Repairing an HP3421A (Signature Analysis)

In the HP Journal issue of May 1977 http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/hpjindex.html there is an article about signature analysis. Otherwise the service manual of the HP 5004 http://www.gamearchive.com/General/Data_Sheets/HP5004.pdf or 5006 should help you further. The signature check is related to the CRC check. -Rik > -----Oorspronkelijk bericht----- > Van: cctalk-bounces at classiccmp.org > [mailto:cctalk-bounces at classiccmp.org] Namens vp > Verzonden: donderdag 4 juni 2009 21:16 > Aan: cctalk at classiccmp.org > Onderwerp: Repairing an HP3421A (Signature Analysis) > > I am trying to repair an HP3421A data acquisition and control > unit that fails its power on tests. > > In the service manual it refers to a number of "Signature Analysis" > tests that essentially mean that the unit runs some > diagnostic routine and you go and collect "signatures" from > various test points. > > Unfortunately I do not have a device to compute these signatures. > > Does anybody know how to calculate them using a logic > analyzer (I have a Bitscope and an HP 1630D), or something similar? > > Thanks > > **vp > > >