Bill, I forgot to add, the Vishay bridge uses a Fluke 844 (OEM version of the 845AB) null-microvolt meter to read the bridge circuit. ESI did the same thing, first using a HP 419, and then a Keithly 155 OEM meter assembly, for their bridges.
The Fluke has its own supply from the line voltage. The batteries go to the DC current supply for the bridge itself. Thanks, Will *********** REPLY SEPARATOR *********** On 6/14/2011 at 6:13 PM WB6BNQ wrote: >Hi Will, > >You could consider building your own power supply system for the replacement of >the batteries. Use a separate power transformer which, I suspect, would be small >as the current requirements would be low for driving a bridge circuit. > >The main company to look toward for high quality, low noise regulators is Linear >Technology. Here is a candidate part to look at : >http://www.linear.com/product/LT3082 > >This is the lowest noise (33uv/10Hz to 100KHz) low dropout regulator that can >handle regulating 24 volts and is adjustable, meaning use can use this part for >all three voltages (i.e., three regulators). You will have to decide if it noise >specs are suitable for your needs. Keep in mind that battery noise is typically >random whereas the noise out of a regulated system tends to be constant. > >If you really think you need lower noise then you could consider an LT1000 shunt >reference. Typically the circuit designs for LT1000 type devices are as >references and lack current capability above about 10 milliamps. Adding >additional current circuitry would add more noise. See: > >http://www.linear.com/product/LTZ1000 > > >Bill....WB6BNQ > > >Will Matney wrote: > >> Hello, >> >> I am in need of a very clean 24 Vdc power source, to replace some old >> mercury cell batteries with. What would a good low noise, clean, power >> supply be in your recommendations? I thought of using two 12 Vdc lead-acid >> batteries in series, and making a charging circuit with regulators, but I >> am hoping to purchase a good used supply off ebay, etc. The old circuit >> used two 12 Vdc snap terminal mercury batteries in series, for 24 Vdc, >> along with a 7 Vdc mercury cell, and two plain AA carbon 1.5 Vdc batteries >> in series for 3 volts. Any help and or ideas would be appreciated. >> >> Thanks >> >> Will >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > >__________ Information from ESET Smart Security, version of virus signature database 5851 (20110206) __________ > >The message was checked by ESET Smart Security. > >http://www.eset.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
