KWM-2A Clinic: When the Preselector Peak and Grid Drive Peak Don’t Agree A good question landed on the reflector recently from Lenny, WB6QAZ, who is bringing a round-emblem KWM-2A back to life. The radio is working well on both receive…
Yaesu FT-101E — Parts Substitution & Sourcing Reference Common failure points, modern equivalents and procurement notes for the FT-101E hybrid transceiver (12BY7A driver + 2×6JS6C finals; otherwise solid-state, dual conversion: 5 MHz 1st IF, 9 MHz VFO, 3.18 MHz 2nd IF). 20 Tracked Parts 7…
VK6ADA Technical Reference · Boatanchor Files The Collins R‑389, R‑390 & R‑390A Development, deployment, and a practical operator’s guide to the finest HF receivers of the vacuum-tube era — written for amateur radio operators and shortwave listeners, fact-checked against the…
Boatanchor Legends — A Tribute Series Carol Maher, W4CLM The keeper of the Fox Tango flame — who took a dormant newsletter club and built it into the definitive online home for Yaesu owners the world over. Some legends of…
Boatanchor Legends — A Tribute Series Milton Lowens, WA2AOQ · N4ML The retired engineer who answered one radio’s design flaw by founding the most influential users group in amateur radio history — and proved that one man, one typewriter, and…
Boatanchor Legends · Tribute No. 47 Silent Key Glen E. Zook, K9STH First Article at Seventeen, and Six Decades Without Stopping Silent Key 22 July 2020, Richardson, Texas First Licensed as a teenager, K9 district (Indiana) Business Z-Communications Company Website…
Boatanchor Legends · Tribute No. 46 Silent Key Dennis L. Brothers, WAØCBK From the Cedar Rapids Factory Floor to America’s Only Certified Collins Repair Center Born 9 February 1943, Kimball, Nebraska Silent Key 16 November 2024, age 81 Business Western…
Boatanchor Legends · Tribute No. 45 President · Collins Collectors Association Bill Carns, N7OTQ / KØCXX Art Collins’ Callsign Trustee, Editor of the Signal, Keeper of the Wimberley Shack Education BSEE 1964, MS Plasma Physics 1965, U. of Illinois First…
Boatanchor Legends · Tribute No. 44 Co-Founder · Collins Collectors Association Jay Roman, KBØATQ The Third Founder, and the Voice that Put the CCA Into Print First CCA Net Check-in 30 December 1990 CCM Founding Publisher June 1991 Original Board…
Boatanchor Legends · Tribute No. 43 Silent Key Bud Whitney, K7RMT “K7 Rocky Mountain Time” — The Bench That Kept the Collins Fleet Alive Born 24 October 1919 Silent Key circa 2010–2012 Callsign Meaning K7 Rocky Mountain Time Workshop Wimberley,…
Boatanchor Legends · Tribute No. 42 Active · Collins Engineer Rod Blocksome, KØDAS Collins Engineer, Historian, and the Man Who Brought a KWM-3 to Dayton First Licensed 1960 as KNØDAS Education BSEE 1968, MSEE 1973, Kansas State Career 42 years,…
Boatanchor Legends · Tribute No. 41 Silent Key Warren B. Bruene, W5OLY The Quiet Engineer Who Made Single Sideband Practical Born 1916, Iowa Silent Key 28 September 2013 Earlier Call WØTTK Home QTH Richardson, Texas If you have ever spoken…
Boatanchor Legends · Tribute No. 40 Silent Key Bill Wheeler, KØDEW The Quiet Founder of the Collins Collectors Association Born 18 July 1939 Silent Key 17 April 2020 First Licensed 1956 as KNØDEW Home QTH Lebanon, Missouri On a Sunday…
ARRL Year of the Club · 2026 Club QSO Party The operating event designed FOR clubs, BY clubs The ARRL has officially declared 2026 the Year of the Club, and a brand-new on-the-air event has been launched specifically to energise…
Collins KWM-2 / KWM-2A Field Service Some KWM-2 / 2A Tricks A re-issue and enrichment of the January 2016 CCAE field-service article by Georges Ricaud, F6CER (CCAE #098), with primary-source cross-references for the Collins Collector community. Front panel of the Collins KWM-2A — photograph…
GPS-disciplined crystal channels for the Hammarlund SP-600-JX Bringing parts-per-billion frequency stability to a 1950s spy-radio classic using a $18 programmable crystal module and a GPS receiver The Hammarlund SP-600-JX is one of the great communications receivers of the vacuum-tube era…
Capacitor Selection for Vintage Receiver, Transmitter, and Transceiver Restoration A practical reference for choosing replacement capacitors in premium HF tube equipment — from receivers like the R-390A and SP-600, through transmitters like the 32S-1 and Apache TX-1, to transceivers like…
