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  2. #progrock GPS threshold adjustment

Re: #progrock GPS threshold adjustment #progrock #qlg1

geoff M0ORE
 

I am currently using a QLG1 GPS to drive a shack clock, ProgRock, U3S and a VFO. The 1PPS signals are put through an AND gate in the U3S and the VFO  to stop the display flashing when that unit is not in use. I haven't looked at the signal on a scope to the extent that you have but an AND gate might remove the grass that you are seeing.



On 09/01/2021 09:28, Victor 4X6GP wrote:

Here is a picture of the 1 pps pulse from my QLG1, connected to the GPS input of the Progrock:



Note the "grass" growing after the pulse. I believe that this is crosstalk from the GPS data that is also carried in the cable from the QLG1.


I wonder if this could be the cause of the poor accuracy of the Progrock's output frequency?


I would disconnect it at the GPS, but I need it for my U3S, which I also use the QLG1 with. I need to think about this.

Victor
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