1) Stick a decoupling cap between the RTS and CTS lines and
earth (he thinks that was where he put them).

2) Strap the signal and frame ground lines together at the TNC
and computer end of the RS232 cable. He knows that technically
the two are supposed to be separate, but suspects that the
problem arises when the signal ground ends up at a different
potential from the frame ground. He hasn't had the TNC lock up
for 6 months or more.

Alex (G1FBY @ GB7BMX) reported that he has had his 232 for two
years. One of the first problems he encountered was lockup. All
investigations of the unit proved OK. One Sunday his XYL was
using the washing machine and dishwasher for long periods of
time and the PK232 locked up 6 times. It was run on a fully
regulated power supply. He fitted a Radio Spares spike
protection socket to the mains plug of the power supply and all
has been FB since.
Hope this is useful,
73 de Derek [G4UXD @ GB7OAR]

GW1NGL NA7KR Kevin Roberts Ham Radio

Page last updated on 09/10/2012 by Kevin Roberts NA7KR a colection of Ham Radio and Electronic Information