$4 Serial link problem...Help !!
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$4 Serial link problem...Help !!
I built the $4 cable design for my young son from internet schematics
and have had problems...it transmits very poorly, and we have only been
able to get parts of programs downloaded to his '85. Worse, I can't
seem to interest anyone in helping with troubleshooting.
I used the ti-ti link cable and plug, and 4.7 volt diodes.
Everything looks right x3 checks, and "ohms out" ok.
Using it, at idle we get the proscribed -.7 volts on red and white
wires(tip and middle of plug), but get only 3.91 volts or so on them
when a link program is started (instead of the 4.7 volts described).
His TI 85 talks to other TI's just fine, and we get the same voltage
results with both of our available computers.
I can't figure it out...I'd sure appreciate some advice...he's pretty
disappointed. If you have any ideas, please offer them.
Best Regards,
Steve Bienvenu
bienvenu@softdisk.com or W5ZA@amsat.org
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