[volt-nuts] 3458A - To Modify or Not To Modify?

[J. L. Trantham]

I really appreciate everyone's thoughts about this.  If I do it, I will
certainly use gold plated sockets.  I have some of those on the shelf.  I
don't believe they are 'machined' though. 

I'll look at the Mill-Max items and see if I can get a set ordered.  

My only hesitancy is that it is such a nice unit coupled with my desire to
keep equipment 'original' and the potential to damage the meter.  However,
if I get the sockets installed, harvest the data from the NVRAM's, program a
new set of NVRAM's, install those then off to HP for their $550 cal and it
all works, I think that would be my preference.  If it fails, then the
repair.

I have added sockets to a number of other boards in other HP equipment but
never anything quite as expensive as the 3458A.

Solder suckers and desolder braid have been my tools.  I'll have to also
look at the possibility of adding a 'vacuum' type desolder iron.  I have a
real cheapie that uses only a bulb that I have never been particularly fond
of but perhaps I could hook it up to an external vacuum then trigger the
vacuum at the appropriate time.

Joe

-----Original Message-----
From: volt-nuts-bounces at febo.com [mailto:volt-nuts-bounces at febo.com] On
Behalf Of shalimr9 at gmail.com
Sent: Sunday, November 06, 2011 10:22 AM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] 3458A - To Modify or Not To Modify?


I think the main issue with sockets is long term reliability. The 5370 is a
good example. Both units I have suffered from bad socket syndrome, even
though it took a crowbar to pull the chips out. Contact pressure was not
lacking, but corrosion set in anyway. After replacing the cheap (and old)
original sockets with new sockets with machined contacts, problems went
away. A painstaking job, but well worth it.

Didier KO4BB


Sent from my BlackBerry Wireless thingy while I do other things...

-----Original Message-----
From: "Bill Gold" <wpgold3637 at att.net>
Sender: volt-nuts-bounces at febo.com
Date: Sun, 6 Nov 2011 08:02:56 
To: <volt-nuts at febo.com>
Reply-To: Discussion of precise voltage measurement <volt-nuts at febo.com>
Subject: Re: [volt-nuts] 3458A - To Modify or Not To Modify?

Joe:

    After opening my meter and trying to get the NVRAM out of the sockets I
used I have changed my mind and IMHO there would be no way, in normal
shipping and handling, that these NVRAM would ever come out of their
sockets.  I cannot remove them with my fingers by just pulling upwards and I
almost can't get them out by rocking them back and forth in the sockets.  It
is easier to remove the ribbon cables than it is to get the NVRAM out of
these sockets.  If the meter took a G force shock sufficient to cause the
NVRAM to come out of their sockets, then the meter would probably be non
operational also and would require extensive repairs, once the NVRAM was put
back into the sockets after the shock.

    I can't identify the brand of "machined" sockets I used but they are
very similar to the "Mill-Max" brand in the Allied catalog.  Mine are simply
branded with a "S", with a bar on the top and bottom of the "S" but not
connected to the "S".

    I would have no problem shipping my 3458A to Loveland with these sockets
for the NVRAM, and even better if I used the shipping box provided by
Agilent.

Bill
_______________________________________________
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.