Amateur Radio Report Card

Fig. 4-Final Sub-Chassis : Screen resi.stor
is shown at upper left. Coupling capacitor,
.001 mfd mentioned in text, is shown at
lower right.
When you connect the .001 mfd capacitor
to the 5763 Multiplier plate, leave the other
end hanging with a one inch lead. This will
later be connected to the variable capacitor
on the Final Chassis.
F INAL SUB -C IIASS IS- ~ [oun t a 2-terminal
plus ground tie lug as shown in the photo.
The 22K ohm grid resistor will con nect to one
terminal along with a 15 inch length of wire
which will later be con nected to the Grid
Meter on the front panel. Connect the filament
wire to the other terminal. Also mount
a I-terminal tie lug, as shown, to which you
w iII connect the screen resistor, and later on,
the modulation transformer and Plate Meter
wire.
MODULATOR SUB-CHASSIS -
Connect
the microphone jack to the 6ANS socket on
this chassis with a short length of wire. The
jack will be mounted on the back panel at the
same time the Modulator Sub-Chassis is
mounted. The Gain Con trol on the back panel
is connected to the Modulator Sub-Chass is by
two 3 inch lengtbs of shielded wire. Do not
cut the primary leads of tbe modulation
transformer, but connect them fuII length to
the 6CZ5 tubes. T his transformer also will be
mounted the same time as the Modulator Sub­
Chassis.
Mounting
After wiring the sub-chassis, take the main
chassis-cabinet. Mount on the front panel,
from left to right as shown: Grid Meter;
leave next hole open for crystal switch; panel
bearing to which will be connected the variable
capacitor mounted on the Final Sub­
Chassis by a 3 inch flexible shaft; 15 mmfd
variable capacitor; 100 mmfd variable capacitor;
Plate Meter. On the back panel mount
the Gain Control, Power Plug, and antenna
coax connector as shown .
Mount the Exciter Sub-Chassis on the left
as shown, mounting at the same time the crystal
socket and crystal switch. Now back to the
ground connections we were talking about.
Using 3 separate wires or a 3-conduct.or cable,
connect the 2-terminal plus ground tie lug to
the B+ , A+ , and ground terminals on the
Power Input Plug.
Mount the Final Sub.Chassis in the center
rear as shown. Connect the .001 mfd capacitor
from the Exciter Sub-Chassis to the variable
capacitor on the Final Sub-Chassis. Connect
the A+ filament terminal on the tie lug to
the A+ lug on the Power Input Plug. Connect
the ground terminal on the tie lug to the
ground lug on the Power Plug. Connect the
15 inch lead to the Grid Meter. Ground the
other terminal on the Grid Meter. The B+
will be connected later.
Attach a 3 inch flexible shaft from the
variable capacitor on the Final Sub-Chassis
to the panel bearing on the front panel. Connect
a plate cap, output coupling capacitor,
output coil, and 52 ohm coax to the front
panel variable capacitors, antenna connector.
and rf choke. The photo of the top view will
aid you here, using the schematic for exact
connections. The rf choke connects from the
plate cap to the Plate Meter. The other meter
terminal connects to the I-terminal tie lug on
the Final Sub-Chassis through a shielded lead
Mount the
Modulator Sub-Chassis on the
right. At the same time mount the microphone
jack and modulation transformer. Connect the
2 shielded leads to the Gain Cou trol. Select
the wires on the secondary of the modulatior
transformer corresponding to 5000 ohms, ani
connect one to the I-terminal tie lug on the
Final Sub-Chassis. Connect the other to the
B+ terminal on the Power Input Plug. De
not solder the lead to the I-terminal tie IUE
until after the testing section.
Special Filament Consideration
If fixed operation is intended WIth a 6 vof
filament supply, wire the filaments as shown
If mobile operation is considered with a H
Fig . 5- Modulator Sub-Chassis: The two
6CZS sockets are at the left. The choke
in the photo was wi red in the filament lead
of the 6AN8. It was later found not to be
necessary, but was left in.