Heathkit SB-401 - Page 86

a
NOTE: FILTER RESISTANCE MAY MEASURE VERY LOW,
3
305MHZ
BUT
THESE
MEASUREMENTS
ARE
NOT
MEANINGFUL.
ve
eases.
=]
YS
saunter
TRANSFORMER
|
SAVE
Peet
aM
RATION
MB:
va
6.395
-8.895MHZ
6GEW6
3.39SMHZ
CRYSTAL
FALTER
LMO MIXER
e302
100 PF
azog_|ceis
ipl
cele csor
isorr Bag
DRIVER
Tot
ORG
WHT=GRN
7 acc!
METER SWITCH
LMO MODE
Masren
SHOWN
IN
OSCILLATOR
INTERNAL
7
LMO
POSITION
(SEaLeo
UNIT)
ouTpuT
v6
6826
(SEE SCHEMATIC
THIS PAGE)
4R
HETERODYNE OSC. COILS
29.5
Seon. oS
on
4000
7W
8
ol
ats
oe:
w
:
do
[ate
se
aF
g
T*
roeetes
car
O_
=
eePr
OgraD
x om 10 Gye
38 Oy G)
tok.
FARR, sin 35
ia
ba
ae
C39
cae
TOOPF
Tors
RED =
WHT- VIO RFCIO aa
RCVR. HET.
OSC. AMP.
HET. OSC.
INPUT aua-viou
GRN
GRN
29.0 28.0
iy DRIVER GRID COILS
WHT-GRN
WHT,
VBA
\72 6AWB
HET.
WHT-GaN
ALC INPUT
osc
15.895 MHZ 12.395 MHZ
37.895MHZ 37.305 MHZ
4 iT] 22.895MHZ
HET. OSC.
TEST POINT
WHT-VIOQL
VIL
Gaay
WHT-GRN,
CRN
PEC. 84-22
RCVR
MUTE
LINEAR
RELAY
HT-GRAY
ICTION.
rN
TRAN
5 SPOT
1
|
|
|
|
|
'
~ (
'
~“
SCHEMATIC OF THE
HEATHKIT®
SSB TRANSMITTER
MODEL SB-401
x
NOTES:
nN
RESISTOR
AND
CAPACITOR
NUMBERS
ARE
IN
THE
FOLLOWING
GROUPS:
0-99
100-199
200-299
300-399
400.499
PARTS MOUNTED ON THE CHASSIS
PARTS
ON
THE
CARRIER
GENERATOR
CIRCUIT
BOARO
PARTS
ON
THE
MIXER
BANDPASS
CIRCUIT
BOARD
PARTS
MOUNTED
ON
TERMINAL
BOARD
©1
PARTS MOUNTED ON TERMINAL BOARD 72
ALL
RESISTORS
ARE
1/2
WATT
UNLESS
MARKED
OTHERWISE,
RESISTOR
VALUES
ARE
IN
OHMS
| K
=
1000,
M
=
1,000,001,
ALL
CAPACITOR
VALUES
ARE
IN
fd
UNLESS
MARKED
OTHERWISE.
ALL
SWITCH
WAFERS
SHOWN
IN
FULL
COUNTERCLOCKWISE
POSITION,
AS
VIEWED
FROM THE KNOB END OF THE SHAFT.
OF SOME SWITCHES INDICATES A TIE PIN WHICH
THE DOT LOCATED IN THE CENTER
TS ON THE OTHER SIDE
CONNECTS
A
CONTACT
ON
ONE
SIDE
OF
THE
ROTOR
TO
CONTAC
OF
THE
SAME
ROTOR.
SWITCH
WAFERS
ARE
IDENTIFIED
AS
IN
THE
FOLLOWING
EXAMPLE:
8
(BAND!
eb
iF
WAFER
NUMBER
WITH
THE
SWITCH
VIEWED
FROM
THE
FRONT
PANEL.
REFER
TO
THE
CHASSIS
PHOTOGRAPHS
AND
CIRCUIT
BOARD
X-RAY
VIEWS
FOR
THE
PHYSICAL
LOCATION
OF
PARTS.
F = FRONT SIDE OF THE WAFER.
R = REAR SIDE OF THE WAFER.
FRONT PANEL
NAME OF
SWITCH.
RELAYS ARE SHOWN IN STANDBY POSITION.
# IDENTIFIES SECTIONS OF ALI
VOLTAGES
AND
RESISTANCE
MEASUREMENTS
LISTED
ON
CHARTS
BEGINNING
ON
PAGE
145
OF
MANUAL.