phupp@warwick.ac.uk (S Millington) (01/08/90)
I've got a revision 6a UK A500. I've just done a DIY upgrade to 1meg chip
ram cos' GRANADA CBM's official service agents in the UK told me on the phone
that they couldn't get it to work after two attempts and have gone back to CBM
UK for help - how can changing two jumpers go wrong! Back to the subject -
I don't like soldering, read I can't solder to save my life, so I went to
TANDY, sorry for swearing, and bought a bottle of silver ink. For anyone doing
this job inside a 400pound computer who dosen't trust their soldering
skills this silver ink is a godsend, just paint it on where you would have
soldered, with a thin paint brush, and the jobs done. Far easier/safer than
sticking a massive soldering iron in next to fat agnus!
On the same sort of subject, when I rang CBM UK about the 1.5meg upgrade
for rev6a boards they claimed to be waiting for details from CBM US - because
of company policy not technical problems. Anyone from CBM US care to say when
CBM US will condesend to tell CBM UK about the upgrade?
As far as I can gather these are the rev 6a changes :
-- now uses 4 256kby4 chips for the initial 512k chip ram on the board
-- above chips use 4 of 8 sockets allowing 1meg on main board
-- 8372 FAT AGNUS already fitted - change 2 links with 1 meg for 1 meg
chip ram
-- can use either above sockets or A501[gives RTC - not on main board] for
1meg
-- CAN use both for 1.5meg - see above for CBM US information services
advert! Some people over here claim to have achieved this already, but
none will tell me how !!!
Any changes I've missed?
Stuart Millington.
phupp@poppy.