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Joymega adapter on small PCB/connector (any interest?)

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Van Danjovic

Champion (321)

afbeelding van Danjovic

21-12-2019, 12:31

Wild_Penguin wrote:

Hi,

Reading this thread, did anyone actually figure out why does the transistor cause erroneous / glitched readings?

Of course I could order the known-and-confirmed adapters (or put in some NC7ST04...).

My guess is commutation speed. The transistor might switch fast with:

  • A capacitor (100..400pf) in parallel with the base resistor _/--
  • A 10k resistor from base to emitter to drain the current faster --\_
  • Reduce the resistor in collector to get in the (470..1k)Ohm range --\_

Of course that would elevate the component count, and that's why I think joymega adapter builders prefer to use the integrated circuit.

Van sd_snatcher

Prophet (3608)

afbeelding van sd_snatcher

22-12-2019, 03:15

Quote:

or put in some NC7ST04...

The NC7ST04 is an excellent choice. The JoyMega2 is made with this chip and is very compact. I tested it and it works like a charm.

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