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Copyright
2008 FiveFish Studios
www.fivefishstudios.com
SC-1mk2 Microphone Preamp Kit
Transistor
We’re using a transistor as a switching device in the SC-1mk2 Mic Preamp Kit. The transistor has (3) legs, the Collector, Base and
Emitter terminals. Looking from the top, the transistor has a half-circle shape, like a half-moon.
Take note when inserting transistors that you do not insert them backwards. Otherwise, phantom power will not work, and
possibly even ruin the transistor. The flat side should be facing to the right.
Grayhill Selector Switch
The SC-1mk2 uses a sealed, high-performance, high-quality,
12-position, Grayhill selector switch. This is one of the most
expensive items in this kit.
Some boutique preamp manufacturers also use Grayhill selector
switches for their preamps. They are durable, reliable, have a
nice solid feel to it, and provide good resistance to RF
Interference. This switch will be the most commonly
used/abused mechanical device on the SC-1mk2 preamp. I want
this part to withstand being turned and turned and turned.
DPDT Switch (Dual Pole, Dual Throw.)
The SC-1mk2 also use a high quality, PCB mounted DPDT switch.
This is another one of the expensive items in the kit. Again, since
this is a mechanical device, I want it to withstand repeated use of
toggling on and off.
You need to toggle the switch to the leftmost position (pointing
to the LED) to turn on phantom power. If you mount the SC-
1mk2 PCB vertically, the switch will be turned ON pointing
upwards. If you mount the SC-1mk2 PCB horizontally, the switch
will be turned ON pointing left, towards the LED.
Bourns Sealed Potentiometer
This is another high-priced item in this kit because it is another
mechanical component and I want this part to withstand the use
and abuse of being rotated constantly. I want it to provide a
smooth feel, and not wore out easily, and become “scratchy” like
a cheap, carbon potentiometer. I want it to have a longer life
than plain “guitar potentiometers.” This is also sealed from the
elements so dirt, grime, oil, and impurities will not contaminate
the resistive element and produce a “scratchy” volume control.
The resistive element inside is made of conductive plastic. Unlike
carbon potentiometers, these will last a very long time even after
repeated rotations.
