The meter will be here in a few days. I did buy the ram. As far as the meter age goes, unless it is a very old hardware revision, I would rather have an old meter because it is more stable. That is until it brakes.
I do have before and after readings and the 4 readings are the only ones that failed. The after readings are better than the before readings. Because the 8 and 10 MHz failed we did not get a certificate but we do have a good limited calibration up to 2 MHz. Just no official cal. The cal we wanted was $1600. We will still have to pay that after the repair. >From what I can tell they did not run SCAL or the before/after readings would not have matched. Like they really did not run after readings or there would have been some mismatch. On Tue, Sep 17, 2013 at 6:50 PM, J. L. Trantham <jlt...@att.net> wrote: > John, > > Can you give us more information? Serial number, Rev. number, CALNUM? How > much to invest will be determined by age and other condition. > > It doesn't sound like a simple CALRAM issue but changing the CALRAM is > relatively easy. I removed all three DALLAS chips in mine and installed > sockets. The CALRAM can be read with a chip programmer and the data > written > to a new DALLAS chip. > > I would also call Gary Bierman at the Loveland Cal Lab and have a long talk > with him. He has a lot of insight into these meters and generally prefers > to do a component level repair rather than an assembly level repair. The > charge sounds like their standard repair charge, no matter what the problem > is, and includes a 'fresh calibration' along with a warranty, a year I > think, but Gary will be able to answer that question. > > Also, once you get the meter calibrated by Agilent (and thus prove it is > functioning normally) it will be eligible for their 'repair agreement' > which > is $178.68 per year. I would consider buying a 5 year agreement after the > repair. > > Good luck. > > Joe > > -----Original Message----- > From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On > Behalf Of John Phillips > Sent: Tuesday, September 17, 2013 3:36 PM > To: Discussion of precise voltage measurement > Subject: [volt-nuts] HP 3458A repair. > > Hi, > I have a 3458A that we sent to Agilent for calibration which it failed. > Before we sent it we calibrated it and it looked good to us. The infor. we > revived led us to believe that the cal memory may have caused the failure. > We ask that it be sent buck to us and paid half the cal charges (about > $800) insted of the $2660.64 they wanted to repair it. We were just going > to > repalce the ram in try again. > When we got the meter back it came with befor and afer data Like before 10 > volts read 9.9999957 and after it read 10.00009 so they did something or > the > meter drifted that much. > The problem is 0.1 volt and 1.0 volts failed at 8 and 10 MHz but passed at > 4 MHz. > 4MHZ 0.1 volt reads 0.097251 Lower Limit is 0.095930 PASSED 8MHZ 0.1 volt > reads 0.085712 Lower Limit is 0.0959 > 2 > 0 > FAILED > 10MHZ 0.1 volt reads 0.75569 Lower Limit is 0.084900 FAILED > > 4MHZ 1 volt reads 0.97272 Lower Limit is 0.95930 PASSED 8MHZ 1 volt reads > 0.86389 Lower Limit is 0.95920 FAILED 10MHZ 1 volt reads 0.73514 Lower > Limit > is 0.84900 FAILED > > The AC after readings are the same. I do not see how AC after could be that > identical even if they did not try to calibrate it. Did they just copy the > before data and call it after data? > > My best guess is that if the 4 MHz is in and the higher frequencies are not > the meter requires some kind of mechanical adjustment to get the frequency > response withing spec or the AC board needs to be repaid. > > Are they charging a standard repair charge to do a calibration? I do not > see > changing the memory to fix this. > > Where would you go from here if this was your meter? > > > -- > John Phillips > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > -- John Phillips _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
