Re: TI-H: Ti-86 awesome new backlight...
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Re: TI-H: Ti-86 awesome new backlight...
>From: KrazyJolt@aol.com
>ok. I just got my calculator back, with a niftly lil' EL backlight...
the
>slowdown effect truly pissing me off. When I try and turn it on during
an ASM
>game it crashes and loses all memory! Is there a fix to stop this
obnoxious
>little side effect? Does a turbo help?
hmm, I seem to recall posting details about this before...
Turbo does not help, the problem has something to do
with the interference that the inverter causes in the
calculator power supply. If you put a scope on the
clock circuit (one side of the turbo cap), you can see
the clock pulses. When you switch the inverter on,
the pulses get screwed up.
The switching frequency of the inverter appears to
be 10KHz, output frequency is 400Hz, output voltage
is 80VAC. The waveform is hard to describe, its
kind of a rough looking sawtooth.
I tried several different kinds of filters, but
I did not measure the input inpedance of the inverter,
so the filters probably were not performing as I
wanted, I haven't gotten around to emailing the
manufacturer about them.
One concern was that the inverter may have been
overloaded, however, tests on an unloaded inverter
showed the same voltages present on the input
pins, so it doesn't look like it would matter,
althoug an unloaded inverter was not test in a
calculator.
later
DK
DK
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