开云体育

Hello I recently picked up a 453. When triggered on a sine wave it seems to flicker. Interestingly it will stop flickering when i reduce the time to a certain point. Wondering if someone can point me in the right direction. Attached is a video of the 453 flickering.

The sine wave is a sawtooth on the screen. The modulation is in the Z axis. These two make it sound like ripple in the power supply. I have worked on these and found most of the 1mfd axial tantalums as decoupling on the boards to be high in ESR. I replaced them with radial film types. In a few spots, I put in 22mfd tantalum to boost the decoupling. I had these in stock and used them. The main filter cans and decoupling from the regulators could be going bad. At the age of this, condensers going bad is likely. The cans are a pain to get out and reinstall. Restuffing is not hard, for me. Since the flicker stops at slower sweep speeds, dirty contacts are possible. Some resistors, mostly the carbon ones, are too small in wattage. It is possible some have gone high in resistance. Heather-cathode leakage in any of the Nuvistors?

Mark

So the flicker only shows up at slower sweep speeds it goes away as I slow the time base down.

That doesn't make sense? Show the display with the calibrator as input. Set trigger to Auto.