From: IanK at
vulcan.com
To: cctalk at
classiccmp.org
Date: Fri, 17 Dec 2010 21:55:18 -0800
Subject: RE: Need help with Project Northstar/Data I/O System-19/ADM Terminals
Many moons ago, I was responsible for the electronics in a recording studio (in the days
of analog). Given that the musicians usually smoked like stacks, I made a habit of taking
home the PCBs from the recording equipment, running the dishwasher (with no soap, as
Allison notes), drying them by hand and then airflow. Signal-to-noise ratios and
reliability of control systems increased noticeably. -- Ian
________________________________________
From: cctalk-bounces at
classiccmp.org [cctalk-bounces at
classiccmp.org] On Behalf Of
allison [ajp166 at
verizon.net]
Sent: Friday, December 17, 2010 7:02 PM
To: On-Topic Posts Only
Subject: Re: Need help with Project Northstar/Data I/O System-19/ADM Terminals
On 12/13/2010 09:56 AM, Robert J. Stevens wrote:
I am trying to restore a N* Horizon,. So far I
have got the ZPB-A2 CPU
card working. I added the Prom Option and am using a 2708 EPROM with
Monitor Code by Dave Dunfield. A Friend burnt the Prom for me but I
has a problem and doesn't get the Keyboard Input. I have tried several
times to Burn a new Prom with my D/I Sys-19 but they don't behave as
they should. I have a SOL20 System/Bus Probe Card that single steps
from the get go and I can step through the Code and see how it behaves
in relation to the .lst listing. I have been using my Canon Book 10
running "TERM" to talk to the N*. It talks OK to the Sys-19 as well as
other machines. I lost both of my Televideo 920/25's. I had three ADM
LSI's in the Shed/Barn but the Field mice made their nests in two. The
one that was untouched I brought in the Other day and It lights up the
Mini-Tracker showing that the ADM is setup as DTE. But I get no
response from the Keyboard. Tried looping back 2-3 but no display.
Don't see any Raster but the tube POPs up a spot when turned off. I am
going to try to pull the Mother board out of the Other Micey ADM.
Maybe I can swap the M/B's and see if that CRT is working. Same for
the One still in the Barn.
What would my chances be of soaking it and
getting all the CRAP off it
and having it WORK????? probably ZILCH.
Chances are very good it will work.
The process is to wash it with water and very mild soap (woolite is
good), then rinse, then rinse(not a typo)
then rinse in 91% isopropanol (drug store). Air dry then oven dry at
180F or less. In that era PCboards
after wave soldering were routinely washed in what amounted to a dish
washer.
The only item that can be twitchy for water is DIP switches as they are
hard to dry out. Isopropanol
and a can of compressed air works. One absorbs the water and the
compressed air to move it out.
I've used that approach on S100 board, terminal main boards, PC
mainboards that were dust encrusted,
whole communications radios (with some parts that cannot be wetted
removed) and after 4 decades
of doing that no damage from cleaning. My favorite method is the
dishwasher with out the usual caustic
(dishwasher soap is caustic) and nothing but water, boards usually look
as good as new.
I bought about 5 2708's and If I can find
someone who might load the
New Code for me I could send them a 2708 and E-Mail the .HEX file.
The Parts must be UV erased before programming (usually 20 mins for old
2708s), verify blank
before programming.
Allison
Hi
It is unlikely that there is a problem with the 2708s If the programmer said they
were good, I'd expect them to be fine.
The places I'd look are first the RS232 connection. The fact that the canon
book works on one machine doesn't mean it will work on another. As well
as the data lines, there are handshake wires that need to have the right
levels.
He said that he'd single stepped the code, what were the results of
that? what did it do or not do right??
Dwight