Radio Shack TRS-80 User Manual page 206

a
PRINT
9
REM *
CHECKSUM PROGRAM
*
10
IN. "
THE FIRST DIGIT
IS
"
t
A
30
IN."
THE SECOND DIGIT 15
"
iB
50
IN. "
THE
THIRD DIGIT
IS
" iC
70
IN." THE
FOURTH DIGIT
IS
"
)D
90
IN. " THE FIFTH DIGIT
IS
"
;E
110
IN."
THE
SIXTH DIGIT
IS
"
;F
160 P.
170
P." THE NUMBER IS
"
i
A
i
B
;
C
t
D
t
E
i
F
,
180 S = A +
2*B
+ C
+
2*D
+
E
+
2*F
210 T = INTI
S/10>
220 U
= S - T*
10
230 S = T + U
240 IF S>9
G.210
290
P." THE CHECKDIGIT
IS
"
;
S
Figure
1
Design
Program For
Cubical
Quad Antenna
The
cubical
quad
is
an exceptionally fine
antenna for use
in
receiving
and trans-
mitting
ham,
citizens
band, short
wave
broadcasting, industrial,
public
service radio
and television signals. It
is
rotatable,
being well-balanced and lightweight,
even
when
not raised very far off the
ground.
Electrically,
it
consists
of
two
loops of wire,
one of which
is
fed
with coaxial cable
or twin
lead,
the other simply soldered together
at
its
ends. Figure
1
is
an
illustra-
tion
of
a
quad.
The program inputs only
your desired operating
frequency.
It
then calculates
and
outputs
all
the
mechanical dimensions needed so
you can construct
your
own
quad.
Happy
designing!
s
CLS
B
P." CUSTOM
DESIGNING YOUR OWN
HIGH GAIN ANTENNA
>>—>>"
9 P.
IS
IN." CENTER FREQUENCY
(IN
MEGAHERTZ)
=
" |F
20
CLS
25
P. " >
>
CUBICAL QUAD
ANTENNA
<
<"
30 P.
40
E=.985
* F
50 G=1.033 * F
60
D=1000/F
100
R=1032/F
140
B=lie/F
180
X=(2*{R*R/64)
)
190
GOSUB 10000
195 S=Y
200 X=(S*S +
<B*B/4))
210
GOSUB 10000
215 P=Y
220
X
=
(<R*R/64) + 75 *
75/(F*F*41)
230
GOSUB 10900
2
35 T=Y
240
X
= <<R*R/64>
+
125*125/(F*F*4)
}
242 GOSUB 10000
245 U=Y
260 W=468/F
520
P."
THE
DESIGN CENTER FREQUENCY IS" |Fi"
MHZ.
204