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USING A NEXTION DISPLAY TO UPDATE A CLASSIC KEYER RICK DUBBS, WW9JD  KIT
BUILDING IS ONE OF MY FAVORITE HAM RADIO ACTIVITIES.  IN 1984, I PURCHASED
THE HEATHKIT SA5010 UMATIC MEMORY KEYER.  ITS PICTURED IN THE SPLASH SCREEN
OF MY UPDATED KEYER IN THE LEAD PHOTO.  THE UMATIC HAD A HUGE 240 CHARACTER
COMMAND MEMORY AND A 22 KEY MEMBRANE KEYPAD.  IT COULD USE UP TO 10
VARIABLE LENGTH MEMORIES AND GENERATED REPEATABLE RANDOM CW FOR CODE
PRACTICE.  ITS MAIN FLAW WAS ITS CAPACITIVE TOUCH PADDLES, WHICH SEEMINGLY
WORKED WELL FOR ONLY A FEW HAMS.  IVE BEEN WANTING TO BUILD AN UPDATED
KEYER WITH MORE MEMORY, A PHYSICAL IAMBIC PADDLE, AND A TOUCH SENSITIVE LCD
SCREEN.  I RECENTLY FOUND THE NEXTION NX4832K035 ENHANCED 3R5 INCH HMI
TOUCH DISPLAY LCD MODULE AVAILABLE FROM NEXTION.  TECH.  IT CONNECTS TO AN
ARDUINO OR RASPBERRY PI WITH JUST A PAIR OF SERIAL WIRES, AND PROVIDES A
USER INTERFACE UI DESIGN ENVIRONMENT THAT IS INDEPENDENT FROM THE MAIN
PROGRAM CODE KNOWN AS THE ARDUINO SKETCH.  THIS WAS THE BASIS FOR MY KEYER.
FIGURE 1 SHOWS MY UPDATED UMATIC2 KEYER, WITH PADDLES ATTACHED, NEXT TO THE
UMATIC KEYER WITH ITS CAPACITIVE PADDLES.  THE ORIGINAL UMATIC KEYER HAD 10
MEMORIES.  MY UPDATED VERSION HAS 110 MEMORIES.  THE NEXTION DISPLAY CAN
HAVE AS MANY AS 256 CONTROLS ON EACH SCREEN, AND AS MANY AS 256 SCREENS.
THE PROJECT DOESNT NEED TO HAVE A LARGE ENCLOSURE TO ACCOMODATE BUTTONS,
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