I don't know what it would do to the rest of the components but I've found 5 minutes of exposure to a heat gun ( for paint stripping ) to loosen solder right up. Works great on multi pin through hole components.
On 9/17/03 6:04 PM, "Jeff Walther" <[EMAIL PROTECTED]> wrote: > At 14:53 -0400 09/17/2003, Compact Macs wrote: >> Date: Wed, 17 Sep 2003 07:23:07 +0100 >> Subject: Re: SE/30 Locks up at Finder start >> From: Stuart Bell <[EMAIL PROTECTED]> > >> >> On Wednesday, September 17, 2003, at 05:35 AM, Nolen Scaife wrote: >> >>> Sorry for the string of posts ;) >>> >>> After quite a bit of system folder copying and trial and error, I got >>> MacTest Pro to run. "SCSI Controller Failed!" is what it says. >> >> Makes sense! >> >>> Well, what are my options? I know I could just replace the logic >>> board, but are there any other methods? >>> >> I fear not. Changing the controller chip would be very difficult if not >> impossible unless you have surface-mount soldering equipment, and the >> only likely source of a chip would be a donor l/b in the first place. > > I think Zilog still sells the 53C80 chip. Digi-Key used to stock it > but no longer appears to. A google search turns up Mentor > Electronics, but their pricing is not on line, and guessing by their > web appearance, I bet they have a substantial minimum order, but I > could be mistaken. > > All moot, I suppose, because most folks aren't going to do that kind > of soldering at home. However, it is doable with soldering pencils > (I use a 15 watt and a 40 watt from RS) if you also have some Chip > Quik and a good bit of practice. > > Chip Quik is an alloy that one melts into the existing solder and it > lowers the melting point of the solder. By forming a bead of Chip > Quik around the four sides of a PLCC chip like the 53C80, it is > possible to heat all the pins on one side of the chip by applying a > soldering pencil to any point on the bead. > > Alternately heating all four sides on a small chip like the 53C80 > will eventually get it to come off the board without damaging the > chip or the board, because the melting temperature of the solder has > been lowered by the Chip Quik. For larger chips an adjustable heat > gun works well to heat all the pins on the chip simultaneously. > > One last bit of useless trivia. While a donor logic board would be > needed, it needn't be an SE/30 board. Most of the machines (all?) > in the Mac II family used the 53C80 as the SCSI controller. The > chip can be scavenged from a IIcx for example. The trick is getting > someone to supply you with one of these old boards rather than just > sending it to the crusher. The low value on these old machines > means that the cost in time to handle them is usually greater than > the selling price so a huge amount of them are going to disposal. > Sigh. > > Jeff Walther > -- Compact Macs is sponsored by <http://lowendmac.com/>. Support Low End Mac <http://lowendmac.com/lists/support.html> Compact Macs list info: <http://lowendmac.com/lists/compact.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/compact.macs%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
