Swann MARK II User manual
Price
$1.50
OPERATION
AND
MAINTENANCE
SAT
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ANNE
TSAI
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TRANSMIT
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LINEAR
AMPLIZIER
SWAN
MARK-IT
POWER
SUPPLY
SWAN
MARK
II
LINEAR
AMPLIFIER
ELECTRONICS
Oceanside,
California
A
Subsidiary
of
Cubic
Corporation
QS
WAN
Re
Treen
erie
ie
OR
Sa
ha
Ts
A
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Swan-Marn
i}
LINEAR
AMPLIFIER
Power
Rating:
2000
Watts
PEP
Input
in
Single
Sideband
Mode.
1000
Watts
DC
input
on
CW
AM
or
RT
TY.
5
Frequency
Ranges:
3,400
—
4,500
ke
6,000
—
9,000
ke
11,000
—
16,000
kc
16,000
—
22,000
ke
.
22,000
—
32,000
kc
Uses
two
Eimac
3-500Z
Grounded
Grid
Triodes.
CWP
Drive
Requirement:
100
Watts
for
maximum
legal
input.
Meter
Selector:
Reads
Plate
Voltage,
Plate
Current,
Grid
Current,
and
Relative
Output.
Includes
Transmit-Receive
Relay
Control
for
simple
operation
with
a
Transceiver.
Wide
range
Pi
Output
Circuit
matches
52
or
75
ohm
S.PEsGYF
ICA
TLONS:
SWAN
MARK-T
POWER
SUPPLY
coax
cable
or
variety
of
other
load
impedances.
Dimensions:
13"
wide
x
7"
high
x
12"
deep.
Weight:
20
lbs.
POWER
SUPPLY
Matching
unit
may
be
operated
next
to
Amplifier
as
illustrated,
or
with
its
4-1/2
foot
connecting
cable,
may
be
placed
on
the
floor.
Computer
grade
electrolytic
capacitors,
40
mfd.
fil-
tering
at
2500
VDC.
Silicon
Rectifiers.
AC
input:
117
or
230
volts,
50-60
cycles.
Includes
quiet
running
fan
for
cool
operation
of
all
components.
Dimensions:
9"
wide
x
8"
high
x
14"
deep.
Weight:
35
lbs.
S
Wi
4A
ELECTRONICS
Oceanside,
California
A
Subsidiary
of
Cubic
Corporction
CAUTION:
NEVER
REMOVE
THE
CABINET
OR
BOTTOM
PLATE
WHEN
POWER
LINE
VOLT-
AGE
IS
CONNECTED.
HIGHLY
LETHAL
VOLTAGE
IS
USED
IN
THIS
AMPLIFIER.
ALLOW
AT
LEAST
ONE
MINUTE
FOR
CAPACITORS
TO
DISCHARGE
AFTER
TURNING
THE
AMPLIFIER
OFF
AND
PULLING
THE
PLUG.
INSTALLATION
(d)
Connect
a
2
vonductor
line
from
auxiliary
(a)
Remove
the
amplifier
cabinet,
and
install
the
switching
contacts
on
the
driver
to
the
Relay
Con-
tubes.
They
should,
of
course,
be
handled
very
trol
jack
on
the
Mark
II.
When
using
the
Swan-
gently,
and
inserted
into
the
sockets
carefully.
250
as
a
driver,
the
2
conductors
connect
to
"C"*
Attach
the
plate
leads
firmly
but
carefully
to
and
"'T"
terminals
on
back
of
the
transceiver.
the
heat
dissipators.
Eimac
3-500Z
tubes
are
The
phono
type
plug
for
the
Mark
II
end
of
normally
being
supplied
with
the
Mark
IJ
ampli-
this
line
is
furnished
with
the
amplifier.
fier.
(e)
Connect
the
antenna
coax,
or
dummy
load
to
aR
ee
the
POEL
sup
Pps
cADKE
antenthe
A
gessometie
the
output
jack.
If
a
low-pass
filter
is
to
be
in-
amplifier,
and
install
the
High
Voltage
connec-
;
meme
stalled
to
reduce
TVI,
connect
it
between
the
out-
tor.
Be
sure
that
this
is
done
before
the
AC
pow-
;
3
"
:
put
jack
and
the
antenna.
er
supply
is
plugged
in.
