Shure SR105 - 70-Volt Conversion: Added Circuitry

11 TOOLS
/I Description
SR105B AMPLIFIER
PARTS
Pliers, Diagonal,
or Wire Stripper
*'Four machine screws presently securing rear-panel 70-Volt Conversion Cover (53A1319) may be used.
CONVERSION
MATERIALS
I( Pliers, Long-nose
Qty.
2
2
4
4
-
-
-
required.
Description
Transformer, 70V
Output
(T3)
Switch, Slide, DPDT
64)
Terminal Strip, 3-
Screw-Terminal (TS2)
Filter Circuit
Board Assembly
(A21
lamp socket assemblies; two more are
Qty.
1
1
1
1
Two locknuts
11 Screwdriver
Description
Locknuts, 10-32*
Machine Screws,
Phillips Round
Head, 4-40
x 3/16"
Machine Screws,
Phillips Head,
6-32
x % "
Machine Screws,
Phillips Head,
6-32
x '1'4 "* *
Wire, Hookup,
16 Gauge AWG,
Stranded Copper,
Vinyl Insulation
Wire, Hookup, 20
Gauge AWG, Stranded
Copper, Vinyl
Insulation
Solder, Rosin-Core
Shure
Part No.
51 A244
55C131
56A204
90A2038
are presently securing
I I
Screwdriver, Phil-
lips Head
I I
Soldering Iron,
Low Wattage
Wrench, Open-End,
Adjustable
FIGURE 15. 70-VOLT CONVERSION: ADDED CIRCUITRY
16
T3
GRN RED
J4 -J7
WHT
WHT
I -
-
YEL
BLK
r
-
TS 2
0
COM CT 70V
0
28V GND
0
TS I
FROM FILTER CIRCUIT s4-
OFF
BOARD PIN
V
FROM MAIN CIRCUIT
YEL/BLK
BOARD PIN J
FROM FILTER CIRCUIT BLU 0
BOARD PIN T
0
70 V
d 0