Oakley OMS-820 User Manual
Page 9
Each LED is turned on and off by PNP transistors. When the transistor is off, the LED has
current going through it and is on. When the transistor is on, it ‘shorts out’ the LED and the
voltage across it drops and the LED is turned off. There are LEDs for the GATE and RESET
inputs, and the SET output of the latch.
The last bit of the circuitry is the two pots. These simply form voltage sources to a couple of
resistors. The current flowing through these resistors is added to the control nodes for the UP
and DOWN points in the MOTM-820. These allow the MOTM-820’s own pots to be used as
input attenuators whilst being able to set the absolute rise and fall times with the OMS-820.
Feel free to make any changes to the circuit to improve or alter the performance. If you do, do
visit the Oakley Sound forum on www.muffwiggler.com and tell us all what you have done.
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