New Curtis Keyer ICHi,

Discussion in 'Homebrew and Kit Projects' started by WA9SVD, Jul 25, 2021.

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  1. WA9SVD

    WA9SVD Ham Member QRZ Page

    Hi,

    MFJ "bought" Curtis, who made the "8044" keyer IC. That is now discontinued, being replaced by the 8045 IC. Unfortunately, the two are NOT "pin compatible," Has anyone come up with a DIY project using the new 8045 IC?
     
  2. W9GB

    W9GB Ham Member QRZ Page

    John Curtis, K6KU (SK, 2018) stopped selling his Keyer chips in late 1990s and
    MFJ purchased the Curtis 8044 IC line at the Millennium (2000).

    John Curtis ceased his company’s operations on April 1, 2000 (retirement).
    John became a Silent Key on June 4, 2018
    http://www.arrl.org/news/curtis-keyer-chip-developer-jack-curtis-k6ku-sk
    ===
    Curtis 8045 Series Keyer-on-a-Chip
    Application Note
    Repeater Builders TIP Repository
    http://manuals.repeater-builder.com/Vectronics/CK-8045ABM/CK-8045ABM.pdf

    Curtis 8044 Series Keyer-on-a-Chip
    Application Note (1992)
    https://www.k7qo.com/8044print.pdf
    ==
    As Noted, the MFJ 8045ABM (28-pin in PDIP or SSOP, $39.95) is not pin compatible
    with the earlier Curtis 8044 designs.
    https://mfjenterprises.com/products/ck-8045abm

    Legacy Curtis chips (8044-series) were used by a variety of Kits and Assembled Keyers,
    When a failed 8044 requires replacement, it is up to Knowledge and Skills of the Radio Amateur to either create a New PC board for the available 8045ABM or DIY Build an Adapter board.

    FAR Circuits has a Bare PC Boards for a variety of Keyer Designs.
    https://www.farcircuits.net/
    The 1994 ARRL Handbook design by Curtis (obsolete 8044ABM),
    has not been updated for the 8045ABM.
    https://www.farcircuits.net/Keyers.html

    gb
     
    Last edited: Aug 6, 2021

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