[Elecraft] K3(s) main oscillator calibration

[W2xj]

I have higher standards and always have.

Sent from my iPad

> On Jun 10, 2020, at 2:45 PM, Bob McGraw K4TAX <rmcgraw at blomand.net> wrote:
> 
> And perfect will never occur.  So one best think of adequate.
> 
> 73
> 
> Bob, K4TAX
> 
>> On 6/10/2020 1:42 PM, W2xj wrote:
>> adequate is not perfect. YMMV
>> 
>> Sent from my iPad
>> 
>>>> On Jun 10, 2020, at 2:07 PM, Bob McGraw K4TAX <rmcgraw at blomand.net> wrote:
>>> 
>>> In referencing TF.NIST.GOV on page 251, I find it stated;
>>> 
>>> "When high accuracy is not required, probably and fastest way of comparing the frequency of an oscillator to a broadcast standard is the familiar heterodyne or zero beat method."
>>> 
>>> And then on page 253, I find it stated;
>>> 
>>> " Usually, however, it is difficult to adjust an oscillator to exactly zero beat with an HF carrier beyond the ground wave range of the transmitter.  The problem arises from rapid fluctuations in the received signal strength and from propagation flutter in the received frequency."
>>> 
>>> References are: THE USES AND LIMITATION OF HF STANDARD BROADCAST FOR TIME AND FREQUENCY COMPARISON.  John T. Stanley, NIST.
>>> 
>>> As I indicated earlier, a frequency accuracy of +/- 1 Hz for ham radio purposes is adequate.  Likewise for time accuracy +/- 0.1 second is adequate.
>>> 
>>> 73
>>> 
>>> Bob, K4TAX
>>> 
>>> 
>>>> On 6/10/2020 11:52 AM, w4sc wrote:
>>>> How much doppler shift should be expected?
>>>> 
>>>> Sent from Mail for Windows 10
>>>> 
>>>> From: W2xj
>>>> Sent: Saturday, June 6, 2020 5:31 PM
>>>> To: w4sc
>>>> Cc: wes_n7ws at triconet.org; elecraft at mailman.qth.net
>>>> Subject: Re: [Elecraft] K3(s) main oscillator calibration
>>>> 
>>>> the problem with WWV is doppler shift.
>>>> 
>>>> Sent from my iPad
>>>> 
>>>>>> On Jun 6, 2020, at 5:27 PM, w4sc <w4sc at windstream.net> wrote:
>>>>> I like the zero beat WWV method.  Used it in the Navy to calibrate / PM the 10MHz frequency standards aboard ship. Requires the least amount of test equipment!  If you can receive WWV on 20MHz to calibrate the K3/K3S, all the better,
>>>>> 
>>>>> Using a frequency counter I would think  0.1Hz resolution and attending accuracy would be in order, plus an accurate time base in the counter, GPS locked,,, or oven-ized, on all the time reference ,,, ect.
>>>>> 
>>>>> Ben W4SC
>>>>> 
>>>>> 
>>>>> Sent from Mail for Windows 10
>>>>> 
>>>>> ______________________________________________________________
>>>>> Elecraft mailing list
>>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>>> Post: mailto:Elecraft at mailman.qth.net
>>>>> 
>>>>> This list hosted by: http://www.qsl.net
>>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>>> Message delivered to w2xj at w2xj.net
>>>>> 
>>>> ______________________________________________________________
>>>> Elecraft mailing list
>>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>>> Help: http://mailman.qth.net/mmfaq.htm
>>>> Post: mailto:Elecraft at mailman.qth.net
>>>> 
>>>> This list hosted by: http://www.qsl.net
>>>> Please help support this email list: http://www.qsl.net/donate.html
>>>> Message delivered to rmcgraw at blomand.net
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Elecraft at mailman.qth.net
>>> 
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> Message delivered to w2xj at w2xj.net
>> 
> 
>