[time-nuts] Mounting GPS Antenna on Steel Roof
Matthew Smith
matt at smiffytech.com
Fri Mar 7 10:04:33 UTC 2008
Quoth Hal Murray at 2008-03-07 19:59...
> The normal MAX232 type level shifters include an inverter.
>
> So even if the voltage levels work without a level shifter, the signal will
> be upside down.
I'm building my test board with a hex inverter that I'm actually using
to buffer the 1PPS signal. I've got spare gates on there so will build
the board with jumpers so that I can invert or not invert (that is the
question ;-))
As I'm working with two different types of GPS module, and may have
others, my development board will have a lot of jumpers so that I can
actually patch together something that works before I build the final
boards - something that I feel necessary as I always seem to get my
TX/RX mixed up!
Just to clarify - I don't tend to use breadboards as they tend to take
longer to debug than making a PCB. When PCBs are concerned, I tend to
use SMDs wherever possible until such time as I find a way of making
holes that a) doesn't break my drill every other hole and b) actually
lines things up properly. (A CNC XY drill rig would be really nice -
better buy a lottery ticket.)
Cheers
M
--
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
Personal: http://www.smiffysplace.com/
LinkedIn: http://www.linkedin.com/in/smiffy
More information about the Time-nuts_lists.febo.com
mailing list