Quote:
Originally Posted by TheAuger
I have 4 500 series scopes and never had probs with capacitors but if you do any soldering on the Ceramic strips/combs please be aware you should use Silver solder other wise you loose adhesion with the ceramic. The fault could be the E.H.T transformer some of these were prone to failure
|
On the first point, you need to use tin-lead solder with 2% silver. Definitely NOT lead free solder under any circumstances. The solder that Tek used was tin-lead with 3% silver, but 2% is easily available from Farnell/RS etc and is absolutely fine to use. Do not use just tin-lead, because the silver plating in the ceramic strip notches will dissolve in the solder and that will spoil your day.
Here's a Tek instructional video showing the technique for soldering onto the strips. The oscilloscope at the start is a 545 (not sure if it that or a 545a)
https://www.youtube.com/watch?v=RpB5JqGo1co (crossed post - Andy also posted this link)
And secondly the EHT transformers only fail in the much later 545B when Tek moved to epoxy potting. The original 545 and later 545A have EHT transformers which I have never heard to fail, and are wax potted.
Craig