[Boatanchors] Multi-Layer PC Board Component Replacement

[WA5CAB at cs.com]

Pace and Automated Production Equipment (APE) are American companies that 
make equivalent repair soldering-desoldering equipment.  APE second sources Pace 
consumables (mostly tips and filters).  Their equipment often shows up on 
eBay.  I bought a Pace PPS-5 dual soldering-desoldering station off eBay for about 
$100.  Don't know how I lived without it.  There is nothing technically wrong 
with the Hakko gear.  But the Pace and APE stuff is just as good, especially 
the earlier models without the unnecessary microcontroller nonsense).  And are 
US made.  

Anyway, back to the original post.  I would remove the defective chip, 
regardless if what brand desoldering equipement you use, and install a socket.  But 
if the chip is known to be bad and you don't have the high-end equipment that 
will remove an entire mega-pin chip in one operation, I would modify the 
procedure to first clipping all the legs on the component side and removing the 
chip body and discarding it.  Then I would remove the pins one at a time.  Far 
less chance of board damage this way.  But you destroy the old chip before you 
begin.  

Of course you can also buy gear that will remove the entire chip in one swell 
foop.

With proper desoldering gear, either single pin or complete package, there is 
less chance of damaging the board n my opinion than there is in attempting to 
piggy-back a socket onto the old chip pins.  And no chance of creating a 
short.  Remember that as the solder around each clipped off pin is melted, the pin 
is free to move around.  And there is no way in which you can control it as 
it is going to be up under the socket pins and inaccessable.

Anyway, aside from the above political comments, I agree with Jim.  Remove 
the chip.

In a message dated 1/20/2009 7:26:00 PM Central Standard Time, 
jimlarsen2002 at alaska.net writes: 
> This is just an observation.
> 
> Recently, a local ham operator had to replace the mega-chip in his Yaesu 
> FT-736R.  He borrowed a friend's Hakko 808 desoldering tool.  He moved 
> from pin to pin with the 808 and when he got to the last pin, the chip 
> just dropped out onto the table.  It was a simple job then to solder in 
> the new chip.
> 
> References:
> http://www.kiesub.com/hakko808.htm
> http://www.n0ss.net/hakko_808_notes.pdf
> http://www.tequipment.net/Hakko808.html
> http://www.hakko.com/english/maintenance/jyokyo_index.html
> 
> The Hakko 808 is not cheap but then the results seem to be outstanding.
> 
> 73, Jim
> 
> Jim Larsen
> http://www.AL7FS.us/   
> Anchorage Alaska    (907)345-3190
> 
> 
> 
> Richard W. Solomon wrote:
> >I have a Spectrum Analyzer that needs a memory chip replaced. Later
> >versions of this unit have sockets, mine has them soldered in.
> 

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480
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