18 Oct
2013
18 Oct
'13
9:42 p.m.
In article <CAKtEYUyTd5kFxLcF9u7_hR2-4eQPJ4o2tFgkiDgEuzfXt10jpg at mail.gmail.com>,
Kyle Owen <kylevowen at gmail.com> writes:
On Fri, Oct 18, 2013 at 10:40 PM, Richard <legalize
at xmission.com> wrote:
It sounds like you've got it under control as far as working backwards
As usual with equipment of this age, check
capacitors and check the
power supply.
Everything else with the terminal works. Local mode works great. [...]
but pins 4 and 5 almost look like they are driven
from a capacitor, as the voltage swing starts off a little high and
gradually works its way down to nothing. from the pins to the source of the problem.
Even though everything else may seem to be working right, I'd still
check the power supply. RS-232C wants very different voltages than
what 7400 series logic chips want to see. I suppose it's possible
that one of your RS-232 transceiver chips has failed.
--
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