From: muratlanne@gmail.com   
      
    wrote in message   
   news:mj83ae9ethr168bk2g55vu0vov63h2ftlb@4ax.com...   
   > On Sun, 31 Mar 2019 08:53:48 -0400, "Jim Wilkins"   
   >  wrote:   
   >>.....   
   >   
   > I have that Drok (or its twin) and the 10 volt output is listed as   
   > 9.99668 volts.  I don't have anything that displays that many   
   > digits,   
   > but adjusting the calibration on an inexpensive (but stable and   
   > durable) DVM to 10.00 with that standard gives me readings of 0.005V   
   > or better.  The DVM was last checked in 2016 and when checked this   
   > week it was within 0.03V after almost 3 years.  That's very stable   
   > for   
   > my "Toss it in the toolbox" meter from Harbor Freight, but I've   
   > found   
   > that their very inexpensive DVM (in a red case) has an internal   
   > calibration pot and it holds calibration well.  I'm only interested   
   > in   
   > high accuracy in the range around 12 volts so calibrating the meter   
   > on   
   > the 20 volt range gives me acceptable accuracy over the range of   
   > interest.   
   >   
   > I have better meters, but it's nice to have some that can be left in   
   > convenient places and you know they'll probably survive a 5 foot   
   > drop   
   > to concrete and if the drop changes the calibration, you can correct   
   > that in a minute or two.  I also have one of these in each vehicle   
   > for   
   > troubleshooting vehicle problems or when I'm at someone else's house   
   > (I'm the family handyman and I always have some tools in my truck   
   > ;-)   
   >   
      
   The HF cheapies have an input impedance of 1 MegOhm and don't work   
   with high voltage range multipliers or to show the voltage of the   
   megger I use to hipot appliance repairs and measure diode and   
   lightning arrester breakdown. Otherwise they are great as battery   
   testing beaters that might be zapped by high current. I found the cal   
   pot touchy and sensitive to knocks.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)