I love watching these vids while diaging. I beat you to the problem (15uf 20v tant on osc board) but man it feels good to have a fix and get a great piece of gear working!
Excellent troubleshooting and repair! Tantalum capacitors can be a real pain, the signal generator I am currently repairing had 20 volt rated tants on a 20 volt rail - something I would never do. Tants don't like spikes and seem to fail shorted frequently. Regards, David.
Usually tantalum capacitor fail due to heat or the excessive ripple on power rail. I had a few fail on a rohde & schwarz smt-03 as well as a few HP 04 amplifiers and was due to ripple and pulled power supply and pretty much every capacitor was leaking at the bottom and could not see it as didn’t leak out of under capacitors yet. Most tested good ESR even. But definitely some were out of specs.
Yes, those capacitors commonly go bad... It think it is best i you change all of the ones that are simular, otherwise you will have more problems in the future.. (i know from experience)
Check for ripple and noise on the power supply outputs when the unit is running, if there is a lot of ripple on the supply it could blow some more tantalums as they really don't like too much ripple, especially when they are not sufficiently voltage rated, a 20V cap on a 15V rail is way too close for a Tant.
Master Level diagnostic! That self test pass was a relief.
I love watching these vids while diaging. I beat you to the problem (15uf 20v tant on osc board) but man it feels good to have a fix and get a great piece of gear working!
Well done. Those yellow tans ate notorious for failing short circuit. Watched all the way through. Thanks.
Nice job on this generator! Subscribed.
Many thanks!
Your stuff is very informative too, Ray.😁
Excellent troubleshooting and repair! Tantalum capacitors can be a real pain, the signal generator I am currently repairing had 20 volt rated tants on a 20 volt rail - something I would never do. Tants don't like spikes and seem to fail shorted frequently. Regards, David.
@24:00 Yes those are tantalum caps, I have seen those fail a lot in a Tektronix 2432A scope.
Yep they are problematic for sure Scott!
Usually tantalum capacitor fail due to heat or the excessive ripple on power rail. I had a few fail on a rohde & schwarz smt-03 as well as a few HP 04 amplifiers and was due to ripple and pulled power supply and pretty much every capacitor was leaking at the bottom and could not see it as didn’t leak out of under capacitors yet. Most tested good ESR even. But definitely some were out of specs.
More good progress.
Yes, those capacitors commonly go bad... It think it is best i you change all of the ones that are simular, otherwise you will have more problems in the future.. (i know from experience)
Check for ripple and noise on the power supply outputs when the unit is running, if there is a lot of ripple on the supply it could blow some more tantalums as they really don't like too much ripple, especially when they are not sufficiently voltage rated, a 20V cap on a 15V rail is way too close for a Tant.
Yes, I will. Thanks