LENCO R25 - Protection Circuit; Transistor Views; Dial Cord Stringing; Description of Exploded View

Protection Circuit
Current Limiter ‘L’
This circuit is designed as a protection circuit to protect the
speakers and power transistors from damage when the out-
put current increases due to an output short or overload.
if the current through R520 and R521 gives a voltage drop
across the resistors which is greater than the turn on voltage
of Q506 and Q508, then Q506 and Q508 are turned on and
the input to Q504 and Q509 is shunted.
Hence this circuit protects the power transistors and speakers
from damage by limiting the current.
Transistor Views
E
2SC 828
B
C
E
25C 1166
2SA 661
B
C
E
2SA 841 2SC 733
2SA 561 2SC 734
2SC 374 2SC 1681
28C 381
2SC 732
R-25 DIAL CORD STRINGING
DIAL PULLEY
2SC 789
Ys ti—“‘“ONCCCOUN
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C
ha
E
2SA 794
Description of Exploded View
. Handle
Knob
Knob
Knob
Knob
Knob
Knob
. Felt (lever switch)
. Bezel (push switch)
10. Bracket, phone jack
11. Bracket, power switch
12. Front frame
13. Power switch
14. Phone jack
15. Speaker switch
16. Pivot
17. Roller
18. Push switch
19. Roller
20. Scale
21. LED, LED holder
22. Meter (tuning, signal)
23. Dia! pointer
24. Acryl reflector
25. Bracket, lamp holder
OONDARONS
. Lamp, grommet
. Bracket, left side
. Cover, left side
. Cover upper
. Main frame
. Elect. cap. 4700 uF/35 wV
. Power transformer
. Heat sink
. P.C.B. pre-amp.
. Bracket, right side
. P.C.B. switch
. Tuning mechanism assy
. Front end
. Bottom cover
. Rubber foot
. Cover, right side
. AC socket
. Rear frame
. Socket protector
. Antenna terminal
. Speaker terminal
. AC cord with plug
. Voltage selector
. AM antenna assy
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