(c)
Refer
to
the
pictorial
in
Fig.
1
when
making
the
(f)
Connect
a
ground
lead
to
the
Mark
II
Chassis.
installation.
Connect
a
short
length
of
coaxial
A
water
pipe
connection
or
ground
rod
will
be
cable
(RG-58
or
RG8)
from
the
transceiver
or
suitable.
exciter
to
the
coaxial
input
jack
on
the
Mark
II.
A
PL-259
typeconnector
is
required
atthe
ampli-
(g)
AC
power
line
connections.
The
Mark
II
power
fier
end
of
the
cable.
This
cable
should
be
as
supply
is
shipped
from
thefactory
with
terminals
short
as
practical
and
preferably
not
more
than
jumpered
for
230
volt
operation.
There
are
three
5
feet
long.
NOTE:
Swamping
the
exciter
or
wires
in
the
AC
power
cord.
driver
power
with
an
attenuator
is
not
normally
required
with
drivers
up
to
500
watt
PEP
input
rating.
After
proper
tuning
procedures
have
The
black
and
white
wires
connect
to
230
volts,
and
been
followed,
the
Mic.
Gain
control
will
be
used
the
green
wire
conn.
cts
to
the
neutral
or
ground
leg.
to
set
the
level
of
drive.
If
the
driver
is
called
A
3
terminal
AC
plug
will
be
required.
This
plug
on
for
less
than
its
maximum
power,
distortion
is
not
furnished
because
of
the
many
different
types
products
will
be
less,
and
overall
performance
being
used.
Therefore,
it
will
be
necessary
to
secure
improved.
a
plug
of
the
type
which
will
fit
your
230
volt
outlet.
JONES
PLUG
FUSES
BACK
OF
MARK
II
}
BACK
OF
SWAN
240
-
350
-
400
ANT
OR
500
(EER
(
ay
WZ
))
ae
ETRE
ASE
DREGE
EES,
Se.
Yq
RG-58
|
5
FT,
MAX
POWER
CABLE
PLO-PASS
TVI
|p
9
COAXIAL
(ce
aa
he
GROUND
WIRE
dear
rc
CABLE
TO
TO
WATER
PIPE
ANTENNA
OR
GROUND
ROD
ee
al
INSTALLATION,
REAR
VIEW
FIG.
1
INSTALLATION,
REAR
VIEW
BLACK
WIRE
To
my
te
BRASS
PRONG
r
GREEN
WIRE
TO
<—
TINNED
PRONG
(NEUTRAL)
=P
—~—e
WHITE
WIRE
To
BRASS
PRONG
3
COND.
POWER
LINE
CABLE
ied
From
MARK
IL
PowER
suppLy
‘
COMMON
TYPE,
ZIOVAC
PLUS
SLACK
WIRE
am
AX
TO
FLAT
PRONG
WHITE
WIRE
TO
FLAT
PRONG
)
S_
GREEN
WIRE
TO
GROUND
PIN
3
COND.
POWER
LINE
CABLE
FROM
MARK
IT
POWER
SUPPLY.
COMMON
TYPE
117
VAC
PLUG
WITH
GROUND
PIN.
FIG.
2
AC
PLUG
CONNECTIONS
For
117
volt
operation
of
the
Mark
II,
it
will
be
nec-
essary
to
change
jumpers
on
the
terminal
strip
in
the
power
supply.
Remove
the
power
supply
cabinet,
and
refer
to
Fig.
3
for
jumper
changes.
Replace
the
two
20
amp.
line
fuses
with
30
amps.
Connect
the
black
and
white
power
cord
wires
to
117
volts,
and
connect
the
green
wire
to
neutral
ground.
JUMPERS
FOR
230
VOLT
INPUT.
(AS
SHIPPED
FROM
FACTORY)
WARNING:
DISCONNECT
INPUT
POWER
CORD
BEFORE
REMOVING
CABINET.
FIG.
3.
POWER
SUPPLY,
TOP
VIEW.
NOTE:
When
the
Mark
II
is
operated
with
117
volt
AC
input,
current
drain
will
exceed
most
out-
let
ratings,
particularly
in
the
full
power
"SSB"
position.
It
may
be
necessary
to
operate
only
in
the
"TUNE-CW'"
position
in
order
to
reduce
power
drain
and
thus
keep
the
house
circuit
breaker
from
kicking
out.
