Elenco FM Wireless Microphone Kit - Manual (Page 3)

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FM MICROPHONE KIT
Your FM Microphone is really a miniature frequency
modulated transmitter operating in the standard FM
broadcast band. The range of frequencies for the
FM broadcast band is 90MHz (MHz = Megahertz or
90 million cycles per second).
Because the FM
microphone has a variable tuned circuit, it can be
tuned to a quiet spot on your local FM broadcast
band for the best reception.
When the small
microphone element is struck by sound, it converts
the audio to a change in current through resistor R1
(see schematic diagram). This electrical change is
amplified and eventually frequency modulates the
transmitter.
The transmission range of the FM
microphone is approximately 100 feet, depending
on the efficiency of the antenna (properly tuned or
not) and the quality of the FM radio receiver.
IDENTIFYING RESISTOR VALUES
Use the following information as a guide in properly identifying the value of resistors.
BAND 1
1st Digit
Color Digit
Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Gray 8
White 9
BAND 2
2nd Digit
Color Digit
Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Gray 8
White 9
Multiplier
Color Multiplier
Black 1
Brown 10
Red 100
Orange 1,000
Yellow 10,000
Green 100,000
Blue 1,000,000
Silver 0.01
Gold 0.1
Resistance
Tolerance
Color Tolerance
Silver +10%
Gold +5%
Brown +1%
Red +2%
Orange +3%
Green +0.5%
Blue +0.25%
Violet +0.1%
BANDS 1 2 Multiplier Tolerance
IDENTIFYING CAPACITOR VALUES
Capacitors will be identified by their capacitance value in pF (picofarads), nF (nanofarads), or
µ
F (microfarads). Most
capacitors will have their actual value printed on them. Some capacitors may have their value printed in the following
manner. The maximum operating voltage may also be printed on the capacitor.
Second Digit
First Digit
Multiplier
Tolerance
The letter M indicates a tolerance of +20%
The letter K indicates a tolerance of +10%
The letter J indicates a tolerance of +5%
For the No. 0 1 2 3 4 5 8 9
Multiply By 1 10 100 1k 10k 100k 0.01 0.1
Multiplier
Note: The letter “R” may be used at times
to signify a decimal point; as in 3R3 = 3.3
103K
100V
Maximum Working Voltage
The value is
10 x 1,000 =
10,000pF or
.01
µ
F 100V
1
0
µ
F
1
6
V