Have any volt-nuts refurbished a Fluke 540B and replaced the 1.35V Mercury cell? I saw someone in Germany that used five AA NiMH cells in parallel to achieve better stability than just one call. Has anyone invented the wheel already and looked into the Fluke solution (2 AA with a 3 terminal regulator) vs 1. 5 NiMH in parallel 2. 1 NiMH cell only 3. Some NiMH calls with a stable reference device, rather than a regulator. Thanks, Victor

All of mine have a modification Fluke provided that replaces the mercury D cell with two AA sized alkaline cells and a small circuit board that has an adjustible LM317 3 terminal regulator set to make 1.35V. There is no need for the 1.35V to be all that stable, as it is just a short term reference used with the galvanometer to transfer a DC value that provides the same thermocouple response as the AC value being measured. It is not like mercury cells were all that stable in the first place, and the LM317 is much better. -Chuck Harris Victor Silva via volt-nuts wrote: > Have any volt-nuts refurbished a Fluke 540B and replaced the 1.35V Mercury > cell? > > > > I saw someone in Germany that used five AA NiMH cells in parallel to achieve > better stability than just one call. > > Has anyone invented the wheel already and looked into the Fluke solution (2 > AA with a 3 terminal regulator) vs > > 1. 5 NiMH in parallel > 2. 1 NiMH cell only > 3. Some NiMH calls with a stable reference device, rather than a > regulator. > > > > Thanks, > > Victor > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/listinfo/volt-nuts_lists.febo.com > and follow the instructions there. >