Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!hplabs!hp-ses!hpcea!twakeman
From: twakeman@hpcea.CE.HP.COM (Teriann Wakeman)
Newsgroups: comp.sys.mac
Subject: Re: How to mount SIMMS in Mac+ ?
Message-ID: <430086@hpcea.CE.HP.COM>
Date: 1 Mar 89 18:51:19 GMT
References: <934@swisun.swivax.UUCP>
Organization: HP Corporate Engineering - Palo Alto, CA
Lines: 32

RE: Going back to 1 Meg.

If you, like me are thinking of taking your RAM with you to your next 
Mac platform, whatever or whenever it is, only clip one end of the 150 ohm
resistor, lift the free end off the board, & if you want, put a wrap of
electrical tape around the resistor covering the free end. Pack your old
256K SIMMs into the anti static packaging that your 1 meg SIMMs came from
& pack them away.

When & if it ever comes time to pull up 1meg SIMMs and move on, just repeat

the installation process, resoldering the lifted lead {use a low wattage
solder iron with grounded tip}.

About this resistor- it is 150 ohms, R8 on a +, located at board
coordinates C1 {far away from the SIMMs on a +. There is a white rectangle
printed on the board areound R8 and R9 locations.

On an SE,the 150 ohm resistor to be cut is R35, which also lives in a small
white printed rectangle labeled "RAM SIZE". There is a label near the
resistor that says 256K but this referes to SIMMs & not the resistance of the
resistor. The resistor is a small brown cylinder with leads coming out each    
end and colour bands. The colour bands tells the resistance and tolerence of
the resistor {tolerance band optional, %20 iff missing}. The bands are read from
the band closest to the edge. R8,on a +, R35 on a SE, is brown{1},green{5},
brown{0}, gold {5% tolerence}.  If you cut if competely off, you can
replace it at any electronics store.

CAUTION: Solder suckers are sources of high static charges and may destroy 
CMOS circuitry.

TeriAnn