Heathkit W-5M User Manual

( )
Snap the top
cover in
place by
lining
the cover studs up
with the
appropriate holes in
the
chassis
and
pressing
down
gently
on
all four corners
until firmly settled.
This
completes
the
assembly
and
adjustment of your Heathkit
Amplifier
model
W-5M.
SeePage
27
for
Installation
and
Operation.
IN CASE OF
DIFFICULTY
Recheck
the
wiring. Trace
each
lead
in colored
pencil on
the
pictorial
as
it is checked
in
the
amplifier.
Most
cases
of difficulty
result from
wrong
connections.
Often having a
friend
check
the
wiring
will
reveal a mistake
consistently
overlooked.
If
possible,
compare the
tube
socket
voltages
with those
shown
in the voltage table
below.
Read-
ings
within
20%
of those shown
may be
considered
as
normal. If a
discrepancy is noted, check
the
associated circuits
carefully.
Any
component in
those circuits
should
be
suspected
until
proven
satisfactory.
If
voltages and
tubes
are
normal,
try the
following
procedure.
With
the preamplifier
output
disconnected
from the amplifier
input, touch tube socket
terminal
V4-5
with one lead
of
a
.01
jafd
condenser,
holding
the
other lead in
your
hand.
(CAUTION:
Do
not touch the
chassis
or
any
other metallic
body with
your
other
hand
while making this test
.
Dangerously high
voltage
is present
throughout the circuit
and
due
care
should
be
exercised.
)
This
should
cause a
hum
level
to be
evident
in the
speaker,
if the
circuit from
this point
is
nor-
mal.
Work
on
forward
in the circuit,
touching
terminals
V3-5,
V2-6, V2-7, V2-1, V2-2,
Vl-8,
VI
-6,
VI
-7,
VI
-1
and
VI
-2. The hum
level
should increase
somewhat
as
you
work
back toward
the amplifier input.
At
some point
in
the
amplifier, the
circuit
will
appear
to be dead
and
all
circuitry
following that stage may be
disregarded
in your trouble
shooting.
In
this
way,
you can
easily
locate the
source
of the trouble
and expedite
its correction.
VOLTAGE
CHART
SOCKET
TUBE
TYPE
Pin 1
Pin
2
Pin 3
Pin
4 Pin 5
Pin 6 Pin
7
Pin
8
Pin
9
VI
12AU7
88
NS
2.2
Fil.
280
88 100
Fil.
V2
12AU7
255 NS
13
Fil. 255
NS
13
Fil.
V3
KT66
TP
47
Fil.
480
480
*8.3
TP
485
Fil. 50
V4
KT66
TP
12.5
Fil.
475
480
*6.7
TP
480
Fil.
50
V5
5R4GY
NC
**
510
TP
495
455
VAC
TP 310
455 VAC
TP
240
**
510
AA
POWER
Fil.
Fil. 0
400
300
110
VAC
Switch
Circuit
G
CONDENSER
a 380
400 . 350
H
CONDENSER
a
235 m
245
All
voltages
positive
DC
to
chassis,
measured
with
Heathkit
V-7 VTVM
with
11
megohm
input
resistance.
Voltages
taken
with Heathkit
WA-P2
Preamplifier
connected.
TP
-
Tie
point.
NS
-
Not
significant. Line voltage
-
117
volts
AC.
Fil.
-
Voltage
between
points
so
designated, 6.3
volts
AC.
*
Voltages so
designated
will
vary with
changes
of
settings
of Bass-Bal
control.
**
Voltages
between
pins
8
and
2-5
volts
AC.
Page
25

Heathkit W-5M Specifications

General

Brand	Heathkit
Model	W-5M
Category	Amplifier
Language	English