Re: tek 7904A...
You are headed in this direction, but I would suspect filter caps that have dropped in value. At light load, they would still work okay, but at heavier loads the ripple may get so large that regulators either drop out of regulation or otherwise pass the ripple along. I have had this same symptom with TM5xxx mainframes.
Having said that, I know nothing about the guts of a ‘7904 – whether the mainframe has rectifier / filter banks or not.
Good luck –
From: TekScopes@... [mailto:TekScopes@...] On Behalf Of Jim
Sent: Tuesday, December 22, 2009 5:09 AM
Subject: [TekScopes] Re: tek 7904A...
On Tuesday 22 December 2009 2:43:05 am d.seiter@... wrote: