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Moderately productive


[today’s run: 3.5 miles in a cold wind]

I’ve been holding down the fort here at home while my wife is on a trip with her sister. She’s running a 50 mile race down on the Florida panhandle.

I took the dog in for a bandage-and-stitches check yesterday and he seems to be healing up ok. I have been staying around the house because I don’t want him to have a lot of alone time to work on getting his bandages off. I removed his cone-collar. It didn’t seem right to have the guy spending a substantial amount of his last days in that thing. So I keep an eye on him instead. I’ve got a “bandage” made of a torn sheet which I tie over the vet’s official tape job. The dog has been able to tease things up a bit, but I just re-tie my bandage to cover it up and that keeps him happy for awhile.

He is kind of subdued, but it seems mostly from the wife being away. She’s the sparkle in this household. So he has just boring old me and that slows things down quite a bit. Otherwise, he seems to be pretty much the same as usual. He’s definitely eating well.


I’ve been working on the GPSDO problems. I really think my oscillator is having a problem. The controller card sends a control voltage to make tiny adjustments of the oscillator rate to get it to match the GPS 1 pps (pulse per second). And I think the control voltage may not be having any effect. I’m going to wait a few days and see. I really don’t have the time to dig into it any further.

I did find myself working on it some this morning. The salvage box I put it in (back in 2012) already had a “panel mount” volt meter in it which I’ve been using to monitor the control voltage. I did some work to clean up that connection and now it better shows the real control voltage being sent to the oscillator. I can see it slowly stepping up. We will find out if it ever stabilizes or if it just keeps going all the way to the maximum value.

This kind of oscillator is made for long-term stability. It has a tweak adjustment I can do with a screwdriver. So I could actually tweak it and get it into shape with the GPS for awhile. But oscillators age and it would need tweaking again (which labs have to do with their equipment – calibrate it). The GPS disciplining thing is supposed to do that automatically. Some far away government scientist tweaks the GPS time system, that then controls my oscillator and we are all in fat city. Or so we hope to be.

I have the tweak control just a little bit off so that I can see if the self adjustment works. The controller is telling me it is making small steps, and the volt meter shows the small changes in voltage. But I don’t think I’m seeing the expect curve toward a point of stability. We will let it cook and see what happens.

Jan 13, 2018
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