If
it
is
necessary
to
operate
the
Mark
II
on
117
volts,
try
to
run
it
on
a
separate
circuit,
and
if
possible
on
the
oppo-
site
side
of
the
primary
house
circuit
from
the
side
used
for
the
rest
of
the
station.
Always
use
230
volts
for
the
Mark
II
whenever
possible.
JUMPERS
FOR
117
VOLT
INPUT
TUNING
INSTRUCTIONS
1.
Always
tune
the
exciter
or
transceiver
first,
with
the
Mark
II
turned
OFF.
Exciter
output
will
be
shunted
around
the
linear
amplifier
by
the
inter-
nal
relay,
and
will
go
to
whatever
antenna
or
load
is
connected.
The
"Output"
position
of
the
Mark
II
meter
circuit
will
indicate
exciter
output,
and
may
be
usedconveniently
as
a
tuning
meter.
Simply
adjust
the
exciter
controls
for
maximum
output,
usirg
whatever
tuning
procedure
is
pre-
scribed
for
the
particular
exciter.
Then
switch
the
exciter
back
to
standby
or
receive
position.
2.
Turn
the
Mark
II
function
switch
to
the
"TUNE-
CW"
position,
and
allow
several
seconds
for
filament
warm-up.
Leave
the
meter
switch
in
"Output"
position.
Set
the
bandswitch
to
proper
band
position
and
the
P.A.
Load
control
to
9
o'clock.
Illumination
of
the
meter
indicates
that
power
is
on,
and
the
tungsten
filaments
in
the
3-500Z
tubes
will
be
brightly
lit.
As
long
as
the
exciter
is
in"
Standby”
mode,
and
the
Relay
Con-
trol
circuit
:s
open,
the
3-500Z
tubes
are
biased
to
cut-off.
IP
and
IG,
(plate
current
and
grid
current,
respectively),
should
read
zero
when
tested.
EP,
(plate
voltage),
should
read
approxi-
mately
1600
volts,
depending
on
power
line
voltage.
3.
Turn
the
Mic.
Gain
down
on
the
exciter
(trans-
ceiver),
and
be
sure
the
carrier
has
been
bal-
anced
out.
Then
switch
the
exciter
to
normal
Voice-Transmit
position.
With
the
Swan
350
or
500
transce
ver
this
is
done
by
pressing
the
push-
to-talk
button.
If
the
relay
control
circuitry
is
properly
connected
and
functioning,
the
Mark
II
is
now
in
Transmit
mode,
and
the
red
indi-
cator
light
on
its
panel
willbe
on.
The
3-500Z
tubes
will
now
be
drawing
"idling
Current,"
so
IP
willread
about
.1
amps.
and
EP
will
be
about
1500
volts.
IG
should
still
read
zero.
4.
Switch
the
Exciter
to
its
"TUNE"
or
full
CW
power
position.
Quickly
adjust
P.A.
TUNE
on
the
Mark
II
for
maximum
output,
as
indicated
by
the
meter
in
Output
Position.
Then
go
back
to
the
Exciter
and
adjust
its
P.A.
TUNE
for
maximum
output.
(It
may
have
changed
slightly
when
switched
into
the
amplifier
cathode
circuit.
)
Next
advance
the
P.A.
LOAD
control
on
the
Mark
II
for
increased
output,
and
then
alternate
between
adjusting
P.A.
TUNE
and
P.A.
LOAD
until
the
highest
possible
output
indication
is
reached.
Set
the
Output
Level
Control
as
required
to
keep
the
meter
from
going
off
scale.
The
out-
put
reading
is
a
relative
indication,
only,
and
will
vary
considerably
with
different
antenna
loads
as
wll
as
with
frequency.
CAUTION:
DO
NOT
KEEP
THE
EXCITER
OR
TRANS-
CEIVER
IN
TUNE
POSITION
FOR
LONGER
THAN
30
SECONDS
AT
A
TIME.
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MARK
II
AMPLIFIER,
TOP
VIEW
FIG.
8
MARK
II
POWER
SUPPLY,
TOP
VIEW
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flmeny
4.
FIG.
7
MARK
II
AMPLIFIER,
BOTTOM
VIEW
tion
note
concerns
the
exciter
more
than
the
Mark
II,
but
since
the
3-500Z
power
amplifier
tubes
are
operating
at
full
input
during
tune,
the
time
should
always
be
kept
short.
