Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.

Michael Shreeve
 

Hi Jerry ( and whoever else is reading) I checked my master oscillator freq , when raduino was cold, and everything else was warmed up, and found that it still says 2k high right off the bat. So, I'm working toward the possibility of calibrating my Leader Counter. I did see a blurb on from WWV where they announced that the 25.0000 signal they are transmitting is now being transmitted on a new Circularly polarized antenna. I will re-measure soon, when calibrated. I did get a lot of good info so far. Thanks for your participation. 

On Fri, Mar 9, 2018 at 10:02 AM, Michael Shreeve <shreevester@...> wrote:
Yes, 2000 is pretty much unbelievable. I'll try a couple of things,
1 measure with a scope looking at the flutter for more accuracy

2 try to check my counter using wwv ft Collins or wherever it comes from now in the same way,(possibly this should be the first step, I've put it off long enough) 

3 after I've determined a semi warm measurement where its been running continuously (I can actually measure the temp with my little orange non contact for fun, and measure the supply and 5v's just in case) , I'll turn off ONLY the uBITX and measure it in the AM . Also, I'll put a little video on for those who might want to see how I'm doing these things.

Remembering that this is a Raduino that is working quite well. This is an exercise so that I'll be VERY familiar,  for my work with an Raduino that doesn't sound so good when used..  

On Fri, Mar 9, 2018 at 9:28 AM, Michael Shreeve <shreevester@...> wrote:
Yes, I'll need to hook a scope to hear the 3 or 4 hz flutter when your spot on. Thanks Jerry. Hopefully doing more today, as its raining here finally.

On Thu, Mar 8, 2018 at 8:32 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
That's an excellent method to measure the frequency of the 25mhz oscillator.
If the receiver has sufficient low frequency audio response, you could monitor the speaker wires with a scope
and get sub hz accuracy when zero-beating.

I'll check my uBitx (tomorrow?), see how much warmup drift I can detect.
The 2.3khz drift (at 25mhz) you reported seems too large by a couple orders of magnitude. 

Jerry




On Thu, Mar 8, 2018 at 07:55 pm, Michael Shreeve wrote:
I don't know if I responded to this. I thought I explained but then maybe not. What I have always done when there is no buffered output is 1 use a receiver and an "antenna" if you will, one that is near the raduino but not touching anything. 2 turn on a somewhat stable generator and, in my case right now, measure the generator frequency directly with a counter. I can hear that generator in the same receiver.. Zero beat the generator , which is being measured, with the 25 MHz signal emanating from the raduino. Turns out it did change as I indicated, merely from heating up. No direct coupling at all for this measurement. At least to the raduino. If I had a communications monitor I wouldn't need to measure the freq of the generator. Or some other stable generator source. Also, I need to try to determine just how accurate my counter is. 
 




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Michael Shreeve N6GRG




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Michael Shreeve N6GRG




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Michael Shreeve N6GRG

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