Note
The RPW-3 was a commercial communications receiver featuring the logo of the Press Wireless company. It was built with typical high-quality National craftsmanship and featured an imposing rack-mountable design. Mechanically and cosmetically, it shared the exact same chassis layout, under-chassis appearance, and knob design as the National NC-183.
Circuit Design and Core Architecture
– Both receivers utilize the exact same fundamental design, operating as single-conversion receivers with a 455 kc IF and a standard National crystal filter.
– Both models feature a total of 5 band positions.
Frequency Coverage and Bands
– The NC-183 covers 540 kc to 31 mc across four bands, with its fifth band dedicated to the 6-meter amateur band.
– The RPW-3 covers a slightly modified 540 kc to 30 mc across four bands, while its fifth band replaces the 6-meter coverage with a longwave band covering 200 to 400 kc.
Dial Styling and Cosmetics
– The NC-183 is equipped with a bandspread dial featuring detailed markings specifically for the amateur radio bands, wrapped in standard National amateur styling.
– The RPW-3 strips away the amateur markings, instead utilizing a simple 0–200 division logging scale on the bandspread dial. It also features customized front-panel engraving and custom dial scales tailored for Press Wireless.
Because so few variations exist beyond changing one set of coils, altering the dial scales, and changing the front-panel engraving, the RPW-3 may have simply been a factory shop/marketing model rather than a mass-produced unit. The "RPW-3" designation itself most likely stands for "Receiver, Press Wireless, Version 3".
