Data Sheet

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194. Capacitor Tolerance

Build the circuit shown on the left and turn on the switch (62). Press

the press switch (61) and you will see the heart LED (69), star LED

(70), and colorful LED (72) light. Release the press switch (61) and the

heart LED (69), star LED (70), and colorful LED (72) will stay bright for

a while and then turn dim.

Capacitor tolerances usually are not marked because most capacitors

have a tolerance of ±20%. So the actual capacitance of the 470mF

capacitor (74) should be between 0.8*470 = 376mF and 1.2*470 =

564mF.

195. Capacitor Operating Temperature

Replace the 1kW resistor (42) in project #194 with the 5.1kW resistor

(43) and then turn on the switch (62). Press the press switch (61) and

you will see the heart LED (69), star LED (70), and colorful LED (72)

light. Release the press switch (61) and the heart LED (69), star LED

(70), and colorful LED (72) will stay bright for a while and then turn dim.

If you look closely at the 470mF capacitor (74) you will see that it is

marked as –40 to +105

C. This is the temperature operating range for

this part. Outside this temperature range the actual capacitance may

be outside the ±20% that is typical.

196. Ceramic Capacitors

Replace the 1kW resistor (42) in project #194 with the 10kW resistor

(44) and then turn on the switch (62). Press the press switch (61) and

you will see the heart LED (69), star LED (70), and colorful LED (72)

light. Release the press switch (61) and the heart LED (69), star LED

(70), and colorful LED (72) will stay bright for several seconds and then

turn dim.

Even though the capacitors in your Circuit Blox™ 395 set are polarized,

not all capacitors are polarized. Small capacitance capacitors (typically

1mF or less) are often ceramic capacitors that do not have polarity.

Ceramic capacitors use a ceramic material as the dielectric between

the two plates.

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