vk6ada.com.au • Yaesu FT-200 Technical Series Yaesu FT-200 / FT-250 / Tempo OneFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FT-200 failure modes covering the rare 7360 balanced modulator tube, the solid-state…
vk6ada.com.au • Yaesu FT-902 Technical Series Yaesu FT-902DM / FT-902D SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FT-902 failure modes — including six failures unique to or significantly different in the…
vk6ada.com.au • Yaesu FT-901 Technical Series Yaesu FT-901 SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FT-901 failure modes spanning the PLL synthesiser, receive section, transmit/PA section, and power supply. Covers all…
vk6ada.com.au • Yaesu FT-101EE Technical Series Yaesu FT-101EE TransceiverFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FT-101EE failure modes across transmit and receive sections. The FT-101EE was the most widely sold variant…
vk6ada.com.au • Yaesu FT-101E Technical Series Yaesu FT-101E SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FT-101E failure modes across both the transmit and receive sections, with a structured two-tier component replacement…
vk6ada.com.au • Yaesu FL-101 Technical Series Yaesu FL-101 TransmitterFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FL-101 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers all…
vk6ada.com.au • Yaesu FR-101 Technical Series Yaesu FR-101 SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable FR-101 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers both…
vk6ada.com.au • Lafayette HA-350 Technical Series Lafayette HA-350Failure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable HA-350 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers all production…
vk6ada.com.au • Hammarlund HQ-110 Technical Series Hammarlund HQ-110 SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable HQ-110 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers all…
vk6ada.com.au • Hammarlund HQ-180 Technical Series Hammarlund HQ-180 SeriesFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable HQ-180 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers all…
vk6ada.com.au • Collins 51S-1 Technical Series Collins 51S-1Failure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable Collins 51S-1 failure modes, with a structured two-tier component replacement kit and four preventive modifications. Covers all…
vk6ada.com.au • Collins KWM-2 / KWM-2A Technical Series KWM-2 / KWM-2AFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable KWM-2/2A failure modes, with a structured two-tier component replacement kit, four preventive circuit modifications,…
vk6ada.com.au • Collins R-390/URR Technical Series R-390/URRFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable R-390/URR failure modes, with a structured two-tier component replacement kit and four preventive circuit modifications. The R-390/URR is…
vk6ada.com.au • Collins R-388/URR Technical Series R-388/URRFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable R-388/URR failure modes, with a structured two-tier component replacement kit and four preventive circuit modifications to eliminate them…
The Visual–Aural Radio Range (VAR)History, Technology & Australia’s 30-Year Adoption LFRR → Lorenz → VAR → VOR • 112–118 MHz • Blue & yellow indicator • 1937–1980 • Australian DCA network • ARC Type 16 • Collins airborne equipment • Weston…
Boatanchor Radio Legends Scott V. Johnson W7SVJ / AFA6SJ · Scottsdale, Arizona Engineer, aviator, and the foremost documenter of Collins Radio’s military and avionics product legacy — the man who carries Collins into the cockpit and onto the flightline, and…
Collins Collectors Association Worldwide Regional Groups, Contact Details & Net Schedules Compiled March 2026 · Sources: collinsradio.org · ccae.tm6cca.com · ccaeitaly.com · Mike Peace VK6ADA / r-390a.net Administrator 🇺🇸🇨🇦 Collins Collectors Association (CCA) — North America & Worldwide Parent The…
CCA Friday Night West Coast75 Metre Net Collins Collectors Association • 3895 kHz LSB • Every Friday • 1900 Pacific / 0200Z Saturday • Net Manager: Dennis Kidder W6DQ • Inyokern CA ‣ VK6ADA.COM.AU — CCA Net Guide • March 2026…
