Re: help!? - plex thermal problem even with mod?

[Kim Flint <kflint@annihilist.com>]

Hi Dan-

you've asked about undo on the echoplex a bunch of times recently. I've
been meaning to help you out, but haven't yet had a chance to get to it. I
can get you a quick answer today:


At 8:16 PM -0700 7/7/97, dan mcmullen wrote:
>just saw the "undo == record" behavior on my new plex after having it on
>for most of today!  has anyone else seen this?
>
>the only twist to my mod was that the adc chip in my plex is socketed, so 
>i
>just bent the pin out rather than clipping it.  this should work, yes?

two possible problems:

a) you bent up the wrong pin. check the diagram on the website to make sure
you got it right.

b) it is July and you live in the Northern Hemisphere, where it is the
middle of a hot summer, and your echoplex was on all day in a poorly
ventilated room with a high ambient temperature. If that is the case, take
the advice of our friends in equatorial climates, and use a fan. Air moving
around a metal box will do a lot to remove heat. If the adc pin is cut, the
temperature has to be quite high to cause a failure, but I've seen people
do it! The heat inside a metal box enclosed in a rack can get far greater
than the air where you are sitting. Remember, all electronics devices will
fail if the heat they generate is not somehow removed. Even if there is not
some obvious problem, excessive heat will be causing many components to
slowly deteriorate, and one day you will have a problem. Take care of your
gear, keep it cool and clean, and it will last.

>my board is rev b, w/ 3.32 firmware.

that doesn't matter for this problem.


>
>tia,
>dan
>
>ps- figured out that the undo led goes on the 2nd loop after recording if
>feedback is less than 100%: you can undo the gain reduction for each loop!
>:-)  seems like this could interfere with undoing overdubs & such when
>feedback is <100% though.  is there any way to disable this behavior?

Reducing feedback is changing the loop in exactly the same way as Overdub.
Undo takes away changes made to the loop, whether they are made by overdub
or feedback or whatever. There is no way to change that or have undo
differentiate between one kind of change and another. (boy, that would be a
complicated user interface!) Take another look at the section in the manual
that explains how memory and undo are related to get a better understanding
of this. As you are probably noticing, undoing the gain changes is pretty
useful anyway!

hope this helps,

kim


>___
>dan mcmullen                               don't worry - pay attention
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______________________________________________________________________
Kim Flint                   | Looper's Delight
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