[volt-nuts] Dekavider DV411 repair and question

[Dave M]

> To everybode who answered: Thanks, so it was not only me not finding
> the leftovers of delimiters. Still curious why they made it that way.
> No reason to replace!
>
> Dave: I am aware of the resistor wire alloys like Konstantan,
> Manganin, Isabellin, Evanohm and their variants. What I didnt
> understand yet is the wiring between the resistors and the decades
> and so on - its just not simple silver-coated or tinned cooper wire,
> it more looks like a resistive wire - big and massive, bad to solder.
>
> Bill: Do I understand right, they use the inter-resistor wiring to for
> compensation ? (Your mail worked fine)
>
> Sounds like a "bigger but reproducable resistance than wildly drifting
> cooper wire" scheme to me. I try to figure out.
>
> The repair itself worked out very nice, the workplace 34401A in
> dcv:dcv ratio mode was happy with the results.
>
> BR
>
> Hendrik

Hendrik,
I didn't catch that you were asking about the interconnecting wiring.  That 
is likely to be the same material as used to make the resistors (Manganin). 
That would maintain the low tempco of the total unit, and avoid the 
comparatively large resistance drifts of copper wire.  Manganin is hard to 
solder without a flux that can remove the surface oxide that forms on 
manganin wire.  Flux used for soldering stainless steel might be a good one 
to try.  Just be sure to clean the joints very well after using it.

The old ESI standards are very nice instruments to have.  I have an old ESI 
decade capacitance box built like the Dekavider and Dekapot units.  It's 
quite accurate; good enough to allow me to evaluate RCL-type multimeters.

Cheers,
Dave M