Lo‑Kata Navtex 1

Lo-Kata (Brand) Lokata Ltd.; Cornwall & Essex

Data
Forum
Pictures
Collections

  • Year
  • 1991 ?
  • Category
  • Commercial Receiver (may include amateur bands)
  • Radiomuseum.org ID
  • 369277

 Technical Specifications

  • Number of Transistors
  • Semiconductors present.
  • Semiconductors
  • Main principle
  • TRF without regeneration
  • Wave bands
  • Wave Bands given in the notes.
  • Power type and voltage
  • Storage Battery for all (e.g. for car radios and amateur radios) / 12 /24 Volt
  • Loudspeaker
  • - For headphones or amp.
  • Material
  • Plastics (no bakelite or catalin)
  • from Radiomuseum.org
  • Model: Lo‑Kata Navtex 1 - Lo-Kata Brand Lokata Ltd.;
  • Shape
  • Tablemodel, with any shape - general.
  • Dimensions (WHD)
  • 300 x 130 x 90 mm / 11.8 x 5.1 x 3.5 inch
  • Notes

  • Lo‑Kata Navtex 1

    Category
    Marine receiver (NAVTEX / 518 kHz narrow‑band direct‑printing telegraphy)

    Purpose
    Dedicated NAVTEX receiver for small and medium‑sized craft, designed to automatically print navigational and meteorological warnings transmitted on 518 kHz under the IMO GMDSS system.

    Technical Data

    Specification Details
    Receive frequency 518 kHz
    Modulation type FSK ± 85 Hz
    Sensitivity 50 Ω input < 1 µV e.m.f. for < 4 % error rate
    Selectivity 20 dBµV for < 4 % error rate ± 300 Hz at ± 1 kHz off‑channel
    Spurious response rejection > 80 dB (100 kHz – 30 MHz, except 514–522 kHz band)
    Audio output 3.5 mm headphone socket ≈ 100 mV from 1 kΩ
    Antenna inputs 50 Ω / Hi‑Z / active antenna (50 Ω internally powered)
    Printer 40‑column thermal type (112 mm paper width)
    Power requirements 12 or 24 V DC (10.8 – 31.5 V DC)
    Power consumption < 100 mA idle, < 1 A printing
    Controls Off/On, Store, Print Status, Feed Paper; Setup/Test Accept/Reject
    Indicators Signal LED, Alarm LED

    Circuit Description
    The receiver is a t.r.f. design with a narrow‑band crystal filter and mixer converting the RF signal to audio FSK (1615 Hz / 1785 Hz). A microprocessor decodes the bit stream, stores messages, and drives the thermal printer. The block diagram (Short Wave Magazine, Feb 1992 p. 10) shows terminal, receiver, processor, display, and printer boards with opto‑switch feedback.

    Historical Context

    Lo‑Kata Ltd. of Falmouth produced a range of marine electronics including direction finders, EPIRBs, and NAVTEX receivers. The Navtex 1 was marketed around 1991–1992 and complied with CCIR 476‑2 and 540 data formats. It was featured in Short Wave Magazine (Jeff Harris G3LWM, Jan–Feb 1992) as part of a two‑part technical overview of the NAVTEX network and receiver design.

  • Net weight (2.2 lb = 1 kg)
  • 2 kg / 4 lb 6.5 oz (4.405 lb)
  • Mentioned in
  • -- Original prospect or advert (Short Wave Magazine (Jeff Harris G3LWM, Jan–Feb 1992))
  Short Wave Magazine (Jeff Harris G3LWM, Jan–Feb 1992) 2880 KB
  • Documents regarding this model
  • Author
  • Model page created by Gary Cowans. See "Data change" for further contributors.

 Collections | Museums | Literature

 Forum