ELECRAFT K1 - Appendix B K1 RF Board Schematic

Crystal Filter
Receive Mixer
Noise Blanker
K1 RF Board
Int. Speaker
Appendix B
W. Burdick
Attenuator
Headphones,
4.915 MHz
XFIL/TONE
XFIL/TONE
LM2930T-8
To FIL-P1
E.Swartz
RCV RF
LM380N-8
/AGC OFF
1 of 2
1N4148
1SV149
ZR78L06C
1SV149
Premix
AF Amp
BYPASS
MPSA14
SA602
SA602
SA602
100K
100K
MV209
220µF
220µF
10µF
2.2µF
0.01
6A
6A
6R/AUX
J309
.047
3300
1200
100K
RFC1
1200
680
100K
10µF
.047
1.5
Ω
C67
2.2µF
C66
C39
220
C38
220
C61
.047
C27
C26
C24
R16
R18
R17
C23
4:20, FT37-43
.01
C21
R14
RP1
RP1 RP1
C37
.01
C63
C65
330
C20
C19
C5
C41
RP2
VFO
D17
39
.047
75
120
75
2.7K
.01
.001
RP1
33 µH
R7
C40
.01
C25
.01
RP2
68
RP2
OUT
GND
4.4 µH
.01
C35
OUT
GND
5:20, FT37-43
39
C30
GND
IN1
IN2
GND
OUT
C33
12V
C31
AGC
R1
X3
U2
X1
X4X2
V-
V+
U1
V-
V+
U7
V-
V+
T1
K1
D6 D7
D8
22
X5
50
10 11 12
P1
13 14 15 16 17 18 19 20
Q8
C12
J2
P2
J1
C11
39
C7
C6
L1
D4
C2
D3
IN
U6
IN
U5
T2
J6
C10
V+
NC
U4
C9
1.8K
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
3
4
24
3
9
7
8
1
2
3
4
5
6
123456789
3
4
G
D
S
12
78
12345678
7
8
1
2
+
3
4
12345678
R23
+
1
2
3
45
6
7
8
+
+
Q2
+
Low-Dropout
8V Regulator6V Reg.
220
C42
/AGC OFF
12
J9
12
J10
Premix
PREMIX
To Rcv Mixer (via W1)
.01
C4
12V
R6
2.7K
POWER
RF/SMTR
6B
VFO POT
To FP-J1
VFO POT 6B
1
2
AGC (1.2VDC, no signal)
OFFSET
6B
1
2
PD2
PD1
-14 dB
Product Det./BFO
+
47K
RP3
Q1
6R/AUX
2N7000
RF/SMTR
C74
C72
C70
C71
C17
C18
RP3
34
RP3
2
1
.01.01
PD1
PD2
Q9
82
C8
KEYIN
R5
2.7K
2N3906
47K
47K
10
9
.01
.01
S
D
G
0.1
0.1
COUNTER
6R/AUX
*
the noise blanker is installed
RFC6
6A
6T 6R/AUX
Buffer
Q3
2N4124
C22
.001
RP6
4
3
27K
RP6
56
RP6
27K
2
1
C36
.01
D2
1N5711
100K
RP2
5
6
NOT USED
C32
.047
BYPASSIN1
IN2
OUT
GND
V+
G1
G2
1
2
3
45
6
7
8
U3
LM386N-1
Ext. Speaker
AF2
AF1
C69
220pF
RP3
6
5
47K
J309
Q11
G
S
D
8V
8V
C54
2.2µF
R21
2.7K
XFIL/TONE
D1
1N4148
RP3
7
8
47K
6B
6R/AUX
R13 2.2M
AF1AF2
C64
.01
(no signal)
+
AF Preamp/Mute
Q10
2N7000
S
D
G
1.0VDC
3.080 MHz when RF = XX.000 MHz
2.930 MHz when RF = XX.150 MHz
R2
6T
100K
100µH
R3
8.25K
C73
0.1
C34
0.1
10
R15
**
1%
C68
0.1
Elecraft
Rev. Sht. DateBy
G
RFC9
10 µH
Use 120 pF at C2 for ~150 kHz range
**
C22 must be removed when
*
12V_2
1/5/02