Purchased an old Fluke 77 for sentimental reasons through the usual online 'place'. Listed as tested and working, ie showed a pic connected to a 9 volt battery
.
Anyway of course it did not function normaly when received so opening up showed some horrible gunk around the input jacks and some corrsion. A good IPA clean or two later and some deoxit on the input terminals and all was good again for the old timer.
BUT while it was appart I noticed some rather unusual component placement done at manufacture
. See the pics. for the best explanation.
Much comment is made about poor PCB assembly of products and even other upmarket DMMs in the past, and here is a pretty good example of one slipping through visual QC all those years ago.
AND has it mattered since then for this unit, not one bit and after the cleanup it was still in spec. no tweak needed and back in service.
note: 10V ref and 87V verified at work, so trust me the 77 was in spec.