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

Poul-Henning Kamp phk at phk.freebsd.dk
Sat Nov 5 06:27:33 UTC 2011


In message <000601cc9b4a$d9ba6b60$ebf25c47 at home>, "Bill Gold" writes:

>    Why HP didn't put the NVRAMS in sockets in the first place is beyond me!

That one is simple:  The NVRAMS have a rather higher center of gravity
than normal chips and tend to rattle out of their sockets.

The usual remedy is to 3mm holes on either side and a nylon strip around
the chip to hold it, just like you should always do with solder-in
batteries.

> The same with the ROMs.

The component cost of the CPU board is quite low, and there is nothing
on it which requires adjustment.

It is also the board which will often fail by ESD from the IEEE port.

It may easily be as cheap for HP to just plug in a new board, than
to fiddle with diagnosis and changing ROMs in sockets, once you account
for the technicians time.

So I suspect HP just didn't see the cost/benefit of sockets.

On the plus side, least my PCB was made so that unsoldering those
chips were particularly easy (bigger holes), so they clearly foresaw
the potential need to.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.



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