Re: Frequency Stability


Vernon Matheson
 

Thanks Hans...would I reduce the 150.000.000 maximum frequency by 28.200.000? 
 
On 11/09/17 10:54 AM, "Hans Summers" <hans.summers@...> wrote:

Hi Vernon

I suggest putting the sequence of the bands the other way around: start with the highest frequency and then step down. 

Park Mode 2 is useful in the gaps between transmissions but makes very little difference if the gap is only 8 seconds. So use Park Mode 2 for the long wait at the end of calibration and before the Mode 0] configuration starts. Have it sequence through starting at the highest frequencies then stepping lower. 

73 Hans G0UPL

On Thu, Nov 9, 2017 at 5:35 PM, Vernon Matheson <vmath@...> wrote:
 Hi all,
 
I have been trying to reduce the drift on my wspr tx when running 5-6 bands. I seem to be able to get one band with zero drift and the next band in sequence has some drift. See the data for 20m versus 30m below
 
I have attached a small heat sink on the 27mhz xtal as suggested but am wondering about park mode. U3S is also in a qrp labs case.
 
If I set to mode 2 and say 149.000.000 as suggested it doesn't change much.
 
Would I be better to use park mode #1 and then 149.000.000 for a frequency.
 
Vernon
 
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
 2017-11-09 14:24   VA1VM   14.097148   -22   -3   FN85ij   0.2   G4ZFQ   IO90ir   4509   59 
 2017-11-09 14:24   VA1VM   14.097165   -24   -2   FN85ij   0.2   F4GUK/SDR   JN18et   4828   61 
 2017-11-09 14:24   VA1VM   14.097153   -20   -3   FN85ij   0.2   K9AN   EN50wc   2102   263 
 2017-11-09 14:24   VA1VM   14.097157   -2   -3   FN85ij   0.2   W9HAM   EN64   1865   275 
 2017-11-09 14:24   VA1VM   14.097156   -22   -3   FN85ij   0.2   G0DLV   IO70ru   4286   60 
 2017-11-09 14:24   VA1VM   14.097150   -22   -3   FN85ij   0.2   G0LUJ   IO83ls   4305   55 
 2017-11-09 14:24   VA1VM   14.097157   -21   -3   FN85ij   0.2   KA4PKB   EN41kf   2287   268 
 2017-11-09 14:22   VA1VM   10.140154   -26   0   FN85ij   0.2   SWLKCL   FN03ip   1281   267 
 2017-11-09 14:22   VA1VM   10.140156   -9   0   FN85ij   0.2   SWLNXZ   FN13co   1165   265 
 2017-11-09 14:22   VA1VM   10.140153   -22   0   FN85ij   0.2   K9AN   EN50wc   2102   263 
 2017-11-09 14:22   VA1VM   10.140152   -18   0   FN85ij   0.2   VE3YX   FN16fd   1107   279 
 2017-11-09 14:22   VA1VM   10.140160   -22   0   FN85ij   0.2   VE3BSB   FN14uv   1020   272 
 2017-11-09 14:22   VA1VM   10.140153   -20   0   FN85ij   0.2   K4COD   EM73sc   2266   240 
 2017-11-09 14:22   VA1VM   10.140154   -18   0   FN85ij   0.2   K1BZ/3   FM19ne   1311   243 
 2017-11-09 14:22   VA1VM   10.140150   -21   0   FN85ij   0.2   N4CDN   FM18iu   1362   243 
 2017-11-09 14:20   VA1VM   7.040163   -27   0   FN85ij   0.2   N4TVC   FM18is   1367   242 


 

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