This was in another thread. I thought I'd write down my progress on this for the sake of someone who may stumble across the same issue.
So I fired up my Tek 465B and nothing happened. So I bought another slightly less sick one to see what was up with it.
The issue manifested itself as no sweep. I found a broken resistor in the sweep generator after carefully probing around to see where the signal path stopped. It had cracked. This was replaced with a metal film one I had lying around. I didn't take any photos of that initially.
When this powered up I noticed there was a ton of ripple on the display and the triggering wasn't working properly. It would randomly trigger and occasionally just stop working all together. I noticed this was showing roughly the same behavior as the line trigger option so I poked around at the rails and discovered some ripple on the 55v rail. A quick inspection of the board and there was a blown Tantalum capacitor.
In circuit:
Extracted:
Exploded tantalum capacitor took the solder mask of the board. I cleaned it out carefully and replaced with a 4.7uF 100v alu electrolytic unit from RS. Total cost £1.87 for 5x. I had to use two as I crimped the leads slightly too short on the first one (doh). This was a case of desolder the first one, solder wick the holes out, solder in a new one without melting the RF cables in close proximity.
Result just on the calibrator (no sig gen in the kitchen
)
So now it's working reasonably well. The beam return blanking isn't working properly now (shows a light trace) and the intensity and focus is jippy but I'll sort that out in the next few days.
Then I'll fix the other one which has a noisy channel A and some ripple problems as well.
Edit: fix a duff link