Good afternoon all,
Finally, a TimeNuts topic that I might be able to help with! Usually I
just sit back, read, and learn from the group because y'all are way over
my head. ;)
I've been playing around with the M8T for a couple of years now, both at
work for professional applications and here at the house. At work,
we're using that second timepulse to timestamp data very accurately.
The M8T second timepulse (TP2) can indeed go from 0.25Hz to 10 MHz
output. See the last page of the product summary:
<https://www.u-blox.com/sites/default/files/products/documents/NEO-LEA-M8T_ProductSummary_%28UBX-16000801%29.pdf>
In fact, I've got an M8T right now putting out 10 MHz on TP2 with the HP
5328A telling me it's right on 10 MHz. :) One of these days, I need to
build a cable to hook up the OSC INPUT of the 5328A to the 10 MHz output
of either the Z3801A or the TruePosition. But, on the other hand, the
internal OSC isn't that bad for what I need, it's about 5 Hz high at 10
MHz when cold and that usually settles down to about 3 Hz high at 10
MHz. For hobby stuff, that's good enough! ;)
Getting TP2 set up and working with uCenter (I'm using 8.28) takes a lot
of fiddling. I don't know why! It should be so straight forward. The
best I can tell, there is something goofy going on when you try to set a
frequency and a length with uCenter...but if you click Frequency and
Duty Cycle it works. Why, I don't know. Here is a screen shot of my
TP5 settings in uCenter that are working right now:
<http://www.kd5byb.net/M8T/m8t_2.jpg>
And here is it at 5 MHz:
<http://www.kd5byb.net/M8T/m8t_3.jpg>
And the counter confirms 5 MHz output. :) If I put it on the scope,
it's a nice 50% duty square wave.
Try those settings. If you still don't get an output on TP2, my
thoughts are that you've either got a counterfeit module or something
isn't right with it.
The NEO-M8T I've got is on a PCB of my own design...and was either
bought direct from the uBlox or from Digikey / Mouser, I don't remember.
so there is a really high chance of it being genuine. ;)
Thanks much,
ben
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
