Collins S-Line Restoration Series Waking a Sleeping Collins Restoring a 75S-3B Receiver After 50 Years in Storage Mike Peace VK6ADA · r-390a.net Administrator · vk6ada.com.au A Collins 75S-3B that has slept in a shed, attic, or estate garage since the…
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…
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,…
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…
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 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 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 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 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 S-Line Technical Reference • IF Filter Guide Collins S-Line and KWM-2/KWM-2ACrystal and Mechanical Filter Comprehensive Reference — All Part Numbers, Specifications, BFO Crystals, and Equipment Cross-Reference A definitive reference for the 75S-1, 75S-2, 75S-3, 75S-3A, 75S-3B, 75S-3C,…