CIRCUIT
DESCRIPTION
300-VOLT
LINE
To
minimizevariationsandrippleinthe
line,
a
silicon
bridgerectifier
circuit
andchalkinput
system
areemployedforthe300-voltB
line.
210-VOLT
LINE
Resistors
areplacedinseriesbetweenthe300-volt
line
andthe210-voltlineforthepurposeof
droppingthevoltage.
150-VOLT
LINE
If
the150-voltlinevoltagedropsduetoa
varia-
tion
ofload,thegridvoltageonthetriodsideof
V2oi
6BM8
will
alsodrop.
This
causestheplate
currenttodecrease,sincethecathodvoltageis
fixed.
When
theplatecurrentdecreases,thevoltage
drop
acrosstheR201470Kftbecomesless,
while
the
platevoltage
tends
torise.Accordingly,thegrid
biasonthe
pentode
sideof
6BM8
tends
tode-
crease,therebystabilizingthe150-volt
output
at
theoperatingpoint.
This
output
voltagecanbe
varied
byadjustingthe
VRi
half-fixed
resistor.
(-)
C LINE
FOR
BIAS
The
half-wavecurrentissuppliedtothe(-)C line
for
thebiasthrougha
silicon
diode.
12.6-VOLT
LINE
To
supplyheatervoltages,thepowertransformer
hastwo12.6-voltsecondarywindings;
that
is,
one
for
the
final
S2001
x 2 line
exclusively
forthe
transceiver
andtheotherforothervacuumtubes.
Taking
intoconsiderationa possiblevoltage
drop
atthepowersupplycordbetweenthePS-510and
the
TS-510,
thetransformerisprovided
with
two
13.5-volt
windings.
63-VOLT
LINE
A
6.3-voltwindingisusedforheatingthe
6BM8.
To
preventthebreakageoftheinsulationbetween
the
cathode
heaters,thiswindingisapplied
with
a
voltageof+150V.
SPEAKER
TERMINALS
The
powersupply
jack
incorporatesspeakerline
terminals.
Theon-offpower
switch
isattachedto
thetransceiver.Partofthelead
wire
tothetrans-
formerprimarywindingisconnected
with
the
powersupplysocket.
This
enablestheoperatorto
turnonoroffthemachinefromthetransceiver
side.
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