From: RussellMc <apptechnz@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
CC: Russell McMahon <apptechnz@gmail.com>, "ken@elecsyn.com" <ken@elecsyn.com>
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Date: Mon, 22 Mar 2021 22:42:19 -0700
Subject: Re: [EE]: 27xx64 EPROM Programmer
Thread-Topic: [EE]: 27xx64 EPROM Programmer
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On Tue, 23 Mar 2021, 17:21 Bob Blick, <bobblick@outlook.com> wrote:

> Regarding unapproved methods of erasing EPROMs, I have permanently damage=
d
> some using both sunlight and germicidal lamps.


Interesting.

While cause of failure is hard to establish without forensic analysis ( if
then) we were not of the impression that we lost any from sunshine erasure
once we started ensuring that they were well protected against
electrostatic damage. When UV exposed they seemed to be far more ESD
sensitive when UV exposed.

I do not recall any losses when using an 18 W UV tube using "long enough"
timing - possibly (but by no means certainly) due to by then ensuring great
care re ESD was taken.

Of interest is the fact that an EPROM will sometimes read unreliably if
operated under fluorescent lighting at typical levels if the "window" is
not covered. A running microcontroller program that is usually reliable can
be seen to fault with an uncovered EPROM  window.

Russell
--=20
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