[time-nuts] Mounting GPS Antenna on Steel Roof

[Matthew Smith]

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
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