Edit: in the drawn PCB view the polarity of the unidentified protection diode was upside down, now it is corrected.
I replace it with a 1N4001 diode
I bought this defective Amiko NSG-2 noise gate pedal, it is identical in design to the PSK NSG-2 pedal.
Since I could not find a schematic, I drew it out by tracing the circuit board.
This pedal is a BOSS NF-1 noise gate clone.
Differences are:
External power supply through a DC adapter instead of a DC adapter.
C=47n instead of C=100n and R=470k instead of 220k behind the 1k resistor at the input.
The switching circuit has partly other values and the LED control has a new circuit.
The diode D8 of the original circuit is replaced by a bridge at the clone.
The SDT 1000 component is an NTC resistor with a value of 10 kiloohm.
By measurements at different temperatures I found out that this is also a NTC resistor.
The measured values correspond to the value of the data sheet excerpt below.
The transparent protection diode I measured see P/N junction curve below.
Now I can start the repair.
Amiko ( PSK) NSG-2 Noise Gate traced
- Manfred
- Tube Twister
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