If
longer
time
is
required,
switch
to
standby
for
a
minute,
and
then
back
to
TUNE
for
30
seconds.
With
experience
in
tuning
procedures,
it
will
be
found
that
30
seconds
is
more
than
enough
time.
Dial
Setting
5.5
Typical
dial
settings
on
Mark
II
when
coupled
to
a
50
ohm
non-inductive
load.
5.
After
tuning
all
controls
for
maximum
output
indication
as
described,
other
meter
readings
may
be
observed.
IG
(grid
current)
should
indi-
cate
.2
to.3
amperes
in
TUNE
position,
depend-
ing
on
the
amount
of
driving
power.
Swan
transceivers
will
generally
supply
more
driving
power
than
others
presently
on
the
market.
How-
ever,
most
transceivers
will
provide
enough
to
drive
the
Mark
II
to
full
legal
power.
IP
(plate
current)
should
indicate
at
least
.6
amps,
and
up
to
.9
amps,
depending-on
driving
power.
The
exact
values
of
grid
&nd
plate
current
are
not
critical
providing
they
do
not
exceed
.6
grid
amperes,
and
.9
plate
amperes,
and
this
only
during
short
tuning
periods.
.
SSB
Voice
Operation.
Having
followed
the
pre-
ceeding
tuning
procedures,
now
switch
the
Mark
II
to"SSB"
position,
and
its
meter
switch
to
"IP."
Apply
SSB
voice
exitation
from
the
transceiver
or
driver,
and
advance
its
Mic.
Gain
control
for
an
average
IP
reading
of
.40
amperes.
Only
occasional
voice
peaks
should
kick
up
to
.6
amps.
CAUTION
(1).
Exercise
great
care
in
setting
the
Mic.
Gain
control.
It
is
quite
easy
to
produce
higher
meter
readings,
but
flat-
topping
and
distortion
will
result,
as
well
as
the
possibility
of
exceeding
legal
power
limits.
CAUTION
(2).
Do
not
switch
the
exciter
into
"TUNE"
position
when
the
Mark
II
is
in
"SSB"
position.
Only
voice
modu-
lated
excitation
should
be
applied
in
this
position.
.
Monitoring
and
tuning
with
an
oscilloscope.
A
highly
recommended
piece
of
test
equipment
for
the
complete
amateur
radio
station
is
an
oscil-
loscope
suitable
for
monitoring
transmitter
out-
put
and
linearity.
This
instrument
will
permit
optimum
tuning
of
both
the
driver
and
amplifier,
as
well
as
continuous
monitoring
during
opera-
tion.
10.
Hy
An
excellent
oscilloscope
for
this
purpose
is
the
Heath
model
SB-610
sold
in
kit
form
by
the
Heath
Company
of
Benton
Harbor,
Michi-
gan.
The
instruction
book
supplied
with
this
kit
explains
in
detail
how
to
connect
and
use
the
instrument,
and
how
to
interpret
the
screen
pat-
terns.
Other
oscilloscopes
may
also
be
used.
The
Radio
Amateur's
Handbook,
published
by
the
ARRL,
and
the
Radio
Handbook
by
Bill
Orr,
published
by
Editors
and
Engineers
both
contain
detailed
information
on
the
use
of
os-
cilloscopes
for
transmitter
tuning
and
operation.
These
publications
are
recommended
references
for
this
purpose.
.
When
the
Mark
II
Function
Switch
is
in"SSB"
position
for
voice
transmission,
plate
voltage
is
increased
from
the
TUNE-CW
value.
In
Stand-
by
or
Receive
condition,
the
3-500Z
tubes
are
biased
to
cut-off,
so
IP
will
be
zero,
and
EP
will
indicate
2900
to
3000
volts,
depending
on
power
line
voltage.
In
TRANSMIT
position,
without
moduiativn,
IP
will
show
an
idling
current
of
.28
amperes,
and
EP
will
drop
to
2650
volts.
With
voice
modulation
averaging
.40
amperes,
EP
will
drop
to
about
2500
volts.
Occasional
voice
syllables
may
drop
the
plate
voltage
fur-
ther,
but
with
proper
setting
of
the
Mic.
