I just traded for a 510A AC reference. It puts out 10 VAC. This one is marked 1000 Hz. Being cautious with such an old piece of gear, I brought it up slowly on a variac, so as not to blow the filter caps. Still not having sent off anything for calibration, I attached a 5.5 digit DMM to the 510A and it reads 09.9945. The DMM hasn't been calibrated in many years and I'm sure that the 510A hasn't been calibrated in at least 10 or more years (most likely many more, considering where it came from). I'll probably send the HP 3478A off for calibration after I get paid next week. Being 6.5 digit and freshly calibrated, it will be interesting to see how it reads the 510A. Joe Gray W5JG

On 08/09/2013 10:40 PM, Joseph Gray wrote: <snip> > I'll probably send the HP 3478A off for calibration after I get paid next > week. Being 6.5 digit and freshly calibrated, it will be interesting to see > how it reads the 510A. The 3478A is a 5.5 digit instrument (resolution of one part in 300,000). You might consider getting a 6.5 digit instrument before investing in the calibration. The HP 3457A is an excellent DMM and can sometimes be found on EBay for around $150.00. The 3455A is also 6.5 digit, usually available for less than $100.00.

Oops. It was getting late and I guess my fingers typed the wrong digit :-). Yes, I was thinking about getting a better DMM. Joe Gray W5JG On Sat, Aug 10, 2013 at 10:06 AM, Bob Smither <smither@c-c-i.com> wrote: > On 08/09/2013 10:40 PM, Joseph Gray wrote: > > <snip> > > > I'll probably send the HP 3478A off for calibration after I get paid next > > week. Being 6.5 digit and freshly calibrated, it will be interesting to > see > > how it reads the 510A. > > The 3478A is a 5.5 digit instrument (resolution of one part in 300,000). > You > might consider getting a 6.5 digit instrument before investing in the > calibration. The HP 3457A is an excellent DMM and can sometimes be found > on > EBay for around $150.00. > > The 3455A is also 6.5 digit, usually available for less than $100.00. > > > > _______________________________________________ > 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. >