Tektronics 2235 Oscilloscope

[Gerd]

I have a Tek2235 oscilloscope that does not power up. Pilot light does
not come on. AC voltage OK, no burn signs inside. Any trouble shooting
suggestions?

 

[Kevin Carney]

Replace the electrolytics in the power supply, maybe that will fix it.

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[Jim Yanik]

Replace the electrolytics in the power supply, maybe that will fix it.

I'd check for a blown fuse first.Hear any noises,like a clicking or
chirping?

This scope has a pre-regulator that takes rectified line V and drops it to
~43VDC,then uses that in a power oscillator to generate the secondary
voltages. The Pre-reg FET may have failed,or one or both of the switching
xstrs and/or the 1 ohm fusible resistor in the inverter.Shorted rectifier
diodes were common,too.Then check electrolytic cap ESR for all the
secondary PS filter caps.

 

[Hugh Prescott]

Join the TEKScope group on Yahoo

Your scope model is discussed frequently.

IIRC major problem is failure of custom no longer made or available IC's.

Hugh

 

[Jim Yanik]

Join the TEKScope group on Yahoo

Your scope model is discussed frequently.

IIRC major problem is failure of custom no longer made or available IC's.

Hugh

Not in a 2235.