R
Robert Obermayer
Guest
Hi,
i need some quick help with repairing a Tek TAS250 analog scope.
The deflection amplifiers were burned out due to a incident during
calibration (probe ground slipped) and as a result, 2 resistors were
burned beyond all recognition, as well as several transistors shorted.
I was sucessfull in finding the faulty transistors (i hope i found all
of them) and locating replacements (a little hard for the 2SA1206), now
the resistors are left.
I couldnt locate an affordable service manual that contains shematics
(Tek has a calibration manual but with no schematics or part lists).
Anyone either has the scope or the service manual and could help me here?
Resistors i need are: R331 and R340
Both located near a small heatshink on the board below the CRT.
Parts marked in this pic:
http://img266.imageshack.us/img266/6812/dscf0022es0.jpg
The scope is similar to the TAS220 (20Mhz) but the deflelction
amplifiers surely are not identical (also they use very different supply
voltage, 185v for the 220 and 145v for the 250, selected by a wire
jumper in the power supply) but the service manual likely lists part
values for both devices, as the PCBs are identical.
Regards, Robert
i need some quick help with repairing a Tek TAS250 analog scope.
The deflection amplifiers were burned out due to a incident during
calibration (probe ground slipped) and as a result, 2 resistors were
burned beyond all recognition, as well as several transistors shorted.
I was sucessfull in finding the faulty transistors (i hope i found all
of them) and locating replacements (a little hard for the 2SA1206), now
the resistors are left.
I couldnt locate an affordable service manual that contains shematics
(Tek has a calibration manual but with no schematics or part lists).
Anyone either has the scope or the service manual and could help me here?
Resistors i need are: R331 and R340
Both located near a small heatshink on the board below the CRT.
Parts marked in this pic:
http://img266.imageshack.us/img266/6812/dscf0022es0.jpg
The scope is similar to the TAS220 (20Mhz) but the deflelction
amplifiers surely are not identical (also they use very different supply
voltage, 185v for the 220 and 145v for the 250, selected by a wire
jumper in the power supply) but the service manual likely lists part
values for both devices, as the PCBs are identical.
Regards, Robert