260s are still being made new. Bought one new 3 -1/2 years ago when I worked in the oil industry.  Got the "ugly" Safety Yellow one so it wouldn't disappear!  We had some standard test procedures that required a 260 for safety checks on downhole tools.  I think I paid in the $250 to $300 range for the one I bought.

Tom H
 

 

 

 

Nice HP Dave!

Is the Simpson 260 still being manufactured?
http://www.ebay.com/itm/381021560492



On Fri, Nov 13, 2015 at 3:22 PM, Dave McGuire via vcf-midatlantic <
vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:

> On 11/13/2015 12:20 PM, Systems Glitch via vcf-midatlantic wrote:
> > I prefer an analog meter for troubleshooting -- like you said, easier
> > to detect an "is it off" condition, especially with intermittent
> > circuits. And, the loading of the analog meter can be an advantage in
> > many situations. My Simpson 260 is always on the bench, and I keep
> > the Simpson 160 in my toolkit since it's just the tiny version of the
> > 260.
>
> Same here, and the 260 is the king of 'em all. I have an HP 3458A on
> my bench (google it) but I end up using the 260 more, especially during
> calibrations.
>
> Stuff like the 3458A and other ultra-precision digital meters are
> great for measurement, while analog meters are much better for
> *adjustments*...a distinctly different application, while both involve
> measuring voltage. (or current, resistance..) The difference of course
> being that it takes less real-time brain processing to see whether a
> meter needle swings left or right than to read a displayed number,
> interpret it, decide if it's higher or lower than the last displayed
> number, ad infinitum. Doing that in real-time while tweaking an
> adjustment is a lot less efficient.
>
> > I opened it up this afternoon, it looks like the shunt for the 100 mA
> > scale is wire (nichrome?) wrapped on a phenolic bobbin, typical of
> > old small-value precision resistors. It's sleeved in some sort of
> > plastic tube which appears to have been clear originally, but is now
> > green over the section of wire. I'm guessing you're right and
> > corrosion has thrown the value off.
>
> The resistance wire alloy would be manganin (copper/manganese/nickel).
> Nichrome is rarely if ever used for actual resistors due to its very
> high temperature coefficient. Manganin's is negligible.
>
> You should be able to replace that with a modern resistor without
> trouble and get the ol' girl back up and running. Those DMMs are far
> from elegant, but they work very well.
>
> -Dave
>
> --
> Dave McGuire, AK4HZ
> New Kensington, PA
>