Dust wise it's remarkably clean. I pulled out the CPU, A/D etc cards and there really clean and dust free. The previous owner seems to have taken good care of it, there's almost no dust around the cooling fan intake either. There are some electrolytic capacitors in the PSU section that are cable tied to the chassis that are looking a bit old. I could replace those with equivalent values and ratings and would be about a quarter of the size so I suppose that's a good place to start. Thanks everybody for you suggestions. -----Original Message----- From: Dave Tweed [mailto:pic@DTWEED.COM]=20 Sent: 01 March 2003 19:10 To: PICLIST@MITVMA.MIT.EDU Subject: Re: [OT]: Problem with Gould 4050 Storage Scope Joe Farr wrote: > I thought I'd try the list as I can't get a service manual for my Gould > 4050 Digital Storage Scope and it's developed an annoying fault. > > Once it's been switched on for a minute or so, the display starts to > shrink and then jump back to the correct size. At the same time, the > traces start moving up and down, left and right. During these 'fits', > the display brightness seems to fluctuate quite a lot as well. After a > while it seems to settle down with just the odd burst of trouble every > now and then. I'll be there's a bunch of dust inside that's slighty hygroscopic. Each time you turn it on, the high voltage finds some leakage paths until the accumulated moisture cooks off. Try opening it up and cleaning it out thoroughly (and carefully!), particularly around any high voltage sections. Use compressed air if you have it. -- Dave Tweed -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body