vk6ada.com.au • Collins R-390A/URR Technical Series R-390A/URRFailure Prevention Kit — Component & Modification Design A complete engineering analysis of the ten predictable R-390A failure modes, with a structured two-tier component replacement kit and four preventive circuit modifications to eliminate them…
vk6ada.com.au • Collins S-Line Technical Resources Collins Radio Equipment ManualsCCA Technical Archive Directory A complete mirror index of all Collins Radio equipment manual PDFs hosted by the Collins Collectors Association. Links open directly on the CCA server. No login required.…
vk6ada.com.au • Collins S-Line Safety Series Collins 516F-2 & S-LineThe Switched Neutral AC Power Design Defect A comprehensive guide for operators worldwide: why the 516F-2 presents a live mains hazard when switched off, how mains voltage, plug polarity and wiring…
vk6ada.com.au • Collins KWM-2 Technical Series Collins KWM-2 / KWM-2AVietnam Modification (SCED 11b) Complete process plan — PTO voltage stabilisation using a 150 V zener diode. Includes parts list with suppliers, step-by-step installation procedure, Quality Assurance plan, and pre-power test protocol.…
vk6ada.com.au • Collins Radio Heritage Series • Second Edition Prolific Authors ofCollins HF Radio Equipment Eight writers who documented the most revered name in amateur radio — from circuit notes to biography, from service bulletins to space history. All known…
Collins KWM-2 PTO Frequency Jump Troubleshooting Guide By VK6ADA • March 25, 2026 This guide documents the troubleshooting process for an intermittent 9 kHz frequency jump in a Collins KWM-2/2A transceiver that occurs after 1-2 hours of operation. Based on…
Wulfsberg Electronics & Collins Radio:Research Note — Second Edition Paul Wulfsberg • P.G. Wulfsberg at Collins Radio, Cedar Rapids (IEEE, 1963) • Paul Wulfsberg at King Radio (NASA, 1970) • Arthur F. Wulfsberg at Collins Radio (Apollo) • K.N. Wulfsberg…
Collins Radio Avionics —Historical Introduction Dates & Archive Resources Collins • 618M • 860E-1 (1961) • 51R-7A • VIR-30 • DME-40 • 51RV • ARINC 410 • Pro Line I / II / 4 / 21 / Fusion • EFIS-85/86…
Collins KWM-2 / KWM-2ARestoration Deep-Dive Arthur Collins’ Masterpiece • 1959–1977 • The Compact S-Line That Went to War Of all the rigs to emerge from Cedar Rapids, Iowa during the golden age of amateur radio engineering, the Collins KWM-2 occupies…
Alpha 87A Linear Amplifier:Restoration & Service Guide 3CX800A7 Tubes • PIN Diode T/R Switching • Microprocessor Control • Fault Code Reference • Cabinet & Safety 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 1,500 W Continuous — 3CX800A7 💻 Microprocessor Controlled…
Alpha / ETO 91B Linear Amplifier:Restoration & Service Guide 4CX800A/GU74b Tetrodes • Grounded-Cathode Grid-Driven • Vacuum Relay QSK • Electronic Bias System • Cabinet & Safety 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 1,500 W — 4CX800A/GU74b Tetrode 🇧🇬 Assembled…
Alpha 9500 Linear Amplifier:Restoration & Service Guide 3CX1500A7/8877 Triode • Five I²C Microprocessors • Auto Mains Tap • Gigavac Vacuum Relays • Three Stepper Motors • Cabinet & Safety 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 1,500 W — 3CX1500A7/8877…
Alpha 8410 Linear Amplifier:Restoration & Service Guide 4CX1500B Bayonet Tetrodes • Manual Tune • Swamped-Grid Input • EBS • PIC Microcontroller • Dual Input Match Relay • Cabinet & Safety 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 1,500 W —…
Emtron DX-1A Linear Amplifier:Restoration & Service Guide GU74B (4CX800A) Tetrode • AMPC Control Board • TRIAC Soft-Start • EBS Jumper • Optional Jennings QSK • Emona Electronics Sydney • Cabinet & Safety 📝 VK6ADA Technical Papers 📅 March 2026 ⚡…
Emtron DX-1D Linear Amplifier:Restoration & Service Guide GU74B (4CX800A) Tetrode • RF Sub-Chassis & 9-Way Connector • Dedicated Display Board • SWR Protection • AMPC Control Board • TRIAC Soft-Start • TDA1085C • Dual Tank Coils • Emona Electronics Sydney…
Emtron DX-1SP Linear Amplifier:Restoration & Service Guide FU-728F (4CX1500B-class) Tetrode • 1,200 W CW / 1,500 W PEP • 8× 470 μF/500 V HV Bank • 40 A TRIAC Soft-Start • Dual-Polarity Screen Protection • Eimac 4CX1500B Compatible • OCC • FCC Approved 📝 VK6ADA…
Emtron DX-1V Linear Amplifier:Restoration & Service Guide 6-Metre (50 MHz) Specialist Variant • GU74B (4CX800A) Tetrode • Single-Band 50 MHz Pi-Network • AMPC Control Board • TRIAC Soft-Start • QSK Standard • Emona Electronics Sydney 📝 VK6ADA Technical Papers 📅 March 2026…
Emtron DX-2 Linear Amplifier:Restoration & Service Guide GU84B (4CX2500A) Tetrode • 27 V Heater • 1,500 W Carrier / 7 Bands • Ferrite Toroid “L” Coil • Two-Speed Blower • Ig2+/Ig2− Screen Current Metering • RF Sub-Chassis • 9-Way Connector • Emona…
Emtron DX-2A Linear Amplifier:Restoration & Service Guide GU84B (4CX2500A) Tetrode • 9-Band Full Coverage (160m–10m incl. WARC) • RF Module Schematic in DX-1D Documentation • Two-Speed Blower • Dual Temperature Sensors • All-Band Tank Circuit Upgrade • Emona Electronics Sydney…
Emtron DX-2SP Linear Amplifier:Restoration & Service Guide GU84B • 2,000 W Carrier / 2,500 W PEP • 4 kVA Transformer • Heavy-Duty H.V. Band Switch • Horizontal AMPC Board • Dual-Polarity Screen Supply • BTA40-600B TRIAC Soft-Start • 9 Bands 160m–10m incl. WARC • …
Emtron DX-2V Linear Amplifier:Restoration & Service Guide GU84B (4CX2500A) Tetrode • 6‑Metre Specialist (50 MHz) • 2,000 W Output • Single‑Band 50 MHz Pi‑Network • Dedicated 50 MHz Plate Choke • Parasitic Suppression Critical • QSK Standard • Debut: Dayton Hamvention 2010 • Emona…
Emtron DX-3 Linear Amplifier:Restoration & Service Guide GU78B (4CX3000A) Tetrode • 3,000 W Carrier / 4,000 W PEP • 9 Bands 160m–10m incl. WARC • Dual-Fan Cooling • 700 µH Plate Choke • Horizontal AMPC Board • QSKv3 (Two Relay Options) • 60–90 W…
Emtron DX-3SP Linear Amplifier:Restoration & Service Guide Two FU-728F Tetrodes in Parallel • 4,000 W Carrier / 5,000 W PEP • 3,400 V DC Plate Supply • 9 Bands 160m–10m incl. WARC • Three Bias Pots (POT3 + POT10/BS1 + POT9/BS2) • Safety…
Emtron DX-4 Linear Amplifier:Restoration & Service Guide Two GU84B (4CX2500A) Tetrodes in Parallel • 4,000 W Carrier / 5,000 W PEP • 3,100 V DC Plate Supply • Separate Standalone HV Power Supply (3 Variants) • Three-Interlock Serial Safety Chain • Auxiliary Transformer in…
Henry Radio HF Linear Amplifiers:Omnibus Restoration & Service Guide All HF Tube & Solid-State Models • 2K/3K/4K/5K/8K Series • 1963–2005 • Los Angeles, California • Grounded-Grid Triodes • 3-400Z • 3-500Z • 8873/8874/8877 • 3CX1200A7/D7 • 3CX3000A7 • 5CX1500A •…
Heathkit SB-200 Linear Amplifier:Complete Restoration Guide Circuits • Cabinet • Safety • Component Replacement • Modern Upgrades • SB-201 Coverage 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 572B Triode — 600 W Class ⚠ High Voltage Equipment Abstract. The Heathkit…
Heathkit SB-220 Linear Amplifier:Complete Restoration Guide Circuits • Cabinet • Safety • Component Replacement • Modern Upgrades 📝 VK6ADA Technical Papers 📅 March 2026 ⚡ 2 kW Class — 3-500Z Triode ⚠ High Voltage Equipment Abstract. The Heathkit SB-220 is…
Community Join the Vintage AmateurRadio Restoration Group A dedicated mailing list for amateurs who restore, study, and operate vintage HF equipment — Collins, National, Hammarlund, Hallicrafters, Drake, Heathkit, and beyond. Technical advice, restoration notes, and a community that values doing…
Collins 180S-1 Jumper Plug Engineering Design | VK6ADA VK6ADA vk6ada.com.au • r-390a.net Collins S-Line — Engineering Design Document Collins 180S-1Jumper Plug Reproduction A comprehensive engineering design for fabricating reproduction jumper plugs for the Collins 180S-1 antenna tuner — including circuit…
Collins 180S-1 Antenna Tuner Restoration Guide | VK6ADA VK6ADA vk6ada.com.au • r-390a.net Collins S-Line Accessories Restoration Series Collins 180S-1Antenna Tuner Restoration Guide A complete field guide to the cosmetic and mechanical restoration of the Collins 180S-1 pi-network antenna tuner —…
R-390/URR Restoration Guide | VK6ADA VK6ADA vk6ada.com.au • r-390a.net Collins Military Receiver Restoration Series R-390/URR ReceiverRestoration Guide A complete field guide to the cosmetic and mechanical restoration of the Collins R-390/URR military HF communications receiver — covering disassembly, the critical…
R-390A/URR Restoration Guide | VK6ADA VK6ADA vk6ada.com.au • r-390a.net Collins Military Receiver Restoration Series R-390A/URR ReceiverRestoration Guide A complete field guide to the cosmetic restoration of the R-390A/URR military HF communications receiver — covering disassembly, haze gray finish specification, panel…