Thank you, Mitch for the Rubicon data!!!!!
Willy
On 7/11/2014 7:32 AM, volt-nuts-request@febo.com wrote:
Send volt-nuts mailing list submissions to
volt-nuts@febo.com
To subscribe or unsubscribe via the World Wide Web, visit
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
or, via email, send a message with subject or body 'help' to
volt-nuts-request@febo.com
You can reach the person managing the list at
volt-nuts-owner@febo.com
When replying, please edit your Subject line so it is more specific
than "Re: Contents of volt-nuts digest..."
Today's Topics:
1. Re: AC Voltage Measurement Standards (Todd Micallef)
2. Fluke 5200A repair. (Kgoodhew)
3. Need info on L&N 4214 temp vs resistance plot.. (new)
4. Re: Need info on L&N 4214 temp vs resistance plot..
(Mitch Van Ochten)
Message: 1
Date: Thu, 10 Jul 2014 22:42:37 -0400
From: Todd Micallef tmicallef@gmail.com
To: Discussion of precise voltage measurement volt-nuts@febo.com
Subject: Re: [volt-nuts] AC Voltage Measurement Standards
Message-ID:
CALwLtXwYwdsD-y1tGXxSh+00jNTFEr+LiEfrfCTTuuLeGspM=Q@mail.gmail.com
Content-Type: text/plain; charset=UTF-8
The remark about calibrating the resistors was merely an example of how I
thought you may have been transferring the calibration of the 10V TVC. My
first thought was that you compared the 10V TVC to the next closest model
at fixed points. The inter-comparison would then continue from that model
to the next value down (or up).
I had a hard time trying to understand how that could be accurate, and the
thought of using a ratio transformer didn't cross my mind. Thanks for the
explanation.
I can see how the costs of calibrating a TVC can be so high. I am guessing
few labs possess the equipment to calibrate them and places like Ballantine
probably use NIST for their cals.
Todd
as far as your comment re. calibrating a set of resistor cal from one
calibrated one, whats wrong with it? if you do that with a stable voltage
and by voltage divider measurement using the linearity of the 3458A, you
end up with pretty decent accuracies. I cannot comment on the 242, just did
some quick checks some time ago and my quick assessment then was it is
worse/not better than the 3458a method.
Message: 2
Date: Fri, 11 Jul 2014 14:27:54 +1000
From: "Kgoodhew" kgoodhew@iinet.net.au
To: volt-nuts@febo.com
Subject: [volt-nuts] Fluke 5200A repair.
Message-ID: 004c01cf9cc0$7c9ea7a0$75dbf6e0$@iinet.net.au
Content-Type: text/plain; charset="us-ascii"
Hi Gerd,
C8 is on the drain of Q38 the Fet just near the input to the A7 amplifier,
according to Charles it is switched in parallel with C1 on the source of Q38
to vary the integration time.
Using the cro on dc to look at the output I get 15mv dc on the output and I
cannot vary it by R6.
Will do some further checking today.
Ken.
Message: 5
Date: Fri, 11 Jul 2014 12:38:05 +1000
From: Gerd admin@controlelectronics.com.au
To: Discussion of precise voltage measurement volt-nuts@febo.com
Subject: [volt-nuts] fluke 5200a repair
Message-ID: 53BF4E0D.9030808@controlelectronics.com.au
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hello Ken,
Which board are you looking at? On the amplifier board (A7) C24 is the
input cap. Where is C8?
Don't rely on the multimeter to filter out the AC on the DC ranges, it's
best to use a CRO. How is the signal coming into the amplifier from the
oscillator? If the input to the amplifier is disconnected, is the offset
still there?
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com
Message: 3
Date: Fri, 11 Jul 2014 00:35:34 -0400
From: new pitts7@williams-net.com
To: volt-nuts@febo.com
Subject: [volt-nuts] Need info on L&N 4214 temp vs resistance plot..
Message-ID: 53BF6996.9040906@williams-net.com
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I'm guessing that the 4214 10K standard has a resistance curve
that peaks around 73F??? I've searched for old pix of data and can't find
any. The 4214 I got this week had no old, original data with it in its box.
Over the past few years there have been some resistance standards
sold on fleabay with pictures of temp vs. resistor value charts pasted
on the top cover. They may not have been 4214s, though. I also just
discovered that fleabay drops its pix on items sold past a certain date.
So, volt-nuts.... any help??? Alphas, Betas, charts?
Willy
Message: 4
Date: Fri, 11 Jul 2014 07:25:59 -0400
From: "Mitch Van Ochten" mitch@vincentelectronics.com
To: "'Discussion of precise voltage measurement'" volt-nuts@febo.com
Subject: Re: [volt-nuts] Need info on L&N 4214 temp vs resistance
plot..
Message-ID: 00d401cf9cfa$e441fa80$acc5ef80$@vincentelectronics.com
Content-Type: text/plain; charset="us-ascii"
Hi Willy,
For what it's worth I have attached the resistance vs. temperature curve for
my 10 k Rubicon which is of similar construction. It has a peak at about
23.5 degrees C.
Best regards,
mitch
-----Original Message-----
From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On
Behalf Of new
Sent: Friday, July 11, 2014 12:36 AM
To: volt-nuts@febo.com
Subject: [volt-nuts] Need info on L&N 4214 temp vs resistance plot..
I'm guessing that the 4214 10K standard has a resistance curve that peaks
around 73F??? I've searched for old pix of data and can't find any. The 4214
I got this week had no old, original data with it in its box.
Over the past few years there have been some resistance standards sold on
fleabay with pictures of temp vs. resistor value charts pasted on the top
cover. They may not have been 4214s, though. I also just discovered that
fleabay drops its pix on items sold past a certain date.
So, volt-nuts.... any help??? Alphas, Betas, charts?
Willy
volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.