Miguel, please check more carefully the age of your instrument, and please indicate precisely what's printed on the SnapHat batteries! Agilent branded 3458A were made from about 2000 onwards only, and the newer A5 board even later, so your batteries can't be from 1999 or 1994. Please check in your unit, compared to here: https://xdevs.com/fix/hp3458a/#a5rev, what the date code on U110, or U111-U113 is. That's more probably the age of your unit, or of the A5 board, I strongly assume it's from 2004. The date code on the ST SnapHat batteries is decoded like '99 YMM'. If you have something like 4xx for this D.C., then it's probably 2004. This Guy M.J. Lorton in his video https://www.youtube.com/watch?v=loQYTtrFqKY completely confused the decoding of his freshly bought SnapHats. 741 were his original batteries, which probably decodes into 2007, CW41 He then bought new batteries in 2016 and these were all either 429, or 452. These batteries were all from 2014, not 2004, as he assumed, not thinking about a probable 10 years wrap around of the D.C. New batteries with 8xx or 9xx should be fine, being from 2018 or 2019. Frank

On Thu, 12 Dec 2019 at 10:02, Frank Stellmach <frank.stellmach@freenet.de> wrote: > Miguel, > > This Guy M.J. Lorton in his video > https://www.youtube.com/watch?v=loQYTtrFqKY completely confused the > decoding of his freshly bought SnapHats. 741 were his original > batteries, which probably decodes into 2007, CW41 He is a great character if one has insomnia.😀😀😀😀 I like his video where he measured the noise on a 3457A multimeter by looking at how much the last few digits varied when connected to a bench multimeter. The guy is a complete ***** Dave. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@kirkbymicrowave.co.uk https://www.kirkbymicrowave.co.uk/ Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom