[time-nuts] 75Z vs 50Z for GPS receivers

[Brooke Clarke]

Hi Didier:

The Tek 1502 is great for doing this, especially if you have the 
optional strip chart recorder.  It's what it was made to do.
http://www.pacificsites.com/~brooke/Tek1502.shtml

Have Fun,

Brooke Clarke

w/Java http://www.PRC68.com
w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml
http://www.precisionclock.com

 . . . .

>
>I have 3 coax runs going from my ham shack to the top of my tower to 
>feed the HF (14 to 30 MHz) and two VHF antennas (6m and 2m, or 50 MHz 
>and 144 MHz). One cable (HF) is regular RG-213, another (6m) is RG-214 
>(essentially like RG-213 with double shield), the last one (2m) is 
>Ultra-flex air dielectric (more like 9913). All 3 runs are close in 
>length, about 135 feet. I have fed them with the 1 PPS signal and looked 
>at reflections with the storage scope (that's how I know the length). It 
>is interesting to see the big reflection when the signal gets to the 
>antennas. Of course, the antennas are a poor match for the 1 PPS signal 
>(fortunately), so they are essentially a short circuit.
>
>I need to take pictures, now that it is relatively cold here (everything 
>being relative) and take the same pictures in the summer and look for 
>differences between the 3 coax lines. Out of the 135 feet, 60 feet are 
>in the air going up the tower, 50 feet are in the ground (in a 4" PVC 
>pipe), the rest is in the garage and the attic, so temperature is not 
>well controlled or constant, but it should all vary in the same direction.
>
>Didier
>
>  
>