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…
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…
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.…
vk6ada.com.au • SDR Integration Series • Collins R-390A/URR & RX-888 Mk II RX-888 Mk II with the Collins R-390A/URRPractical Cascade Integration via the CASCADE-390 IF Tap Kit The antenna-sharing approach gives you a panadapter that happens to be near your operating frequency.…
vk6ada.com.au • SDR Remote Access Series • Vintage Receiver Integration Web-888 Remote Access SetupStep-by-Step Guide for R-390A Owners Joining the Remote Operation Community Your R-390A is in the shack. You are not. This guide walks through the complete setup for…
vk6ada.com.au • SDR Integration Series • Collins R-390A/URR & Hermes Lite 2 Hermes Lite 2 as R-390A CompanionPanadapter Integration Without Modifying the Receiver, and HL2 Transmit for CW, SSB and AM A complete integration guide for pairing the Hermes Lite…
vk6ada.com.au • Collins R-390A/URR Technical Reference Series Collins R-390A/URRBleeder Resistor Network — Function, Failure, and Correct Replacement A definitive engineering reference covering the R-390A bleeder resistor network: its three distinct functions (safety discharge, power supply regulation, and intermediate voltage division),…
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 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 marking restoration, hardware treatment, manufacturer…
I was an early advocate of the tungsten disulphide (TDS) and ethyl alcoholtechnique; The post from (+15 years ago) might of been on a thread that Ihad an active part or even initiated. I can say that the original one…