Low-Noise Resistor Selection for Vintage Receiver, Transmitter, and Transceiver Restoration A practical reference for choosing replacement resistors in premium HF tube equipment — from receivers like the R-390A and SP-600, through transmitters like the 32S-1 and Apache TX-1, to transceivers…
The Boatanchor SDR Integration Series: Index and IF Buffer Amplifier Reference A consolidated index to the five SDR integration articles, plus a shared technical appendix on the buffered IF tap that most of them depend on. Over five companion articles,…
Choosing an SDR for the Collins KWM-2A Transceiver The fifth in the Boatanchor SDR series — and the receiver Collins already built with external-receiver integration in mind. Companion articles: R-390A, Hammarlund SP-600, Collins 51S-1, and Collins S-Line 75S-1 / 32S-1…
Choosing an SDR for the Collins S-Line Station: 75S-1 Receiver and 32S-1 Transmitter The fourth in the Boatanchor SDR series — and the first to cover a complete transmitting station rather than a single receiver. Companion articles: R-390A, Hammarlund SP-600,…
Choosing an SDR Front-End for the Collins 51S-1: Factory Outputs, Foresight, and Mechanical Filters The third in the Boatanchor SDR series — and the easiest of the three receivers to integrate with a modern spectrum display. Companion articles: This piece…
Choosing an SDR Front-End for the Hammarlund SP-600: Variants, Architectures, and Companions A variant-aware guide to pairing the Hammarlund Super-Pro 600 with a modern spectrum display — because the SP-600 you own may not be the SP-600 the other fellow…
Choosing an SDR Front-End for the R-390A: A Comparison Matrix A field guide for pairing the Cold War’s finest analog HF receiver with a modern spectrum display. The R-390A/URR was the most precise general-coverage HF receiver the US military ever…
RFI Analysis & Mitigation Engineering Guide VK6ADA — Boatanchor & Solid-State Technical Library Collins HF-380 Transceiver RFI Analysis & Mitigation Engineering Guide Internal emitters, external ingress paths, ferrite selection, and installation-grade RFI engineering for the military/commercial variant of the KWM-380.…
Collins Solid-State Restoration Series · Commercial / Government Variant Collins HF-380 Transceiver — Tantalum Capacitor Replacement Reference Guide A risk-prioritised service reference for the ~200-unit commercial/military variant of the KWM-380, with specific attention to the high-duty-cycle service profile that distinguishes…
Boatanchor Legends · Tribute Series Wayne Spring W6IRD · 1949–2025 Silent Key The west coast’s master of the Collins KWM-380 and HF-380, a Southern California DX Club president, and one half of ham radio’s most devoted husband-and-wife restoration team. Wayne…
Spectrum Pollution · Advocacy Brief · April 2026 Starlink and the Silent Assault on the Low-Frequency Radio Spectrum How Unintended Electromagnetic Radiation from LEO Mega-Constellations Threatens Radio Astronomy, Weak-Signal Work, and the DX-er’s Night Sky — and What Amateur Radio…
KWM-380 Tantalum Capacitor Replacement Reference Board-by-Board Location Guide, Risk Assessment & Replacement Recommendations Mike Peace VK6ADA • r-390a.net • vk6ada.com.au • April 2026 This reference accompanies the Collins KWM-380 RFI Analysis & Mitigation Guide. A site visitor asked for a…
COLLINS KWM-380 RFI Analysis & Mitigation Guide A Comprehensive Engineering Reference for Reducing Noise Floor and Improving HF Signal-to-Noise Ratios Mike Peace VK6ADA • r-390a.net • vk6ada.com.au • April 2026 • Rev 1.0 1. Introduction The Rockwell Collins KWM-380 (introduced…
Avionics History — Cold War Electronic Warfare The AN/APR-9B and AN/APA-70C on the AF-2W Guardian: Passive Radar Homing in Cold War ASW How the Grumman Guardian’s hunter variant used AIL/Collins electronic countermeasures equipment to detect, bear on, and home toward…
R-390A Restoration Series — Power Supply Solid-State Replacement for the R-390A 26Z5W Rectifier Tubes Eliminating a critical obsolescence bottleneck in the PP-621/URR power supply — with full attention to B+ voltage compensation, heater string integrity, RFI suppression, and long-term reliability.…
Collins 516F-2 Power Supply Transformer T1 Wire Identification Guide When the insulation fails and the colours disappear — mapping every winding from the inside out. A practical restoration reference for the CCA community The Problem The Collins 516F-2 power supply…
Boatanchor Legends: Bob Sternowski, WB0LBI — From the Collins Radio Bench to Venus Boatanchor Legends — A Tribute Series Robert “Bob” Sternowski WB0LBI — Silent Key Collins Radio • Softronics Ltd. • NASA • HF Engineering Pioneer Bob Sternowski spent…
