L
Lenny
Guest
This unit shuts down 2 seconds after power up. There is no output. I
found Q13, a Sanken 2SD2401 and Q17 also a Sanken 2SB1570, both
darlingtons shorted. The small transistor between them, Q1, a 2SC4137
is also shorted. CP1 the dual .22 ohm resistor has one section open
and R5 a small 10 ohm resistor shows signs of overheating and is open
as well. Mounted on the heatsink are two devices which plug into
sockets CN16 and CN17 on the main board. They look like thermal type
of devices and read open. One is marked Tokin 495 OHD3-75M and the
other is marked Tokin 695 OHD3-105M. Does anyone know what these are?
Has anyone worked on this model who might know if I need to check any
further or might I be reasonably sure that replacing these parts will
restore operation. There is a total of 3 pairs of 2SD2401 and 2SB1570
in this receiver. Might I have any kind of a bias problem mixing a new
pair of Q13 and Q17 with the other two pairs in the unit? Fimally does
anyone know of a source for the semiconductors? Thanks, Lenny Stein,
Barlen Electronics.
found Q13, a Sanken 2SD2401 and Q17 also a Sanken 2SB1570, both
darlingtons shorted. The small transistor between them, Q1, a 2SC4137
is also shorted. CP1 the dual .22 ohm resistor has one section open
and R5 a small 10 ohm resistor shows signs of overheating and is open
as well. Mounted on the heatsink are two devices which plug into
sockets CN16 and CN17 on the main board. They look like thermal type
of devices and read open. One is marked Tokin 495 OHD3-75M and the
other is marked Tokin 695 OHD3-105M. Does anyone know what these are?
Has anyone worked on this model who might know if I need to check any
further or might I be reasonably sure that replacing these parts will
restore operation. There is a total of 3 pairs of 2SD2401 and 2SB1570
in this receiver. Might I have any kind of a bias problem mixing a new
pair of Q13 and Q17 with the other two pairs in the unit? Fimally does
anyone know of a source for the semiconductors? Thanks, Lenny Stein,
Barlen Electronics.