[volt-nuts] Solartron 7081 With Bad WR057 Diode

[Charles Black]

It's D110  on PCB6. After removing D110 the 7081 read about +2.5 
microvolt with the input shorted with an  external jumper. When I 
shorted the HI amp input with the MYTCHETT test point the 7081 read 
about -1.0 microvolt with low noise. I expect that the D101 (DPAD1) is 
the culprit.

Presently: Compared to my ancient HP3458a (last calibrated in 1990 and 
still on CAL 1) the 7081 reads about 10 microvolts higher. The 7081 
reads about 25 microvolts higher than my not quite as ancient Ag3458a.  
The Datron 4910 was calibrated by Fluke in March of 2012.

I'm going to change out temperature sensitive parts and leaky parts and 
remeasure.

Charlie


At 10V input the 7081 reads about
On 10/31/2014 12:30 PM, John May wrote:
> As a matter of interest which particular diode is causing these symptoms?
>
> On 31 October 2014 15:18, Todd Micallef <tmicallef at gmail.com> wrote:
>> Charlie,
>>
>> Calogic appears to sell directly, they may even send you a sample. I guess
>> it wouldn't hurt to ask.
>>
>> Todd
>> _______________________________________________
>> volt-nuts mailing list -- volt-nuts at febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
>> and follow the instructions there.
> _______________________________________________
> volt-nuts mailing list -- volt-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> and follow the instructions there.
>
>
>