Avionics Reference — ARINC 410 / 566A Series, Part 3 The Complete Collins 618M Lineage From ARINC 410 Origins (618M-1) to ARINC 566A/429 (618M-5) · The 313N Series Map · Gables Panel Pairings Confirmed CORRECTIONS & ENRICHMENT FROM JAN SP5XZG…
VK6ADA — Boatanchor Technical Library Care and Feeding of Power Grid Tubes in Vintage Collins Radio Equipment A Modern Reference Guide in the Spirit of Eimac’s Classic Application Bulletin Prepared April 2026 · Fact-Checked & Enriched Edition · Mike Peace…
Collins Collectors Association — Technical Bulletin Commentary CCA Technical Bulletin 1 Understanding and Mitigating S-Line Transmitter Spikes BULLETIN REF: CCA-TB-001 · APPLIES TO: 32S-1 · 32S-3 · 32S-3A · KWM-2/2A · COMMENTARY: VK6ADA, April 2026 ⚠ Priority Action Required —…
Collins 51J-4 Known Issues & Fault Diagnosis General-Coverage Receiver: PTO Endpoint Drift, Oil Tub Capacitor Failures, AVC Anomalies & Mechanical Filter Issues Community-documented problems and proven fixes for the Collins 51J-4 lab-grade general-coverage receiver — covering the 70E-15 PTO, F500B…
Collins S-Line Station Grounding & Bonding RF Ground, Audio Ground & Chassis Ground Are Three Different Things Incorrect bonding between the 75S-3, 32S-3, 312B-4, 30L-1, and 516F-2 is behind a significant proportion of hum, buzz, and RFI complaints — this…
Collins 32S-3 & 32S-3A Known Issues Transmitter-Specific: Carrier Balance Drift, ALC Time Constant, PA Neutralisation Loss & More Community-documented problems, factory service bulletins, and proven fixes for the most common S-Line transmitter restoration issues — the transmitter companion to the…
Web-888 SDR Integration Series National HRO-60 + Web-888 SDR Integration First Published SDR Integration Guide for the Iconic National Boatanchor The HRO-60 has no factory IF output and no existing SDR integration documentation — this guide provides the complete procedure…
Collins 75S-3 & 75S-3A Known Issues Community-Documented Problems, Factory Service Bulletins & Proven Fixes AGC anomalies, product detector noise, PTO drift, bandswitch oxidation, frozen trimmers, Black Beauty capacitors, and the service bulletins that address them — a consolidated reference for…
Web-888 SDR Integration Series Collins 51J-4 Receiver + Web-888 SDR Integration The Easiest Integration in the Series — The 51J-4 Has a Factory 50Ω IF Output No internal modification required — the Collins 51J-4’s rear-panel IF OUTPUT connector (J104) provides…
Collins S-Line AGC System Explained Delayed AGC with Separate Threshold, Dual Time-Constant Network & S-Meter Drive Understanding the 75S-3B/3C AGC loop is essential for diagnosing sensitivity and overload complaints — the AGC threshold, attack/decay time constants, noise clipper, and S-Meter…
Collins 32S-3 PA Neutralisation — Step by Step The Procedure Most Likely to Be Skipped — And Most Consequential When Wrong Definitive guide to 6146 PA neutralisation in the 32S-3/3A, KWM-2/2A, and 32S-1 — covering both the ceramic trimmer and…
Collins KWM-2/2A Carrier Balance Optimisation Suppressed Carrier Level Directly Affects Transmit Audio Quality The two-stage carrier suppression architecture, the balanced modulator null procedure, the first balanced mixer trim, and why the manual procedure is poorly explained — with a clear…
Collins S-Line ALC System — Theory, Faults & Wiring How the ALC Loop Works Across the S-Line Station: 75S-3C + 32S-3A + 30L-1 Common ALC interaction faults, the KWM-2A ALC connector wiring, and the complete signal flow from microphone to…
Collins Mechanical Filter Testing How to Verify Bandwidth, Shape Factor & Insertion Loss — With and Without a Spectrum Analyser Two complete test methods: Method A using a spectrum analyser with tracking generator, and Method B using only a signal…
Collins S-Line PTO Overhaul & Re-lubrication 70K-2 PTO — Cleaning, Capacitor Replacement, Shaft Seal & the Alcohol-then-Oil Lubrication Sequence The single most common restoration task across the entire Collins S-Line family — applicable to the 75S-1, 75S-3 series, 32S-1, 32S-3…
vk6ada.com.au • Collins Community Resources • April 2026 Collins Collectors AssociationTechnical Bulletins, Archives, and Community Resources — A Practical Guide The Collins Collectors Association (CCA) is the primary preservation organisation for Collins Radio technical documentation. It holds an active licence…