Decca Radar TMS1230C True Motion S-Band Marine Radar System 65165 65170 65164

Decca Radar TMS1230C True Motion S-Band Marine Radar System 65165 65170 65164

The Decca Radar TMS1230C is a vintage True Motion S-Band (10cm) marine radar system manufactured by Decca Radar Ltd. in England. It consists of three primary units: the Type 65165 Display Console (Class B), the Type 65170 Transceiver (Class B), and the Type 65164 True Motion Unit (Class B). True Motion radar systems display both own-ship and target motion relative to a fixed geographic reference, allowing the navigator to see a stabilized picture of the surrounding sea — a significant capability for vessels operating in complex or congested waters. Research indicates this radar model was fitted aboard the Polar Duke, a vessel operated for Antarctic and Southern Ocean scientific research.

Specifications & What's Included

• Model: Decca Radar TMS1230C
• Radar band: S-Band, 10cm wavelength
• Display Console: Type 65165, Class B — Serial No. P0860 (Rev BD)
• Transceiver: Type 65170, Class B — Serial No. P2219
• True Motion Unit: Type 65164, Class B — Serial No. P2058 (Rev AD)
• Display compass safe distance: Standard 6.5 ft / Steering 4 ft
• Transceiver compass safe distance: Standard 12 ft / Steering 7.5 ft
• Country of manufacture: England (United Kingdom) — Decca Radar Ltd.
• Front panel controls include: log/sea/manual selectors, shift, brilliance, tune, range, bearing indicator, relative/true motion mode selector, course-made-good indicator
• Internal circuit boards and wiring present in both display console and transceiver (visible in interior photos)
• Transceiver contains magnetron assembly with high-voltage discharge warning label
• No manual or peripherals included
• Display console and transceiver only — antenna/scanner not included

Applications

S-Band True Motion marine radar systems of this type were used aboard oceangoing research vessels, icebreakers, patrol ships, and commercial vessels from the 1960s through the 1980s. S-Band (approximately 3 GHz, 10cm wavelength) radar was preferred for long-range maritime navigation because it performs well in heavy precipitation and sea clutter — conditions common in polar and open-ocean environments. True Motion display capability was a premium feature that stabilized the radar picture against the ship's own movement, making it easier to track other vessels, coastlines, and navigational hazards accurately over time. Decca Radar Ltd. was a leading British manufacturer of maritime navigation electronics for decades, and systems like the TMS1230C were installed on vessels operated by governments, research institutions, and commercial shipping lines. Today, units like this are sought by maritime museums, collectors of vintage navigation equipment, and restoration enthusiasts. The known provenance linking this system to the Polar Duke Antarctic research vessel adds significant historical interest.