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TROUBLESHOOTING
Contact Elenco Electronics if you have any problems. DO NOT contact your place of purchase as they will not
be able to help you.
1. One of the most frequently occurring problems is poor solder connections.
a) Tug slightly on all parts to make sure that they are indeed soldered.
b) All solder connections should be shiny. Resolder any that are not.
c) Solder should flow into a smooth puddle rather than a round ball. Resolder any connection that has
formed into a ball.
d) Have any solder bridges formed? A solder bridge may occur if you accidentally touch an adjacent foil
by using too much solder or by dragging the soldering iron across adjacent foils. Break the bridge with
your soldering iron. (See Figure K).
2. Be sure that all components have been mounted in their correct places.
a) Be sure that the electrolytic capacitors C5, C8 and C9 have been installed correctly. These capacitors
have polarity, so the negative and positive leads must be in the correct holes as marked on the top
legend side of the PC board.
b) Be sure that the LEDs are mounted as shown in Figure F.
c) Be sure that the integrated circuits U1 and U2 are mounted with the notches in the same direction as
marked on the PC board.
d) Be sure that the speaker SP1 is mounted with the positive (+) lead in the correct hole as marked on the
PC board.
e) Be sure that the power cord has been installed correctly. The red wire goes to the pad marked J2 and
the black wire goes to the pad marked J3. (See Figure K).
f ) Be sure that the diodes are mounted with the band in the same direction as marked on the PC board.
Foil Side of PC Board
Figure K