BGW 150 - Terminating Resistance Calculation; Calculating Load Resistor

03051
TERMINATING RESISTANCE CHART
How to find
terminating resistance
for balanced or
unbalanced
600 ohm
lines, driving
more than
one amplifier.
STEP
A
Input Impedance
of
Amplifiers Total Load Impedance
Number
of Amplifiers
“
of Amplifiers
STEP B Total
Impedance
of Amplifiers
-
600 K (Impedance Factor)
STEP
C
™~60(5
“
(i+l)x
600 ohms
=
Load Resistor Required
EXAMPLE:
Input
Impedance
of Amplifiers
=
15,000
ohms
Number of Amplifiers
=
4
A
1M92.
-
3750
ohms
B 3750-600
e
Too
=
5
- 25
C
x 600
=
1.19 x
600 =
714.29 ohms
Closest
value
is 715
ohms 1%
metal
film resistor.
*
Note ail amplifiers must
have the
same
input impedance. If
not, use
formula
below:
30k and 7.5k
1
X
+
+
X
Zi
Zj
Z
u
EXAMPLE:
Total
Load Impedance
Four
(4)
Amplifiers with
input impedance
of
15k, 30k,
1
lfffc
50
K.
50(C
7.SK
=
3750 ohms