Ramsey Electronics FR6 manual FINAL CONNECTIONS THE LM386 AUDIO IC STAGE

Models: FR6

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70. Install C19, 22 pF.

71. Install Y1, the 10.24 MHz. crystal. No special procedure is required. Simply press the crystal firmly into its holes as far as it will go, and make good solder connections.

72. Install FL2, the 450 KHz filter. Its three leads are delicate and fit in only one way.

73. Install C23, .001 uF [marked .001, 102, or 1 nF].

74. Install C27, 1 uF electrolytic, observe correct polarity.

75. Install D2, the 1N4148 signal diode, observe correct orientation of the banded cathode end. Be sure you correctly identified D2 and did not confuse it with the varactor diode already installed.

76. Install R16, 100K ohms [brown-black-yellow].

77. Install R15, 470K ohms [yellow-violet-yellow].

5. FINAL CONNECTIONS: THE LM386 AUDIO IC STAGE

You now have a working FM receiver ready for adjustment. The output of the MC3359 FM IC simply needs to be boosted to listening level. A few more connections, and your receiver will be ready for adjustment and testing! Now would be a good time to review some of your previous work and also to make sure you have on hand what you'll need for testing: antenna, fresh battery, earphone or speaker with correct plug or adapter.

78. Review the instructions for installing U1 and U2. Insert the LM386 IC (U3) with the band or dot oriented correctly. Solder the 8 connections.

79. Install C32, a 100 to 220 uF electrolytic, observe correct polarity.

80. Install C31, .01 uF (marked .01, 103, or 10 nF).

81. Install C36, 4.7 or 10 uF electrolytic, observe polarity.

82. Install C33, 100 to 220 uF electrolytic, observe polarity.

FR6 • 16

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Ramsey Electronics FR6 manual FINAL CONNECTIONS THE LM386 AUDIO IC STAGE