada Founder, Treetop Circuits · SSB Adapter Designer · Licensed Amateur Since 1958 Bob Thomas, VE3TOU, is the designer and founder of Treetop Circuits — the small Ontario cottage operation that for thirteen years produced…
Boatanchor Legends: Edward Kujawski — The BAMA Archive Boatanchor Legends — A Tribute Series Edward Kujawski The Boat Anchor Manual Archive Keeper of the Manuals — bama.edebris.com Every restoration begins with a manual. Before the first capacitor is replaced, before…
Boatanchor Legends: Ted Robinson, K1QAR — Engineer, Restorer, Innovator Boatanchor Legends — A Tribute Series Ted Robinson, K1QAR Fairhaven, Massachusetts Yale Engineer • Collins Restorer • Magnetic Loop Pioneer Ted Robinson brings a rare combination to the R-390A community: a…
Boatanchor Legends: Paolo — La Famiglia 390 Boatanchor Legends — A Tribute Series Paolo Italy La Famiglia 390 — The Complete R-390 Family Reference Paolo brought an international perspective and a scholar’s thoroughness to the R-390 community with “La Famiglia…
Boatanchor Legends: Jim Thompson, W4THU — St. Juliens Creek Eyewitness Boatanchor Legends — A Tribute Series Jim Thompson, W4THU The Radio Works — Portsmouth, Virginia St. Juliens Creek Eyewitness Jim Thompson’s eyewitness account of the St. Juliens Creek Annex surplus…
Boatanchor Legends: Don Heywood, WC4G — R-390 Non-A Specialist Boatanchor Legends — A Tribute Series Don Heywood, WC4G South Carolina R-390 Non-A Specialist & Restorer Don Heywood earned his reputation in the R-390 community through deep, practical expertise with the…
Boatanchor Legends: Chuck Teeters, W4MEW — Nomenclature Tags & Tropicon Boatanchor Legends — A Tribute Series Chuck Teeters, W4MEW Fort Monmouth Nomenclature Tags Historian & R-725/URR Researcher Chuck Teeters brought a historian’s rigor to the R-390A community through two distinctive…
Boatanchor Legends: Richard Biddle — Gear Train Disassembly Guide Boatanchor Legends — A Tribute Series Richard Biddle Gear Train Documentation Making the Intimidating Accessible The gear train of the R-390A is one of the most mechanically complex assemblies in any…
Boatanchor Legends: Cecil Acuff, K5DL Boatanchor Legends — A Tribute Series Cecil Acuff, K5DL Gulfport, Mississippi Long-time Community Contributor Cecil Acuff was a fixture on the R-390 reflector mailing list for more than two decades, contributing practical wisdom on both…
Boatanchor Legends: Randy Stout — R-390A Spotter’s Guide Boatanchor Legends — A Tribute Series Randy Stout R-390A Spotter’s Guide Identification Reference Pioneer Before the internet made visual identification of R-390A manufacturer variants relatively straightforward, collectors buying at hamfests, surplus sales,…
Boatanchor Legends: Floyd Soo, W8RO — HI-RES Communications Video Archive Boatanchor Legends — A Tribute Series Floyd Soo, W8RO HI-RES Communications Bringing Restoration to Video Floyd Soo recognized something that the R-390A community needed before most of its members realized…
Boatanchor Legends — A Tribute Series Larry Haney has been a steadying presence on the R-390 reflector mailing list for decades, contributing practical wisdom on R-390A alignment, troubleshooting, and restoration with the authority of someone who has spent a lifetime…