Gonset G-66 - Installation; Mounting; Antenna Connections; Speaker Connections

INSTALLATION
MOUNTING
Brackets and other hacdware are furnished for
mounting the receiver under che dashboard of an
average automobile. Other mounting arrangements
are, of course, possible. Assuming that the No. 3069
or 3098 power supply is used, the simplest installa-
tion is afforded when it is attached directly to the
rear of the receiver case. This method is recom-
mended when space permits. Otherwise, the power
supply may be attached to the automobile firewall
with the maunting hardware furnished and connec-
tion made to the receiver with the 4-ft. patch cord
supplied,
Mounting details for a typical installation are
given in the accompanying drawing. Some receivers
are supplied with a dashboard mounting bracket of
slightly different construction but installation using
this type bracket is quite similar co that shown in the
drawing. Since the point at which the mountin
bracket attaches to the receiver will vary with dif-
ferent automobiles, no holes are provided in the
receiver case for bracket attachment. These holes
”) muse be drilled in the case and the bracket
fastened with the binder-head screws furnished. The
screws are to be inserted with the heads inside the
case to provide adequate clearance for the receiver
chassis. The chassis is then slipped into the case and
secured with the three bottom bolts.
When a slotted dashboard-mounting bracket is
supplied, fasten the binder-head screws to the case
with the nuts provided and then secure the case to
the bracket with the supplied wing nuts. This type
bracket permits slightly easier removal of the receiver
for servicing.
ANTENNA CONNECTIONS
Best
performance
is
obtained
when
a
whip
antenna
resonated
to
the
band
in operation
is used.
The
an-
ténna
connects
through
RG-58/U
coaxial
cable
to the
dower
antenna
receptacle
located
at che
left
rear
of
the
receiver,
When
operation
on
all
bands
is desired
using
a standard
8-ft.
whip
without
a loading
coil,
the
best
compromise
impedance
match
for
all
the
various
bands
is obtained
by
using
a connecting-cable
length
of
22
ft.
If
a transmiter
is installed
in
the
‘automobile,
the
antenna
connection
will
be
made
through
the
customary
T/R
relay.
Best broadcast-band operation requires the use of
a separate BC antenna which may be a standard side-
cowl whip. This connects through the normal coax
cable to the receptacle just above the high-frequency
antenna connector. ‘The two receptacles are coupled
by an adjustable capacitor which is accessible through
a hole located midway between the two antenna
inputs. When a separate BC antenna is used, the
capacitor is adjusted for minimum capacity (4 ta 5
turns counterclockwise from tight position) which
effectively removes it from the circuit. If desired, the
receiver may be operated on the broadcast band using
the
high-frequency
antenna
alone.
In
this
case
the
capacitor
is
adjusted
for
optimum
BC-band
perform.
ance.
This
type
of
uperation
has
the
disadvantage
that
changes
in
the
high-frequency
antenna
loading
coil
will
affect
broadcast-band
performance.
SPEAKER CONNECTIONS
A
speaker
is
provided
as
part
of
the
No.
3069
power
supply
and
connections
at
the
rear
of
this
power
supply
provide
for
the
use
of
this
speaker
or
an
external
speaker
as
desired.
Removing
the
steap
between
terminals
4
and
5
of
the
cerminal
strip
at
the
rear
of
the
power
supply
disconnects
the
internal
speaker.
The
external
speaker
is then
connected
to
terminals
3 and
4, If an
auto
radio
is already
installed
and
it
is
desired
to
use
the
auto-radio
speaker,
termi-
nals
3 and
4 may
be
connected
directly
to
the
voice
coil
of
this
speaker.
A
slight
loss
in
audio
power
output
and
frequency
response
from
both
receivers
will
usually
result,
however,
A better
arrangement
is
to connect
a switch
to transfer
the
voice
coil
to either
receiver
as required.
The No. 3098 poner supply contains no speaker
and, when using this type supply, a separate speaker
és required. Connect the speaker to terminals 4 and
5 of the power-supply terminal strip.
POWER CONNECTIONS
It is strongly recommended that the poverinpat
lead from the power supply be connected directly to
the “hot” terminal of the automobile battery, If it is
found necessary to extend the power-input lead, use
at least No. 14 stranded wire for 6-volt installations
and No, 18 wire for 12 volts. If these precautions are
not observed, frequency stability of the receiver on
the higher-frequency bands will be impaired due to
the wide fluctuation in heater voltage as the auto-
mobile generator operates. This instability is par-
ticularly noticeable on SSB and CW operation. If the
receiver is to be used only for a-m reception, the
power-input lead may he connected to the “accessory”
terminal under the dash of the automobile.
‘The No. 3069 power supply operates from either
an auto battery or from a 115-volt a-c source. Nec-
essary circuit switching is made automatically when
the appropriate cord 4s plugged in. In addition, the
power supply may be converted from 6 to 12-volt
operation by installing a vibrator of the correct volt-
age rating, installing a capacitor, modifying the
power-input plug and switching two connections on
the terminal strip located just to the reat of the
vibrator socket on the underside of the power-supply
chassis. These changes are detailed on the power-
supply schematic diagram.
The No. 3098 power supply operates only from a
12-volt d-c source and conversion to another voltage
source is not possible. A 6-volt model of this power
supply is available on special order.