Path: utzoo!mnetor!uunet!husc6!cmcl2!nrl-cmf!ames!pasteur!ucbvax!ALASKA.BITNET!FNRJH
From: FNRJH@ALASKA.BITNET
Newsgroups: comp.sys.zenith.z100
Subject: RE: MEMORY UPGRADE
Message-ID: <8801230207.AA16233@ucbvax.Berkeley.EDU>
Date: 22 Jan 88 18:31:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 25


From: Robert Jesse Hale III


Dave  I put the FBE mod in my old H100 and it worked.

The only problem I ever had with the upgrade was for a while I would
get a random buss error.   I traced the error to the grid that jumps
pin 1 on all of the memory chip sockets.   What was happening to my
machine was the chip would heat up and move ever to small of a length
and blam, it would cause a buss parity error.   My solution was to go
back  in and move the pin 1 on the memory chip so that it sanwiched the
jumper in the socket.

      ---------- --------
      | jumper | |       | ... ect
      | pin 1  | | pin 2 |
      ---------- ---------
     ^
     |____part of the chip socket.   pin 1 presses aginst jumper to
          maintain a firm hold.

Since that mod I have never had any problems.   No dowm time.  I have a
feeling it was just one loose conection.    Put my mod in last september.
Good luck.   Robert