Go Back Forums > Altair 8800 > Troubleshooting


Thread Tools Display Modes
Old 08-06-2009, 01:33 PM
phe phe is offline
Join Date: Dec 2006
Posts: 48
Default Oscilloscope tests

Hi there.

This is not really a troubleshooting question per se, but it seemed like the best place to post my question.

For the last 30+ years of dabbling in electronics, I never had a chance to use a scope. Well, I finally got one and I'm just itching to try it out. I checked the web and there are lots of tutorials, but those only explain the knobs and controls and theories, but no practical tests.

I'm in learning mode. So, here is the first stupid question: can I damage anything in the scope or, more importantly, in the 8800 by poking around with the probe?

He is the second, not so stupid (I hope) question: where are some good places to probe in order to see some interesting data on the scope?

Thanks for some advice! I look forward to learning from the masters.

Reply With Quote
Old 08-06-2009, 01:45 PM
marty marty is offline
Senior Member
Join Date: Jun 2007
Posts: 118
Talking scope

Basically there is two answers, both yes and no.... On the CPU and on the Buss , there are relatively High Voltages + _ 12 volt and on the buss + - 18 volt, and by accident or poking around , you short one of these to something else , then you you could Damage or even Blow something up (like the Cpu Ic, or some other 5 volt ic.) But, in all other cases where the voltages are the same like two ajoining data lines or two address lines or even a data and an address line, then no, it might lock things up and you would have to turn off the computer to restart it, but most of the time just hitting reset will work... You could look at almost any data line or any address line or even your clock lines and see what they look like. (on the Cpu the clock lines are 12 volt, so be carefull !!!,,, your are better to check these on the 7406).....
THANK you Marty
Reply With Quote
Old 08-14-2009, 05:57 PM
marty marty is offline
Senior Member
Join Date: Jun 2007
Posts: 118
Talking scope

Hi Paul;
I just got finished troubleshooting my Front Panel, as it would not stay in the stop mode, it would always stay in 'RUN' mode, which I traced to a Bad Ic, on the Front Panel, The stop/Run Flip-flop was not working right. The Scope made it so I could LOOK at its input and its output, and since it could not pull the signal 'low' it would stay in Run mode.... So, yes Paul , a scope is a nice thing to have....
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT. The time now is 11:49 PM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.