[volt-nuts] PPM LTD Model 410/411 Voltage Reference

Tony Greene tonygreen924 at inbox.com
Wed Aug 28 21:01:42 EDT 2013


Greetings.  I have lurked awhile and have finally found a reason to register and post.

I recently purchased a PPM Ltd. (England) model 410/411 voltage reference.  This unit is green colored and takes up one rack unit.  It appears to be zener based, it has a black box on the PCB that I beleive houses/sheilds the zener.  On the rear panel it has bananna jack that is labeled 6.25498V.  It has a 1KV and 100V input divider to 1 volt output.  It also has a switched output of 10V, 1V, 100mv, 10mv, 8mv, 6mv, 4mv, 2mv, 1mv, and zero volts.  The unit uses binding post for the inputs and outputs and it also has a sense and guard binding post.

The unit operates on 120 or 240 VAC and had 14 ea "C" nicad cells which were all corroded.  The batteries were configured so that 2 cells provided a negative supply, and 12 cells provided a positive supply.  The unit uses 0.005 percent wirewound resistors, they are green in color, but I do not reckonize who made the resistors.  The unit uses OP07 op amps, using the round "TO" style cans of old opamps.  The unit has a calibration sticker showing it was calibrated on 9-87, a transformer inside shows a made date of 1979.

I have not been able to locate any information on the net about the unit.  I would appreciate any information any person may have on the unit.

Thanks, Tony

____________________________________________________________
FREE 3D EARTH SCREENSAVER - Watch the Earth right on your desktop!
Check it out at http://www.inbox.com/earth




More information about the volt-nuts mailing list