[volt-nuts] Fluke 720A Kelvin Varley Divider Questions
randallgrayevans at yahoo.com
Mon Sep 20 14:18:58 UTC 2010
Does anyone know where and how to obtain the LK389 mentioned below. Linear
Systems has a high minimum order but i would like to pursue rebuilding my HP-419
since the chopper doesn't work (as usual).
----- Original Message ----
From: Bruce Griffiths <bruce.griffiths at xtra.co.nz>
To: Discussion of precise voltage measurement <volt-nuts at febo.com>
Sent: Sun, September 19, 2010 2:17:51 PM
Subject: Re: [volt-nuts] Fluke 720A Kelvin Varley Divider Questions
Charles P. Steinmetz wrote:
> Bill wrote:
>> You're kidding, right ?
> I've never used one, and I'd be interested to know what you (and others) think
>its failings are.
> Best regards,
A more general question would be:
Is it possible to design a chopper stabilised null detector using modern
components with a performance equivalent to the 845A?
Whilst the noise of most chopper stabilised opamps is much larger than that of
the 845A, perhaps something like the approach used in:
could be used.
Since the low noise preamp is AC coupled a lower noise input using a single
ended JFET could be substituted for the one using the LSK389.
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.
More information about the volt-nuts