W8USR - Station Equipment
Pyramid PS-15K5 Power Supply & CB Station Core
Technical Specifications
The Pyramid PS-15K5 is a linear regulated bench DC power supply engineered to offer dependable AC-to-DC power performance. Operating on a standard 105–125V AC input, it delivers a highly stable 13.8V DC output with automatic electronic overload and short-circuit protection. At station W8USR, this hardware serves as the exclusive dedicated electrical plant powering our Galaxy DX-959G station array. The combined structural and operational specifications include:
| Hardware / Operational Property | Technical Specification Value & System Parameter |
|---|---|
| Power Supply Output Voltage | 13.8V DC ± 0.3V (Internally adjustable from 11.0 to 15.0 VDC) |
| Power Supply Amperage | 10 Amps Continuous Constant / 12 Amps Surge Peak (ICS) |
| Power Supply Ripple Profile | Less than 5 mV RMS ripple voltage peak-to-peak under full rated load |
| Power Supply Built-In Protections | Fold-back current limiting short-circuit safeguard and automatic crowbar overvoltage protection |
| Radio Model Deployed | Galaxy DX-959G Mobile Citizen Band (CB) Transceiver Base Platform |
| CB Channel Allocations | Full 40-Channel coverage spectrum utilizing Phase-Locked Loop (PLL) synthesis |
| Frequency Spectrum Range | 26.965 MHz to 27.405 MHz High Frequency (HF) Band allocation |
| Transmitter RF Power Output | AM: 4 Watts Carrier Output • SSB: 12 Watts Peak Envelope Power (PEP) |
| Transmitter Spurious Emissions | -55 dB Suppression relative to fundamental carrier limits |
| Audio Frequency Response | Optimized for communications intelligibility from 300 Hz up to 2500 Hz |
| Receiver Target Sensitivity | AM: 0.5 µV for 10 dB S+N/N • SSB: 0.25 µV for 10 dB S+N/N |
| Integrated Radio Visual Features | 5-digit amber/green LED frequency counter, blue channel/meter display, Starlite faceplate |
| Radio Physical Footprint | 7.875" Wide x 9.25" Deep x 2.125" High |
Radio History & Station Integration
The acquisition of the Pyramid PS-15K5 power supply marks a specific milestone in the physical layout expansion of station W8USR. The unit was purchased explicitly when the decision was finalized to branch out and integrate a dedicated Citizen Band radio monitor terminal directly into our permanent desktop operating console. To keep our high-frequency amateur operations completely isolated from local radio traffic and monitoring checks, the PS-15K5 was brought in to power the newly added Galaxy DX-959G mobile transceiver. During this operational era, the unmetered Astron RS-35A sat right alongside the Pyramid deck, carrying the extensive electrical load for the rest of our amateur shortwave equipment. This dual-supply layout remained standard until our later consolidation program introduced the high-capacity Astron RS-70M power rail system, allowing us to safely transition all bench devices over to a singular central transformer vault.
Station Role
The primary station role of the Pyramid PS-15K5 linear power supply was to function as the exclusive, low-ripple source of 12-volt DC power for our Galaxy DX-959G Citizen Band transceiver layout. By establishing a dedicated electrical line completely independent of our amateur arrays, it guaranteed that high-duty cycle AM and Single-Sideband (SSB) transmissions on the 11-meter spectrum never interfered with or pulled voltage from the primary bench equipment. The Galaxy DX-959G radio itself served as our central listening post for regional road logistics, local signal propagation tests, and neighborhood monitoring nets. Key specialized controls on the radio faceplate—such as variable talkback modulation circuits, variable power outputs, an automatic standing wave ratio (SWR) alert circuit with high-SWR warning lights, and a ±1.0 kHz receiver clarifier—were maintained with peak stability thanks to the clean DC power line supplied by the Pyramid transformer.