[time-nuts] Electronics Question

[lists at lazygranch.com]

Only lift the transmitter output. Note that by design, 232 ports can be floated. Receivers all have pull-down resistors. For much of the world today, if they have a 232 port, it is floating. 

A little heat and exacto knife should lift the pin just fine. I've done this before. It helps to own a stereo microscope. 

-----Original Message-----
From: Robert LaJeunesse <rlajeunesse at sbcglobal.net>
Date: Thu, 28 Jul 2011 10:51:25 
To: <lists at lazygranch.com>; Discussion of precise time and frequency measurement<time-nuts at febo.com>
Subject: Re: [time-nuts] Electronics Question

Lifting "a pin" often causes it to break off. May as well pull the part for 
later reuse. 

Agree on the inversion issue. 

One needs to be careful as 3.3V CMOS logic is usually not (or "not exactly") TTL 
compatible.

Crossing power supply boundaries means having to assure the associated pins are 
not unhappy - i.e. drawing excess current - when either supply is missing. 





________________________________
From: "lists at lazygranch.com" <lists at lazygranch.com>
To: Discussion of precise time and frequency measurement <time-nuts at febo.com>
Sent: Thu, July 28, 2011 1:39:06 PM
Subject: Re: [time-nuts] Electronics Question

Technically, he just has to lift the offending pins. My recollection is the 
transmitters invert, so that might be an issue.