[Elecraft] KPA100 RS232 problem
Kurt Cramer
[email protected]
Tue Apr 6 18:18:00 2004
John,
Page 60 of the KPA100 manual says"U4.... converts the 5 volt logic
signals at pins 11 &12 (RX and TX data) to RS 232 levels, Typlically +/-
5 to +/- 12 VDC."
If you look with a scope and have the 0 volt line at midscale on the
screen. There will be + voltage offsets(spaces) and - voltage
offsets(marks). It's sort of a squae wave going bothways from 0 volts.
It either works or there is nothing there! I have fixed many computer
terminals here in Az that were used at 7000' on a Mt top. Generally
lighting strikes took 'em out. They also don't like working into a
short. A connector with a frayed shield causing a short to ground will
do it every time.
Good luck.
Kurt W7QHD