[sdiy] Glowing diode on Casio CT-510 analog board?

Roman Sowa modular at go2.pl
Tue May 23 14:38:40 CEST 2023

Yes, the JP8, one of very few synths showing active voices.
It helps a lot during service or calibration.
Some synths provide at least pin header with gates of individual voices, 
but most of the time it's just "naah, take a guess, we don't care about 
service people, stab a scope probe somewhere and burn $50 vintage chip 
by accidental short ha ha ha!"

You can see those JP8 LEDs clearly in my flying drone video about JP8 
playing all voices unisono:


W dniu 2023-05-23 o 12:07, Adam (synthDIY) pisze:
>> On 23 May 2023, at 5:52 pm, Roman Sowa <modular at go2.pl> wrote:
>> If it glows, it is LED.
>> Those kind of early LEDs were used at least in one of the Korgs, Maybe Poly6 or Poly61, can't recall now, to indicate active voice.
>> I was shocked too when I saw them first.
> Actually, my Jupiter 8 has internal LEDs which are activated by throwing the "test mode" switch. As you say, they indicate which voice board is sounding with each key press.
> A

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