RCA 400 User Manual

77104
"B"
Figure 4 — Winding "Junior" Speaker Cable on Reel
connecting either device. Assemble the cable and
plug and connect the cable to the microphone or
phonograph pickup. Insert the telephone plug in the
jack marked MIC. Set the ON-OFF switch on the
amplifier in the ON position. Adjust the TONE and
VOLUME controls to obtain the most pleasing tone
and suitable volume of sound. Remove the micro-
phone—phonograph plug from the MIC jack when
sound films are to be shown.
For suitable microphones, phonograph pick-ups,
cables and plugs consult your dealer. The following
types of shielded—two—conductor plugs, or any
plugs similar to them, may be used: Carter *PG-52,
Switchcraft *70 or Mallory *75N.
PROJECTION PRACTICE
Choice of Focal Length of Lens
The focal length of the lens supplied with the
RCA Model 400 "Senior" and "Junior" projectors
is 2 inches. This is a value which meets average
projection conditions. However, in some instances,
lenses of different focal lengths may be required.
For example, it may be required to project a picture
of given size from different distances, as shown in
figure 3. Table I below gives the relationship be-
tween picture size and projection distance for
lenses of six different focal lengths. Lenses may
be obtained from authorized RCA Audio—Visual
Equipment dealers and distributors.
TABLE I PROJECTION DATA
Projection
Dist tnce
Feet
10
15
2Q
25
30
35
40
50
60
70
80
90
100
1"
lens
3*8"
5'6"
7'4"
9'2"
1TO"
• •••
• • • •
• * • •
• •• •
iVi"
lens
->'9"
4'2"
5'6"
6'11"
S'4"
9'8"
ll'O"
....
....
Picture
2"
lens
no"
2'9"
3'8"
4*7"
5'6"
6'5"
7'4"
9'2"
iro"
Width
2W
lens
\'TA"
2'5"
3-2H"
4'0"
4MO"
5W
6'5"
8'0"
9'8"
11-3"
3"
lens
^•w
2'T'
2'9"
V5/i"
4'2"
4'10"
5'6"
6M1"
8'4"
9'8"
ll'O"
4"
lens
OM1"
T4&"
no"
2'3tt"
2'9"
3'2ft"
3'8"
4'7"
5'6"
6'5"
7*4"
8'3"
9'2"
NOTE: Picture height is % of picture width.

RCA 400 Specifications

General

Power Supply	9V Battery
Type	Multimeter
Display Type	LCD
Dimensions	138mm x 69mm x 31mm
Weight	Approx. 170g (including battery)