Gonset G-66 - Operational Features; Muting; Transmitter Frequency Spotting; Electrical Noise Suppression

If a power supply other than the No. 3069 or
3098
is
used
it
must
be
well
filtered
both
for
ripple
and
r-f
hash
and
be
capable
of
delivering
190
to
220
volts
at
80
ma
under
continuous-service
conditions.
The
output
filter
capacitor
must
be
at
least
30
mfd
to
provide
a
sufficiently
low
impedance
audio
return
path,
A
smaller
capacitor
may
cause
audio
feedback
within
the
receiver,
MUTING
ns
are
made
for
muting
the
receiver
during
ing
periods,
By
removing
the
strap
between
terminals
1
and
2
of
the
power-supply
terminal
strip
and
connecting
these
terminals
to
contacts
on
the
T/R
relay,
plate-supply
voltage
to
the
receiver
is
intercupted
during
transmission,
Use
well-insulated
wire
for
these
leads
and
make
certiin
that
the
con-
nections
at
the
tern
strip
do
not
short
to
the
power-supply
case.
Also
be
sure
to
replace
the
pheno-
lic
safety
cover
over
the
terminal
strip
after
connec-
tions
are
made.
The
T/R
relay
contacts
used
for
muting
must
be
capable
of
breaking
200
volts
at
100
ma,
If
necessary,
a
spark
arrestor
consisting
of
a
0.1
mfd
capacitor
in
series
with
a
270-ohm
resistor
may
be
connected
across
the
relay
contacts
to
suppress
sparking.
This
muting
method
effects
a
considerable
saving
in
battery
power
while
transmitting.
However,
it
will
be
found
that
the
receiver
local
oscillator
drifts
slightly
between
receiving
periods
since
che
oscillator
tube
cools
during
the
time
when
plate
voltage
is
removed,
The
drift
is
noticeable
only
when
receiving
SSB
and
CW
signals
on
the
high-frequency
bands.
If
a
considerable
amount
of
this
type
of
reception
is
planed,
an
alternate
muting
method
is
advisable.
Connect
terminals
3
and
4
of
the
power-supply
termi-
nal
strip
to
T/R
relay
contacts
that
make
during
transmission,
Do
not
remove
the
strap
between
terminals
1
and
2,
This
method
shorts
the
speaker
voice
coil
during
transmission
and
is
very
effective
provided
that
fairly
heavy
wire
is
used
for
the
con-
nections
and
the
total
length
is
not
excessive.
TRANSMITTER
FREQUENCY
SPOTTING
The high voltage available at terminal 1 of the
power-supply
terminal
serip
may
be
used
to
operate
a
tra
ter
VFO
through
a
“spot”
switch
if
de-
sired.
A
maximum
of
25
ma
may
be
drawn
for
this
purpose
for
short
periods
without
harm
to
the
power
supply.
ELECTRICAL NOISE SUPPRESSION
The G-66 receiver contains a highly-effective noise-
limiting
circuit,
Nonetheless,
for
optimum
perform-
ance
it
is
important
that
electrical
noise
generated
by
vatious parts of the automobile be suppressed to an
absolute
minimum.
Much
useful
information
on
ve-
hicular
noise
suppression
is
contained
in
MOBILE
MANUAL
FOR
RADIO
AMATEURS,
published
by
ARRL,
and
RADIO
AMATEUR’S
MOBILE
HAND-
BOOK, published by CQ magazine.