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Copyright
2008 FiveFish Studios
www.fivefishstudios.com
SC-1mk500 Microphone Preamp Kit
All of the electrolytic capacitors used in the SC-1mk500 preamp have polarity, except the (2) blue electrolytic capacitors. 10uf
50V NP, shown on the picture on the right. These (2) electrolytic capacitors, labeled C12 and C13, are Non-Polarized, so it does
not matter how you insert them. But the rest of the capacitors in the SC-1mk500 kit should be inserted in the proper polarity.
Diodes
Diodes are semiconductor devices that permit current flow only in one direction. Think of it as a
one-way valve.
The SC-1mk500 preamp kit uses 3 different kinds of diodes.
1.
The first type of diode we’re using is the ZENER DIODE. These zener diodes are used as
input protection to the mic preamp circuitry. You can find the zener diodes in the
locations shown on the photo to your right.
PLEASE NOTE
: Even though the SC-1mk500 preamp uses input protection, please turn OFF
phantom power, and wait a few seconds (5-10 seconds) before unplugging your microphone.
Also, do not plug a mic while phantom power is ON. If you’re using the SC-1mk500 with TRS jacks connected to a patch
bay or another gear, do not turn ON phantom power… NEVER, EVER plug a jack into a patchbay with Phantom Power turned
ON. You risk of damaging any gear connected at the other end of the patch bay and may even possibly damage your
preamp. In short, turn OFF phantom power before connecting/disconnecting the microphone and/or jack. It takes only a
few seconds to do this. Don’t risk damaging your gear.
2.
The second type of diode we’re using is the SIGNAL DIODE. They look almost exactly like
the Zener diodes. Nothing to worry about, I packed the Signal Diode in a separate Zip bag
for easy identification.
3.
The third type of diode we use is the General Purpose, Rectifier Diode. They are black, with
a white/silver band.
NOTE: Diodes have polarities just like electrolytic capacitors. One side is
denoted as the ANODE (or positive side) and the other side is the
CATHODE (or negative side). If you soldered these diodes in the wrong
position, your phantom power or preamp may not work. Follow the band
markings on the PCB silkscreen layout.
Inductors
The SC-1mk500 Preamp kit also uses inductors for RFI protection in the output stage. Inductors have no polarities, and just like
resistors can be inserted in either orientation. The inductors we use look just like resistors. For your convenience, they are
packed in a separate zip bag and labeled.
