[Elecraft] [acom-list] Re: Elecraft K3 and ACOM 2000A

[Don Wilhelm]

David,

That is true the specification says that condition will not cause damage 
to compliant drivers and receivers, but if two drivers are placed on an 
RS-232 signal line, they will *not* work together and will result in 
corrupt data (assuming they are on the TXD or RXD signal lines).

You are correct that damage may occur to non-compliant (but compatible) 
drivers and receivers.  The PC serial cards, USB to serial adapters, and 
most ham gear do not implement compliant RS-232 interfaces.

73,
Don W3FPR

On 9/15/2014 6:14 AM, David Woolley wrote:
> It is a requirement of RS-232 that any interface pin will tolerate a 
> low impedance short circuit to anything in the range -25V to +25V, so 
> shorting two outputs together is within specification, even if the 
> resulting logic level may be indeterminate.
>
> This is only true of compliant interfaces, and not necessarily true of 
> merely compatible ones.
>