Ramsey Electronics FR6 manual PARTS LIST Inductors, Semiconductors and ICs, Special Components

practical level for speaker or headphone operation. Pin 16 of U2 will ground the input of U3 when the squelch is closed.

L4, a 450 KHz IF coil, permits adjustment of the 90-degree voltage-current phasing ("quadrature") of FL2's output to the FM detector demodulator (pin 8 of the MC3359).

PARTS LIST

Inductors

ˆ2 .15 uH inductors [looks like a resistor with brown-green-silver bands] (L1,L2)

ˆ1 slug-tuned turn coil [blue color] (L3)

ˆ1 shielded transformer coil [marked LB 53303] (L4)

Semiconductors and IC's

ˆ1 2SC2498 or 2SC2570A transistor (Q1)

ˆ3 2N3904 transistor (Q2,Q3,Q4)

ˆ1 SA602 8-pin IC (U1)

ˆ1 MC3359 18-pin FM receiver IC (U2)

ˆ1 LM386 8-pin audio amplifier IC (U3)

ˆ1 Varactor diode, BB505 [orange body marked BB505] (D1)

ˆ1 1N4148 signal diode (D2)

Special Components

ˆ1 10.24 MHz Crystal (Y1)

ˆ1 10.7 MHz ceramic filter [brown, molded, 3 leads] (FL1)

ˆ1 450 KHz ceramic filter [black, square] (FL2)

Fixed Resistors

ˆ1 2 ohm [red-black-gold] (R22)

ˆ3 270 ohm [red-violet-brown] (R6,9,20)

ˆ1 470 ohm [yellow-violet-brown] (R5)

ˆ2 1K ohm [brown-black-red] (R11,12)

ˆ3 10K ohm [brown-black-orange] (R7,17,19)

ˆ1 18K ohm [brown-gray-orange] (R18)

ˆ1 33K ohm [orange-orange-orange] (R14)

ˆ4 47K ohm [yellow-violet-orange] (R4,8,13,21)

ˆ1 100K ohm [brown-black-yellow] (R16)

ˆ1 470K ohm [yellow-violet-yellow] (R15)

ˆ1 1 megohm [brown-black-green] (R10)

Capacitors

ˆ1 4.7 or 5 pF (C2)

ˆ2 10 pF (C1,5)

ˆ1 22 pF (C19)

FR6 • 6