W8USR - Station Equipment
Astron RS-35A Heavy-Duty Linear DC Power Supply
Technical Specifications
The Astron RS-35A is a rugged, heavy-duty linear regulated DC power supply widely recognized for its high reliability and RF-silent operation. Built with a substantial linear transformer, it provides exceptionally clean power free of the switching noise common in modern supplies. The specific design parameters for this unmetered "A" model include:
| Engineering Property | Manufacturer Technical Specification Value |
|---|---|
| Primary Output Voltage | 13.8V DC ± 0.05 Volts (Internally adjustable from 11.0V to 15.0V) |
| Current Capacity (Continuous) | 25 Amps (Continuous Duty cycle profile) |
| Current Capacity (Surge/ICS) | 35 Amps (Intermittent Commercial and Amateur Service peak load) |
| Input Line Voltage | 105–125V AC, 60 Hz Standard AC Power Line Input |
| Ripple Voltage Profiles | Less than 5 mV Peak-to-Peak (At full capacity rated load and low line levels) |
| Integrated System Safeguards | Fold-back current limiting for short-circuit protection and automatic crowbar overvoltage protection |
| Telemetry Monitoring | Unmetered sleek front panel layout configuration |
| Cooling Infrastructure | Heavy-duty chassis-mounted external heat sink optimized for fanless/silent operation |
| DC Output Hardware Links | Heavy-duty 1/4"-20 threaded screw-type terminals sitting on the rear enclosure wall |
| Physical Footprint Dimensions | 5" High x 11" Wide x 11" Deep |
| Net Equipment Weight | 27.0 Pounds (Linear transformer ballast mass) |
Radio History & Station Integration
The Astron RS-35A holds a prominent place in the history of station W8USR, serving as the very first primary power supply deployed at our active radio desk terminal. Originally sourced and purchased at the world-famous Dayton Hamvention, this rugged unit initially anchored the console to supply heavy-duty DC rails for our Kenwood TS-140S transceiver, the At-250 Automatic Antenna Tuner and other various pieces of equipment. As the station continued to evolve, in August 2001, we upgraded our primary rig from the Kenwood to a new premium high end Yaesu FT-1000MP Mark V transceiver that used its own external AC power supply (the Yaesu FP-29). At that point, the RS-35A continued to act as our primary bench 12 volt workhorse until the station moved forward with a strategic infrastructure consolidation program. To achieve our goal of driving all 12V DC station equipment from one central source, the RS-35A was phased up to our current high-capacity Astron RS-70M power system, which simultaneously replaced the standalone Pyramid PS-15K5 unit that had been dedicated to powering the station's Galaxy DX-959G Citizen Band radio transceiver.
Station Role
Throughout its extended active operational lifecycle at the W8USR operating deck, the Astron RS-35A power supply functioned as the primary foundation of the 12-volt DC power plant infrastructure for the entire radio station, with the sole exception of the separate Citizen Band station hardware setup. By delivering a rock-solid, low-ripple electrical baseline across our primary HF voice equipment arrays, it ensured clean signal modulation and dependable power stability over decades of on-air operations.