Elenco Snap Circuits® Deluxe Sound & Light Combo - Manual (Page 108)

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In this project you will listen to the keyboard sound both with
and without echo, at the same time (in stereo). This project
requires stereo headphones or a stereo speaker; neither is
included with this set, but this set does include a stereo
cable to help connect to your stereo speaker.
Build the circuit as shown; note that the 5.1kW resistor (R3)
is a tight fit over the adjustable resistor (RV) but does fit.
Connect your own headphones or stereo speaker to the
audio jack (JA). Turn on the slide switch (S1).
Press keys on the keyboard (U26), and listen to the sound
on your headphones or stereo speaker. One ear (or side of
the speaker) hears the keyboard directly, set RV3 for most
comfortable sound level (turn to the left for higher volume,
most of RV3’s range will be very low volume). The other ear
(or side of the speaker) hears the sound with echo; adjust
the amount of echo using the lever on the adjustable resistor
(RV). Try this at different RV settings, because the effects
are very interesting with both high and low echo amounts.
If the echo sound is not loud enough then add the 1mF
capacitor (C7) next the echo IC (U28) as shown here:
For best effects, try to set RV3 so that the sound level is
about equal on both sides of the headphones/speaker.
Headphones or Stereo
Speaker (not included)
WARNING: Headphones performance varies, so use caution. Start with
low volume, then carefully increase to a comfortable level. Permanent
hearing loss may result from long-term exposure to sound at high volumes.
!
Project 216
The 100W and 5.1kW resistors (R1 &
R3) make the keyboard signal smaller,
otherwise it would be distorted by the
amplifier in the echo IC.
Keyboard Echo with
Stereo Effects
SCC-350_Manual_Part_B.qxp 7/25/14 2:06 PM Page 52