Hello together, I have seen in a Fluke application note a block schematic of the Fluke 7000 voltage standard. In the picture there are 2 DACs (10 ppm / 0.4ppm) for precise voltage adjustment. See figure 5 on page 3: http://fluke.informationstore.net/efulfillment.asp?publication=10777-eng Does anybody know if there are really DACs which are used or if its only the usual BCD coding switches and the resistor string? If there are really DACs: which type (voltage output or multiplying DACs) are actually used? Which integrated circuit? Has anyone a repair handbook with schematic or photos of the pcb? With best regards Andreas

I remember that they advertised no switches in the signal path but 8 bit DACs instead. Makes sense, good switches and precision resistors cost more. No service documents available from Fluke, but I am not sure if Datron published something. 2012/8/29, Andreas Jahn <Andreas_-_Jahn@t-online.de>: > Hello together, > > I have seen in a Fluke application note a block schematic of the Fluke 7000 > voltage standard. > In the picture there are 2 DACs (10 ppm / 0.4ppm) for precise voltage > adjustment. > See figure 5 on page 3: > > http://fluke.informationstore.net/efulfillment.asp?publication=10777-eng > > Does anybody know if there are really DACs which are used or if its > only the usual BCD coding switches and the resistor string? > > If there are really DACs: which type (voltage output or multiplying DACs) > are > actually used? Which integrated circuit? > Has anyone a repair handbook with schematic or photos of the pcb? > > With best regards > > Andreas > > _______________________________________________ > 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. >