IBM 5151 (MDA display) - common faults / gotchas?

Michael Holley swtpc6800 at
Sun Nov 9 11:20:52 CST 2014

I also lost a 5151 monitor to a program crash, it was "Gone in Sixty
Seconds" or less. I replaced it with a third party monitor that had the
advertised feature of not burning up due to lost sync.

Michael Holley
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at] On Behalf Of Chuck Guzis
Sent: Sunday, November 09, 2014 8:44 AM
To: General at; Discussion at and Off-Topic
Subject: Re: IBM 5151 (MDA display) - common faults / gotchas?

I'll add this to the 5151 issue.   Because the 5151 responds to *every* 
horizontal sync pulse, it's quite possible to toast the flyback transformer
with the wrong frequency.  I know--I've done it.

Contrast with a simple astable multivibrator which would simply lose synch .


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