Gain
control,
dynamic
regulation
of
the
power
supply
is
more
than
adequate.
Use
of
computer
grade
electrolytics
assures
long
capacitor
life,
with
a
filter
capacity
of
40
mfd.
across
the
plate
supply.
(All
voltage
readings
above
are
subject
to
line
voltage
variations).
.
To
operate
without
the
Mark
II
Linear
Ampli-
fier,
simply
switch
it
to
"Power
OFF"
position.
The
antenna
circuit
is
then
by-passed
around
the
amplifier
by
the
internal
relay
and
the
trans-
ceiver-driver
will
operate
"Barefoot".
When
switching
back
to
amplifier
use,
allow
a
few
sec-
onds
for
filament
warm
up.
CW
Operation.
To
operate
CW
with
the
Mark
II
always
keep
the
Function
Switch
in
the
TUNE-
CW
position
in
order
to
limit
input
power
to
1000
watiz.
CAUTION:
Because
the
Mark
II
uses
a
grounded
grid
amplifier
circuit,
input
power
measurements
must
include
the
driver
stage
input.
If
for
example,
the
driver
is
run-
ning
300
watts
input,
the
linear
amplifier
input
must
be
limited
to
700
watts
when
in
CW
Mode.
Thus,
ycu
must
first
measure
driver
input,
in
order
to
determine
how
much
input
you
may
run
to
the
Mark
II.
Use
the
EP
meter
position
to
measure
plate
voltage,
and
then
calculate
how
much
IP
(plate
current)
you
can
run
and
stay
within
the
legal
limit.
Then
use
the
P.A.
Load
control
to
hold
IP
down
to
this
level.
AM
Operation.
The
Mark
II
Linear
Amplifier
may
be
operated
in
the
"AM"
mode
at
1000
watts
D.C.
input
and
100
percent
modulation.
When
using
a
transceiver
or
exciter
which
will
7
123
13.
also
operate
in
the
SSB
mode,
first
tune
the
transceiver
and
Mark
II
for
SSB
transmission,
just
as
described
in
previous
instructions.
Then
insert
carrier
in
accordance
with
instructions
furnished
with
the
exciter.
With
Swan
Trans-
ceivers,
this
is
explained
in
tuning
instructions
under
"AM
operation."
If
the
exciter
operates
only
in
the
AM
mode,
it
is
recommended
that
an
oscilloscope
and
an
audio
oscillator
be
used
for
proper
adjustment.
Feed
an
audio
tone
of
about
1000
cycles
intothe
Mic.
Jack
of
the
exciter
and
couple
the
vertical
input
of
the
scope
loosely
to
the
output
of
the
Mark
II.,
Switch
the
exciter
to
Transmit
mode
and
adjust
its
modulation
level
to
approximately
90%.
Then
adjust
P.A.
Load
and
P.A.
Tune
Controls
on
the
Mark
II
for
optimum
output
with
minimum
flat-
topping
of
the
modulation
envelope.
Next,
remove
modulation
and
check
the
total
power
input
with
carrier
only.
It
should
not
exceed
the
legal
1000
watt
limit.
Reduce
coupling
from
the
exciter
as
required
to
control
input.
CAUTION:
It
is
quite
possible
to
run
well
in
excess
of
the
legal
power
limit
on
CW
as
well
as
SSB
with
the
Mark
II.
The
design
of
an
amplifier
with
excellent
linear
characteristics
up
to
the
legal
limit
results
in
this
capability.
The
burden
of
operating
within
legal
limits
falls
on
the
operator
and
Swan
Electronics
Corporation
is
not
responsible
for
improper
or
illegal
opera-
tion.
Every
well
informed
operator
should
be
familiar
with
measurement
procedures,
and
with
mathematical
calculations
of
power
level.
When-
ever
possible,
an
oscilloscope
should
be
used
to
monitor
peak
power
levels,
since
ordinary
meters
are
unable
to
do
so.
RTTY
Operation.
The
Mark
II
is
rated
at
a
minimum
of
800
watts
continuous
input
power
for
RTTY
service.
The
full
legal
limit
of
1000
watts
may
be
run
for
periods
up
to
1
hour
or
longer
when
ventilation
is
adequate.
