225 Master Switch
225 Master Switch, from early 1988
The 225 Master Switch was introduced in 1988, and was initially marketed as a useful addition to the then-new DOD PRC-6 pedal road case. The 225 was derived from DOD's FX30B Gate/Loop pedal, using the same circuitboard (but with many fewer components). The key differences between the 225 and the FX30B are the 225's obvious lack of control knobs and noise gate capability, and that the location of the OUT and SEND jacks are switched. We have only seen a handful of 225 Master Switch pedals, but it appears the 225 had been discontinued by late 1991.
- Controls: none (just IN, OUT, SEND, and RETURN jacks)
- Operation of the 225 Master Switch can best be described by the graphic printed on top of the pedal, which shows how to use the 225 to switch one instrument between two outputs, to switch on/off a chain of effects pedals inserted into the 225's loop (SEND --> effects pedal chain --> RETURN), or to switch between two instruments to one output. The 225 can also serve as a buffer, as it is not true-bypass.
- Technical info:
- Specifications (probably the same as the FX30B): IN and RETURN impedance = 500 k Ohms, OUT and SEND impedance = 1 k Ohms
- Notable IC chip: LF353N op amp
- Component-side circuitboard image: March 1988
- Related circuit: FX30B
- Specifications (probably the same as the FX30B): IN and RETURN impedance = 500 k Ohms, OUT and SEND impedance = 1 k Ohms
- External links:
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