jalves_pt
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Hello all, I am needing help.
My Tektronix TDS 320 developed a bad symptom. After some time in the bench without use (nor connected to mains) I turn it on yesterday and find out that the TEK initiate the power on sequence and then start to do several clicks from the relays inside, but can't conclude the power on (sometimes it does, after a minute or two of clickings).
I open the oscilloscope and try to check the unit.
Measured the voltage output(s) of the power supply and when the Tek is working good, all the voltages are ok and in accordance with the values stated in the service manual.
The problem arises when during the clicking, during the delayed power up, the 5V rail maintain an oscillating value of about 2.9V, with the other voltages also on the low side and also oscillating.
I found that if I remove the ribbon that goes to the monitor board (nominal 15V) the Tek power up without problems except, off-course, the monitor is off.
Now my doubts, who is the culprit, the Power Supply board or the monitor board?
I am leaning towards the PS board, but since eventually the scope also works well (did an hour of endurance test, had to quit, the scope work well all the time after the initial clicking series till power on).
The service manual isn't of much help.
What do you think? What would you test in the scope?
My Tektronix TDS 320 developed a bad symptom. After some time in the bench without use (nor connected to mains) I turn it on yesterday and find out that the TEK initiate the power on sequence and then start to do several clicks from the relays inside, but can't conclude the power on (sometimes it does, after a minute or two of clickings).
I open the oscilloscope and try to check the unit.
Measured the voltage output(s) of the power supply and when the Tek is working good, all the voltages are ok and in accordance with the values stated in the service manual.
The problem arises when during the clicking, during the delayed power up, the 5V rail maintain an oscillating value of about 2.9V, with the other voltages also on the low side and also oscillating.
I found that if I remove the ribbon that goes to the monitor board (nominal 15V) the Tek power up without problems except, off-course, the monitor is off.
Now my doubts, who is the culprit, the Power Supply board or the monitor board?
I am leaning towards the PS board, but since eventually the scope also works well (did an hour of endurance test, had to quit, the scope work well all the time after the initial clicking series till power on).
The service manual isn't of much help.
What do you think? What would you test in the scope?