Tempera-
ture
rise
of
the
power
transformer
is
the
main
limiting
factor,
and
it
is
limited
to
a
maximum
of
105°
C
Tuning
procedures
when
using
FSK
or
AFSK
are
essentially
the
same
as
when
tuning
for
CW
operation.
Care
must
be
observed
in
order
to
hold
input
power
to
the
legal
limit.
For
con-
tinuous
operation,
it
is
important
that
adequate
ventilation
be
provided.
In
a
confined,
relatively
warm
environment,
the
equipment
will
natu-
rally
run
hotter,
and
additonal
ventilation
from
an
auxiliary
fan
may
be
advisable.
Normally,
however,
this
will
not
be
required.
Temperature
rise
is
the
sole
criterion.
Alternate
Tube
Types.
Although
the
Mark
IT
is
now
manufactured
for
use
with
the
Eimac
3-500Z
tubes,
it
may
also
be
operated
with
the
type
3-400Z.
Power
ratings
will
be
the
same.
Either
tube
type
will
operate
easily
at
the
legal
power
limit.
The
3-500Z's
are
supplied
with
the
Mark
II
because
of
the
added
safety
factor
in
the
higher
dissipation
rating.
Two
changes
are
re-
quired
to
use
the
3-400Z's.
First,
the
plate
caps
must
be
changed,
and
since
the
type
needed
for
the
3-400Z
is
supplied
by
Eimac
with
the
tubes,
this
should
present
no
problems.
Second,
the
4
diodes
connected
in
series
with
the
filament
center-tap
circuit
must
be
jumpered.
These
diodes
are
the
large
stud
mounted
type
located
on
a
terminal
board
under
the
amplifier
chassis.
Their
zener
characteristic
is
used
to
supply
approx.
4
volts
of
bias
required
by
the
3-500Z's.
Simply
connect
a
jumper
wire
around
them
if
3-400Z's
are
to
be
used.
MAINTENANCE
(a)
The
3-500Z
tubes
will
show
little
or
no
color,
due
to
the
carbon
plate
and
higher
plate
dissipa-
tion
rating.
(b)
The
Amplifier
Function
Switch
is
no
longer
vul-
nerable
to
damage
because
it
no
longer
switches
the
H.V.
directly,
but
switches
the
relay
K3
in-
stead.
(c)
K2
is
now
a
highly
reliable
Mercury
relay
and
burnishing
is
no
longer
necessary
or
possible.
There
will
be
litle
maintenance
required
in
the
Mark
II
amplifier.
The
3-500Z
tubes
will
provide
thou-
sands
of
service
hours
when
operated
according
to
instructions.
Deterioration
of
a
tube
will
generally
be
indicated
by
a
change
in
idling
current
or
inabil-
ity
to
draw
normal
plate
current,
or
both.
However,
except
for
oc-
casional
field
problems
which
may
occur
with
any
electronic
device,
the
tubes
may
beexpected
to
operate
month
after
month
and
year
after
year
withno
prob-
lems.
NOTICE
—
Ifwarranty
replacement
is
required,
the
tubes
must
be
shipped
to
the
tube
manufacturer
with
a
comple!:
failure
report.
Do
not
ship
them
to
your
dealer
or
to
Swan
Electronics
as
this
will
only
delay
warranty
adjustments.
Other
components
are
also
operated
conservatively,
and
well
within
nominal
ratings.
The
electrolytic
filter
capacitors
in
the
power
supply
are
computor
grade,
meaning
that
they
have
a
much
higher
degree
of
purity
and
quality
control
than
conventional
types.
Life
expectancy
of
these
filters
is
approxi-
mately
10
years.
The
silicon
diodes
used
in
the
sup-
ply
are
hermetically
sealed
and
are
not
likely
to
ever
fail
or
wear
out.
They
are
rated
at
600
PIV,
1
ampere.
The
blower
motors
are
lifetime
lubricated
and
like-
wise
are
not
expected
to
require
maintenance
of
any
kind.
CAUTION:
DUE
TO
THE
USE
OF
A
MERCURY
RELAY
(K2),
THE
POWER
SUPPLY
MUST
BE
SITTING
IN
A
NORMAL
UPRIGHT
POSITION
BEFORE
CONNECTING
OR
PLUGGING
IN
POWER
CORD.
THE
MERCURY
RELAY
MAY
CLOSE
ACCIDENTALLY
IN
ANY
OTHER
POSITION.
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