More work on the Tek 475A. Decided to risk the balance of the tantalum change out. Most of the remaining are 1uf and 2.2uf. I have good stock of them so if they start giving trouble I'll change them out.
Checked the 1KHz vertical compensation on both channels 5mV all the way up to 5V and it's excellent. No adjustments required. The last time this scope was calibrated was in 1994. But what I find with former IBM equipment is that it's typically in real good shape and not abused.
Here's a 20MHz square wave from the Heath IG-4244 Scope Calibrator.
WCH....if you want to do a minimum change out of the tantalums with some level of confidence that the scope will continue to give good service here is the list of the ones I changed. Considerably smaller than total number but I think it's worth the risk. (It's all 4.7uf and larger) :
C291
C570
C913
C967
C1317
C1318 – This is a must do.
C1428
C1448
C1458
C1468
C1478